Experimental parser: merge to r19637

src/a64/full-codegen-a64.cc

-// Copyright 2012 the V8 project authors. All rights reserved.
+// Copyright 2013 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
 //       with the distribution.
 //     * Neither the name of Google Inc. nor the names of its
 //       contributors may be used to endorse or promote products derived
 //       from this software without specific prior written permission.
 //
 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 #include "v8.h"
 
-#if V8_TARGET_ARCH_ARM
+#if V8_TARGET_ARCH_A64
 
 #include "code-stubs.h"
 #include "codegen.h"
 #include "compiler.h"
 #include "debug.h"
 #include "full-codegen.h"
 #include "isolate-inl.h"
 #include "parser.h"
 #include "scopes.h"
 #include "stub-cache.h"
 
-#include "arm/code-stubs-arm.h"
-#include "arm/macro-assembler-arm.h"
+#include "a64/code-stubs-a64.h"
+#include "a64/macro-assembler-a64.h"
 
 namespace v8 {
 namespace internal {
 
 #define __ ACCESS_MASM(masm_)
 
-
-// A patch site is a location in the code which it is possible to patch. This
-// class has a number of methods to emit the code which is patchable and the
-// method EmitPatchInfo to record a marker back to the patchable code. This
-// marker is a cmp rx, #yyy instruction, and x * 0x00000fff + yyy (raw 12 bit
-// immediate value is used) is the delta from the pc to the first instruction of
-// the patchable code.
 class JumpPatchSite BASE_EMBEDDED {
  public:
-  explicit JumpPatchSite(MacroAssembler* masm) : masm_(masm) {
+  explicit JumpPatchSite(MacroAssembler* masm) : masm_(masm), reg_(NoReg) {
 #ifdef DEBUG
     info_emitted_ = false;
 #endif
   }
 
   ~JumpPatchSite() {
-    ASSERT(patch_site_.is_bound() == info_emitted_);
+    if (patch_site_.is_bound()) {
+      ASSERT(info_emitted_);
+    } else {
+      ASSERT(reg_.IsNone());
+    }
   }
 
-  // When initially emitting this ensure that a jump is always generated to skip
-  // the inlined smi code.
   void EmitJumpIfNotSmi(Register reg, Label* target) {
-    ASSERT(!patch_site_.is_bound() && !info_emitted_);
-    Assembler::BlockConstPoolScope block_const_pool(masm_);
+    // This code will be patched by PatchInlinedSmiCode, in ic-a64.cc.
+    InstructionAccurateScope scope(masm_, 1);
+    ASSERT(!info_emitted_);
+    ASSERT(reg.Is64Bits());
+    ASSERT(!reg.Is(csp));
+    reg_ = reg;
     __ bind(&patch_site_);
-    __ cmp(reg, Operand(reg));
-    __ b(eq, target);  // Always taken before patched.
+    __ tbz(xzr, 0, target);   // Always taken before patched.
   }
 
-  // When initially emitting this ensure that a jump is never generated to skip
-  // the inlined smi code.
   void EmitJumpIfSmi(Register reg, Label* target) {
-    ASSERT(!patch_site_.is_bound() && !info_emitted_);
-    Assembler::BlockConstPoolScope block_const_pool(masm_);
+    // This code will be patched by PatchInlinedSmiCode, in ic-a64.cc.
+    InstructionAccurateScope scope(masm_, 1);
+    ASSERT(!info_emitted_);
+    ASSERT(reg.Is64Bits());
+    ASSERT(!reg.Is(csp));
+    reg_ = reg;
     __ bind(&patch_site_);
-    __ cmp(reg, Operand(reg));
-    __ b(ne, target);  // Never taken before patched.
+    __ tbnz(xzr, 0, target);  // Never taken before patched.
+  }
+
+  void EmitJumpIfEitherNotSmi(Register reg1, Register reg2, Label* target) {
+    // We need to use ip0, so don't allow access to the MacroAssembler.
+    InstructionAccurateScope scope(masm_);
+    __ orr(ip0, reg1, reg2);
+    EmitJumpIfNotSmi(ip0, target);
   }
 
   void EmitPatchInfo() {
-    // Block literal pool emission whilst recording patch site information.
-    Assembler::BlockConstPoolScope block_const_pool(masm_);
-    if (patch_site_.is_bound()) {
-      int delta_to_patch_site = masm_->InstructionsGeneratedSince(&patch_site_);
-      Register reg;
-      reg.set_code(delta_to_patch_site / kOff12Mask);
-      __ cmp_raw_immediate(reg, delta_to_patch_site % kOff12Mask);
+    Assembler::BlockConstPoolScope scope(masm_);
+    InlineSmiCheckInfo::Emit(masm_, reg_, &patch_site_);
 #ifdef DEBUG
-      info_emitted_ = true;
+    info_emitted_ = true;
 #endif
-    } else {
-      __ nop();  // Signals no inlined code.
-    }
   }
 
  private:
   MacroAssembler* masm_;
   Label patch_site_;
+  Register reg_;
 #ifdef DEBUG
   bool info_emitted_;
 #endif
 };
 
 
-// Generate code for a JS function.  On entry to the function the receiver
-// and arguments have been pushed on the stack left to right.  The actual
+// Generate code for a JS function. On entry to the function the receiver
+// and arguments have been pushed on the stack left to right. The actual
 // argument count matches the formal parameter count expected by the
 // function.
 //
 // The live registers are:
-//   o r1: the JS function object being called (i.e., ourselves)
-//   o cp: our context
-//   o pp: our caller's constant pool pointer (if FLAG_enable_ool_constant_pool)
-//   o fp: our caller's frame pointer
-//   o sp: stack pointer
-//   o lr: return address
+//   - x1: the JS function object being called (i.e. ourselves).
+//   - cp: our context.
+//   - fp: our caller's frame pointer.
+//   - jssp: stack pointer.
+//   - lr: return address.
 //
-// The function builds a JS frame.  Please see JavaScriptFrameConstants in
+// The function builds a JS frame. See JavaScriptFrameConstants in
 // frames-arm.h for its layout.
 void FullCodeGenerator::Generate() {
   CompilationInfo* info = info_;
   handler_table_ =
       isolate()->factory()->NewFixedArray(function()->handler_count(), TENURED);
+
+  InitializeFeedbackVector();
+
   profiling_counter_ = isolate()->factory()->NewCell(
       Handle<Smi>(Smi::FromInt(FLAG_interrupt_budget), isolate()));
   SetFunctionPosition(function());
-  Comment cmnt(masm_, "[ function compiled by full code generator");
+  Comment cmnt(masm_, "[ Function compiled by full code generator");
 
   ProfileEntryHookStub::MaybeCallEntryHook(masm_);
 
 #ifdef DEBUG
   if (strlen(FLAG_stop_at) > 0 &&
       info->function()->name()->IsUtf8EqualTo(CStrVector(FLAG_stop_at))) {
-    __ stop("stop-at");
+    __ Debug("stop-at", __LINE__, BREAK);
   }
 #endif
 
   // Classic mode functions and builtins need to replace the receiver with the
   // global proxy when called as functions (without an explicit receiver
   // object).
   if (info->is_classic_mode() && !info->is_native()) {
     Label ok;
-    int receiver_offset = info->scope()->num_parameters() * kPointerSize;
-    __ ldr(r2, MemOperand(sp, receiver_offset));
-    __ CompareRoot(r2, Heap::kUndefinedValueRootIndex);
-    __ b(ne, &ok);
+    int receiver_offset = info->scope()->num_parameters() * kXRegSizeInBytes;
+    __ Peek(x10, receiver_offset);
+    __ JumpIfNotRoot(x10, Heap::kUndefinedValueRootIndex, &ok);
 
-    __ ldr(r2, GlobalObjectOperand());
-    __ ldr(r2, FieldMemOperand(r2, GlobalObject::kGlobalReceiverOffset));
+    __ Ldr(x10, GlobalObjectMemOperand());
+    __ Ldr(x10, FieldMemOperand(x10, GlobalObject::kGlobalReceiverOffset));
+    __ Poke(x10, receiver_offset);
 
-    __ str(r2, MemOperand(sp, receiver_offset));
-
-    __ bind(&ok);
+    __ Bind(&ok);
   }
 
-  // Open a frame scope to indicate that there is a frame on the stack.  The
-  // MANUAL indicates that the scope shouldn't actually generate code to set up
-  // the frame (that is done below).
+
+  // Open a frame scope to indicate that there is a frame on the stack.
+  // The MANUAL indicates that the scope shouldn't actually generate code
+  // to set up the frame because we do it manually below.
   FrameScope frame_scope(masm_, StackFrame::MANUAL);
 
+  // This call emits the following sequence in a way that can be patched for
+  // code ageing support:
+  //  Push(lr, fp, cp, x1);
+  //  Add(fp, jssp, 2 * kPointerSize);
   info->set_prologue_offset(masm_->pc_offset());
   __ Prologue(BUILD_FUNCTION_FRAME);
   info->AddNoFrameRange(0, masm_->pc_offset());
-  __ LoadConstantPoolPointerRegister();
 
+  // Reserve space on the stack for locals.
   { Comment cmnt(masm_, "[ Allocate locals");
     int locals_count = info->scope()->num_stack_slots();
     // Generators allocate locals, if any, in context slots.
     ASSERT(!info->function()->is_generator() || locals_count == 0);
+
     if (locals_count > 0) {
-      // Emit a loop to initialize stack cells for locals when optimizing for
-      // size. Otherwise, unroll the loop for maximum performance.
-      __ LoadRoot(r9, Heap::kUndefinedValueRootIndex);
-      if (FLAG_optimize_for_size && locals_count > 4) {
-        Label loop;
-        __ mov(r2, Operand(locals_count));
-        __ bind(&loop);
-        __ sub(r2, r2, Operand(1), SetCC);
-        __ push(r9);
-        __ b(&loop, ne);
-      } else {
-        for (int i = 0; i < locals_count; i++) {
-          __ push(r9);
-        }
-      }
+      __ LoadRoot(x10, Heap::kUndefinedValueRootIndex);
+      __ PushMultipleTimes(x10, locals_count);
     }
   }
 
-  bool function_in_register = true;
+  bool function_in_register_x1 = true;
 
-  // Possibly allocate a local context.
   int heap_slots = info->scope()->num_heap_slots() - Context::MIN_CONTEXT_SLOTS;
   if (heap_slots > 0) {
-    // Argument to NewContext is the function, which is still in r1.
+    // Argument to NewContext is the function, which is still in x1.
     Comment cmnt(masm_, "[ Allocate context");
-    __ push(r1);
     if (FLAG_harmony_scoping && info->scope()->is_global_scope()) {
-      __ Push(info->scope()->GetScopeInfo());
+      __ Mov(x10, Operand(info->scope()->GetScopeInfo()));
+      __ Push(x1, x10);
       __ CallRuntime(Runtime::kNewGlobalContext, 2);
     } else if (heap_slots <= FastNewContextStub::kMaximumSlots) {
       FastNewContextStub stub(heap_slots);
       __ CallStub(&stub);
     } else {
+      __ Push(x1);
       __ CallRuntime(Runtime::kNewFunctionContext, 1);
     }
-    function_in_register = false;
-    // Context is returned in both r0 and cp.  It replaces the context
-    // passed to us.  It's saved in the stack and kept live in cp.
-    __ str(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
+    function_in_register_x1 = false;
+    // Context is returned in x0.  It replaces the context passed to us.
+    // It's saved in the stack and kept live in cp.
+    __ Mov(cp, x0);
+    __ Str(x0, MemOperand(fp, StandardFrameConstants::kContextOffset));
     // Copy any necessary parameters into the context.
     int num_parameters = info->scope()->num_parameters();
     for (int i = 0; i < num_parameters; i++) {
       Variable* var = scope()->parameter(i);
       if (var->IsContextSlot()) {
         int parameter_offset = StandardFrameConstants::kCallerSPOffset +
             (num_parameters - 1 - i) * kPointerSize;
         // Load parameter from stack.
-        __ ldr(r0, MemOperand(fp, parameter_offset));
+        __ Ldr(x10, MemOperand(fp, parameter_offset));
         // Store it in the context.
-        MemOperand target = ContextOperand(cp, var->index());
-        __ str(r0, target);
+        MemOperand target = ContextMemOperand(cp, var->index());
+        __ Str(x10, target);
 
         // Update the write barrier.
         __ RecordWriteContextSlot(
-            cp, target.offset(), r0, r3, kLRHasBeenSaved, kDontSaveFPRegs);
+            cp, target.offset(), x10, x11, kLRHasBeenSaved, kDontSaveFPRegs);
       }
     }
   }
 
   Variable* arguments = scope()->arguments();
   if (arguments != NULL) {
     // Function uses arguments object.
     Comment cmnt(masm_, "[ Allocate arguments object");
-    if (!function_in_register) {
+    if (!function_in_register_x1) {
       // Load this again, if it's used by the local context below.
-      __ ldr(r3, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset));
+      __ Ldr(x3, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset));
     } else {
-      __ mov(r3, r1);
+      __ Mov(x3, x1);
     }
     // Receiver is just before the parameters on the caller's stack.
     int num_parameters = info->scope()->num_parameters();
     int offset = num_parameters * kPointerSize;
-    __ add(r2, fp,
-           Operand(StandardFrameConstants::kCallerSPOffset + offset));
-    __ mov(r1, Operand(Smi::FromInt(num_parameters)));
-    __ Push(r3, r2, r1);
+    __ Add(x2, fp, StandardFrameConstants::kCallerSPOffset + offset);
+    __ Mov(x1, Operand(Smi::FromInt(num_parameters)));
+    __ Push(x3, x2, x1);
 
     // Arguments to ArgumentsAccessStub:
     //   function, receiver address, parameter count.
-    // The stub will rewrite receiever and parameter count if the previous
+    // The stub will rewrite receiver and parameter count if the previous
     // stack frame was an arguments adapter frame.
     ArgumentsAccessStub::Type type;
     if (!is_classic_mode()) {
       type = ArgumentsAccessStub::NEW_STRICT;
     } else if (function()->has_duplicate_parameters()) {
       type = ArgumentsAccessStub::NEW_NON_STRICT_SLOW;
     } else {
       type = ArgumentsAccessStub::NEW_NON_STRICT_FAST;
     }
     ArgumentsAccessStub stub(type);
     __ CallStub(&stub);
 
-    SetVar(arguments, r0, r1, r2);
+    SetVar(arguments, x0, x1, x2);
   }
 
   if (FLAG_trace) {
     __ CallRuntime(Runtime::kTraceEnter, 0);
   }
 
+
   // Visit the declarations and body unless there is an illegal
   // redeclaration.
   if (scope()->HasIllegalRedeclaration()) {
     Comment cmnt(masm_, "[ Declarations");
     scope()->VisitIllegalRedeclaration(this);
 
   } else {
     PrepareForBailoutForId(BailoutId::FunctionEntry(), NO_REGISTERS);
     { Comment cmnt(masm_, "[ Declarations");
-      // For named function expressions, declare the function name as a
-      // constant.
       if (scope()->is_function_scope() && scope()->function() != NULL) {
         VariableDeclaration* function = scope()->function();
         ASSERT(function->proxy()->var()->mode() == CONST ||
                function->proxy()->var()->mode() == CONST_HARMONY);
         ASSERT(function->proxy()->var()->location() != Variable::UNALLOCATED);
         VisitVariableDeclaration(function);
       }
       VisitDeclarations(scope()->declarations());
     }
+  }
 
-    { Comment cmnt(masm_, "[ Stack check");
-      PrepareForBailoutForId(BailoutId::Declarations(), NO_REGISTERS);
-      Label ok;
-      __ LoadRoot(ip, Heap::kStackLimitRootIndex);
-      __ cmp(sp, Operand(ip));
-      __ b(hs, &ok);
-      PredictableCodeSizeScope predictable(masm_, 2 * Assembler::kInstrSize);
-      __ Call(isolate()->builtins()->StackCheck(), RelocInfo::CODE_TARGET);
-      __ bind(&ok);
-    }
+  { Comment cmnt(masm_, "[ Stack check");
+    PrepareForBailoutForId(BailoutId::Declarations(), NO_REGISTERS);
+    Label ok;
+    ASSERT(jssp.Is(__ StackPointer()));
+    __ CompareRoot(jssp, Heap::kStackLimitRootIndex);
+    __ B(hs, &ok);
+    PredictableCodeSizeScope predictable(masm_,
+                                         Assembler::kCallSizeWithRelocation);
+    __ Call(isolate()->builtins()->StackCheck(), RelocInfo::CODE_TARGET);
+    __ Bind(&ok);
+  }
 
-    { Comment cmnt(masm_, "[ Body");
-      ASSERT(loop_depth() == 0);
-      VisitStatements(function()->body());
-      ASSERT(loop_depth() == 0);
-    }
+  { Comment cmnt(masm_, "[ Body");
+    ASSERT(loop_depth() == 0);
+    VisitStatements(function()->body());
+    ASSERT(loop_depth() == 0);
   }
 
   // Always emit a 'return undefined' in case control fell off the end of
   // the body.
   { Comment cmnt(masm_, "[ return <undefined>;");
-    __ LoadRoot(r0, Heap::kUndefinedValueRootIndex);
+    __ LoadRoot(x0, Heap::kUndefinedValueRootIndex);
   }
   EmitReturnSequence();
 
   // Force emit the constant pool, so it doesn't get emitted in the middle
   // of the back edge table.
   masm()->CheckConstPool(true, false);
 }
 
 
 void FullCodeGenerator::ClearAccumulator() {
-  __ mov(r0, Operand(Smi::FromInt(0)));
+  __ Mov(x0, Operand(Smi::FromInt(0)));
 }
 
 
 void FullCodeGenerator::EmitProfilingCounterDecrement(int delta) {
-  __ mov(r2, Operand(profiling_counter_));
-  __ ldr(r3, FieldMemOperand(r2, Cell::kValueOffset));
-  __ sub(r3, r3, Operand(Smi::FromInt(delta)), SetCC);
-  __ str(r3, FieldMemOperand(r2, Cell::kValueOffset));
+  __ Mov(x2, Operand(profiling_counter_));
+  __ Ldr(x3, FieldMemOperand(x2, Cell::kValueOffset));
+  __ Subs(x3, x3, Operand(Smi::FromInt(delta)));
+  __ Str(x3, FieldMemOperand(x2, Cell::kValueOffset));
 }
 
 
 void FullCodeGenerator::EmitProfilingCounterReset() {
   int reset_value = FLAG_interrupt_budget;
   if (isolate()->IsDebuggerActive()) {
     // Detect debug break requests as soon as possible.
     reset_value = FLAG_interrupt_budget >> 4;
   }
-  __ mov(r2, Operand(profiling_counter_));
-  __ mov(r3, Operand(Smi::FromInt(reset_value)));
-  __ str(r3, FieldMemOperand(r2, Cell::kValueOffset));
+  __ Mov(x2, Operand(profiling_counter_));
+  __ Mov(x3, Operand(Smi::FromInt(reset_value)));
+  __ Str(x3, FieldMemOperand(x2, Cell::kValueOffset));
 }
 
 
 void FullCodeGenerator::EmitBackEdgeBookkeeping(IterationStatement* stmt,
                                                 Label* back_edge_target) {
+  ASSERT(jssp.Is(__ StackPointer()));
   Comment cmnt(masm_, "[ Back edge bookkeeping");
   // Block literal pools whilst emitting back edge code.
   Assembler::BlockConstPoolScope block_const_pool(masm_);
   Label ok;
 
   ASSERT(back_edge_target->is_bound());
   int distance = masm_->SizeOfCodeGeneratedSince(back_edge_target);
   int weight = Min(kMaxBackEdgeWeight,
                    Max(1, distance / kCodeSizeMultiplier));
   EmitProfilingCounterDecrement(weight);
-  __ b(pl, &ok);
+  __ B(pl, &ok);
   __ Call(isolate()->builtins()->InterruptCheck(), RelocInfo::CODE_TARGET);
 
   // Record a mapping of this PC offset to the OSR id.  This is used to find
   // the AST id from the unoptimized code in order to use it as a key into
   // the deoptimization input data found in the optimized code.
   RecordBackEdge(stmt->OsrEntryId());
 
   EmitProfilingCounterReset();
 
-  __ bind(&ok);
+  __ Bind(&ok);
   PrepareForBailoutForId(stmt->EntryId(), NO_REGISTERS);
   // Record a mapping of the OSR id to this PC.  This is used if the OSR
   // entry becomes the target of a bailout.  We don't expect it to be, but
   // we want it to work if it is.
   PrepareForBailoutForId(stmt->OsrEntryId(), NO_REGISTERS);
 }
 
 
 void FullCodeGenerator::EmitReturnSequence() {
   Comment cmnt(masm_, "[ Return sequence");
+
   if (return_label_.is_bound()) {
-    __ b(&return_label_);
+    __ B(&return_label_);
+
   } else {
-    __ bind(&return_label_);
+    __ Bind(&return_label_);
     if (FLAG_trace) {
       // Push the return value on the stack as the parameter.
-      // Runtime::TraceExit returns its parameter in r0.
-      __ push(r0);
+      // Runtime::TraceExit returns its parameter in x0.
+      __ Push(result_register());
       __ CallRuntime(Runtime::kTraceExit, 1);
+      ASSERT(x0.Is(result_register()));
     }
     // Pretend that the exit is a backwards jump to the entry.
     int weight = 1;
     if (info_->ShouldSelfOptimize()) {
       weight = FLAG_interrupt_budget / FLAG_self_opt_count;
     } else {
       int distance = masm_->pc_offset();
       weight = Min(kMaxBackEdgeWeight,
                    Max(1, distance / kCodeSizeMultiplier));
     }
     EmitProfilingCounterDecrement(weight);
     Label ok;
-    __ b(pl, &ok);
-    __ push(r0);
+    __ B(pl, &ok);
+    __ Push(x0);
     __ Call(isolate()->builtins()->InterruptCheck(),
             RelocInfo::CODE_TARGET);
-    __ pop(r0);
+    __ Pop(x0);
     EmitProfilingCounterReset();
-    __ bind(&ok);
+    __ Bind(&ok);
 
-#ifdef DEBUG
-    // Add a label for checking the size of the code used for returning.
-    Label check_exit_codesize;
-    __ bind(&check_exit_codesize);
-#endif
     // Make sure that the constant pool is not emitted inside of the return
-    // sequence.
-    { Assembler::BlockConstPoolScope block_const_pool(masm_);
-      int32_t sp_delta = (info_->scope()->num_parameters() + 1) * kPointerSize;
+    // sequence. This sequence can get patched when the debugger is used. See
+    // debug-a64.cc:BreakLocationIterator::SetDebugBreakAtReturn().
+    {
+      InstructionAccurateScope scope(masm_,
+                                     Assembler::kJSRetSequenceInstructions);
       CodeGenerator::RecordPositions(masm_, function()->end_position() - 1);
-      // TODO(svenpanne) The code below is sometimes 4 words, sometimes 5!
-      PredictableCodeSizeScope predictable(masm_, -1);
       __ RecordJSReturn();
-      int no_frame_start = __ LeaveFrame(StackFrame::JAVA_SCRIPT);
-      __ add(sp, sp, Operand(sp_delta));
-      __ Jump(lr);
+      // This code is generated using Assembler methods rather than Macro
+      // Assembler methods because it will be patched later on, and so the size
+      // of the generated code must be consistent.
+      const Register& current_sp = __ StackPointer();
+      // Nothing ensures 16 bytes alignment here.
+      ASSERT(!current_sp.Is(csp));
+      __ mov(current_sp, fp);
+      int no_frame_start = masm_->pc_offset();
+      __ ldp(fp, lr, MemOperand(current_sp, 2 * kXRegSizeInBytes, PostIndex));
+      // Drop the arguments and receiver and return.
+      // TODO(all): This implementation is overkill as it supports 2**31+1
+      // arguments, consider how to improve it without creating a security
+      // hole.
+      __ LoadLiteral(ip0, 3 * kInstructionSize);
+      __ add(current_sp, current_sp, ip0);
+      __ ret();
+      __ dc64(kXRegSizeInBytes * (info_->scope()->num_parameters() + 1));
       info_->AddNoFrameRange(no_frame_start, masm_->pc_offset());
     }
-
-#ifdef DEBUG
-    // Check that the size of the code used for returning is large enough
-    // for the debugger's requirements.
-    ASSERT(Assembler::kJSReturnSequenceInstructions <=
-           masm_->InstructionsGeneratedSince(&check_exit_codesize));
-#endif
   }
 }
 
 
 void FullCodeGenerator::EffectContext::Plug(Variable* var) const {
   ASSERT(var->IsStackAllocated() || var->IsContextSlot());
 }
 
 
 void FullCodeGenerator::AccumulatorValueContext::Plug(Variable* var) const {
   ASSERT(var->IsStackAllocated() || var->IsContextSlot());
   codegen()->GetVar(result_register(), var);
 }
 
 
 void FullCodeGenerator::StackValueContext::Plug(Variable* var) const {
   ASSERT(var->IsStackAllocated() || var->IsContextSlot());
   codegen()->GetVar(result_register(), var);
-  __ push(result_register());
+  __ Push(result_register());
 }
 
 
 void FullCodeGenerator::TestContext::Plug(Variable* var) const {
   ASSERT(var->IsStackAllocated() || var->IsContextSlot());
   // For simplicity we always test the accumulator register.
   codegen()->GetVar(result_register(), var);
   codegen()->PrepareForBailoutBeforeSplit(condition(), false, NULL, NULL);
   codegen()->DoTest(this);
 }
 
 
 void FullCodeGenerator::EffectContext::Plug(Heap::RootListIndex index) const {
+  // Root values have no side effects.
 }
 
 
 void FullCodeGenerator::AccumulatorValueContext::Plug(
     Heap::RootListIndex index) const {
   __ LoadRoot(result_register(), index);
 }
 
 
 void FullCodeGenerator::StackValueContext::Plug(
     Heap::RootListIndex index) const {
   __ LoadRoot(result_register(), index);
-  __ push(result_register());
+  __ Push(result_register());
 }
 
 
 void FullCodeGenerator::TestContext::Plug(Heap::RootListIndex index) const {
-  codegen()->PrepareForBailoutBeforeSplit(condition(),
-                                          true,
-                                          true_label_,
+  codegen()->PrepareForBailoutBeforeSplit(condition(), true, true_label_,
                                           false_label_);
   if (index == Heap::kUndefinedValueRootIndex ||
       index == Heap::kNullValueRootIndex ||
       index == Heap::kFalseValueRootIndex) {
-    if (false_label_ != fall_through_) __ b(false_label_);
+    if (false_label_ != fall_through_) __ B(false_label_);
   } else if (index == Heap::kTrueValueRootIndex) {
-    if (true_label_ != fall_through_) __ b(true_label_);
+    if (true_label_ != fall_through_) __ B(true_label_);
   } else {
     __ LoadRoot(result_register(), index);
     codegen()->DoTest(this);
   }
 }
 
 
 void FullCodeGenerator::EffectContext::Plug(Handle<Object> lit) const {
 }
 
 
 void FullCodeGenerator::AccumulatorValueContext::Plug(
     Handle<Object> lit) const {
-  __ mov(result_register(), Operand(lit));
+  __ Mov(result_register(), Operand(lit));
 }
 
 
 void FullCodeGenerator::StackValueContext::Plug(Handle<Object> lit) const {
   // Immediates cannot be pushed directly.
-  __ mov(result_register(), Operand(lit));
-  __ push(result_register());
+  __ Mov(result_register(), Operand(lit));
+  __ Push(result_register());
 }
 
 
 void FullCodeGenerator::TestContext::Plug(Handle<Object> lit) const {
   codegen()->PrepareForBailoutBeforeSplit(condition(),
                                           true,
                                           true_label_,
                                           false_label_);
   ASSERT(!lit->IsUndetectableObject());  // There are no undetectable literals.
   if (lit->IsUndefined() || lit->IsNull() || lit->IsFalse()) {
-    if (false_label_ != fall_through_) __ b(false_label_);
+    if (false_label_ != fall_through_) __ B(false_label_);
   } else if (lit->IsTrue() || lit->IsJSObject()) {
-    if (true_label_ != fall_through_) __ b(true_label_);
+    if (true_label_ != fall_through_) __ B(true_label_);
   } else if (lit->IsString()) {
     if (String::cast(*lit)->length() == 0) {
-      if (false_label_ != fall_through_) __ b(false_label_);
+      if (false_label_ != fall_through_) __ B(false_label_);
     } else {
-      if (true_label_ != fall_through_) __ b(true_label_);
+      if (true_label_ != fall_through_) __ B(true_label_);
     }
   } else if (lit->IsSmi()) {
     if (Smi::cast(*lit)->value() == 0) {
-      if (false_label_ != fall_through_) __ b(false_label_);
+      if (false_label_ != fall_through_) __ B(false_label_);
     } else {
-      if (true_label_ != fall_through_) __ b(true_label_);
+      if (true_label_ != fall_through_) __ B(true_label_);
     }
   } else {
     // For simplicity we always test the accumulator register.
-    __ mov(result_register(), Operand(lit));
+    __ Mov(result_register(), Operand(lit));
     codegen()->DoTest(this);
   }
 }
 
 
 void FullCodeGenerator::EffectContext::DropAndPlug(int count,
                                                    Register reg) const {
   ASSERT(count > 0);
   __ Drop(count);
 }
 
 
 void FullCodeGenerator::AccumulatorValueContext::DropAndPlug(
     int count,
     Register reg) const {
   ASSERT(count > 0);
   __ Drop(count);
   __ Move(result_register(), reg);
 }
 
 
 void FullCodeGenerator::StackValueContext::DropAndPlug(int count,
                                                        Register reg) const {
   ASSERT(count > 0);
   if (count > 1) __ Drop(count - 1);
-  __ str(reg, MemOperand(sp, 0));
+  __ Poke(reg, 0);
 }
 
 
 void FullCodeGenerator::TestContext::DropAndPlug(int count,
                                                  Register reg) const {
   ASSERT(count > 0);
   // For simplicity we always test the accumulator register.
   __ Drop(count);
-  __ Move(result_register(), reg);
+  __ Mov(result_register(), reg);
   codegen()->PrepareForBailoutBeforeSplit(condition(), false, NULL, NULL);
   codegen()->DoTest(this);
 }
 
 
 void FullCodeGenerator::EffectContext::Plug(Label* materialize_true,
                                             Label* materialize_false) const {
   ASSERT(materialize_true == materialize_false);
-  __ bind(materialize_true);
+  __ Bind(materialize_true);
 }
 
 
 void FullCodeGenerator::AccumulatorValueContext::Plug(
     Label* materialize_true,
     Label* materialize_false) const {
   Label done;
-  __ bind(materialize_true);
+  __ Bind(materialize_true);
   __ LoadRoot(result_register(), Heap::kTrueValueRootIndex);
-  __ jmp(&done);
-  __ bind(materialize_false);
+  __ B(&done);
+  __ Bind(materialize_false);
   __ LoadRoot(result_register(), Heap::kFalseValueRootIndex);
-  __ bind(&done);
+  __ Bind(&done);
 }
 
 
 void FullCodeGenerator::StackValueContext::Plug(
     Label* materialize_true,
     Label* materialize_false) const {
   Label done;
-  __ bind(materialize_true);
-  __ LoadRoot(ip, Heap::kTrueValueRootIndex);
-  __ jmp(&done);
-  __ bind(materialize_false);
-  __ LoadRoot(ip, Heap::kFalseValueRootIndex);
-  __ bind(&done);
-  __ push(ip);
+  __ Bind(materialize_true);
+  __ LoadRoot(x10, Heap::kTrueValueRootIndex);
+  __ B(&done);
+  __ Bind(materialize_false);
+  __ LoadRoot(x10, Heap::kFalseValueRootIndex);
+  __ Bind(&done);
+  __ Push(x10);
 }
 
 
 void FullCodeGenerator::TestContext::Plug(Label* materialize_true,
                                           Label* materialize_false) const {
   ASSERT(materialize_true == true_label_);
   ASSERT(materialize_false == false_label_);
 }
 
 
 void FullCodeGenerator::EffectContext::Plug(bool flag) const {
 }
 
 
 void FullCodeGenerator::AccumulatorValueContext::Plug(bool flag) const {
   Heap::RootListIndex value_root_index =
       flag ? Heap::kTrueValueRootIndex : Heap::kFalseValueRootIndex;
   __ LoadRoot(result_register(), value_root_index);
 }
 
 
 void FullCodeGenerator::StackValueContext::Plug(bool flag) const {
   Heap::RootListIndex value_root_index =
       flag ? Heap::kTrueValueRootIndex : Heap::kFalseValueRootIndex;
-  __ LoadRoot(ip, value_root_index);
-  __ push(ip);
+  __ LoadRoot(x10, value_root_index);
+  __ Push(x10);
 }
 
 
 void FullCodeGenerator::TestContext::Plug(bool flag) const {
   codegen()->PrepareForBailoutBeforeSplit(condition(),
                                           true,
                                           true_label_,
                                           false_label_);
   if (flag) {
-    if (true_label_ != fall_through_) __ b(true_label_);
+    if (true_label_ != fall_through_) {
+      __ B(true_label_);
+    }
   } else {
-    if (false_label_ != fall_through_) __ b(false_label_);
+    if (false_label_ != fall_through_) {
+      __ B(false_label_);
+    }
   }
 }
 
 
 void FullCodeGenerator::DoTest(Expression* condition,
                                Label* if_true,
                                Label* if_false,
                                Label* fall_through) {
   Handle<Code> ic = ToBooleanStub::GetUninitialized(isolate());
-  CallIC(ic, NOT_CONTEXTUAL, condition->test_id());
-  __ tst(result_register(), result_register());
-  Split(ne, if_true, if_false, fall_through);
+  CallIC(ic, condition->test_id());
+  __ CompareAndSplit(result_register(), 0, ne, if_true, if_false, fall_through);
 }
 
 
+// If (cond), branch to if_true.
+// If (!cond), branch to if_false.
+// fall_through is used as an optimization in cases where only one branch
+// instruction is necessary.
 void FullCodeGenerator::Split(Condition cond,
                               Label* if_true,
                               Label* if_false,
                               Label* fall_through) {
   if (if_false == fall_through) {
-    __ b(cond, if_true);
+    __ B(cond, if_true);
   } else if (if_true == fall_through) {
-    __ b(NegateCondition(cond), if_false);
+    ASSERT(if_false != fall_through);
+    __ B(InvertCondition(cond), if_false);
   } else {
-    __ b(cond, if_true);
-    __ b(if_false);
+    __ B(cond, if_true);
+    __ B(if_false);
   }
 }
 
 
 MemOperand FullCodeGenerator::StackOperand(Variable* var) {
-  ASSERT(var->IsStackAllocated());
   // Offset is negative because higher indexes are at lower addresses.
-  int offset = -var->index() * kPointerSize;
+  int offset = -var->index() * kXRegSizeInBytes;
   // Adjust by a (parameter or local) base offset.
   if (var->IsParameter()) {
     offset += (info_->scope()->num_parameters() + 1) * kPointerSize;
   } else {
     offset += JavaScriptFrameConstants::kLocal0Offset;
   }
   return MemOperand(fp, offset);
 }
 
 
 MemOperand FullCodeGenerator::VarOperand(Variable* var, Register scratch) {
   ASSERT(var->IsContextSlot() || var->IsStackAllocated());
   if (var->IsContextSlot()) {
     int context_chain_length = scope()->ContextChainLength(var->scope());
     __ LoadContext(scratch, context_chain_length);
-    return ContextOperand(scratch, var->index());
+    return ContextMemOperand(scratch, var->index());
   } else {
     return StackOperand(var);
   }
 }
 
 
 void FullCodeGenerator::GetVar(Register dest, Variable* var) {
   // Use destination as scratch.
   MemOperand location = VarOperand(var, dest);
-  __ ldr(dest, location);
+  __ Ldr(dest, location);
 }
 
 
 void FullCodeGenerator::SetVar(Variable* var,
                                Register src,
                                Register scratch0,
                                Register scratch1) {
   ASSERT(var->IsContextSlot() || var->IsStackAllocated());
-  ASSERT(!scratch0.is(src));
-  ASSERT(!scratch0.is(scratch1));
-  ASSERT(!scratch1.is(src));
+  ASSERT(!AreAliased(src, scratch0, scratch1));
   MemOperand location = VarOperand(var, scratch0);
-  __ str(src, location);
+  __ Str(src, location);
 
   // Emit the write barrier code if the location is in the heap.
   if (var->IsContextSlot()) {
+    // scratch0 contains the correct context.
     __ RecordWriteContextSlot(scratch0,
                               location.offset(),
                               src,
                               scratch1,
                               kLRHasBeenSaved,
                               kDontSaveFPRegs);
   }
 }
 
 
 void FullCodeGenerator::PrepareForBailoutBeforeSplit(Expression* expr,
                                                      bool should_normalize,
                                                      Label* if_true,
                                                      Label* if_false) {
   // Only prepare for bailouts before splits if we're in a test
   // context. Otherwise, we let the Visit function deal with the
   // preparation to avoid preparing with the same AST id twice.
   if (!context()->IsTest() || !info_->IsOptimizable()) return;
 
+  // TODO(all): Investigate to see if there is something to work on here.
   Label skip;
-  if (should_normalize) __ b(&skip);
+  if (should_normalize) {
+    __ B(&skip);
+  }
   PrepareForBailout(expr, TOS_REG);
   if (should_normalize) {
-    __ LoadRoot(ip, Heap::kTrueValueRootIndex);
-    __ cmp(r0, ip);
+    __ CompareRoot(x0, Heap::kTrueValueRootIndex);
     Split(eq, if_true, if_false, NULL);
-    __ bind(&skip);
+    __ Bind(&skip);
   }
 }
 
 
 void FullCodeGenerator::EmitDebugCheckDeclarationContext(Variable* variable) {
   // The variable in the declaration always resides in the current function
   // context.
   ASSERT_EQ(0, scope()->ContextChainLength(variable->scope()));
   if (generate_debug_code_) {
     // Check that we're not inside a with or catch context.
-    __ ldr(r1, FieldMemOperand(cp, HeapObject::kMapOffset));
-    __ CompareRoot(r1, Heap::kWithContextMapRootIndex);
+    __ Ldr(x1, FieldMemOperand(cp, HeapObject::kMapOffset));
+    __ CompareRoot(x1, Heap::kWithContextMapRootIndex);
     __ Check(ne, kDeclarationInWithContext);
-    __ CompareRoot(r1, Heap::kCatchContextMapRootIndex);
+    __ CompareRoot(x1, Heap::kCatchContextMapRootIndex);
     __ Check(ne, kDeclarationInCatchContext);
   }
 }
 
 
 void FullCodeGenerator::VisitVariableDeclaration(
     VariableDeclaration* declaration) {
   // If it was not possible to allocate the variable at compile time, we
   // need to "declare" it at runtime to make sure it actually exists in the
   // local context.
   VariableProxy* proxy = declaration->proxy();
   VariableMode mode = declaration->mode();
   Variable* variable = proxy->var();
-  bool hole_init = mode == CONST || mode == CONST_HARMONY || mode == LET;
+  bool hole_init = (mode == CONST) || (mode == CONST_HARMONY) || (mode == LET);
+
   switch (variable->location()) {
     case Variable::UNALLOCATED:
       globals_->Add(variable->name(), zone());
       globals_->Add(variable->binding_needs_init()
                         ? isolate()->factory()->the_hole_value()
                         : isolate()->factory()->undefined_value(),
                     zone());
       break;
 
     case Variable::PARAMETER:
     case Variable::LOCAL:
       if (hole_init) {
         Comment cmnt(masm_, "[ VariableDeclaration");
-        __ LoadRoot(ip, Heap::kTheHoleValueRootIndex);
-        __ str(ip, StackOperand(variable));
+        __ LoadRoot(x10, Heap::kTheHoleValueRootIndex);
+        __ Str(x10, StackOperand(variable));
       }
       break;
 
     case Variable::CONTEXT:
       if (hole_init) {
         Comment cmnt(masm_, "[ VariableDeclaration");
         EmitDebugCheckDeclarationContext(variable);
-        __ LoadRoot(ip, Heap::kTheHoleValueRootIndex);
-        __ str(ip, ContextOperand(cp, variable->index()));
+        __ LoadRoot(x10, Heap::kTheHoleValueRootIndex);
+        __ Str(x10, ContextMemOperand(cp, variable->index()));
         // No write barrier since the_hole_value is in old space.
         PrepareForBailoutForId(proxy->id(), NO_REGISTERS);
       }
       break;
 
     case Variable::LOOKUP: {
       Comment cmnt(masm_, "[ VariableDeclaration");
-      __ mov(r2, Operand(variable->name()));
+      __ Mov(x2, Operand(variable->name()));
       // Declaration nodes are always introduced in one of four modes.
       ASSERT(IsDeclaredVariableMode(mode));
-      PropertyAttributes attr =
-          IsImmutableVariableMode(mode) ? READ_ONLY : NONE;
-      __ mov(r1, Operand(Smi::FromInt(attr)));
+      PropertyAttributes attr = IsImmutableVariableMode(mode) ? READ_ONLY
+                                                              : NONE;
+      __ Mov(x1, Operand(Smi::FromInt(attr)));
       // Push initial value, if any.
       // Note: For variables we must not push an initial value (such as
       // 'undefined') because we may have a (legal) redeclaration and we
       // must not destroy the current value.
       if (hole_init) {
-        __ LoadRoot(r0, Heap::kTheHoleValueRootIndex);
-        __ Push(cp, r2, r1, r0);
+        __ LoadRoot(x0, Heap::kTheHoleValueRootIndex);
+        __ Push(cp, x2, x1, x0);
       } else {
-        __ mov(r0, Operand(Smi::FromInt(0)));  // Indicates no initial value.
-        __ Push(cp, r2, r1, r0);
+        // Pushing 0 (xzr) indicates no initial value.
+        __ Push(cp, x2, x1, xzr);
       }
       __ CallRuntime(Runtime::kDeclareContextSlot, 4);
       break;
     }
   }
 }
 
 
 void FullCodeGenerator::VisitFunctionDeclaration(
     FunctionDeclaration* declaration) {
   VariableProxy* proxy = declaration->proxy();
   Variable* variable = proxy->var();
   switch (variable->location()) {
     case Variable::UNALLOCATED: {
       globals_->Add(variable->name(), zone());
       Handle<SharedFunctionInfo> function =
           Compiler::BuildFunctionInfo(declaration->fun(), script());
-      // Check for stack-overflow exception.
+      // Check for stack overflow exception.
       if (function.is_null()) return SetStackOverflow();
       globals_->Add(function, zone());
       break;
     }
 
     case Variable::PARAMETER:
     case Variable::LOCAL: {
-      Comment cmnt(masm_, "[ FunctionDeclaration");
+      Comment cmnt(masm_, "[ Function Declaration");
       VisitForAccumulatorValue(declaration->fun());
-      __ str(result_register(), StackOperand(variable));
+      __ Str(result_register(), StackOperand(variable));
       break;
     }
 
     case Variable::CONTEXT: {
-      Comment cmnt(masm_, "[ FunctionDeclaration");
+      Comment cmnt(masm_, "[ Function Declaration");
       EmitDebugCheckDeclarationContext(variable);
       VisitForAccumulatorValue(declaration->fun());
-      __ str(result_register(), ContextOperand(cp, variable->index()));
+      __ Str(result_register(), ContextMemOperand(cp, variable->index()));
       int offset = Context::SlotOffset(variable->index());
       // We know that we have written a function, which is not a smi.
       __ RecordWriteContextSlot(cp,
                                 offset,
                                 result_register(),
-                                r2,
+                                x2,
                                 kLRHasBeenSaved,
                                 kDontSaveFPRegs,
                                 EMIT_REMEMBERED_SET,
                                 OMIT_SMI_CHECK);
       PrepareForBailoutForId(proxy->id(), NO_REGISTERS);
       break;
     }
 
     case Variable::LOOKUP: {
-      Comment cmnt(masm_, "[ FunctionDeclaration");
-      __ mov(r2, Operand(variable->name()));
-      __ mov(r1, Operand(Smi::FromInt(NONE)));
-      __ Push(cp, r2, r1);
+      Comment cmnt(masm_, "[ Function Declaration");
+      __ Mov(x2, Operand(variable->name()));
+      __ Mov(x1, Operand(Smi::FromInt(NONE)));
+      __ Push(cp, x2, x1);
       // Push initial value for function declaration.
       VisitForStackValue(declaration->fun());
       __ CallRuntime(Runtime::kDeclareContextSlot, 4);
       break;
     }
   }
 }
 
 
 void FullCodeGenerator::VisitModuleDeclaration(ModuleDeclaration* declaration) {
   Variable* variable = declaration->proxy()->var();
   ASSERT(variable->location() == Variable::CONTEXT);
   ASSERT(variable->interface()->IsFrozen());
 
   Comment cmnt(masm_, "[ ModuleDeclaration");
   EmitDebugCheckDeclarationContext(variable);
 
   // Load instance object.
-  __ LoadContext(r1, scope_->ContextChainLength(scope_->GlobalScope()));
-  __ ldr(r1, ContextOperand(r1, variable->interface()->Index()));
-  __ ldr(r1, ContextOperand(r1, Context::EXTENSION_INDEX));
+  __ LoadContext(x1, scope_->ContextChainLength(scope_->GlobalScope()));
+  __ Ldr(x1, ContextMemOperand(x1, variable->interface()->Index()));
+  __ Ldr(x1, ContextMemOperand(x1, Context::EXTENSION_INDEX));
 
   // Assign it.
-  __ str(r1, ContextOperand(cp, variable->index()));
+  __ Str(x1, ContextMemOperand(cp, variable->index()));
   // We know that we have written a module, which is not a smi.
   __ RecordWriteContextSlot(cp,
                             Context::SlotOffset(variable->index()),
-                            r1,
-                            r3,
+                            x1,
+                            x3,
                             kLRHasBeenSaved,
                             kDontSaveFPRegs,
                             EMIT_REMEMBERED_SET,
                             OMIT_SMI_CHECK);
   PrepareForBailoutForId(declaration->proxy()->id(), NO_REGISTERS);
 
-  // Traverse into body.
+  // Traverse info body.
   Visit(declaration->module());
 }
 
 
 void FullCodeGenerator::VisitImportDeclaration(ImportDeclaration* declaration) {
   VariableProxy* proxy = declaration->proxy();
   Variable* variable = proxy->var();
   switch (variable->location()) {
     case Variable::UNALLOCATED:
       // TODO(rossberg)
@@ skipping 14 matching lines @@
 }
 
 
 void FullCodeGenerator::VisitExportDeclaration(ExportDeclaration* declaration) {
   // TODO(rossberg)
 }
 
 
 void FullCodeGenerator::DeclareGlobals(Handle<FixedArray> pairs) {
   // Call the runtime to declare the globals.
-  // The context is the first argument.
-  __ mov(r1, Operand(pairs));
-  __ mov(r0, Operand(Smi::FromInt(DeclareGlobalsFlags())));
-  __ Push(cp, r1, r0);
+  __ Mov(x11, Operand(pairs));
+  Register flags = xzr;
+  if (Smi::FromInt(DeclareGlobalsFlags())) {
+    flags = x10;
+  __ Mov(flags, Operand(Smi::FromInt(DeclareGlobalsFlags())));
+  }
+  __ Push(cp, x11, flags);
   __ CallRuntime(Runtime::kDeclareGlobals, 3);
   // Return value is ignored.
 }
 
 
 void FullCodeGenerator::DeclareModules(Handle<FixedArray> descriptions) {
   // Call the runtime to declare the modules.
   __ Push(descriptions);
   __ CallRuntime(Runtime::kDeclareModules, 1);
   // Return value is ignored.
 }
 
 
 void FullCodeGenerator::VisitSwitchStatement(SwitchStatement* stmt) {
+  ASM_LOCATION("FullCodeGenerator::VisitSwitchStatement");
   Comment cmnt(masm_, "[ SwitchStatement");
   Breakable nested_statement(this, stmt);
   SetStatementPosition(stmt);
 
   // Keep the switch value on the stack until a case matches.
   VisitForStackValue(stmt->tag());
   PrepareForBailoutForId(stmt->EntryId(), NO_REGISTERS);
 
   ZoneList<CaseClause*>* clauses = stmt->cases();
   CaseClause* default_clause = NULL;  // Can occur anywhere in the list.
 
   Label next_test;  // Recycled for each test.
   // Compile all the tests with branches to their bodies.
   for (int i = 0; i < clauses->length(); i++) {
     CaseClause* clause = clauses->at(i);
     clause->body_target()->Unuse();
 
     // The default is not a test, but remember it as final fall through.
     if (clause->is_default()) {
       default_clause = clause;
       continue;
     }
 
     Comment cmnt(masm_, "[ Case comparison");
-    __ bind(&next_test);
+    __ Bind(&next_test);
     next_test.Unuse();
 
     // Compile the label expression.
     VisitForAccumulatorValue(clause->label());
 
     // Perform the comparison as if via '==='.
-    __ ldr(r1, MemOperand(sp, 0));  // Switch value.
-    bool inline_smi_code = ShouldInlineSmiCase(Token::EQ_STRICT);
+    __ Peek(x1, 0);   // Switch value.
+
     JumpPatchSite patch_site(masm_);
-    if (inline_smi_code) {
+    if (ShouldInlineSmiCase(Token::EQ_STRICT)) {
       Label slow_case;
-      __ orr(r2, r1, r0);
-      patch_site.EmitJumpIfNotSmi(r2, &slow_case);
-
-      __ cmp(r1, r0);
-      __ b(ne, &next_test);
+      patch_site.EmitJumpIfEitherNotSmi(x0, x1, &slow_case);
+      __ Cmp(x1, x0);
+      __ B(ne, &next_test);
       __ Drop(1);  // Switch value is no longer needed.
-      __ b(clause->body_target());
-      __ bind(&slow_case);
+      __ B(clause->body_target());
+      __ Bind(&slow_case);
     }
 
     // Record position before stub call for type feedback.
     SetSourcePosition(clause->position());
     Handle<Code> ic = CompareIC::GetUninitialized(isolate(), Token::EQ_STRICT);
-    CallIC(ic, NOT_CONTEXTUAL, clause->CompareId());
+    CallIC(ic, clause->CompareId());
     patch_site.EmitPatchInfo();
 
     Label skip;
-    __ b(&skip);
+    __ B(&skip);
     PrepareForBailout(clause, TOS_REG);
-    __ LoadRoot(ip, Heap::kTrueValueRootIndex);
-    __ cmp(r0, ip);
-    __ b(ne, &next_test);
+    __ JumpIfNotRoot(x0, Heap::kTrueValueRootIndex, &next_test);
     __ Drop(1);
-    __ jmp(clause->body_target());
-    __ bind(&skip);
+    __ B(clause->body_target());
+    __ Bind(&skip);
 
-    __ cmp(r0, Operand::Zero());
-    __ b(ne, &next_test);
+    __ Cbnz(x0, &next_test);
     __ Drop(1);  // Switch value is no longer needed.
-    __ b(clause->body_target());
+    __ B(clause->body_target());
   }
 
   // Discard the test value and jump to the default if present, otherwise to
   // the end of the statement.
-  __ bind(&next_test);
+  __ Bind(&next_test);
   __ Drop(1);  // Switch value is no longer needed.
   if (default_clause == NULL) {
-    __ b(nested_statement.break_label());
+    __ B(nested_statement.break_label());
   } else {
-    __ b(default_clause->body_target());
+    __ B(default_clause->body_target());
   }
 
   // Compile all the case bodies.
   for (int i = 0; i < clauses->length(); i++) {
     Comment cmnt(masm_, "[ Case body");
     CaseClause* clause = clauses->at(i);
-    __ bind(clause->body_target());
+    __ Bind(clause->body_target());
     PrepareForBailoutForId(clause->EntryId(), NO_REGISTERS);
     VisitStatements(clause->statements());
   }
 
-  __ bind(nested_statement.break_label());
+  __ Bind(nested_statement.break_label());
   PrepareForBailoutForId(stmt->ExitId(), NO_REGISTERS);
 }
 
 
 void FullCodeGenerator::VisitForInStatement(ForInStatement* stmt) {
+  ASM_LOCATION("FullCodeGenerator::VisitForInStatement");
   Comment cmnt(masm_, "[ ForInStatement");
+  int slot = stmt->ForInFeedbackSlot();
+  // TODO(all): This visitor probably needs better comments and a revisit.
   SetStatementPosition(stmt);
 
   Label loop, exit;
   ForIn loop_statement(this, stmt);
   increment_loop_depth();
 
   // Get the object to enumerate over. If the object is null or undefined, skip
   // over the loop.  See ECMA-262 version 5, section 12.6.4.
   VisitForAccumulatorValue(stmt->enumerable());
-  __ LoadRoot(ip, Heap::kUndefinedValueRootIndex);
-  __ cmp(r0, ip);
-  __ b(eq, &exit);
-  Register null_value = r5;
+  __ JumpIfRoot(x0, Heap::kUndefinedValueRootIndex, &exit);
+  Register null_value = x15;
   __ LoadRoot(null_value, Heap::kNullValueRootIndex);
-  __ cmp(r0, null_value);
-  __ b(eq, &exit);
+  __ Cmp(x0, null_value);
+  __ B(eq, &exit);
 
   PrepareForBailoutForId(stmt->PrepareId(), TOS_REG);
 
   // Convert the object to a JS object.
   Label convert, done_convert;
-  __ JumpIfSmi(r0, &convert);
-  __ CompareObjectType(r0, r1, r1, FIRST_SPEC_OBJECT_TYPE);
-  __ b(ge, &done_convert);
-  __ bind(&convert);
-  __ push(r0);
+  __ JumpIfSmi(x0, &convert);
+  __ JumpIfObjectType(x0, x10, x11, FIRST_SPEC_OBJECT_TYPE, &done_convert, ge);
+  __ Bind(&convert);
+  __ Push(x0);
   __ InvokeBuiltin(Builtins::TO_OBJECT, CALL_FUNCTION);
-  __ bind(&done_convert);
-  __ push(r0);
+  __ Bind(&done_convert);
+  __ Push(x0);
 
   // Check for proxies.
   Label call_runtime;
   STATIC_ASSERT(FIRST_JS_PROXY_TYPE == FIRST_SPEC_OBJECT_TYPE);
-  __ CompareObjectType(r0, r1, r1, LAST_JS_PROXY_TYPE);
-  __ b(le, &call_runtime);
+  __ JumpIfObjectType(x0, x10, x11, LAST_JS_PROXY_TYPE, &call_runtime, le);
 
   // Check cache validity in generated code. This is a fast case for
   // the JSObject::IsSimpleEnum cache validity checks. If we cannot
   // guarantee cache validity, call the runtime system to check cache
   // validity or get the property names in a fixed array.
-  __ CheckEnumCache(null_value, &call_runtime);
+  __ CheckEnumCache(x0, null_value, x10, x11, x12, x13, &call_runtime);
 
   // The enum cache is valid.  Load the map of the object being
   // iterated over and use the cache for the iteration.
   Label use_cache;
-  __ ldr(r0, FieldMemOperand(r0, HeapObject::kMapOffset));
-  __ b(&use_cache);
+  __ Ldr(x0, FieldMemOperand(x0, HeapObject::kMapOffset));
+  __ B(&use_cache);
 
   // Get the set of properties to enumerate.
-  __ bind(&call_runtime);
-  __ push(r0);  // Duplicate the enumerable object on the stack.
+  __ Bind(&call_runtime);
+  __ Push(x0);  // Duplicate the enumerable object on the stack.
   __ CallRuntime(Runtime::kGetPropertyNamesFast, 1);
 
   // If we got a map from the runtime call, we can do a fast
   // modification check. Otherwise, we got a fixed array, and we have
   // to do a slow check.
-  Label fixed_array;
-  __ ldr(r2, FieldMemOperand(r0, HeapObject::kMapOffset));
-  __ LoadRoot(ip, Heap::kMetaMapRootIndex);
-  __ cmp(r2, ip);
-  __ b(ne, &fixed_array);
+  Label fixed_array, no_descriptors;
+  __ Ldr(x2, FieldMemOperand(x0, HeapObject::kMapOffset));
+  __ JumpIfNotRoot(x2, Heap::kMetaMapRootIndex, &fixed_array);
 
-  // We got a map in register r0. Get the enumeration cache from it.
-  Label no_descriptors;
-  __ bind(&use_cache);
+  // We got a map in register x0. Get the enumeration cache from it.
+  __ Bind(&use_cache);
 
-  __ EnumLength(r1, r0);
-  __ cmp(r1, Operand(Smi::FromInt(0)));
-  __ b(eq, &no_descriptors);
+  __ EnumLengthUntagged(x1, x0);
+  __ Cbz(x1, &no_descriptors);
 
-  __ LoadInstanceDescriptors(r0, r2);
-  __ ldr(r2, FieldMemOperand(r2, DescriptorArray::kEnumCacheOffset));
-  __ ldr(r2, FieldMemOperand(r2, DescriptorArray::kEnumCacheBridgeCacheOffset));
+  __ LoadInstanceDescriptors(x0, x2);
+  __ Ldr(x2, FieldMemOperand(x2, DescriptorArray::kEnumCacheOffset));
+  __ Ldr(x2,
+         FieldMemOperand(x2, DescriptorArray::kEnumCacheBridgeCacheOffset));
 
   // Set up the four remaining stack slots.
-  __ push(r0);  // Map.
-  __ mov(r0, Operand(Smi::FromInt(0)));
+  __ Push(x0);  // Map.
+  __ Mov(x0, Operand(Smi::FromInt(0)));
   // Push enumeration cache, enumeration cache length (as smi) and zero.
-  __ Push(r2, r1, r0);
-  __ jmp(&loop);
+  __ SmiTag(x1);
+  __ Push(x2, x1, x0);
+  __ B(&loop);
 
-  __ bind(&no_descriptors);
+  __ Bind(&no_descriptors);
   __ Drop(1);
-  __ jmp(&exit);
+  __ B(&exit);
 
-  // We got a fixed array in register r0. Iterate through that.
-  Label non_proxy;
-  __ bind(&fixed_array);
+  // We got a fixed array in register x0. Iterate through that.
+  __ Bind(&fixed_array);
 
-  Handle<Cell> cell = isolate()->factory()->NewCell(
-      Handle<Object>(Smi::FromInt(TypeFeedbackCells::kForInFastCaseMarker),
-                     isolate()));
-  RecordTypeFeedbackCell(stmt->ForInFeedbackId(), cell);
-  __ Move(r1, cell);
-  __ mov(r2, Operand(Smi::FromInt(TypeFeedbackCells::kForInSlowCaseMarker)));
-  __ str(r2, FieldMemOperand(r1, Cell::kValueOffset));
+  Handle<Object> feedback = Handle<Object>(
+      Smi::FromInt(TypeFeedbackInfo::kForInFastCaseMarker),
+      isolate());
+  StoreFeedbackVectorSlot(slot, feedback);
+  __ LoadObject(x1, FeedbackVector());
+  __ Mov(x10, Operand(Smi::FromInt(TypeFeedbackInfo::kForInSlowCaseMarker)));
+  __ Str(x10, FieldMemOperand(x1, FixedArray::OffsetOfElementAt(slot)));
 
-  __ mov(r1, Operand(Smi::FromInt(1)));  // Smi indicates slow check
-  __ ldr(r2, MemOperand(sp, 0 * kPointerSize));  // Get enumerated object
+  __ Mov(x1, Operand(Smi::FromInt(1)));  // Smi indicates slow check.
+  __ Peek(x10, 0);  // Get enumerated object.
   STATIC_ASSERT(FIRST_JS_PROXY_TYPE == FIRST_SPEC_OBJECT_TYPE);
-  __ CompareObjectType(r2, r3, r3, LAST_JS_PROXY_TYPE);
-  __ b(gt, &non_proxy);
-  __ mov(r1, Operand(Smi::FromInt(0)));  // Zero indicates proxy
-  __ bind(&non_proxy);
-  __ Push(r1, r0);  // Smi and array
-  __ ldr(r1, FieldMemOperand(r0, FixedArray::kLengthOffset));
-  __ mov(r0, Operand(Smi::FromInt(0)));
-  __ Push(r1, r0);  // Fixed array length (as smi) and initial index.
+  // TODO(all): similar check was done already. Can we avoid it here?
+  __ CompareObjectType(x10, x11, x12, LAST_JS_PROXY_TYPE);
+  ASSERT(Smi::FromInt(0) == 0);
+  __ CzeroX(x1, le);  // Zero indicates proxy.
+  __ Push(x1, x0);  // Smi and array
+  __ Ldr(x1, FieldMemOperand(x0, FixedArray::kLengthOffset));
+  __ Push(x1, xzr);  // Fixed array length (as smi) and initial index.
 
   // Generate code for doing the condition check.
   PrepareForBailoutForId(stmt->BodyId(), NO_REGISTERS);
-  __ bind(&loop);
-  // Load the current count to r0, load the length to r1.
-  __ Ldrd(r0, r1, MemOperand(sp, 0 * kPointerSize));
-  __ cmp(r0, r1);  // Compare to the array length.
-  __ b(hs, loop_statement.break_label());
+  __ Bind(&loop);
+  // Load the current count to x0, load the length to x1.
+  __ PeekPair(x0, x1, 0);
+  __ Cmp(x0, x1);  // Compare to the array length.
+  __ B(hs, loop_statement.break_label());
 
   // Get the current entry of the array into register r3.
-  __ ldr(r2, MemOperand(sp, 2 * kPointerSize));
-  __ add(r2, r2, Operand(FixedArray::kHeaderSize - kHeapObjectTag));
-  __ ldr(r3, MemOperand::PointerAddressFromSmiKey(r2, r0));
+  __ Peek(x10, 2 * kXRegSizeInBytes);
+  __ Add(x10, x10, Operand::UntagSmiAndScale(x0, kPointerSizeLog2));
+  __ Ldr(x3, MemOperand(x10, FixedArray::kHeaderSize - kHeapObjectTag));
 
   // Get the expected map from the stack or a smi in the
-  // permanent slow case into register r2.
-  __ ldr(r2, MemOperand(sp, 3 * kPointerSize));
+  // permanent slow case into register x10.
+  __ Peek(x2, 3 * kXRegSizeInBytes);
 
   // Check if the expected map still matches that of the enumerable.
   // If not, we may have to filter the key.
   Label update_each;
-  __ ldr(r1, MemOperand(sp, 4 * kPointerSize));
-  __ ldr(r4, FieldMemOperand(r1, HeapObject::kMapOffset));
-  __ cmp(r4, Operand(r2));
-  __ b(eq, &update_each);
+  __ Peek(x1, 4 * kXRegSizeInBytes);
+  __ Ldr(x11, FieldMemOperand(x1, HeapObject::kMapOffset));
+  __ Cmp(x11, x2);
+  __ B(eq, &update_each);
 
   // For proxies, no filtering is done.
   // TODO(rossberg): What if only a prototype is a proxy? Not specified yet.
-  __ cmp(r2, Operand(Smi::FromInt(0)));
-  __ b(eq, &update_each);
+  STATIC_ASSERT(kSmiTag == 0);
+  __ Cbz(x2, &update_each);
 
   // Convert the entry to a string or (smi) 0 if it isn't a property
   // any more. If the property has been removed while iterating, we
   // just skip it.
-  __ push(r1);  // Enumerable.
-  __ push(r3);  // Current entry.
+  __ Push(x1, x3);
   __ InvokeBuiltin(Builtins::FILTER_KEY, CALL_FUNCTION);
-  __ mov(r3, Operand(r0), SetCC);
-  __ b(eq, loop_statement.continue_label());
+  __ Mov(x3, x0);
+  __ Cbz(x0, loop_statement.continue_label());
 
   // Update the 'each' property or variable from the possibly filtered
-  // entry in register r3.
-  __ bind(&update_each);
-  __ mov(result_register(), r3);
+  // entry in register x3.
+  __ Bind(&update_each);
+  __ Mov(result_register(), x3);
   // Perform the assignment as if via '='.
   { EffectContext context(this);
     EmitAssignment(stmt->each());
   }
 
   // Generate code for the body of the loop.
   Visit(stmt->body());
 
-  // Generate code for the going to the next element by incrementing
+  // Generate code for going to the next element by incrementing
   // the index (smi) stored on top of the stack.
-  __ bind(loop_statement.continue_label());
-  __ pop(r0);
-  __ add(r0, r0, Operand(Smi::FromInt(1)));
-  __ push(r0);
+  __ Bind(loop_statement.continue_label());
+  // TODO(all): We could use a callee saved register to avoid popping.
+  __ Pop(x0);
+  __ Add(x0, x0, Operand(Smi::FromInt(1)));
+  __ Push(x0);
 
   EmitBackEdgeBookkeeping(stmt, &loop);
-  __ b(&loop);
+  __ B(&loop);
 
   // Remove the pointers stored on the stack.
-  __ bind(loop_statement.break_label());
+  __ Bind(loop_statement.break_label());
   __ Drop(5);
 
   // Exit and decrement the loop depth.
   PrepareForBailoutForId(stmt->ExitId(), NO_REGISTERS);
-  __ bind(&exit);
+  __ Bind(&exit);
   decrement_loop_depth();
 }
 
 
 void FullCodeGenerator::VisitForOfStatement(ForOfStatement* stmt) {
   Comment cmnt(masm_, "[ ForOfStatement");
   SetStatementPosition(stmt);
 
   Iteration loop_statement(this, stmt);
   increment_loop_depth();
 
   // var iterator = iterable[@@iterator]()
   VisitForAccumulatorValue(stmt->assign_iterator());
 
   // As with for-in, skip the loop if the iterator is null or undefined.
-  __ CompareRoot(r0, Heap::kUndefinedValueRootIndex);
-  __ b(eq, loop_statement.break_label());
-  __ CompareRoot(r0, Heap::kNullValueRootIndex);
-  __ b(eq, loop_statement.break_label());
+  Register iterator = x0;
+  __ JumpIfRoot(iterator, Heap::kUndefinedValueRootIndex,
+                loop_statement.break_label());
+  __ JumpIfRoot(iterator, Heap::kNullValueRootIndex,
+                loop_statement.break_label());
 
   // Convert the iterator to a JS object.
   Label convert, done_convert;
-  __ JumpIfSmi(r0, &convert);
-  __ CompareObjectType(r0, r1, r1, FIRST_SPEC_OBJECT_TYPE);
-  __ b(ge, &done_convert);
-  __ bind(&convert);
-  __ push(r0);
+  __ JumpIfSmi(iterator, &convert);
+  __ CompareObjectType(iterator, x1, x1, FIRST_SPEC_OBJECT_TYPE);
+  __ B(ge, &done_convert);
+  __ Bind(&convert);
+  __ Push(iterator);
   __ InvokeBuiltin(Builtins::TO_OBJECT, CALL_FUNCTION);
-  __ bind(&done_convert);
-  __ push(r0);
+  __ Bind(&done_convert);
+  __ Push(iterator);
 
   // Loop entry.
-  __ bind(loop_statement.continue_label());
+  __ Bind(loop_statement.continue_label());
 
   // result = iterator.next()
   VisitForEffect(stmt->next_result());
 
   // if (result.done) break;
   Label result_not_done;
   VisitForControl(stmt->result_done(),
                   loop_statement.break_label(),
                   &result_not_done,
                   &result_not_done);
-  __ bind(&result_not_done);
+  __ Bind(&result_not_done);
 
   // each = result.value
   VisitForEffect(stmt->assign_each());
 
   // Generate code for the body of the loop.
   Visit(stmt->body());
 
   // Check stack before looping.
   PrepareForBailoutForId(stmt->BackEdgeId(), NO_REGISTERS);
   EmitBackEdgeBookkeeping(stmt, loop_statement.continue_label());
-  __ jmp(loop_statement.continue_label());
+  __ B(loop_statement.continue_label());
 
   // Exit and decrement the loop depth.
   PrepareForBailoutForId(stmt->ExitId(), NO_REGISTERS);
-  __ bind(loop_statement.break_label());
+  __ Bind(loop_statement.break_label());
   decrement_loop_depth();
 }
 
 
 void FullCodeGenerator::EmitNewClosure(Handle<SharedFunctionInfo> info,
                                        bool pretenure) {
-  // Use the fast case closure allocation code that allocates in new
-  // space for nested functions that don't need literals cloning. If
-  // we're running with the --always-opt or the --prepare-always-opt
-  // flag, we need to use the runtime function so that the new function
-  // we are creating here gets a chance to have its code optimized and
-  // doesn't just get a copy of the existing unoptimized code.
+  // Use the fast case closure allocation code that allocates in new space for
+  // nested functions that don't need literals cloning. If we're running with
+  // the --always-opt or the --prepare-always-opt flag, we need to use the
+  // runtime function so that the new function we are creating here gets a
+  // chance to have its code optimized and doesn't just get a copy of the
+  // existing unoptimized code.
   if (!FLAG_always_opt &&
       !FLAG_prepare_always_opt &&
       !pretenure &&
       scope()->is_function_scope() &&
       info->num_literals() == 0) {
     FastNewClosureStub stub(info->language_mode(), info->is_generator());
-    __ mov(r2, Operand(info));
+    __ Mov(x2, Operand(info));
     __ CallStub(&stub);
   } else {
-    __ mov(r0, Operand(info));
-    __ LoadRoot(r1, pretenure ? Heap::kTrueValueRootIndex
-                              : Heap::kFalseValueRootIndex);
-    __ Push(cp, r0, r1);
+    __ Mov(x11, Operand(info));
+    __ LoadRoot(x10, pretenure ? Heap::kTrueValueRootIndex
+                               : Heap::kFalseValueRootIndex);
+    __ Push(cp, x11, x10);
     __ CallRuntime(Runtime::kNewClosure, 3);
   }
-  context()->Plug(r0);
+  context()->Plug(x0);
 }
 
 
 void FullCodeGenerator::VisitVariableProxy(VariableProxy* expr) {
   Comment cmnt(masm_, "[ VariableProxy");
   EmitVariableLoad(expr);
 }
 
 
 void FullCodeGenerator::EmitLoadGlobalCheckExtensions(Variable* var,
                                                       TypeofState typeof_state,
                                                       Label* slow) {
   Register current = cp;
-  Register next = r1;
-  Register temp = r2;
+  Register next = x10;
+  Register temp = x11;
 
   Scope* s = scope();
   while (s != NULL) {
     if (s->num_heap_slots() > 0) {
       if (s->calls_non_strict_eval()) {
         // Check that extension is NULL.
-        __ ldr(temp, ContextOperand(current, Context::EXTENSION_INDEX));
-        __ tst(temp, temp);
-        __ b(ne, slow);
+        __ Ldr(temp, ContextMemOperand(current, Context::EXTENSION_INDEX));
+        __ Cbnz(temp, slow);
       }
       // Load next context in chain.
-      __ ldr(next, ContextOperand(current, Context::PREVIOUS_INDEX));
+      __ Ldr(next, ContextMemOperand(current, Context::PREVIOUS_INDEX));
       // Walk the rest of the chain without clobbering cp.
       current = next;
     }
     // If no outer scope calls eval, we do not need to check more
     // context extensions.
     if (!s->outer_scope_calls_non_strict_eval() || s->is_eval_scope()) break;
     s = s->outer_scope();
   }
 
   if (s->is_eval_scope()) {
     Label loop, fast;
-    if (!current.is(next)) {
-      __ Move(next, current);
-    }
-    __ bind(&loop);
+    __ Mov(next, current);
+
+    __ Bind(&loop);
     // Terminate at native context.
-    __ ldr(temp, FieldMemOperand(next, HeapObject::kMapOffset));
-    __ LoadRoot(ip, Heap::kNativeContextMapRootIndex);
-    __ cmp(temp, ip);
-    __ b(eq, &fast);
+    __ Ldr(temp, FieldMemOperand(next, HeapObject::kMapOffset));
+    __ JumpIfRoot(temp, Heap::kNativeContextMapRootIndex, &fast);
     // Check that extension is NULL.
-    __ ldr(temp, ContextOperand(next, Context::EXTENSION_INDEX));
-    __ tst(temp, temp);
-    __ b(ne, slow);
+    __ Ldr(temp, ContextMemOperand(next, Context::EXTENSION_INDEX));
+    __ Cbnz(temp, slow);
     // Load next context in chain.
-    __ ldr(next, ContextOperand(next, Context::PREVIOUS_INDEX));
-    __ b(&loop);
-    __ bind(&fast);
+    __ Ldr(next, ContextMemOperand(next, Context::PREVIOUS_INDEX));
+    __ B(&loop);
+    __ Bind(&fast);
   }
 
-  __ ldr(r0, GlobalObjectOperand());
-  __ mov(r2, Operand(var->name()));
-  ContextualMode mode = (typeof_state == INSIDE_TYPEOF)
-      ? NOT_CONTEXTUAL
-      : CONTEXTUAL;
+  __ Ldr(x0, GlobalObjectMemOperand());
+  __ Mov(x2, Operand(var->name()));
+  ContextualMode mode = (typeof_state == INSIDE_TYPEOF) ? NOT_CONTEXTUAL
+                                                        : CONTEXTUAL;
   CallLoadIC(mode);
 }
 
 
 MemOperand FullCodeGenerator::ContextSlotOperandCheckExtensions(Variable* var,
                                                                 Label* slow) {
   ASSERT(var->IsContextSlot());
   Register context = cp;
-  Register next = r3;
-  Register temp = r4;
+  Register next = x10;
+  Register temp = x11;
 
   for (Scope* s = scope(); s != var->scope(); s = s->outer_scope()) {
     if (s->num_heap_slots() > 0) {
       if (s->calls_non_strict_eval()) {
         // Check that extension is NULL.
-        __ ldr(temp, ContextOperand(context, Context::EXTENSION_INDEX));
-        __ tst(temp, temp);
-        __ b(ne, slow);
+        __ Ldr(temp, ContextMemOperand(context, Context::EXTENSION_INDEX));
+        __ Cbnz(temp, slow);
       }
-      __ ldr(next, ContextOperand(context, Context::PREVIOUS_INDEX));
+      __ Ldr(next, ContextMemOperand(context, Context::PREVIOUS_INDEX));
       // Walk the rest of the chain without clobbering cp.
       context = next;
     }
   }
   // Check that last extension is NULL.
-  __ ldr(temp, ContextOperand(context, Context::EXTENSION_INDEX));
-  __ tst(temp, temp);
-  __ b(ne, slow);
+  __ Ldr(temp, ContextMemOperand(context, Context::EXTENSION_INDEX));
+  __ Cbnz(temp, slow);
 
   // This function is used only for loads, not stores, so it's safe to
   // return an cp-based operand (the write barrier cannot be allowed to
   // destroy the cp register).
-  return ContextOperand(context, var->index());
+  return ContextMemOperand(context, var->index());
 }
 
 
 void FullCodeGenerator::EmitDynamicLookupFastCase(Variable* var,
                                                   TypeofState typeof_state,
                                                   Label* slow,
                                                   Label* done) {
   // Generate fast-case code for variables that might be shadowed by
   // eval-introduced variables.  Eval is used a lot without
   // introducing variables.  In those cases, we do not want to
   // perform a runtime call for all variables in the scope
   // containing the eval.
   if (var->mode() == DYNAMIC_GLOBAL) {
     EmitLoadGlobalCheckExtensions(var, typeof_state, slow);
-    __ jmp(done);
+    __ B(done);
   } else if (var->mode() == DYNAMIC_LOCAL) {
     Variable* local = var->local_if_not_shadowed();
-    __ ldr(r0, ContextSlotOperandCheckExtensions(local, slow));
+    __ Ldr(x0, ContextSlotOperandCheckExtensions(local, slow));
     if (local->mode() == LET ||
         local->mode() == CONST ||
         local->mode() == CONST_HARMONY) {
-      __ CompareRoot(r0, Heap::kTheHoleValueRootIndex);
+      __ JumpIfNotRoot(x0, Heap::kTheHoleValueRootIndex, done);
       if (local->mode() == CONST) {
-        __ LoadRoot(r0, Heap::kUndefinedValueRootIndex, eq);
+        __ LoadRoot(x0, Heap::kUndefinedValueRootIndex);
       } else {  // LET || CONST_HARMONY
-        __ b(ne, done);
-        __ mov(r0, Operand(var->name()));
-        __ push(r0);
+        __ Mov(x0, Operand(var->name()));
+        __ Push(x0);
         __ CallRuntime(Runtime::kThrowReferenceError, 1);
       }
     }
-    __ jmp(done);
+    __ B(done);
   }
 }
 
 
 void FullCodeGenerator::EmitVariableLoad(VariableProxy* proxy) {
   // Record position before possible IC call.
   SetSourcePosition(proxy->position());
   Variable* var = proxy->var();
 
   // Three cases: global variables, lookup variables, and all other types of
   // variables.
   switch (var->location()) {
     case Variable::UNALLOCATED: {
       Comment cmnt(masm_, "Global variable");
-      // Use inline caching. Variable name is passed in r2 and the global
-      // object (receiver) in r0.
-      __ ldr(r0, GlobalObjectOperand());
-      __ mov(r2, Operand(var->name()));
+      // Use inline caching. Variable name is passed in x2 and the global
+      // object (receiver) in x0.
+      __ Ldr(x0, GlobalObjectMemOperand());
+      __ Mov(x2, Operand(var->name()));
       CallLoadIC(CONTEXTUAL);
-      context()->Plug(r0);
+      context()->Plug(x0);
       break;
     }
 
     case Variable::PARAMETER:
     case Variable::LOCAL:
     case Variable::CONTEXT: {
       Comment cmnt(masm_, var->IsContextSlot()
                               ? "Context variable"
                               : "Stack variable");
       if (var->binding_needs_init()) {
@@ skipping 26 matching lines @@
         } else {
           // Check that we always have valid source position.
           ASSERT(var->initializer_position() != RelocInfo::kNoPosition);
           ASSERT(proxy->position() != RelocInfo::kNoPosition);
           skip_init_check = var->mode() != CONST &&
               var->initializer_position() < proxy->position();
         }
 
         if (!skip_init_check) {
           // Let and const need a read barrier.
-          GetVar(r0, var);
-          __ CompareRoot(r0, Heap::kTheHoleValueRootIndex);
+          GetVar(x0, var);
+          Label done;
+          __ JumpIfNotRoot(x0, Heap::kTheHoleValueRootIndex, &done);
           if (var->mode() == LET || var->mode() == CONST_HARMONY) {
             // Throw a reference error when using an uninitialized let/const
             // binding in harmony mode.
-            Label done;
-            __ b(ne, &done);
-            __ mov(r0, Operand(var->name()));
-            __ push(r0);
+            __ Mov(x0, Operand(var->name()));
+            __ Push(x0);
             __ CallRuntime(Runtime::kThrowReferenceError, 1);
-            __ bind(&done);
+            __ Bind(&done);
           } else {
             // Uninitalized const bindings outside of harmony mode are unholed.
             ASSERT(var->mode() == CONST);
-            __ LoadRoot(r0, Heap::kUndefinedValueRootIndex, eq);
+            __ LoadRoot(x0, Heap::kUndefinedValueRootIndex);
+            __ Bind(&done);
           }
-          context()->Plug(r0);
+          context()->Plug(x0);
           break;
         }
       }
       context()->Plug(var);
       break;
     }
 
     case Variable::LOOKUP: {
       Label done, slow;
-      // Generate code for loading from variables potentially shadowed
-      // by eval-introduced variables.
+      // Generate code for loading from variables potentially shadowed by
+      // eval-introduced variables.
       EmitDynamicLookupFastCase(var, NOT_INSIDE_TYPEOF, &slow, &done);
-      __ bind(&slow);
+      __ Bind(&slow);
       Comment cmnt(masm_, "Lookup variable");
-      __ mov(r1, Operand(var->name()));
-      __ Push(cp, r1);  // Context and name.
+      __ Mov(x1, Operand(var->name()));
+      __ Push(cp, x1);  // Context and name.
       __ CallRuntime(Runtime::kLoadContextSlot, 2);
-      __ bind(&done);
-      context()->Plug(r0);
+      __ Bind(&done);
+      context()->Plug(x0);
+      break;
     }
   }
 }
 
 
 void FullCodeGenerator::VisitRegExpLiteral(RegExpLiteral* expr) {
   Comment cmnt(masm_, "[ RegExpLiteral");
   Label materialized;
   // Registers will be used as follows:
-  // r5 = materialized value (RegExp literal)
-  // r4 = JS function, literals array
-  // r3 = literal index
-  // r2 = RegExp pattern
-  // r1 = RegExp flags
-  // r0 = RegExp literal clone
-  __ ldr(r0, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset));
-  __ ldr(r4, FieldMemOperand(r0, JSFunction::kLiteralsOffset));
+  // x5 = materialized value (RegExp literal)
+  // x4 = JS function, literals array
+  // x3 = literal index
+  // x2 = RegExp pattern
+  // x1 = RegExp flags
+  // x0 = RegExp literal clone
+  __ Ldr(x10, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset));
+  __ Ldr(x4, FieldMemOperand(x10, JSFunction::kLiteralsOffset));
   int literal_offset =
       FixedArray::kHeaderSize + expr->literal_index() * kPointerSize;
-  __ ldr(r5, FieldMemOperand(r4, literal_offset));
-  __ LoadRoot(ip, Heap::kUndefinedValueRootIndex);
-  __ cmp(r5, ip);
-  __ b(ne, &materialized);
+  __ Ldr(x5, FieldMemOperand(x4, literal_offset));
+  __ JumpIfNotRoot(x5, Heap::kUndefinedValueRootIndex, &materialized);
 
   // Create regexp literal using runtime function.
-  // Result will be in r0.
-  __ mov(r3, Operand(Smi::FromInt(expr->literal_index())));
-  __ mov(r2, Operand(expr->pattern()));
-  __ mov(r1, Operand(expr->flags()));
-  __ Push(r4, r3, r2, r1);
+  // Result will be in x0.
+  __ Mov(x3, Operand(Smi::FromInt(expr->literal_index())));
+  __ Mov(x2, Operand(expr->pattern()));
+  __ Mov(x1, Operand(expr->flags()));
+  __ Push(x4, x3, x2, x1);
   __ CallRuntime(Runtime::kMaterializeRegExpLiteral, 4);
-  __ mov(r5, r0);
+  __ Mov(x5, x0);
 
-  __ bind(&materialized);
+  __ Bind(&materialized);
   int size = JSRegExp::kSize + JSRegExp::kInObjectFieldCount * kPointerSize;
   Label allocated, runtime_allocate;
-  __ Allocate(size, r0, r2, r3, &runtime_allocate, TAG_OBJECT);
-  __ jmp(&allocated);
+  __ Allocate(size, x0, x2, x3, &runtime_allocate, TAG_OBJECT);
+  __ B(&allocated);
 
-  __ bind(&runtime_allocate);
-  __ mov(r0, Operand(Smi::FromInt(size)));
-  __ Push(r5, r0);
+  __ Bind(&runtime_allocate);
+  __ Mov(x10, Operand(Smi::FromInt(size)));
+  __ Push(x5, x10);
   __ CallRuntime(Runtime::kAllocateInNewSpace, 1);
-  __ pop(r5);
+  __ Pop(x5);
 
-  __ bind(&allocated);
+  __ Bind(&allocated);
   // After this, registers are used as follows:
-  // r0: Newly allocated regexp.
-  // r5: Materialized regexp.
-  // r2: temp.
-  __ CopyFields(r0, r5, d0, size / kPointerSize);
-  context()->Plug(r0);
+  // x0: Newly allocated regexp.
+  // x5: Materialized regexp.
+  // x10, x11, x12: temps.
+  __ CopyFields(x0, x5, CPURegList(x10, x11, x12), size / kPointerSize);
+  context()->Plug(x0);
 }
 
 
 void FullCodeGenerator::EmitAccessor(Expression* expression) {
   if (expression == NULL) {
-    __ LoadRoot(r1, Heap::kNullValueRootIndex);
-    __ push(r1);
+    __ LoadRoot(x10, Heap::kNullValueRootIndex);
+    __ Push(x10);
   } else {
     VisitForStackValue(expression);
   }
 }
 
 
 void FullCodeGenerator::VisitObjectLiteral(ObjectLiteral* expr) {
   Comment cmnt(masm_, "[ ObjectLiteral");
 
   expr->BuildConstantProperties(isolate());
   Handle<FixedArray> constant_properties = expr->constant_properties();
-  __ ldr(r3, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset));
-  __ ldr(r3, FieldMemOperand(r3, JSFunction::kLiteralsOffset));
-  __ mov(r2, Operand(Smi::FromInt(expr->literal_index())));
-  __ mov(r1, Operand(constant_properties));
+  __ Ldr(x3, MemOperand(fp,  JavaScriptFrameConstants::kFunctionOffset));
+  __ Ldr(x3, FieldMemOperand(x3, JSFunction::kLiteralsOffset));
+  __ Mov(x2, Operand(Smi::FromInt(expr->literal_index())));
+  __ Mov(x1, Operand(constant_properties));
   int flags = expr->fast_elements()
       ? ObjectLiteral::kFastElements
       : ObjectLiteral::kNoFlags;
   flags |= expr->has_function()
       ? ObjectLiteral::kHasFunction
       : ObjectLiteral::kNoFlags;
-  __ mov(r0, Operand(Smi::FromInt(flags)));
+  __ Mov(x0, Operand(Smi::FromInt(flags)));
   int properties_count = constant_properties->length() / 2;
+  const int max_cloned_properties =
+      FastCloneShallowObjectStub::kMaximumClonedProperties;
   if ((FLAG_track_double_fields && expr->may_store_doubles()) ||
-      expr->depth() > 1 || Serializer::enabled() ||
-      flags != ObjectLiteral::kFastElements ||
-      properties_count > FastCloneShallowObjectStub::kMaximumClonedProperties) {
-    __ Push(r3, r2, r1, r0);
+      (expr->depth() > 1) || Serializer::enabled() ||
+      (flags != ObjectLiteral::kFastElements) ||
+      (properties_count > max_cloned_properties)) {
+    __ Push(x3, x2, x1, x0);
     __ CallRuntime(Runtime::kCreateObjectLiteral, 4);
   } else {
     FastCloneShallowObjectStub stub(properties_count);
     __ CallStub(&stub);
   }
 
   // If result_saved is true the result is on top of the stack.  If
-  // result_saved is false the result is in r0.
+  // result_saved is false the result is in x0.
   bool result_saved = false;
 
   // Mark all computed expressions that are bound to a key that
   // is shadowed by a later occurrence of the same key. For the
   // marked expressions, no store code is emitted.
   expr->CalculateEmitStore(zone());
 
   AccessorTable accessor_table(zone());
   for (int i = 0; i < expr->properties()->length(); i++) {
     ObjectLiteral::Property* property = expr->properties()->at(i);
     if (property->IsCompileTimeValue()) continue;
 
     Literal* key = property->key();
     Expression* value = property->value();
     if (!result_saved) {
-      __ push(r0);  // Save result on stack
+      __ Push(x0);  // Save result on stack
       result_saved = true;
     }
     switch (property->kind()) {
       case ObjectLiteral::Property::CONSTANT:
         UNREACHABLE();
       case ObjectLiteral::Property::MATERIALIZED_LITERAL:
         ASSERT(!CompileTimeValue::IsCompileTimeValue(property->value()));
         // Fall through.
       case ObjectLiteral::Property::COMPUTED:
         if (key->value()->IsInternalizedString()) {
           if (property->emit_store()) {
             VisitForAccumulatorValue(value);
-            __ mov(r2, Operand(key->value()));
-            __ ldr(r1, MemOperand(sp));
-            CallStoreIC(NOT_CONTEXTUAL, key->LiteralFeedbackId());
+            __ Mov(x2, Operand(key->value()));
+            __ Peek(x1, 0);
+            CallStoreIC(key->LiteralFeedbackId());
             PrepareForBailoutForId(key->id(), NO_REGISTERS);
           } else {
             VisitForEffect(value);
           }
           break;
         }
         // Duplicate receiver on stack.
-        __ ldr(r0, MemOperand(sp));
-        __ push(r0);
+        __ Peek(x0, 0);
+        __ Push(x0);
         VisitForStackValue(key);
         VisitForStackValue(value);
         if (property->emit_store()) {
-          __ mov(r0, Operand(Smi::FromInt(NONE)));  // PropertyAttributes
-          __ push(r0);
+          __ Mov(x0, Operand(Smi::FromInt(NONE)));  // PropertyAttributes
+          __ Push(x0);
           __ CallRuntime(Runtime::kSetProperty, 4);
         } else {
           __ Drop(3);
         }
         break;
       case ObjectLiteral::Property::PROTOTYPE:
         // Duplicate receiver on stack.
-        __ ldr(r0, MemOperand(sp));
-        __ push(r0);
+        __ Peek(x0, 0);
+        // TODO(jbramley): This push shouldn't be necessary if we don't call the
+        // runtime below. In that case, skip it.
+        __ Push(x0);
         VisitForStackValue(value);
         if (property->emit_store()) {
           __ CallRuntime(Runtime::kSetPrototype, 2);
         } else {
           __ Drop(2);
         }
         break;
-
       case ObjectLiteral::Property::GETTER:
         accessor_table.lookup(key)->second->getter = value;
         break;
       case ObjectLiteral::Property::SETTER:
         accessor_table.lookup(key)->second->setter = value;
         break;
     }
   }
 
   // Emit code to define accessors, using only a single call to the runtime for
   // each pair of corresponding getters and setters.
   for (AccessorTable::Iterator it = accessor_table.begin();
        it != accessor_table.end();
        ++it) {
-    __ ldr(r0, MemOperand(sp));  // Duplicate receiver.
-    __ push(r0);
-    VisitForStackValue(it->first);
-    EmitAccessor(it->second->getter);
-    EmitAccessor(it->second->setter);
-    __ mov(r0, Operand(Smi::FromInt(NONE)));
-    __ push(r0);
-    __ CallRuntime(Runtime::kDefineOrRedefineAccessorProperty, 5);
+      __ Peek(x10, 0);  // Duplicate receiver.
+      __ Push(x10);
+      VisitForStackValue(it->first);
+      EmitAccessor(it->second->getter);
+      EmitAccessor(it->second->setter);
+      __ Mov(x10, Operand(Smi::FromInt(NONE)));
+      __ Push(x10);
+      __ CallRuntime(Runtime::kDefineOrRedefineAccessorProperty, 5);
   }
 
   if (expr->has_function()) {
     ASSERT(result_saved);
-    __ ldr(r0, MemOperand(sp));
-    __ push(r0);
+    __ Peek(x0, 0);
+    __ Push(x0);
     __ CallRuntime(Runtime::kToFastProperties, 1);
   }
 
   if (result_saved) {
     context()->PlugTOS();
   } else {
-    context()->Plug(r0);
+    context()->Plug(x0);
   }
 }
 
 
 void FullCodeGenerator::VisitArrayLiteral(ArrayLiteral* expr) {
   Comment cmnt(masm_, "[ ArrayLiteral");
 
   expr->BuildConstantElements(isolate());
-  int flags = expr->depth() == 1
-      ? ArrayLiteral::kShallowElements
-      : ArrayLiteral::kNoFlags;
+  int flags = (expr->depth() == 1) ? ArrayLiteral::kShallowElements
+                                   : ArrayLiteral::kNoFlags;
 
   ZoneList<Expression*>* subexprs = expr->values();
   int length = subexprs->length();
   Handle<FixedArray> constant_elements = expr->constant_elements();
   ASSERT_EQ(2, constant_elements->length());
   ElementsKind constant_elements_kind =
       static_cast<ElementsKind>(Smi::cast(constant_elements->get(0))->value());
   bool has_fast_elements = IsFastObjectElementsKind(constant_elements_kind);
   Handle<FixedArrayBase> constant_elements_values(
       FixedArrayBase::cast(constant_elements->get(1)));
 
   AllocationSiteMode allocation_site_mode = TRACK_ALLOCATION_SITE;
   if (has_fast_elements && !FLAG_allocation_site_pretenuring) {
     // If the only customer of allocation sites is transitioning, then
     // we can turn it off if we don't have anywhere else to transition to.
     allocation_site_mode = DONT_TRACK_ALLOCATION_SITE;
   }
 
-  __ ldr(r3, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset));
-  __ ldr(r3, FieldMemOperand(r3, JSFunction::kLiteralsOffset));
-  __ mov(r2, Operand(Smi::FromInt(expr->literal_index())));
-  __ mov(r1, Operand(constant_elements));
+  __ Ldr(x3, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset));
+  __ Ldr(x3, FieldMemOperand(x3, JSFunction::kLiteralsOffset));
+  // TODO(jbramley): Can these Operand constructors be implicit?
+  __ Mov(x2, Operand(Smi::FromInt(expr->literal_index())));
+  __ Mov(x1, Operand(constant_elements));
   if (has_fast_elements && constant_elements_values->map() ==
       isolate()->heap()->fixed_cow_array_map()) {
     FastCloneShallowArrayStub stub(
         FastCloneShallowArrayStub::COPY_ON_WRITE_ELEMENTS,
         allocation_site_mode,
         length);
     __ CallStub(&stub);
     __ IncrementCounter(
-        isolate()->counters()->cow_arrays_created_stub(), 1, r1, r2);
-  } else if (expr->depth() > 1 || Serializer::enabled() ||
+        isolate()->counters()->cow_arrays_created_stub(), 1, x10, x11);
+  } else if ((expr->depth() > 1) || Serializer::enabled() ||
              length > FastCloneShallowArrayStub::kMaximumClonedLength) {
-    __ mov(r0, Operand(Smi::FromInt(flags)));
-    __ Push(r3, r2, r1, r0);
+    __ Mov(x0, Operand(Smi::FromInt(flags)));
+    __ Push(x3, x2, x1, x0);
     __ CallRuntime(Runtime::kCreateArrayLiteral, 4);
   } else {
     ASSERT(IsFastSmiOrObjectElementsKind(constant_elements_kind) ||
            FLAG_smi_only_arrays);
     FastCloneShallowArrayStub::Mode mode =
         FastCloneShallowArrayStub::CLONE_ANY_ELEMENTS;
 
     if (has_fast_elements) {
       mode = FastCloneShallowArrayStub::CLONE_ELEMENTS;
     }
 
     FastCloneShallowArrayStub stub(mode, allocation_site_mode, length);
     __ CallStub(&stub);
   }
 
   bool result_saved = false;  // Is the result saved to the stack?
 
   // Emit code to evaluate all the non-constant subexpressions and to store
   // them into the newly cloned array.
   for (int i = 0; i < length; i++) {
     Expression* subexpr = subexprs->at(i);
     // If the subexpression is a literal or a simple materialized literal it
     // is already set in the cloned array.
     if (CompileTimeValue::IsCompileTimeValue(subexpr)) continue;
 
     if (!result_saved) {
-      __ push(r0);
+      __ Push(x0);
       __ Push(Smi::FromInt(expr->literal_index()));
       result_saved = true;
     }
     VisitForAccumulatorValue(subexpr);
 
     if (IsFastObjectElementsKind(constant_elements_kind)) {
       int offset = FixedArray::kHeaderSize + (i * kPointerSize);
-      __ ldr(r6, MemOperand(sp, kPointerSize));  // Copy of array literal.
-      __ ldr(r1, FieldMemOperand(r6, JSObject::kElementsOffset));
-      __ str(result_register(), FieldMemOperand(r1, offset));
+      __ Peek(x6, kPointerSize);  // Copy of array literal.
+      __ Ldr(x1, FieldMemOperand(x6, JSObject::kElementsOffset));
+      __ Str(result_register(), FieldMemOperand(x1, offset));
       // Update the write barrier for the array store.
-      __ RecordWriteField(r1, offset, result_register(), r2,
+      __ RecordWriteField(x1, offset, result_register(), x10,
                           kLRHasBeenSaved, kDontSaveFPRegs,
                           EMIT_REMEMBERED_SET, INLINE_SMI_CHECK);
     } else {
-      __ mov(r3, Operand(Smi::FromInt(i)));
+      __ Mov(x3, Operand(Smi::FromInt(i)));
       StoreArrayLiteralElementStub stub;
       __ CallStub(&stub);
     }
 
     PrepareForBailoutForId(expr->GetIdForElement(i), NO_REGISTERS);
   }
 
   if (result_saved) {
-    __ pop();  // literal index
+    __ Drop(1);   // literal index
     context()->PlugTOS();
   } else {
-    context()->Plug(r0);
+    context()->Plug(x0);
   }
 }
 
 
 void FullCodeGenerator::VisitAssignment(Assignment* expr) {
   Comment cmnt(masm_, "[ Assignment");
   // Invalid left-hand sides are rewritten to have a 'throw ReferenceError'
   // on the left-hand side.
   if (!expr->target()->IsValidLeftHandSide()) {
     VisitForEffect(expr->target());
@@ skipping 13 matching lines @@
 
   // Evaluate LHS expression.
   switch (assign_type) {
     case VARIABLE:
       // Nothing to do here.
       break;
     case NAMED_PROPERTY:
       if (expr->is_compound()) {
         // We need the receiver both on the stack and in the accumulator.
         VisitForAccumulatorValue(property->obj());
-        __ push(result_register());
+        __ Push(result_register());
       } else {
         VisitForStackValue(property->obj());
       }
       break;
     case KEYED_PROPERTY:
       if (expr->is_compound()) {
         VisitForStackValue(property->obj());
         VisitForAccumulatorValue(property->key());
-        __ ldr(r1, MemOperand(sp, 0));
-        __ push(r0);
+        __ Peek(x1, 0);
+        __ Push(x0);
       } else {
         VisitForStackValue(property->obj());
         VisitForStackValue(property->key());
       }
       break;
   }
 
   // For compound assignments we need another deoptimization point after the
   // variable/property load.
   if (expr->is_compound()) {
     { AccumulatorValueContext context(this);
       switch (assign_type) {
         case VARIABLE:
           EmitVariableLoad(expr->target()->AsVariableProxy());
           PrepareForBailout(expr->target(), TOS_REG);
           break;
         case NAMED_PROPERTY:
           EmitNamedPropertyLoad(property);
           PrepareForBailoutForId(property->LoadId(), TOS_REG);
           break;
         case KEYED_PROPERTY:
           EmitKeyedPropertyLoad(property);
           PrepareForBailoutForId(property->LoadId(), TOS_REG);
           break;
       }
     }
 
     Token::Value op = expr->binary_op();
-    __ push(r0);  // Left operand goes on the stack.
+    __ Push(x0);  // Left operand goes on the stack.
     VisitForAccumulatorValue(expr->value());
 
     OverwriteMode mode = expr->value()->ResultOverwriteAllowed()
         ? OVERWRITE_RIGHT
         : NO_OVERWRITE;
     SetSourcePosition(expr->position() + 1);
     AccumulatorValueContext context(this);
     if (ShouldInlineSmiCase(op)) {
       EmitInlineSmiBinaryOp(expr->binary_operation(),
                             op,
@@ skipping 12 matching lines @@
 
   // Record source position before possible IC call.
   SetSourcePosition(expr->position());
 
   // Store the value.
   switch (assign_type) {
     case VARIABLE:
       EmitVariableAssignment(expr->target()->AsVariableProxy()->var(),
                              expr->op());
       PrepareForBailoutForId(expr->AssignmentId(), TOS_REG);
-      context()->Plug(r0);
+      context()->Plug(x0);
       break;
     case NAMED_PROPERTY:
       EmitNamedPropertyAssignment(expr);
       break;
     case KEYED_PROPERTY:
       EmitKeyedPropertyAssignment(expr);
       break;
   }
 }
 
 
-void FullCodeGenerator::VisitYield(Yield* expr) {
-  Comment cmnt(masm_, "[ Yield");
-  // Evaluate yielded value first; the initial iterator definition depends on
-  // this.  It stays on the stack while we update the iterator.
-  VisitForStackValue(expr->expression());
-
-  switch (expr->yield_kind()) {
-    case Yield::SUSPEND:
-      // Pop value from top-of-stack slot; box result into result register.
-      EmitCreateIteratorResult(false);
-      __ push(result_register());
-      // Fall through.
-    case Yield::INITIAL: {
-      Label suspend, continuation, post_runtime, resume;
-
-      __ jmp(&suspend);
-
-      __ bind(&continuation);
-      __ jmp(&resume);
-
-      __ bind(&suspend);
-      VisitForAccumulatorValue(expr->generator_object());
-      ASSERT(continuation.pos() > 0 && Smi::IsValid(continuation.pos()));
-      __ mov(r1, Operand(Smi::FromInt(continuation.pos())));
-      __ str(r1, FieldMemOperand(r0, JSGeneratorObject::kContinuationOffset));
-      __ str(cp, FieldMemOperand(r0, JSGeneratorObject::kContextOffset));
-      __ mov(r1, cp);
-      __ RecordWriteField(r0, JSGeneratorObject::kContextOffset, r1, r2,
-                          kLRHasBeenSaved, kDontSaveFPRegs);
-      __ add(r1, fp, Operand(StandardFrameConstants::kExpressionsOffset));
-      __ cmp(sp, r1);
-      __ b(eq, &post_runtime);
-      __ push(r0);  // generator object
-      __ CallRuntime(Runtime::kSuspendJSGeneratorObject, 1);
-      __ ldr(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
-      __ bind(&post_runtime);
-      __ pop(result_register());
-      EmitReturnSequence();
-
-      __ bind(&resume);
-      context()->Plug(result_register());
-      break;
-    }
-
-    case Yield::FINAL: {
-      VisitForAccumulatorValue(expr->generator_object());
-      __ mov(r1, Operand(Smi::FromInt(JSGeneratorObject::kGeneratorClosed)));
-      __ str(r1, FieldMemOperand(result_register(),
-                                 JSGeneratorObject::kContinuationOffset));
-      // Pop value from top-of-stack slot, box result into result register.
-      EmitCreateIteratorResult(true);
-      EmitUnwindBeforeReturn();
-      EmitReturnSequence();
-      break;
-    }
-
-    case Yield::DELEGATING: {
-      VisitForStackValue(expr->generator_object());
-
-      // Initial stack layout is as follows:
-      // [sp + 1 * kPointerSize] iter
-      // [sp + 0 * kPointerSize] g
-
-      Label l_catch, l_try, l_suspend, l_continuation, l_resume;
-      Label l_next, l_call, l_loop;
-      // Initial send value is undefined.
-      __ LoadRoot(r0, Heap::kUndefinedValueRootIndex);
-      __ b(&l_next);
-
-      // catch (e) { receiver = iter; f = 'throw'; arg = e; goto l_call; }
-      __ bind(&l_catch);
-      handler_table()->set(expr->index(), Smi::FromInt(l_catch.pos()));
-      __ LoadRoot(r2, Heap::kthrow_stringRootIndex);     // "throw"
-      __ ldr(r3, MemOperand(sp, 1 * kPointerSize));      // iter
-      __ Push(r3, r0);                                   // iter, exception
-      __ jmp(&l_call);
-
-      // try { received = %yield result }
-      // Shuffle the received result above a try handler and yield it without
-      // re-boxing.
-      __ bind(&l_try);
-      __ pop(r0);                                        // result
-      __ PushTryHandler(StackHandler::CATCH, expr->index());
-      const int handler_size = StackHandlerConstants::kSize;
-      __ push(r0);                                       // result
-      __ jmp(&l_suspend);
-      __ bind(&l_continuation);
-      __ jmp(&l_resume);
-      __ bind(&l_suspend);
-      const int generator_object_depth = kPointerSize + handler_size;
-      __ ldr(r0, MemOperand(sp, generator_object_depth));
-      __ push(r0);                                       // g
-      ASSERT(l_continuation.pos() > 0 && Smi::IsValid(l_continuation.pos()));
-      __ mov(r1, Operand(Smi::FromInt(l_continuation.pos())));
-      __ str(r1, FieldMemOperand(r0, JSGeneratorObject::kContinuationOffset));
-      __ str(cp, FieldMemOperand(r0, JSGeneratorObject::kContextOffset));
-      __ mov(r1, cp);
-      __ RecordWriteField(r0, JSGeneratorObject::kContextOffset, r1, r2,
-                          kLRHasBeenSaved, kDontSaveFPRegs);
-      __ CallRuntime(Runtime::kSuspendJSGeneratorObject, 1);
-      __ ldr(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
-      __ pop(r0);                                        // result
-      EmitReturnSequence();
-      __ bind(&l_resume);                                // received in r0
-      __ PopTryHandler();
-
-      // receiver = iter; f = 'next'; arg = received;
-      __ bind(&l_next);
-      __ LoadRoot(r2, Heap::knext_stringRootIndex);      // "next"
-      __ ldr(r3, MemOperand(sp, 1 * kPointerSize));      // iter
-      __ Push(r3, r0);                                   // iter, received
-
-      // result = receiver[f](arg);
-      __ bind(&l_call);
-      Handle<Code> ic = isolate()->stub_cache()->ComputeKeyedCallInitialize(1);
-      CallIC(ic);
-      __ ldr(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
-
-      // if (!result.done) goto l_try;
-      __ bind(&l_loop);
-      __ push(r0);                                       // save result
-      __ LoadRoot(r2, Heap::kdone_stringRootIndex);      // "done"
-      CallLoadIC(NOT_CONTEXTUAL);                        // result.done in r0
-      Handle<Code> bool_ic = ToBooleanStub::GetUninitialized(isolate());
-      CallIC(bool_ic);
-      __ cmp(r0, Operand(0));
-      __ b(eq, &l_try);
-
-      // result.value
-      __ pop(r0);                                        // result
-      __ LoadRoot(r2, Heap::kvalue_stringRootIndex);     // "value"
-      CallLoadIC(NOT_CONTEXTUAL);                        // result.value in r0
-      context()->DropAndPlug(2, r0);                     // drop iter and g
-      break;
-    }
-  }
-}
-
-
-void FullCodeGenerator::EmitGeneratorResume(Expression *generator,
-    Expression *value,
-    JSGeneratorObject::ResumeMode resume_mode) {
-  // The value stays in r0, and is ultimately read by the resumed generator, as
-  // if the CallRuntime(Runtime::kSuspendJSGeneratorObject) returned it. Or it
-  // is read to throw the value when the resumed generator is already closed.
-  // r1 will hold the generator object until the activation has been resumed.
-  VisitForStackValue(generator);
-  VisitForAccumulatorValue(value);
-  __ pop(r1);
-
-  // Check generator state.
-  Label wrong_state, closed_state, done;
-  __ ldr(r3, FieldMemOperand(r1, JSGeneratorObject::kContinuationOffset));
-  STATIC_ASSERT(JSGeneratorObject::kGeneratorExecuting < 0);
-  STATIC_ASSERT(JSGeneratorObject::kGeneratorClosed == 0);
-  __ cmp(r3, Operand(Smi::FromInt(0)));
-  __ b(eq, &closed_state);
-  __ b(lt, &wrong_state);
-
-  // Load suspended function and context.
-  __ ldr(cp, FieldMemOperand(r1, JSGeneratorObject::kContextOffset));
-  __ ldr(r4, FieldMemOperand(r1, JSGeneratorObject::kFunctionOffset));
-
-  // Load receiver and store as the first argument.
-  __ ldr(r2, FieldMemOperand(r1, JSGeneratorObject::kReceiverOffset));
-  __ push(r2);
-
-  // Push holes for the rest of the arguments to the generator function.
-  __ ldr(r3, FieldMemOperand(r4, JSFunction::kSharedFunctionInfoOffset));
-  __ ldr(r3,
-         FieldMemOperand(r3, SharedFunctionInfo::kFormalParameterCountOffset));
-  __ LoadRoot(r2, Heap::kTheHoleValueRootIndex);
-  Label push_argument_holes, push_frame;
-  __ bind(&push_argument_holes);
-  __ sub(r3, r3, Operand(Smi::FromInt(1)), SetCC);
-  __ b(mi, &push_frame);
-  __ push(r2);
-  __ jmp(&push_argument_holes);
-
-  // Enter a new JavaScript frame, and initialize its slots as they were when
-  // the generator was suspended.
-  Label resume_frame;
-  __ bind(&push_frame);
-  __ bl(&resume_frame);
-  __ jmp(&done);
-  __ bind(&resume_frame);
-  // lr = return address.
-  // fp = caller's frame pointer.
-  // pp = caller's constant pool (if FLAG_enable_ool_constant_pool),
-  // cp = callee's context,
-  // r4 = callee's JS function.
-  __ PushFixedFrame(r4);
-  // Adjust FP to point to saved FP.
-  __ add(fp, sp, Operand(StandardFrameConstants::kFixedFrameSizeFromFp));
-
-  // Load the operand stack size.
-  __ ldr(r3, FieldMemOperand(r1, JSGeneratorObject::kOperandStackOffset));
-  __ ldr(r3, FieldMemOperand(r3, FixedArray::kLengthOffset));
-  __ SmiUntag(r3);
-
-  // If we are sending a value and there is no operand stack, we can jump back
-  // in directly.
-  if (resume_mode == JSGeneratorObject::NEXT) {
-    Label slow_resume;
-    __ cmp(r3, Operand(0));
-    __ b(ne, &slow_resume);
-    __ ldr(r3, FieldMemOperand(r4, JSFunction::kCodeEntryOffset));
-    __ ldr(r2, FieldMemOperand(r1, JSGeneratorObject::kContinuationOffset));
-    __ SmiUntag(r2);
-    __ add(r3, r3, r2);
-    __ mov(r2, Operand(Smi::FromInt(JSGeneratorObject::kGeneratorExecuting)));
-    __ str(r2, FieldMemOperand(r1, JSGeneratorObject::kContinuationOffset));
-    __ Jump(r3);
-    __ bind(&slow_resume);
-  }
-
-  // Otherwise, we push holes for the operand stack and call the runtime to fix
-  // up the stack and the handlers.
-  Label push_operand_holes, call_resume;
-  __ bind(&push_operand_holes);
-  __ sub(r3, r3, Operand(1), SetCC);
-  __ b(mi, &call_resume);
-  __ push(r2);
-  __ b(&push_operand_holes);
-  __ bind(&call_resume);
-  ASSERT(!result_register().is(r1));
-  __ Push(r1, result_register());
-  __ Push(Smi::FromInt(resume_mode));
-  __ CallRuntime(Runtime::kResumeJSGeneratorObject, 3);
-  // Not reached: the runtime call returns elsewhere.
-  __ stop("not-reached");
-
-  // Reach here when generator is closed.
-  __ bind(&closed_state);
-  if (resume_mode == JSGeneratorObject::NEXT) {
-    // Return completed iterator result when generator is closed.
-    __ LoadRoot(r2, Heap::kUndefinedValueRootIndex);
-    __ push(r2);
-    // Pop value from top-of-stack slot; box result into result register.
-    EmitCreateIteratorResult(true);
-  } else {
-    // Throw the provided value.
-    __ push(r0);
-    __ CallRuntime(Runtime::kThrow, 1);
-  }
-  __ jmp(&done);
-
-  // Throw error if we attempt to operate on a running generator.
-  __ bind(&wrong_state);
-  __ push(r1);
-  __ CallRuntime(Runtime::kThrowGeneratorStateError, 1);
-
-  __ bind(&done);
-  context()->Plug(result_register());
-}
-
-
-void FullCodeGenerator::EmitCreateIteratorResult(bool done) {
-  Label gc_required;
-  Label allocated;
-
-  Handle<Map> map(isolate()->native_context()->generator_result_map());
-
-  __ Allocate(map->instance_size(), r0, r2, r3, &gc_required, TAG_OBJECT);
-  __ jmp(&allocated);
-
-  __ bind(&gc_required);
-  __ Push(Smi::FromInt(map->instance_size()));
-  __ CallRuntime(Runtime::kAllocateInNewSpace, 1);
-  __ ldr(context_register(),
-         MemOperand(fp, StandardFrameConstants::kContextOffset));
-
-  __ bind(&allocated);
-  __ mov(r1, Operand(map));
-  __ pop(r2);
-  __ mov(r3, Operand(isolate()->factory()->ToBoolean(done)));
-  __ mov(r4, Operand(isolate()->factory()->empty_fixed_array()));
-  ASSERT_EQ(map->instance_size(), 5 * kPointerSize);
-  __ str(r1, FieldMemOperand(r0, HeapObject::kMapOffset));
-  __ str(r4, FieldMemOperand(r0, JSObject::kPropertiesOffset));
-  __ str(r4, FieldMemOperand(r0, JSObject::kElementsOffset));
-  __ str(r2,
-         FieldMemOperand(r0, JSGeneratorObject::kResultValuePropertyOffset));
-  __ str(r3,
-         FieldMemOperand(r0, JSGeneratorObject::kResultDonePropertyOffset));
-
-  // Only the value field needs a write barrier, as the other values are in the
-  // root set.
-  __ RecordWriteField(r0, JSGeneratorObject::kResultValuePropertyOffset,
-                      r2, r3, kLRHasBeenSaved, kDontSaveFPRegs);
-}
-
-
 void FullCodeGenerator::EmitNamedPropertyLoad(Property* prop) {
   SetSourcePosition(prop->position());
   Literal* key = prop->key()->AsLiteral();
-  __ mov(r2, Operand(key->value()));
-  // Call load IC. It has arguments receiver and property name r0 and r2.
+  __ Mov(x2, Operand(key->value()));
+  // Call load IC. It has arguments receiver and property name x0 and x2.
   CallLoadIC(NOT_CONTEXTUAL, prop->PropertyFeedbackId());
 }
 
 
 void FullCodeGenerator::EmitKeyedPropertyLoad(Property* prop) {
   SetSourcePosition(prop->position());
   // Call keyed load IC. It has arguments key and receiver in r0 and r1.
   Handle<Code> ic = isolate()->builtins()->KeyedLoadIC_Initialize();
-  CallIC(ic, NOT_CONTEXTUAL, prop->PropertyFeedbackId());
+  CallIC(ic, prop->PropertyFeedbackId());
 }
 
 
 void FullCodeGenerator::EmitInlineSmiBinaryOp(BinaryOperation* expr,
                                               Token::Value op,
                                               OverwriteMode mode,
                                               Expression* left_expr,
                                               Expression* right_expr) {
-  Label done, smi_case, stub_call;
-
-  Register scratch1 = r2;
-  Register scratch2 = r3;
+  Label done, both_smis, stub_call;
 
   // Get the arguments.
-  Register left = r1;
-  Register right = r0;
-  __ pop(left);
+  Register left = x1;
+  Register right = x0;
+  Register result = x0;
+  __ Pop(left);
 
   // Perform combined smi check on both operands.
-  __ orr(scratch1, left, Operand(right));
-  STATIC_ASSERT(kSmiTag == 0);
+  __ Orr(x10, left, right);
   JumpPatchSite patch_site(masm_);
-  patch_site.EmitJumpIfSmi(scratch1, &smi_case);
+  patch_site.EmitJumpIfSmi(x10, &both_smis);
 
-  __ bind(&stub_call);
+  __ Bind(&stub_call);
   BinaryOpICStub stub(op, mode);
-  CallIC(stub.GetCode(isolate()), NOT_CONTEXTUAL,
-         expr->BinaryOperationFeedbackId());
-  patch_site.EmitPatchInfo();
-  __ jmp(&done);
+  {
+    Assembler::BlockConstPoolScope scope(masm_);
+    CallIC(stub.GetCode(isolate()), expr->BinaryOperationFeedbackId());
+    patch_site.EmitPatchInfo();
+  }
+  __ B(&done);
 
-  __ bind(&smi_case);
-  // Smi case. This code works the same way as the smi-smi case in the type
+  __ Bind(&both_smis);
+  // Smi case. This code works in the same way as the smi-smi case in the type
   // recording binary operation stub, see
+  // BinaryOpStub::GenerateSmiSmiOperation for comments.
+  // TODO(all): That doesn't exist any more. Where are the comments?
+  //
+  // The set of operations that needs to be supported here is controlled by
+  // FullCodeGenerator::ShouldInlineSmiCase().
   switch (op) {
     case Token::SAR:
-      __ GetLeastBitsFromSmi(scratch1, right, 5);
-      __ mov(right, Operand(left, ASR, scratch1));
-      __ bic(right, right, Operand(kSmiTagMask));
+      __ Ubfx(right, right, kSmiShift, 5);
+      __ Asr(result, left, right);
+      __ Bic(result, result, kSmiShiftMask);
       break;
-    case Token::SHL: {
-      __ SmiUntag(scratch1, left);
-      __ GetLeastBitsFromSmi(scratch2, right, 5);
-      __ mov(scratch1, Operand(scratch1, LSL, scratch2));
-      __ TrySmiTag(right, scratch1, &stub_call);
+    case Token::SHL:
+      __ Ubfx(right, right, kSmiShift, 5);
+      __ Lsl(result, left, right);
       break;
-    }
     case Token::SHR: {
-      __ SmiUntag(scratch1, left);
-      __ GetLeastBitsFromSmi(scratch2, right, 5);
-      __ mov(scratch1, Operand(scratch1, LSR, scratch2));
-      __ tst(scratch1, Operand(0xc0000000));
-      __ b(ne, &stub_call);
-      __ SmiTag(right, scratch1);
+      Label right_not_zero;
+      __ Cbnz(right, &right_not_zero);
+      __ Tbnz(left, kXSignBit, &stub_call);
+      __ Bind(&right_not_zero);
+      __ Ubfx(right, right, kSmiShift, 5);
+      __ Lsr(result, left, right);
+      __ Bic(result, result, kSmiShiftMask);
       break;
     }
     case Token::ADD:
-      __ add(scratch1, left, Operand(right), SetCC);
-      __ b(vs, &stub_call);
-      __ mov(right, scratch1);
+      __ Adds(x10, left, right);
+      __ B(vs, &stub_call);
+      __ Mov(result, x10);
       break;
     case Token::SUB:
-      __ sub(scratch1, left, Operand(right), SetCC);
-      __ b(vs, &stub_call);
-      __ mov(right, scratch1);
+      __ Subs(x10, left, right);
+      __ B(vs, &stub_call);
+      __ Mov(result, x10);
       break;
     case Token::MUL: {
-      __ SmiUntag(ip, right);
-      __ smull(scratch1, scratch2, left, ip);
-      __ mov(ip, Operand(scratch1, ASR, 31));
-      __ cmp(ip, Operand(scratch2));
-      __ b(ne, &stub_call);
-      __ cmp(scratch1, Operand::Zero());
-      __ mov(right, Operand(scratch1), LeaveCC, ne);
-      __ b(ne, &done);
-      __ add(scratch2, right, Operand(left), SetCC);
-      __ mov(right, Operand(Smi::FromInt(0)), LeaveCC, pl);
-      __ b(mi, &stub_call);
+      Label not_minus_zero, done;
+      __ Smulh(x10, left, right);
+      __ Cbnz(x10, &not_minus_zero);
+      __ Eor(x11, left, right);
+      __ Tbnz(x11, kXSignBit, &stub_call);
+      STATIC_ASSERT(kSmiTag == 0);
+      __ Mov(result, x10);
+      __ B(&done);
+      __ Bind(&not_minus_zero);
+      __ Cls(x11, x10);
+      __ Cmp(x11, kXRegSize - kSmiShift);
+      __ B(lt, &stub_call);
+      __ SmiTag(result, x10);
+      __ Bind(&done);
       break;
     }
     case Token::BIT_OR:
-      __ orr(right, left, Operand(right));
+      __ Orr(result, left, right);
       break;
     case Token::BIT_AND:
-      __ and_(right, left, Operand(right));
+      __ And(result, left, right);
       break;
     case Token::BIT_XOR:
-      __ eor(right, left, Operand(right));
+      __ Eor(result, left, right);
       break;
     default:
       UNREACHABLE();
   }
 
-  __ bind(&done);
-  context()->Plug(r0);
+  __ Bind(&done);
+  context()->Plug(x0);
 }
 
 
 void FullCodeGenerator::EmitBinaryOp(BinaryOperation* expr,
                                      Token::Value op,
                                      OverwriteMode mode) {
-  __ pop(r1);
+  __ Pop(x1);
   BinaryOpICStub stub(op, mode);
-  JumpPatchSite patch_site(masm_);    // unbound, signals no inlined smi code.
-  CallIC(stub.GetCode(isolate()), NOT_CONTEXTUAL,
-         expr->BinaryOperationFeedbackId());
-  patch_site.EmitPatchInfo();
-  context()->Plug(r0);
+  JumpPatchSite patch_site(masm_);    // Unbound, signals no inlined smi code.
+  {
+    Assembler::BlockConstPoolScope scope(masm_);
+    CallIC(stub.GetCode(isolate()), expr->BinaryOperationFeedbackId());
+    patch_site.EmitPatchInfo();
+  }
+  context()->Plug(x0);
 }
 
 
 void FullCodeGenerator::EmitAssignment(Expression* expr) {
-  // Invalid left-hand sides are rewritten by the parser to have a 'throw
+  // Invalid left-hand sides are rewritten to have a 'throw
   // ReferenceError' on the left-hand side.
   if (!expr->IsValidLeftHandSide()) {
     VisitForEffect(expr);
     return;
   }
 
   // Left-hand side can only be a property, a global or a (parameter or local)
   // slot.
   enum LhsKind { VARIABLE, NAMED_PROPERTY, KEYED_PROPERTY };
   LhsKind assign_type = VARIABLE;
   Property* prop = expr->AsProperty();
   if (prop != NULL) {
     assign_type = (prop->key()->IsPropertyName())
         ? NAMED_PROPERTY
         : KEYED_PROPERTY;
   }
 
   switch (assign_type) {
     case VARIABLE: {
       Variable* var = expr->AsVariableProxy()->var();
       EffectContext context(this);
       EmitVariableAssignment(var, Token::ASSIGN);
       break;
     }
     case NAMED_PROPERTY: {
-      __ push(r0);  // Preserve value.
+      __ Push(x0);  // Preserve value.
       VisitForAccumulatorValue(prop->obj());
-      __ mov(r1, r0);
-      __ pop(r0);  // Restore value.
-      __ mov(r2, Operand(prop->key()->AsLiteral()->value()));
-      CallStoreIC(NOT_CONTEXTUAL);
+      // TODO(all): We could introduce a VisitForRegValue(reg, expr) to avoid
+      // this copy.
+      __ Mov(x1, x0);
+      __ Pop(x0);  // Restore value.
+      __ Mov(x2, Operand(prop->key()->AsLiteral()->value()));
+      CallStoreIC();
       break;
     }
     case KEYED_PROPERTY: {
-      __ push(r0);  // Preserve value.
+      __ Push(x0);  // Preserve value.
       VisitForStackValue(prop->obj());
       VisitForAccumulatorValue(prop->key());
-      __ mov(r1, r0);
-      __ Pop(r0, r2);  // r0 = restored value.
+      __ Mov(x1, x0);
+      __ Pop(x2, x0);
       Handle<Code> ic = is_classic_mode()
           ? isolate()->builtins()->KeyedStoreIC_Initialize()
           : isolate()->builtins()->KeyedStoreIC_Initialize_Strict();
       CallIC(ic);
       break;
     }
   }
-  context()->Plug(r0);
+  context()->Plug(x0);
+}
+
+
+void FullCodeGenerator::EmitStoreToStackLocalOrContextSlot(
+    Variable* var, MemOperand location) {
+  __ Str(result_register(), location);
+  if (var->IsContextSlot()) {
+    // RecordWrite may destroy all its register arguments.
+    __ Mov(x10, result_register());
+    int offset = Context::SlotOffset(var->index());
+    __ RecordWriteContextSlot(
+        x1, offset, x10, x11, kLRHasBeenSaved, kDontSaveFPRegs);
+  }
+}
+
+
+void FullCodeGenerator::EmitCallStoreContextSlot(
+    Handle<String> name, LanguageMode mode) {
+  __ Mov(x11, Operand(name));
+  __ Mov(x10, Operand(Smi::FromInt(mode)));
+  // jssp[0]  : mode.
+  // jssp[8]  : name.
+  // jssp[16] : context.
+  // jssp[24] : value.
+  __ Push(x0, cp, x11, x10);
+  __ CallRuntime(Runtime::kStoreContextSlot, 4);
 }
 
 
 void FullCodeGenerator::EmitVariableAssignment(Variable* var,
                                                Token::Value op) {
+  ASM_LOCATION("FullCodeGenerator::EmitVariableAssignment");
   if (var->IsUnallocated()) {
     // Global var, const, or let.
-    __ mov(r2, Operand(var->name()));
-    __ ldr(r1, GlobalObjectOperand());
-    CallStoreIC(CONTEXTUAL);
+    __ Mov(x2, Operand(var->name()));
+    __ Ldr(x1, GlobalObjectMemOperand());
+    CallStoreIC();
+
   } else if (op == Token::INIT_CONST) {
     // Const initializers need a write barrier.
     ASSERT(!var->IsParameter());  // No const parameters.
-    if (var->IsStackLocal()) {
-      __ ldr(r1, StackOperand(var));
-      __ CompareRoot(r1, Heap::kTheHoleValueRootIndex);
-      __ str(result_register(), StackOperand(var), eq);
+    if (var->IsLookupSlot()) {
+      __ Push(x0);
+      __ Mov(x0, Operand(var->name()));
+      __ Push(cp, x0);  // Context and name.
+      __ CallRuntime(Runtime::kInitializeConstContextSlot, 3);
     } else {
-      ASSERT(var->IsContextSlot() || var->IsLookupSlot());
-      // Like var declarations, const declarations are hoisted to function
-      // scope.  However, unlike var initializers, const initializers are
-      // able to drill a hole to that function context, even from inside a
-      // 'with' context.  We thus bypass the normal static scope lookup for
-      // var->IsContextSlot().
-      __ push(r0);
-      __ mov(r0, Operand(var->name()));
-      __ Push(cp, r0);  // Context and name.
-      __ CallRuntime(Runtime::kInitializeConstContextSlot, 3);
+      ASSERT(var->IsStackLocal() || var->IsContextSlot());
+      Label skip;
+      MemOperand location = VarOperand(var, x1);
+      __ Ldr(x10, location);
+      __ JumpIfNotRoot(x10, Heap::kTheHoleValueRootIndex, &skip);
+      EmitStoreToStackLocalOrContextSlot(var, location);
+      __ Bind(&skip);
     }
 
   } else if (var->mode() == LET && op != Token::INIT_LET) {
     // Non-initializing assignment to let variable needs a write barrier.
     if (var->IsLookupSlot()) {
-      __ push(r0);  // Value.
-      __ mov(r1, Operand(var->name()));
-      __ mov(r0, Operand(Smi::FromInt(language_mode())));
-      __ Push(cp, r1, r0);  // Context, name, strict mode.
-      __ CallRuntime(Runtime::kStoreContextSlot, 4);
+      EmitCallStoreContextSlot(var->name(), language_mode());
     } else {
       ASSERT(var->IsStackAllocated() || var->IsContextSlot());
       Label assign;
-      MemOperand location = VarOperand(var, r1);
-      __ ldr(r3, location);
-      __ CompareRoot(r3, Heap::kTheHoleValueRootIndex);
-      __ b(ne, &assign);
-      __ mov(r3, Operand(var->name()));
-      __ push(r3);
+      MemOperand location = VarOperand(var, x1);
+      __ Ldr(x10, location);
+      __ JumpIfNotRoot(x10, Heap::kTheHoleValueRootIndex, &assign);
+      __ Mov(x10, Operand(var->name()));
+      __ Push(x10);
       __ CallRuntime(Runtime::kThrowReferenceError, 1);
       // Perform the assignment.
-      __ bind(&assign);
-      __ str(result_register(), location);
-      if (var->IsContextSlot()) {
-        // RecordWrite may destroy all its register arguments.
-        __ mov(r3, result_register());
-        int offset = Context::SlotOffset(var->index());
-        __ RecordWriteContextSlot(
-            r1, offset, r3, r2, kLRHasBeenSaved, kDontSaveFPRegs);
-      }
+      __ Bind(&assign);
+      EmitStoreToStackLocalOrContextSlot(var, location);
     }
 
   } else if (!var->is_const_mode() || op == Token::INIT_CONST_HARMONY) {
     // Assignment to var or initializing assignment to let/const
     // in harmony mode.
-    if (var->IsStackAllocated() || var->IsContextSlot()) {
-      MemOperand location = VarOperand(var, r1);
-      if (generate_debug_code_ && op == Token::INIT_LET) {
-        // Check for an uninitialized let binding.
-        __ ldr(r2, location);
-        __ CompareRoot(r2, Heap::kTheHoleValueRootIndex);
+    if (var->IsLookupSlot()) {
+      EmitCallStoreContextSlot(var->name(), language_mode());
+    } else {
+      ASSERT(var->IsStackAllocated() || var->IsContextSlot());
+      MemOperand location = VarOperand(var, x1);
+      if (FLAG_debug_code && op == Token::INIT_LET) {
+        __ Ldr(x10, location);
+        __ CompareRoot(x10, Heap::kTheHoleValueRootIndex);
         __ Check(eq, kLetBindingReInitialization);
       }
-      // Perform the assignment.
-      __ str(r0, location);
-      if (var->IsContextSlot()) {
-        __ mov(r3, r0);
-        int offset = Context::SlotOffset(var->index());
-        __ RecordWriteContextSlot(
-            r1, offset, r3, r2, kLRHasBeenSaved, kDontSaveFPRegs);
-      }
-    } else {
-      ASSERT(var->IsLookupSlot());
-      __ push(r0);  // Value.
-      __ mov(r1, Operand(var->name()));
-      __ mov(r0, Operand(Smi::FromInt(language_mode())));
-      __ Push(cp, r1, r0);  // Context, name, strict mode.
-      __ CallRuntime(Runtime::kStoreContextSlot, 4);
+      EmitStoreToStackLocalOrContextSlot(var, location);
     }
   }
   // Non-initializing assignments to consts are ignored.
 }
 
 
 void FullCodeGenerator::EmitNamedPropertyAssignment(Assignment* expr) {
+  ASM_LOCATION("FullCodeGenerator::EmitNamedPropertyAssignment");
   // Assignment to a property, using a named store IC.
   Property* prop = expr->target()->AsProperty();
   ASSERT(prop != NULL);
   ASSERT(prop->key()->AsLiteral() != NULL);
 
   // Record source code position before IC call.
   SetSourcePosition(expr->position());
-  __ mov(r2, Operand(prop->key()->AsLiteral()->value()));
-  __ pop(r1);
+  __ Mov(x2, Operand(prop->key()->AsLiteral()->value()));
+  __ Pop(x1);
 
-  CallStoreIC(NOT_CONTEXTUAL, expr->AssignmentFeedbackId());
+  CallStoreIC(expr->AssignmentFeedbackId());
 
   PrepareForBailoutForId(expr->AssignmentId(), TOS_REG);
-  context()->Plug(r0);
+  context()->Plug(x0);
 }
 
 
 void FullCodeGenerator::EmitKeyedPropertyAssignment(Assignment* expr) {
+  ASM_LOCATION("FullCodeGenerator::EmitKeyedPropertyAssignment");
   // Assignment to a property, using a keyed store IC.
 
   // Record source code position before IC call.
   SetSourcePosition(expr->position());
-  __ Pop(r2, r1);  // r1 = key.
+  // TODO(all): Could we pass this in registers rather than on the stack?
+  __ Pop(x1, x2);  // Key and object holding the property.
 
   Handle<Code> ic = is_classic_mode()
       ? isolate()->builtins()->KeyedStoreIC_Initialize()
       : isolate()->builtins()->KeyedStoreIC_Initialize_Strict();
-  CallIC(ic, NOT_CONTEXTUAL, expr->AssignmentFeedbackId());
+  CallIC(ic, expr->AssignmentFeedbackId());
 
   PrepareForBailoutForId(expr->AssignmentId(), TOS_REG);
-  context()->Plug(r0);
+  context()->Plug(x0);
 }
 
 
 void FullCodeGenerator::VisitProperty(Property* expr) {
   Comment cmnt(masm_, "[ Property");
   Expression* key = expr->key();
 
   if (key->IsPropertyName()) {
     VisitForAccumulatorValue(expr->obj());
     EmitNamedPropertyLoad(expr);
     PrepareForBailoutForId(expr->LoadId(), TOS_REG);
-    context()->Plug(r0);
+    context()->Plug(x0);
   } else {
     VisitForStackValue(expr->obj());
     VisitForAccumulatorValue(expr->key());
-    __ pop(r1);
+    __ Pop(x1);
     EmitKeyedPropertyLoad(expr);
-    context()->Plug(r0);
+    context()->Plug(x0);
   }
 }
 
 
 void FullCodeGenerator::CallIC(Handle<Code> code,
-                               ContextualMode mode,
                                TypeFeedbackId ast_id) {
   ic_total_count_++;
   // All calls must have a predictable size in full-codegen code to ensure that
   // the debugger can patch them correctly.
-  ASSERT(mode != CONTEXTUAL || ast_id.IsNone());
-  __ Call(code, RelocInfo::CODE_TARGET, ast_id, al,
-          NEVER_INLINE_TARGET_ADDRESS);
+  __ Call(code, RelocInfo::CODE_TARGET, ast_id);
 }
 
-void FullCodeGenerator::EmitCallWithIC(Call* expr,
-                                       Handle<Object> name,
-                                       ContextualMode mode) {
-  // Code common for calls using the IC.
+
+// Code common for calls using the IC.
+void FullCodeGenerator::EmitCallWithIC(Call* expr) {
+  ASM_LOCATION("EmitCallWithIC");
+
+  Expression* callee = expr->expression();
   ZoneList<Expression*>* args = expr->arguments();
   int arg_count = args->length();
+
+  CallFunctionFlags flags;
+  // Get the target function.
+  if (callee->IsVariableProxy()) {
+    { StackValueContext context(this);
+      EmitVariableLoad(callee->AsVariableProxy());
+      PrepareForBailout(callee, NO_REGISTERS);
+    }
+    // Push undefined as receiver. This is patched in the method prologue if it
+    // is a classic mode method.
+    __ Push(isolate()->factory()->undefined_value());
+    flags = NO_CALL_FUNCTION_FLAGS;
+  } else {
+    // Load the function from the receiver.
+    ASSERT(callee->IsProperty());
+    __ Peek(x0, 0);
+    EmitNamedPropertyLoad(callee->AsProperty());
+    PrepareForBailoutForId(callee->AsProperty()->LoadId(), TOS_REG);
+    // Push the target function under the receiver.
+    __ Pop(x10);
+    __ Push(x0, x10);
+    flags = CALL_AS_METHOD;
+  }
+
+  // Load the arguments.
   { PreservePositionScope scope(masm()->positions_recorder());
     for (int i = 0; i < arg_count; i++) {
       VisitForStackValue(args->at(i));
     }
-    __ mov(r2, Operand(name));
   }
+
   // Record source position for debugger.
   SetSourcePosition(expr->position());
-  // Call the IC initialization code.
-  Handle<Code> ic = isolate()->stub_cache()->ComputeCallInitialize(arg_count);
-  TypeFeedbackId ast_id = mode == CONTEXTUAL
-      ? TypeFeedbackId::None()
-      : expr->CallFeedbackId();
-  CallIC(ic, mode, ast_id);
+  CallFunctionStub stub(arg_count, flags);
+  __ Peek(x1, (arg_count + 1) * kPointerSize);
+  __ CallStub(&stub);
+
   RecordJSReturnSite(expr);
+
   // Restore context register.
-  __ ldr(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
-  context()->Plug(r0);
+  __ Ldr(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
+
+  context()->DropAndPlug(1, x0);
 }
 
 
+// Code common for calls using the IC.
 void FullCodeGenerator::EmitKeyedCallWithIC(Call* expr,
                                             Expression* key) {
   // Load the key.
   VisitForAccumulatorValue(key);
 
-  // Swap the name of the function and the receiver on the stack to follow
-  // the calling convention for call ICs.
-  __ pop(r1);
-  __ push(r0);
-  __ push(r1);
-
-  // Code common for calls using the IC.
+  Expression* callee = expr->expression();
   ZoneList<Expression*>* args = expr->arguments();
   int arg_count = args->length();
+
+  // Load the function from the receiver.
+  ASSERT(callee->IsProperty());
+  __ Peek(x1, 0);
+  EmitKeyedPropertyLoad(callee->AsProperty());
+  PrepareForBailoutForId(callee->AsProperty()->LoadId(), TOS_REG);
+
+  // Push the target function under the receiver.
+  __ Pop(x10);
+  __ Push(x0, x10);
+
   { PreservePositionScope scope(masm()->positions_recorder());
     for (int i = 0; i < arg_count; i++) {
       VisitForStackValue(args->at(i));
     }
   }
+
   // Record source position for debugger.
   SetSourcePosition(expr->position());
-  // Call the IC initialization code.
-  Handle<Code> ic =
-      isolate()->stub_cache()->ComputeKeyedCallInitialize(arg_count);
-  __ ldr(r2, MemOperand(sp, (arg_count + 1) * kPointerSize));  // Key.
-  CallIC(ic, NOT_CONTEXTUAL, expr->CallFeedbackId());
+  CallFunctionStub stub(arg_count, CALL_AS_METHOD);
+  __ Peek(x1, (arg_count + 1) * kPointerSize);
+  __ CallStub(&stub);
+
   RecordJSReturnSite(expr);
   // Restore context register.
-  __ ldr(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
-  context()->DropAndPlug(1, r0);  // Drop the key still on the stack.
+  __ Ldr(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
+
+  context()->DropAndPlug(1, x0);
 }
 
 
 void FullCodeGenerator::EmitCallWithStub(Call* expr) {
   // Code common for calls using the call stub.
   ZoneList<Expression*>* args = expr->arguments();
   int arg_count = args->length();
   { PreservePositionScope scope(masm()->positions_recorder());
     for (int i = 0; i < arg_count; i++) {
       VisitForStackValue(args->at(i));
     }
   }
   // Record source position for debugger.
   SetSourcePosition(expr->position());
 
   Handle<Object> uninitialized =
-      TypeFeedbackCells::UninitializedSentinel(isolate());
-  Handle<Cell> cell = isolate()->factory()->NewCell(uninitialized);
-  RecordTypeFeedbackCell(expr->CallFeedbackId(), cell);
-  __ mov(r2, Operand(cell));
+      TypeFeedbackInfo::UninitializedSentinel(isolate());
+  StoreFeedbackVectorSlot(expr->CallFeedbackSlot(), uninitialized);
+  __ LoadObject(x2, FeedbackVector());
+  __ Mov(x3, Operand(Smi::FromInt(expr->CallFeedbackSlot())));
 
   // Record call targets in unoptimized code.
   CallFunctionStub stub(arg_count, RECORD_CALL_TARGET);
-  __ ldr(r1, MemOperand(sp, (arg_count + 1) * kPointerSize));
-  __ CallStub(&stub, expr->CallFeedbackId());
+  __ Peek(x1, (arg_count + 1) * kXRegSizeInBytes);
+  __ CallStub(&stub);
   RecordJSReturnSite(expr);
   // Restore context register.
-  __ ldr(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
-  context()->DropAndPlug(1, r0);
+  __ Ldr(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
+  context()->DropAndPlug(1, x0);
 }
 
 
 void FullCodeGenerator::EmitResolvePossiblyDirectEval(int arg_count) {
-  // r4: copy of the first argument or undefined if it doesn't exist.
+  ASM_LOCATION("FullCodeGenerator::EmitResolvePossiblyDirectEval");
+  // Prepare to push a copy of the first argument or undefined if it doesn't
+  // exist.
   if (arg_count > 0) {
-    __ ldr(r4, MemOperand(sp, arg_count * kPointerSize));
+    __ Peek(x10, arg_count * kXRegSizeInBytes);
   } else {
-    __ LoadRoot(r4, Heap::kUndefinedValueRootIndex);
+    __ LoadRoot(x10, Heap::kUndefinedValueRootIndex);
   }
 
-  // r3: the receiver of the enclosing function.
+  // Prepare to push the receiver of the enclosing function.
   int receiver_offset = 2 + info_->scope()->num_parameters();
-  __ ldr(r3, MemOperand(fp, receiver_offset * kPointerSize));
+  __ Ldr(x11, MemOperand(fp, receiver_offset * kPointerSize));
 
-  // r2: the language mode.
-  __ mov(r2, Operand(Smi::FromInt(language_mode())));
+  // Push.
+  __ Push(x10, x11);
 
-  // r1: the start position of the scope the calls resides in.
-  __ mov(r1, Operand(Smi::FromInt(scope()->start_position())));
+  // Prepare to push the language mode.
+  __ Mov(x10, Operand(Smi::FromInt(language_mode())));
+  // Prepare to push the start position of the scope the calls resides in.
+  __ Mov(x11, Operand(Smi::FromInt(scope()->start_position())));
+
+  // Push.
+  __ Push(x10, x11);
 
   // Do the runtime call.
-  __ Push(r4, r3, r2, r1);
   __ CallRuntime(Runtime::kResolvePossiblyDirectEval, 5);
 }
 
 
 void FullCodeGenerator::VisitCall(Call* expr) {
 #ifdef DEBUG
   // We want to verify that RecordJSReturnSite gets called on all paths
   // through this function.  Avoid early returns.
   expr->return_is_recorded_ = false;
 #endif
 
   Comment cmnt(masm_, "[ Call");
   Expression* callee = expr->expression();
   Call::CallType call_type = expr->GetCallType(isolate());
 
   if (call_type == Call::POSSIBLY_EVAL_CALL) {
     // In a call to eval, we first call %ResolvePossiblyDirectEval to
     // resolve the function we need to call and the receiver of the
     // call.  Then we call the resolved function using the given
     // arguments.
     ZoneList<Expression*>* args = expr->arguments();
     int arg_count = args->length();
 
-    { PreservePositionScope pos_scope(masm()->positions_recorder());
+    {
+      PreservePositionScope pos_scope(masm()->positions_recorder());
       VisitForStackValue(callee);
-      __ LoadRoot(r2, Heap::kUndefinedValueRootIndex);
-      __ push(r2);  // Reserved receiver slot.
+      __ LoadRoot(x10, Heap::kUndefinedValueRootIndex);
+      __ Push(x10);  // Reserved receiver slot.
 
       // Push the arguments.
       for (int i = 0; i < arg_count; i++) {
         VisitForStackValue(args->at(i));
       }
 
       // Push a copy of the function (found below the arguments) and
       // resolve eval.
-      __ ldr(r1, MemOperand(sp, (arg_count + 1) * kPointerSize));
-      __ push(r1);
+      __ Peek(x10, (arg_count + 1) * kPointerSize);
+      __ Push(x10);
       EmitResolvePossiblyDirectEval(arg_count);
 
-      // The runtime call returns a pair of values in r0 (function) and
-      // r1 (receiver). Touch up the stack with the right values.
-      __ str(r0, MemOperand(sp, (arg_count + 1) * kPointerSize));
-      __ str(r1, MemOperand(sp, arg_count * kPointerSize));
+      // The runtime call returns a pair of values in x0 (function) and
+      // x1 (receiver). Touch up the stack with the right values.
+      __ PokePair(x1, x0, arg_count * kPointerSize);
     }
 
     // Record source position for debugger.
     SetSourcePosition(expr->position());
+
+    // Call the evaluated function.
     CallFunctionStub stub(arg_count, NO_CALL_FUNCTION_FLAGS);
-    __ ldr(r1, MemOperand(sp, (arg_count + 1) * kPointerSize));
+    __ Peek(x1, (arg_count + 1) * kXRegSizeInBytes);
     __ CallStub(&stub);
     RecordJSReturnSite(expr);
     // Restore context register.
-    __ ldr(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
-    context()->DropAndPlug(1, r0);
+    __ Ldr(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
+    context()->DropAndPlug(1, x0);
+
   } else if (call_type == Call::GLOBAL_CALL) {
-    // Push global object as receiver for the call IC.
-    __ ldr(r0, GlobalObjectOperand());
-    __ push(r0);
-    VariableProxy* proxy = callee->AsVariableProxy();
-    EmitCallWithIC(expr, proxy->name(), CONTEXTUAL);
+    EmitCallWithIC(expr);
+
   } else if (call_type == Call::LOOKUP_SLOT_CALL) {
     // Call to a lookup slot (dynamically introduced variable).
     VariableProxy* proxy = callee->AsVariableProxy();
     Label slow, done;
 
     { PreservePositionScope scope(masm()->positions_recorder());
       // Generate code for loading from variables potentially shadowed
       // by eval-introduced variables.
       EmitDynamicLookupFastCase(proxy->var(), NOT_INSIDE_TYPEOF, &slow, &done);
     }
 
-    __ bind(&slow);
-    // Call the runtime to find the function to call (returned in r0)
-    // and the object holding it (returned in edx).
-    ASSERT(!context_register().is(r2));
-    __ mov(r2, Operand(proxy->name()));
-    __ Push(context_register(), r2);
+    __ Bind(&slow);
+    // Call the runtime to find the function to call (returned in x0)
+    // and the object holding it (returned in x1).
+    __ Push(context_register());
+    __ Mov(x10, Operand(proxy->name()));
+    __ Push(x10);
     __ CallRuntime(Runtime::kLoadContextSlot, 2);
-    __ Push(r0, r1);  // Function, receiver.
+    __ Push(x0, x1);  // Receiver, function.
 
     // If fast case code has been generated, emit code to push the
     // function and receiver and have the slow path jump around this
     // code.
     if (done.is_linked()) {
       Label call;
-      __ b(&call);
-      __ bind(&done);
+      __ B(&call);
+      __ Bind(&done);
       // Push function.
-      __ push(r0);
+      __ Push(x0);
       // The receiver is implicitly the global receiver. Indicate this
-      // by passing the hole to the call function stub.
-      __ LoadRoot(r1, Heap::kUndefinedValueRootIndex);
-      __ push(r1);
-      __ bind(&call);
+      // by passing the undefined to the call function stub.
+      __ LoadRoot(x1, Heap::kUndefinedValueRootIndex);
+      __ Push(x1);
+      __ Bind(&call);
     }
 
     // The receiver is either the global receiver or an object found
     // by LoadContextSlot.
     EmitCallWithStub(expr);
   } else if (call_type == Call::PROPERTY_CALL) {
     Property* property = callee->AsProperty();
     { PreservePositionScope scope(masm()->positions_recorder());
       VisitForStackValue(property->obj());
     }
     if (property->key()->IsPropertyName()) {
-      EmitCallWithIC(expr,
-                     property->key()->AsLiteral()->value(),
-                     NOT_CONTEXTUAL);
+      EmitCallWithIC(expr);
     } else {
       EmitKeyedCallWithIC(expr, property->key());
     }
+
   } else {
     ASSERT(call_type == Call::OTHER_CALL);
     // Call to an arbitrary expression not handled specially above.
     { PreservePositionScope scope(masm()->positions_recorder());
       VisitForStackValue(callee);
     }
-    __ LoadRoot(r1, Heap::kUndefinedValueRootIndex);
-    __ push(r1);
+    __ LoadRoot(x1, Heap::kUndefinedValueRootIndex);
+    __ Push(x1);
     // Emit function call.
     EmitCallWithStub(expr);
   }
 
 #ifdef DEBUG
   // RecordJSReturnSite should have been called.
   ASSERT(expr->return_is_recorded_);
 #endif
 }
 
@@ skipping 13 matching lines @@
   ZoneList<Expression*>* args = expr->arguments();
   int arg_count = args->length();
   for (int i = 0; i < arg_count; i++) {
     VisitForStackValue(args->at(i));
   }
 
   // Call the construct call builtin that handles allocation and
   // constructor invocation.
   SetSourcePosition(expr->position());
 
-  // Load function and argument count into r1 and r0.
-  __ mov(r0, Operand(arg_count));
-  __ ldr(r1, MemOperand(sp, arg_count * kPointerSize));
+  // Load function and argument count into x1 and x0.
+  __ Mov(x0, arg_count);
+  __ Peek(x1, arg_count * kXRegSizeInBytes);
 
   // Record call targets in unoptimized code.
   Handle<Object> uninitialized =
-      TypeFeedbackCells::UninitializedSentinel(isolate());
-  Handle<Cell> cell = isolate()->factory()->NewCell(uninitialized);
-  RecordTypeFeedbackCell(expr->CallNewFeedbackId(), cell);
-  __ mov(r2, Operand(cell));
+      TypeFeedbackInfo::UninitializedSentinel(isolate());
+  StoreFeedbackVectorSlot(expr->CallNewFeedbackSlot(), uninitialized);
+  __ LoadObject(x2, FeedbackVector());
+  __ Mov(x3, Operand(Smi::FromInt(expr->CallNewFeedbackSlot())));
 
   CallConstructStub stub(RECORD_CALL_TARGET);
   __ Call(stub.GetCode(isolate()), RelocInfo::CONSTRUCT_CALL);
   PrepareForBailoutForId(expr->ReturnId(), TOS_REG);
-  context()->Plug(r0);
+  context()->Plug(x0);
 }
 
 
 void FullCodeGenerator::EmitIsSmi(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT(args->length() == 1);
 
   VisitForAccumulatorValue(args->at(0));
 
   Label materialize_true, materialize_false;
   Label* if_true = NULL;
   Label* if_false = NULL;
   Label* fall_through = NULL;
   context()->PrepareTest(&materialize_true, &materialize_false,
                          &if_true, &if_false, &fall_through);
 
   PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
-  __ SmiTst(r0);
-  Split(eq, if_true, if_false, fall_through);
+  __ TestAndSplit(x0, kSmiTagMask, if_true, if_false, fall_through);
 
   context()->Plug(if_true, if_false);
 }
 
 
 void FullCodeGenerator::EmitIsNonNegativeSmi(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT(args->length() == 1);
 
   VisitForAccumulatorValue(args->at(0));
 
   Label materialize_true, materialize_false;
   Label* if_true = NULL;
   Label* if_false = NULL;
   Label* fall_through = NULL;
   context()->PrepareTest(&materialize_true, &materialize_false,
                          &if_true, &if_false, &fall_through);
 
   PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
-  __ NonNegativeSmiTst(r0);
-  Split(eq, if_true, if_false, fall_through);
+  __ TestAndSplit(x0, kSmiTagMask | (0x80000000UL << kSmiShift), if_true,
+                  if_false, fall_through);
 
   context()->Plug(if_true, if_false);
 }
 
 
 void FullCodeGenerator::EmitIsObject(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT(args->length() == 1);
 
   VisitForAccumulatorValue(args->at(0));
 
   Label materialize_true, materialize_false;
   Label* if_true = NULL;
   Label* if_false = NULL;
   Label* fall_through = NULL;
   context()->PrepareTest(&materialize_true, &materialize_false,
                          &if_true, &if_false, &fall_through);
 
-  __ JumpIfSmi(r0, if_false);
-  __ LoadRoot(ip, Heap::kNullValueRootIndex);
-  __ cmp(r0, ip);
-  __ b(eq, if_true);
-  __ ldr(r2, FieldMemOperand(r0, HeapObject::kMapOffset));
+  __ JumpIfSmi(x0, if_false);
+  __ JumpIfRoot(x0, Heap::kNullValueRootIndex, if_true);
+  __ Ldr(x10, FieldMemOperand(x0, HeapObject::kMapOffset));
   // Undetectable objects behave like undefined when tested with typeof.
-  __ ldrb(r1, FieldMemOperand(r2, Map::kBitFieldOffset));
-  __ tst(r1, Operand(1 << Map::kIsUndetectable));
-  __ b(ne, if_false);
-  __ ldrb(r1, FieldMemOperand(r2, Map::kInstanceTypeOffset));
-  __ cmp(r1, Operand(FIRST_NONCALLABLE_SPEC_OBJECT_TYPE));
-  __ b(lt, if_false);
-  __ cmp(r1, Operand(LAST_NONCALLABLE_SPEC_OBJECT_TYPE));
+  __ Ldrb(x11, FieldMemOperand(x10, Map::kBitFieldOffset));
+  __ Tbnz(x11, Map::kIsUndetectable, if_false);
+  __ Ldrb(x12, FieldMemOperand(x10, Map::kInstanceTypeOffset));
+  __ Cmp(x12, FIRST_NONCALLABLE_SPEC_OBJECT_TYPE);
+  __ B(lt, if_false);
+  __ Cmp(x12, LAST_NONCALLABLE_SPEC_OBJECT_TYPE);
   PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
   Split(le, if_true, if_false, fall_through);
 
   context()->Plug(if_true, if_false);
 }
 
 
 void FullCodeGenerator::EmitIsSpecObject(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT(args->length() == 1);
 
   VisitForAccumulatorValue(args->at(0));
 
   Label materialize_true, materialize_false;
   Label* if_true = NULL;
   Label* if_false = NULL;
   Label* fall_through = NULL;
   context()->PrepareTest(&materialize_true, &materialize_false,
                          &if_true, &if_false, &fall_through);
 
-  __ JumpIfSmi(r0, if_false);
-  __ CompareObjectType(r0, r1, r1, FIRST_SPEC_OBJECT_TYPE);
+  __ JumpIfSmi(x0, if_false);
+  __ CompareObjectType(x0, x10, x11, FIRST_SPEC_OBJECT_TYPE);
   PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
   Split(ge, if_true, if_false, fall_through);
 
   context()->Plug(if_true, if_false);
 }
 
 
 void FullCodeGenerator::EmitIsUndetectableObject(CallRuntime* expr) {
+  ASM_LOCATION("FullCodeGenerator::EmitIsUndetectableObject");
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT(args->length() == 1);
 
   VisitForAccumulatorValue(args->at(0));
 
   Label materialize_true, materialize_false;
   Label* if_true = NULL;
   Label* if_false = NULL;
   Label* fall_through = NULL;
   context()->PrepareTest(&materialize_true, &materialize_false,
                          &if_true, &if_false, &fall_through);
 
-  __ JumpIfSmi(r0, if_false);
-  __ ldr(r1, FieldMemOperand(r0, HeapObject::kMapOffset));
-  __ ldrb(r1, FieldMemOperand(r1, Map::kBitFieldOffset));
-  __ tst(r1, Operand(1 << Map::kIsUndetectable));
+  __ JumpIfSmi(x0, if_false);
+  __ Ldr(x10, FieldMemOperand(x0, HeapObject::kMapOffset));
+  __ Ldrb(x11, FieldMemOperand(x10, Map::kBitFieldOffset));
+  __ Tst(x11, 1 << Map::kIsUndetectable);
   PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
   Split(ne, if_true, if_false, fall_through);
 
   context()->Plug(if_true, if_false);
 }
 
 
 void FullCodeGenerator::EmitIsStringWrapperSafeForDefaultValueOf(
     CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT(args->length() == 1);
-
   VisitForAccumulatorValue(args->at(0));
 
   Label materialize_true, materialize_false, skip_lookup;
   Label* if_true = NULL;
   Label* if_false = NULL;
   Label* fall_through = NULL;
   context()->PrepareTest(&materialize_true, &materialize_false,
                          &if_true, &if_false, &fall_through);
 
-  __ AssertNotSmi(r0);
+  Register object = x0;
+  __ AssertNotSmi(object);
 
-  __ ldr(r1, FieldMemOperand(r0, HeapObject::kMapOffset));
-  __ ldrb(ip, FieldMemOperand(r1, Map::kBitField2Offset));
-  __ tst(ip, Operand(1 << Map::kStringWrapperSafeForDefaultValueOf));
-  __ b(ne, &skip_lookup);
+  Register map = x10;
+  Register bitfield2 = x11;
+  __ Ldr(map, FieldMemOperand(object, HeapObject::kMapOffset));
+  __ Ldrb(bitfield2, FieldMemOperand(map, Map::kBitField2Offset));
+  __ Tbnz(bitfield2, Map::kStringWrapperSafeForDefaultValueOf, &skip_lookup);
 
   // Check for fast case object. Generate false result for slow case object.
-  __ ldr(r2, FieldMemOperand(r0, JSObject::kPropertiesOffset));
-  __ ldr(r2, FieldMemOperand(r2, HeapObject::kMapOffset));
-  __ LoadRoot(ip, Heap::kHashTableMapRootIndex);
-  __ cmp(r2, ip);
-  __ b(eq, if_false);
+  Register props = x12;
+  Register props_map = x12;
+  Register hash_table_map = x13;
+  __ Ldr(props, FieldMemOperand(object, JSObject::kPropertiesOffset));
+  __ Ldr(props_map, FieldMemOperand(props, HeapObject::kMapOffset));
+  __ LoadRoot(hash_table_map, Heap::kHashTableMapRootIndex);
+  __ Cmp(props_map, hash_table_map);
+  __ B(eq, if_false);
 
-  // Look for valueOf name in the descriptor array, and indicate false if
-  // found. Since we omit an enumeration index check, if it is added via a
-  // transition that shares its descriptor array, this is a false positive.
-  Label entry, loop, done;
+  // Look for valueOf name in the descriptor array, and indicate false if found.
+  // Since we omit an enumeration index check, if it is added via a transition
+  // that shares its descriptor array, this is a false positive.
+  Label loop, done;
 
   // Skip loop if no descriptors are valid.
-  __ NumberOfOwnDescriptors(r3, r1);
-  __ cmp(r3, Operand::Zero());
-  __ b(eq, &done);
+  Register descriptors = x12;
+  Register descriptors_length = x13;
+  __ NumberOfOwnDescriptors(descriptors_length, map);
+  __ Cbz(descriptors_length, &done);
 
-  __ LoadInstanceDescriptors(r1, r4);
-  // r4: descriptor array.
-  // r3: valid entries in the descriptor array.
-  __ mov(ip, Operand(DescriptorArray::kDescriptorSize));
-  __ mul(r3, r3, ip);
+  __ LoadInstanceDescriptors(map, descriptors);
+
+  // Calculate the end of the descriptor array.
+  Register descriptors_end = x14;
+  __ Mov(x15, DescriptorArray::kDescriptorSize);
+  __ Mul(descriptors_length, descriptors_length, x15);
   // Calculate location of the first key name.
-  __ add(r4, r4, Operand(DescriptorArray::kFirstOffset - kHeapObjectTag));
+  __ Add(descriptors, descriptors,
+         DescriptorArray::kFirstOffset - kHeapObjectTag);
   // Calculate the end of the descriptor array.
-  __ mov(r2, r4);
-  __ add(r2, r2, Operand::PointerOffsetFromSmiKey(r3));
+  __ Add(descriptors_end, descriptors,
+         Operand(descriptors_length, LSL, kPointerSizeLog2));
 
   // Loop through all the keys in the descriptor array. If one of these is the
   // string "valueOf" the result is false.
-  // The use of ip to store the valueOf string assumes that it is not otherwise
-  // used in the loop below.
-  __ mov(ip, Operand(isolate()->factory()->value_of_string()));
-  __ jmp(&entry);
-  __ bind(&loop);
-  __ ldr(r3, MemOperand(r4, 0));
-  __ cmp(r3, ip);
-  __ b(eq, if_false);
-  __ add(r4, r4, Operand(DescriptorArray::kDescriptorSize * kPointerSize));
-  __ bind(&entry);
-  __ cmp(r4, Operand(r2));
-  __ b(ne, &loop);
+  Register valueof_string = x1;
+  int descriptor_size = DescriptorArray::kDescriptorSize * kPointerSize;
+  __ Mov(valueof_string, Operand(isolate()->factory()->value_of_string()));
+  __ Bind(&loop);
+  __ Ldr(x15, MemOperand(descriptors, descriptor_size, PostIndex));
+  __ Cmp(x15, valueof_string);
+  __ B(eq, if_false);
+  __ Cmp(descriptors, descriptors_end);
+  __ B(ne, &loop);
 
-  __ bind(&done);
+  __ Bind(&done);
 
   // Set the bit in the map to indicate that there is no local valueOf field.
-  __ ldrb(r2, FieldMemOperand(r1, Map::kBitField2Offset));
-  __ orr(r2, r2, Operand(1 << Map::kStringWrapperSafeForDefaultValueOf));
-  __ strb(r2, FieldMemOperand(r1, Map::kBitField2Offset));
+  __ Ldrb(x2, FieldMemOperand(map, Map::kBitField2Offset));
+  __ Orr(x2, x2, 1 << Map::kStringWrapperSafeForDefaultValueOf);
+  __ Strb(x2, FieldMemOperand(map, Map::kBitField2Offset));
 
-  __ bind(&skip_lookup);
+  __ Bind(&skip_lookup);
 
-  // If a valueOf property is not found on the object check that its
-  // prototype is the un-modified String prototype. If not result is false.
-  __ ldr(r2, FieldMemOperand(r1, Map::kPrototypeOffset));
-  __ JumpIfSmi(r2, if_false);
-  __ ldr(r2, FieldMemOperand(r2, HeapObject::kMapOffset));
-  __ ldr(r3, ContextOperand(cp, Context::GLOBAL_OBJECT_INDEX));
-  __ ldr(r3, FieldMemOperand(r3, GlobalObject::kNativeContextOffset));
-  __ ldr(r3, ContextOperand(r3, Context::STRING_FUNCTION_PROTOTYPE_MAP_INDEX));
-  __ cmp(r2, r3);
+  // If a valueOf property is not found on the object check that its prototype
+  // is the unmodified String prototype. If not result is false.
+  Register prototype = x1;
+  Register global_idx = x2;
+  Register native_context = x2;
+  Register string_proto = x3;
+  Register proto_map = x4;
+  __ Ldr(prototype, FieldMemOperand(map, Map::kPrototypeOffset));
+  __ JumpIfSmi(prototype, if_false);
+  __ Ldr(proto_map, FieldMemOperand(prototype, HeapObject::kMapOffset));
+  __ Ldr(global_idx, GlobalObjectMemOperand());
+  __ Ldr(native_context,
+         FieldMemOperand(global_idx, GlobalObject::kNativeContextOffset));
+  __ Ldr(string_proto,
+         ContextMemOperand(native_context,
+                           Context::STRING_FUNCTION_PROTOTYPE_MAP_INDEX));
+  __ Cmp(proto_map, string_proto);
+
   PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
   Split(eq, if_true, if_false, fall_through);
 
   context()->Plug(if_true, if_false);
 }
 
 
 void FullCodeGenerator::EmitIsFunction(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT(args->length() == 1);
 
   VisitForAccumulatorValue(args->at(0));
 
   Label materialize_true, materialize_false;
   Label* if_true = NULL;
   Label* if_false = NULL;
   Label* fall_through = NULL;
   context()->PrepareTest(&materialize_true, &materialize_false,
                          &if_true, &if_false, &fall_through);
 
-  __ JumpIfSmi(r0, if_false);
-  __ CompareObjectType(r0, r1, r2, JS_FUNCTION_TYPE);
+  __ JumpIfSmi(x0, if_false);
+  __ CompareObjectType(x0, x10, x11, JS_FUNCTION_TYPE);
   PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
   Split(eq, if_true, if_false, fall_through);
 
   context()->Plug(if_true, if_false);
 }
 
 
 void FullCodeGenerator::EmitIsMinusZero(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT(args->length() == 1);
 
   VisitForAccumulatorValue(args->at(0));
 
   Label materialize_true, materialize_false;
   Label* if_true = NULL;
   Label* if_false = NULL;
   Label* fall_through = NULL;
   context()->PrepareTest(&materialize_true, &materialize_false,
                          &if_true, &if_false, &fall_through);
 
-  __ CheckMap(r0, r1, Heap::kHeapNumberMapRootIndex, if_false, DO_SMI_CHECK);
-  __ ldr(r2, FieldMemOperand(r0, HeapNumber::kExponentOffset));
-  __ ldr(r1, FieldMemOperand(r0, HeapNumber::kMantissaOffset));
-  __ cmp(r2, Operand(0x80000000));
-  __ cmp(r1, Operand(0x00000000), eq);
+  // Only a HeapNumber can be -0.0, so return false if we have something else.
+  __ CheckMap(x0, x1, Heap::kHeapNumberMapRootIndex, if_false, DO_SMI_CHECK);
+
+  // Test the bit pattern.
+  __ Ldr(x10, FieldMemOperand(x0, HeapNumber::kValueOffset));
+  __ Cmp(x10, 1);   // Set V on 0x8000000000000000.
 
   PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
-  Split(eq, if_true, if_false, fall_through);
+  Split(vs, if_true, if_false, fall_through);
 
   context()->Plug(if_true, if_false);
 }
 
 
 void FullCodeGenerator::EmitIsArray(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT(args->length() == 1);
 
   VisitForAccumulatorValue(args->at(0));
 
   Label materialize_true, materialize_false;
   Label* if_true = NULL;
   Label* if_false = NULL;
   Label* fall_through = NULL;
   context()->PrepareTest(&materialize_true, &materialize_false,
                          &if_true, &if_false, &fall_through);
 
-  __ JumpIfSmi(r0, if_false);
-  __ CompareObjectType(r0, r1, r1, JS_ARRAY_TYPE);
+  __ JumpIfSmi(x0, if_false);
+  __ CompareObjectType(x0, x10, x11, JS_ARRAY_TYPE);
   PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
   Split(eq, if_true, if_false, fall_through);
 
   context()->Plug(if_true, if_false);
 }
 
 
 void FullCodeGenerator::EmitIsRegExp(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT(args->length() == 1);
 
   VisitForAccumulatorValue(args->at(0));
 
   Label materialize_true, materialize_false;
   Label* if_true = NULL;
   Label* if_false = NULL;
   Label* fall_through = NULL;
   context()->PrepareTest(&materialize_true, &materialize_false,
                          &if_true, &if_false, &fall_through);
 
-  __ JumpIfSmi(r0, if_false);
-  __ CompareObjectType(r0, r1, r1, JS_REGEXP_TYPE);
+  __ JumpIfSmi(x0, if_false);
+  __ CompareObjectType(x0, x10, x11, JS_REGEXP_TYPE);
   PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
   Split(eq, if_true, if_false, fall_through);
 
   context()->Plug(if_true, if_false);
 }
 
 
 
 void FullCodeGenerator::EmitIsConstructCall(CallRuntime* expr) {
   ASSERT(expr->arguments()->length() == 0);
 
   Label materialize_true, materialize_false;
   Label* if_true = NULL;
   Label* if_false = NULL;
   Label* fall_through = NULL;
   context()->PrepareTest(&materialize_true, &materialize_false,
                          &if_true, &if_false, &fall_through);
 
   // Get the frame pointer for the calling frame.
-  __ ldr(r2, MemOperand(fp, StandardFrameConstants::kCallerFPOffset));
+  __ Ldr(x2, MemOperand(fp, StandardFrameConstants::kCallerFPOffset));
 
   // Skip the arguments adaptor frame if it exists.
-  __ ldr(r1, MemOperand(r2, StandardFrameConstants::kContextOffset));
-  __ cmp(r1, Operand(Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR)));
-  __ ldr(r2, MemOperand(r2, StandardFrameConstants::kCallerFPOffset), eq);
+  Label check_frame_marker;
+  __ Ldr(x1, MemOperand(x2, StandardFrameConstants::kContextOffset));
+  __ Cmp(x1, Operand(Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR)));
+  __ B(ne, &check_frame_marker);
+  __ Ldr(x2, MemOperand(x2, StandardFrameConstants::kCallerFPOffset));
 
   // Check the marker in the calling frame.
-  __ ldr(r1, MemOperand(r2, StandardFrameConstants::kMarkerOffset));
-  __ cmp(r1, Operand(Smi::FromInt(StackFrame::CONSTRUCT)));
+  __ Bind(&check_frame_marker);
+  __ Ldr(x1, MemOperand(x2, StandardFrameConstants::kMarkerOffset));
+  __ Cmp(x1, Operand(Smi::FromInt(StackFrame::CONSTRUCT)));
   PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
   Split(eq, if_true, if_false, fall_through);
 
   context()->Plug(if_true, if_false);
 }
 
 
 void FullCodeGenerator::EmitObjectEquals(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT(args->length() == 2);
 
   // Load the two objects into registers and perform the comparison.
   VisitForStackValue(args->at(0));
   VisitForAccumulatorValue(args->at(1));
 
   Label materialize_true, materialize_false;
   Label* if_true = NULL;
   Label* if_false = NULL;
   Label* fall_through = NULL;
   context()->PrepareTest(&materialize_true, &materialize_false,
                          &if_true, &if_false, &fall_through);
 
-  __ pop(r1);
-  __ cmp(r0, r1);
+  __ Pop(x1);
+  __ Cmp(x0, x1);
   PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
   Split(eq, if_true, if_false, fall_through);
 
   context()->Plug(if_true, if_false);
 }
 
 
 void FullCodeGenerator::EmitArguments(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT(args->length() == 1);
 
-  // ArgumentsAccessStub expects the key in edx and the formal
-  // parameter count in r0.
+  // ArgumentsAccessStub expects the key in x1.
   VisitForAccumulatorValue(args->at(0));
-  __ mov(r1, r0);
-  __ mov(r0, Operand(Smi::FromInt(info_->scope()->num_parameters())));
+  __ Mov(x1, x0);
+  __ Mov(x0, Operand(Smi::FromInt(info_->scope()->num_parameters())));
   ArgumentsAccessStub stub(ArgumentsAccessStub::READ_ELEMENT);
   __ CallStub(&stub);
-  context()->Plug(r0);
+  context()->Plug(x0);
 }
 
 
 void FullCodeGenerator::EmitArgumentsLength(CallRuntime* expr) {
   ASSERT(expr->arguments()->length() == 0);
-
+  Label exit;
   // Get the number of formal parameters.
-  __ mov(r0, Operand(Smi::FromInt(info_->scope()->num_parameters())));
+  __ Mov(x0, Operand(Smi::FromInt(info_->scope()->num_parameters())));
 
   // Check if the calling frame is an arguments adaptor frame.
-  __ ldr(r2, MemOperand(fp, StandardFrameConstants::kCallerFPOffset));
-  __ ldr(r3, MemOperand(r2, StandardFrameConstants::kContextOffset));
-  __ cmp(r3, Operand(Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR)));
+  __ Ldr(x12, MemOperand(fp, StandardFrameConstants::kCallerFPOffset));
+  __ Ldr(x13, MemOperand(x12, StandardFrameConstants::kContextOffset));
+  __ Cmp(x13, Operand(Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR)));
+  __ B(ne, &exit);
 
   // Arguments adaptor case: Read the arguments length from the
   // adaptor frame.
-  __ ldr(r0, MemOperand(r2, ArgumentsAdaptorFrameConstants::kLengthOffset), eq);
+  __ Ldr(x0, MemOperand(x12, ArgumentsAdaptorFrameConstants::kLengthOffset));
 
-  context()->Plug(r0);
+  __ Bind(&exit);
+  context()->Plug(x0);
 }
 
 
 void FullCodeGenerator::EmitClassOf(CallRuntime* expr) {
+  ASM_LOCATION("FullCodeGenerator::EmitClassOf");
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT(args->length() == 1);
   Label done, null, function, non_function_constructor;
 
   VisitForAccumulatorValue(args->at(0));
 
   // If the object is a smi, we return null.
-  __ JumpIfSmi(r0, &null);
+  __ JumpIfSmi(x0, &null);
 
   // Check that the object is a JS object but take special care of JS
   // functions to make sure they have 'Function' as their class.
   // Assume that there are only two callable types, and one of them is at
   // either end of the type range for JS object types. Saves extra comparisons.
   STATIC_ASSERT(NUM_OF_CALLABLE_SPEC_OBJECT_TYPES == 2);
-  __ CompareObjectType(r0, r0, r1, FIRST_SPEC_OBJECT_TYPE);
-  // Map is now in r0.
-  __ b(lt, &null);
+  __ CompareObjectType(x0, x10, x11, FIRST_SPEC_OBJECT_TYPE);
+  // x10: object's map.
+  // x11: object's type.
+  __ B(lt, &null);
   STATIC_ASSERT(FIRST_NONCALLABLE_SPEC_OBJECT_TYPE ==
                 FIRST_SPEC_OBJECT_TYPE + 1);
-  __ b(eq, &function);
+  __ B(eq, &function);
 
-  __ cmp(r1, Operand(LAST_SPEC_OBJECT_TYPE));
+  __ Cmp(x11, LAST_SPEC_OBJECT_TYPE);
   STATIC_ASSERT(LAST_NONCALLABLE_SPEC_OBJECT_TYPE ==
                 LAST_SPEC_OBJECT_TYPE - 1);
-  __ b(eq, &function);
+  __ B(eq, &function);
   // Assume that there is no larger type.
   STATIC_ASSERT(LAST_NONCALLABLE_SPEC_OBJECT_TYPE == LAST_TYPE - 1);
 
   // Check if the constructor in the map is a JS function.
-  __ ldr(r0, FieldMemOperand(r0, Map::kConstructorOffset));
-  __ CompareObjectType(r0, r1, r1, JS_FUNCTION_TYPE);
-  __ b(ne, &non_function_constructor);
+  __ Ldr(x12, FieldMemOperand(x10, Map::kConstructorOffset));
+  __ JumpIfNotObjectType(x12, x13, x14, JS_FUNCTION_TYPE,
+                         &non_function_constructor);
 
-  // r0 now contains the constructor function. Grab the
+  // x12 now contains the constructor function. Grab the
   // instance class name from there.
-  __ ldr(r0, FieldMemOperand(r0, JSFunction::kSharedFunctionInfoOffset));
-  __ ldr(r0, FieldMemOperand(r0, SharedFunctionInfo::kInstanceClassNameOffset));
-  __ b(&done);
+  __ Ldr(x13, FieldMemOperand(x12, JSFunction::kSharedFunctionInfoOffset));
+  __ Ldr(x0,
+         FieldMemOperand(x13, SharedFunctionInfo::kInstanceClassNameOffset));
+  __ B(&done);
 
   // Functions have class 'Function'.
-  __ bind(&function);
-  __ LoadRoot(r0, Heap::kfunction_class_stringRootIndex);
-  __ jmp(&done);
+  __ Bind(&function);
+  __ LoadRoot(x0, Heap::kfunction_class_stringRootIndex);
+  __ B(&done);
 
   // Objects with a non-function constructor have class 'Object'.
-  __ bind(&non_function_constructor);
-  __ LoadRoot(r0, Heap::kObject_stringRootIndex);
-  __ jmp(&done);
+  __ Bind(&non_function_constructor);
+  __ LoadRoot(x0, Heap::kObject_stringRootIndex);
+  __ B(&done);
 
   // Non-JS objects have class null.
-  __ bind(&null);
-  __ LoadRoot(r0, Heap::kNullValueRootIndex);
+  __ Bind(&null);
+  __ LoadRoot(x0, Heap::kNullValueRootIndex);
 
   // All done.
-  __ bind(&done);
+  __ Bind(&done);
 
-  context()->Plug(r0);
+  context()->Plug(x0);
 }
 
 
 void FullCodeGenerator::EmitLog(CallRuntime* expr) {
   // Conditionally generate a log call.
   // Args:
   //   0 (literal string): The type of logging (corresponds to the flags).
   //     This is used to determine whether or not to generate the log call.
   //   1 (string): Format string.  Access the string at argument index 2
   //     with '%2s' (see Logger::LogRuntime for all the formats).
   //   2 (array): Arguments to the format string.
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT_EQ(args->length(), 3);
   if (CodeGenerator::ShouldGenerateLog(isolate(), args->at(0))) {
     VisitForStackValue(args->at(1));
     VisitForStackValue(args->at(2));
     __ CallRuntime(Runtime::kLog, 2);
   }
 
   // Finally, we're expected to leave a value on the top of the stack.
-  __ LoadRoot(r0, Heap::kUndefinedValueRootIndex);
-  context()->Plug(r0);
+  __ LoadRoot(x0, Heap::kUndefinedValueRootIndex);
+  context()->Plug(x0);
 }
 
 
 void FullCodeGenerator::EmitSubString(CallRuntime* expr) {
   // Load the arguments on the stack and call the stub.
   SubStringStub stub;
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT(args->length() == 3);
   VisitForStackValue(args->at(0));
   VisitForStackValue(args->at(1));
   VisitForStackValue(args->at(2));
   __ CallStub(&stub);
-  context()->Plug(r0);
+  context()->Plug(x0);
 }
 
 
 void FullCodeGenerator::EmitRegExpExec(CallRuntime* expr) {
   // Load the arguments on the stack and call the stub.
   RegExpExecStub stub;
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT(args->length() == 4);
   VisitForStackValue(args->at(0));
   VisitForStackValue(args->at(1));
   VisitForStackValue(args->at(2));
   VisitForStackValue(args->at(3));
   __ CallStub(&stub);
-  context()->Plug(r0);
+  context()->Plug(x0);
 }
 
 
 void FullCodeGenerator::EmitValueOf(CallRuntime* expr) {
+  ASM_LOCATION("FullCodeGenerator::EmitValueOf");
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT(args->length() == 1);
   VisitForAccumulatorValue(args->at(0));  // Load the object.
 
   Label done;
   // If the object is a smi return the object.
-  __ JumpIfSmi(r0, &done);
+  __ JumpIfSmi(x0, &done);
   // If the object is not a value type, return the object.
-  __ CompareObjectType(r0, r1, r1, JS_VALUE_TYPE);
-  __ ldr(r0, FieldMemOperand(r0, JSValue::kValueOffset), eq);
+  __ JumpIfNotObjectType(x0, x10, x11, JS_VALUE_TYPE, &done);
+  __ Ldr(x0, FieldMemOperand(x0, JSValue::kValueOffset));
 
-  __ bind(&done);
-  context()->Plug(r0);
+  __ Bind(&done);
+  context()->Plug(x0);
 }
 
 
 void FullCodeGenerator::EmitDateField(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT(args->length() == 2);
   ASSERT_NE(NULL, args->at(1)->AsLiteral());
   Smi* index = Smi::cast(*(args->at(1)->AsLiteral()->value()));
 
   VisitForAccumulatorValue(args->at(0));  // Load the object.
 
   Label runtime, done, not_date_object;
-  Register object = r0;
-  Register result = r0;
-  Register scratch0 = r9;
-  Register scratch1 = r1;
+  Register object = x0;
+  Register result = x0;
+  Register stamp_addr = x10;
+  Register stamp_cache = x11;
 
   __ JumpIfSmi(object, &not_date_object);
-  __ CompareObjectType(object, scratch1, scratch1, JS_DATE_TYPE);
-  __ b(ne, &not_date_object);
+  __ JumpIfNotObjectType(object, x10, x10, JS_DATE_TYPE, &not_date_object);
 
   if (index->value() == 0) {
-    __ ldr(result, FieldMemOperand(object, JSDate::kValueOffset));
-    __ jmp(&done);
+    __ Ldr(result, FieldMemOperand(object, JSDate::kValueOffset));
+    __ B(&done);
   } else {
     if (index->value() < JSDate::kFirstUncachedField) {
       ExternalReference stamp = ExternalReference::date_cache_stamp(isolate());
-      __ mov(scratch1, Operand(stamp));
-      __ ldr(scratch1, MemOperand(scratch1));
-      __ ldr(scratch0, FieldMemOperand(object, JSDate::kCacheStampOffset));
-      __ cmp(scratch1, scratch0);
-      __ b(ne, &runtime);
-      __ ldr(result, FieldMemOperand(object, JSDate::kValueOffset +
+      __ Mov(x10, Operand(stamp));
+      __ Ldr(stamp_addr, MemOperand(x10));
+      __ Ldr(stamp_cache, FieldMemOperand(object, JSDate::kCacheStampOffset));
+      __ Cmp(stamp_addr, stamp_cache);
+      __ B(ne, &runtime);
+      __ Ldr(result, FieldMemOperand(object, JSDate::kValueOffset +
                                              kPointerSize * index->value()));
-      __ jmp(&done);
+      __ B(&done);
     }
-    __ bind(&runtime);
-    __ PrepareCallCFunction(2, scratch1);
-    __ mov(r1, Operand(index));
+
+    __ Bind(&runtime);
+    __ Mov(x1, Operand(index));
     __ CallCFunction(ExternalReference::get_date_field_function(isolate()), 2);
-    __ jmp(&done);
+    __ B(&done);
   }
 
-  __ bind(&not_date_object);
+  __ Bind(&not_date_object);
   __ CallRuntime(Runtime::kThrowNotDateError, 0);
-  __ bind(&done);
-  context()->Plug(r0);
+  __ Bind(&done);
+  context()->Plug(x0);
 }
 
 
 void FullCodeGenerator::EmitOneByteSeqStringSetChar(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT_EQ(3, args->length());
 
-  Register string = r0;
-  Register index = r1;
-  Register value = r2;
+  Register string = x0;
+  Register index = x1;
+  Register value = x2;
+  Register scratch = x10;
 
   VisitForStackValue(args->at(1));  // index
   VisitForStackValue(args->at(2));  // value
   VisitForAccumulatorValue(args->at(0));  // string
-  __ Pop(index, value);
+  __ Pop(value, index);
 
   if (FLAG_debug_code) {
-    __ SmiTst(value);
-    __ ThrowIf(ne, kNonSmiValue);
-    __ SmiTst(index);
-    __ ThrowIf(ne, kNonSmiIndex);
-    __ SmiUntag(index, index);
+    __ AssertSmi(value, kNonSmiValue);
+    __ AssertSmi(index, kNonSmiIndex);
     static const uint32_t one_byte_seq_type = kSeqStringTag | kOneByteStringTag;
-    __ EmitSeqStringSetCharCheck(string, index, value, one_byte_seq_type);
-    __ SmiTag(index, index);
+    __ EmitSeqStringSetCharCheck(string, index, kIndexIsSmi, scratch,
+                                 one_byte_seq_type);
   }
 
-  __ SmiUntag(value, value);
-  __ add(ip,
-         string,
-         Operand(SeqOneByteString::kHeaderSize - kHeapObjectTag));
-  __ strb(value, MemOperand(ip, index, LSR, kSmiTagSize));
+  __ Add(scratch, string, SeqOneByteString::kHeaderSize - kHeapObjectTag);
+  __ SmiUntag(value);
+  __ SmiUntag(index);
+  __ Strb(value, MemOperand(scratch, index));
   context()->Plug(string);
 }
 
 
 void FullCodeGenerator::EmitTwoByteSeqStringSetChar(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT_EQ(3, args->length());
 
-  Register string = r0;
-  Register index = r1;
-  Register value = r2;
+  Register string = x0;
+  Register index = x1;
+  Register value = x2;
+  Register scratch = x10;
 
   VisitForStackValue(args->at(1));  // index
   VisitForStackValue(args->at(2));  // value
   VisitForAccumulatorValue(args->at(0));  // string
-  __ Pop(index, value);
+  __ Pop(value, index);
 
   if (FLAG_debug_code) {
-    __ SmiTst(value);
-    __ ThrowIf(ne, kNonSmiValue);
-    __ SmiTst(index);
-    __ ThrowIf(ne, kNonSmiIndex);
-    __ SmiUntag(index, index);
+    __ AssertSmi(value, kNonSmiValue);
+    __ AssertSmi(index, kNonSmiIndex);
     static const uint32_t two_byte_seq_type = kSeqStringTag | kTwoByteStringTag;
-    __ EmitSeqStringSetCharCheck(string, index, value, two_byte_seq_type);
-    __ SmiTag(index, index);
+    __ EmitSeqStringSetCharCheck(string, index, kIndexIsSmi, scratch,
+                                 two_byte_seq_type);
   }
 
-  __ SmiUntag(value, value);
-  __ add(ip,
-         string,
-         Operand(SeqTwoByteString::kHeaderSize - kHeapObjectTag));
-  STATIC_ASSERT(kSmiTagSize == 1 && kSmiTag == 0);
-  __ strh(value, MemOperand(ip, index));
+  __ Add(scratch, string, SeqTwoByteString::kHeaderSize - kHeapObjectTag);
+  __ SmiUntag(value);
+  __ SmiUntag(index);
+  __ Strh(value, MemOperand(scratch, index, LSL, 1));
   context()->Plug(string);
 }
 
 
-
 void FullCodeGenerator::EmitMathPow(CallRuntime* expr) {
-  // Load the arguments on the stack and call the runtime function.
+  // Load the arguments on the stack and call the MathPow stub.
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT(args->length() == 2);
   VisitForStackValue(args->at(0));
   VisitForStackValue(args->at(1));
   MathPowStub stub(MathPowStub::ON_STACK);
   __ CallStub(&stub);
-  context()->Plug(r0);
+  context()->Plug(x0);
 }
 
 
 void FullCodeGenerator::EmitSetValueOf(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT(args->length() == 2);
   VisitForStackValue(args->at(0));  // Load the object.
   VisitForAccumulatorValue(args->at(1));  // Load the value.
-  __ pop(r1);  // r0 = value. r1 = object.
+  __ Pop(x1);
+  // x0 = value.
+  // x1 = object.
 
   Label done;
   // If the object is a smi, return the value.
-  __ JumpIfSmi(r1, &done);
+  __ JumpIfSmi(x1, &done);
 
   // If the object is not a value type, return the value.
-  __ CompareObjectType(r1, r2, r2, JS_VALUE_TYPE);
-  __ b(ne, &done);
+  __ JumpIfNotObjectType(x1, x10, x11, JS_VALUE_TYPE, &done);
 
   // Store the value.
-  __ str(r0, FieldMemOperand(r1, JSValue::kValueOffset));
-  // Update the write barrier.  Save the value as it will be
+  __ Str(x0, FieldMemOperand(x1, JSValue::kValueOffset));
+  // Update the write barrier. Save the value as it will be
   // overwritten by the write barrier code and is needed afterward.
-  __ mov(r2, r0);
+  __ Mov(x10, x0);
   __ RecordWriteField(
-      r1, JSValue::kValueOffset, r2, r3, kLRHasBeenSaved, kDontSaveFPRegs);
+      x1, JSValue::kValueOffset, x10, x11, kLRHasBeenSaved, kDontSaveFPRegs);
 
-  __ bind(&done);
-  context()->Plug(r0);
+  __ Bind(&done);
+  context()->Plug(x0);
 }
 
 
 void FullCodeGenerator::EmitNumberToString(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT_EQ(args->length(), 1);
-  // Load the argument into r0 and call the stub.
+
+  // Load the argument into x0 and call the stub.
   VisitForAccumulatorValue(args->at(0));
 
   NumberToStringStub stub;
   __ CallStub(&stub);
-  context()->Plug(r0);
+  context()->Plug(x0);
 }
 
 
 void FullCodeGenerator::EmitStringCharFromCode(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT(args->length() == 1);
+
   VisitForAccumulatorValue(args->at(0));
 
   Label done;
-  StringCharFromCodeGenerator generator(r0, r1);
+  Register code = x0;
+  Register result = x1;
+
+  StringCharFromCodeGenerator generator(code, result);
   generator.GenerateFast(masm_);
-  __ jmp(&done);
+  __ B(&done);
 
   NopRuntimeCallHelper call_helper;
   generator.GenerateSlow(masm_, call_helper);
 
-  __ bind(&done);
-  context()->Plug(r1);
+  __ Bind(&done);
+  context()->Plug(result);
 }
 
 
 void FullCodeGenerator::EmitStringCharCodeAt(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT(args->length() == 2);
+
   VisitForStackValue(args->at(0));
   VisitForAccumulatorValue(args->at(1));
 
-  Register object = r1;
-  Register index = r0;
-  Register result = r3;
+  Register object = x1;
+  Register index = x0;
+  Register result = x3;
 
-  __ pop(object);
+  __ Pop(object);
 
   Label need_conversion;
   Label index_out_of_range;
   Label done;
   StringCharCodeAtGenerator generator(object,
                                       index,
                                       result,
                                       &need_conversion,
                                       &need_conversion,
                                       &index_out_of_range,
                                       STRING_INDEX_IS_NUMBER);
   generator.GenerateFast(masm_);
-  __ jmp(&done);
+  __ B(&done);
 
-  __ bind(&index_out_of_range);
-  // When the index is out of range, the spec requires us to return
-  // NaN.
+  __ Bind(&index_out_of_range);
+  // When the index is out of range, the spec requires us to return NaN.
   __ LoadRoot(result, Heap::kNanValueRootIndex);
-  __ jmp(&done);
+  __ B(&done);
 
-  __ bind(&need_conversion);
+  __ Bind(&need_conversion);
   // Load the undefined value into the result register, which will
   // trigger conversion.
   __ LoadRoot(result, Heap::kUndefinedValueRootIndex);
-  __ jmp(&done);
+  __ B(&done);
 
   NopRuntimeCallHelper call_helper;
   generator.GenerateSlow(masm_, call_helper);
 
-  __ bind(&done);
+  __ Bind(&done);
   context()->Plug(result);
 }
 
 
 void FullCodeGenerator::EmitStringCharAt(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT(args->length() == 2);
+
   VisitForStackValue(args->at(0));
   VisitForAccumulatorValue(args->at(1));
 
-  Register object = r1;
-  Register index = r0;
-  Register scratch = r3;
-  Register result = r0;
+  Register object = x1;
+  Register index = x0;
+  Register result = x0;
 
-  __ pop(object);
+  __ Pop(object);
 
   Label need_conversion;
   Label index_out_of_range;
   Label done;
   StringCharAtGenerator generator(object,
                                   index,
-                                  scratch,
+                                  x3,
                                   result,
                                   &need_conversion,
                                   &need_conversion,
                                   &index_out_of_range,
                                   STRING_INDEX_IS_NUMBER);
   generator.GenerateFast(masm_);
-  __ jmp(&done);
+  __ B(&done);
 
-  __ bind(&index_out_of_range);
+  __ Bind(&index_out_of_range);
   // When the index is out of range, the spec requires us to return
   // the empty string.
   __ LoadRoot(result, Heap::kempty_stringRootIndex);
-  __ jmp(&done);
+  __ B(&done);
 
-  __ bind(&need_conversion);
-  // Move smi zero into the result register, which will trigger
-  // conversion.
-  __ mov(result, Operand(Smi::FromInt(0)));
-  __ jmp(&done);
+  __ Bind(&need_conversion);
+  // Move smi zero into the result register, which will trigger conversion.
+  __ Mov(result, Operand(Smi::FromInt(0)));
+  __ B(&done);
 
   NopRuntimeCallHelper call_helper;
   generator.GenerateSlow(masm_, call_helper);
 
-  __ bind(&done);
+  __ Bind(&done);
   context()->Plug(result);
 }
 
 
 void FullCodeGenerator::EmitStringAdd(CallRuntime* expr) {
+  ASM_LOCATION("FullCodeGenerator::EmitStringAdd");
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT_EQ(2, args->length());
 
-  if (FLAG_new_string_add) {
-    VisitForStackValue(args->at(0));
-    VisitForAccumulatorValue(args->at(1));
+  VisitForStackValue(args->at(0));
+  VisitForAccumulatorValue(args->at(1));
 
-    __ pop(r1);
-    NewStringAddStub stub(STRING_ADD_CHECK_BOTH, NOT_TENURED);
-    __ CallStub(&stub);
-  } else {
-    VisitForStackValue(args->at(0));
-    VisitForStackValue(args->at(1));
+  __ Pop(x1);
+  StringAddStub stub(STRING_ADD_CHECK_BOTH, NOT_TENURED);
+  __ CallStub(&stub);
 
-    StringAddStub stub(STRING_ADD_CHECK_BOTH);
-    __ CallStub(&stub);
-  }
-  context()->Plug(r0);
+  context()->Plug(x0);
 }
 
 
 void FullCodeGenerator::EmitStringCompare(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT_EQ(2, args->length());
   VisitForStackValue(args->at(0));
   VisitForStackValue(args->at(1));
 
   StringCompareStub stub;
   __ CallStub(&stub);
-  context()->Plug(r0);
+  context()->Plug(x0);
 }
 
 
 void FullCodeGenerator::EmitMathLog(CallRuntime* expr) {
   // Load the argument on the stack and call the runtime function.
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT(args->length() == 1);
   VisitForStackValue(args->at(0));
   __ CallRuntime(Runtime::kMath_log, 1);
-  context()->Plug(r0);
+  context()->Plug(x0);
 }
 
 
 void FullCodeGenerator::EmitMathSqrt(CallRuntime* expr) {
   // Load the argument on the stack and call the runtime function.
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT(args->length() == 1);
   VisitForStackValue(args->at(0));
   __ CallRuntime(Runtime::kMath_sqrt, 1);
-  context()->Plug(r0);
+  context()->Plug(x0);
 }
 
 
 void FullCodeGenerator::EmitCallFunction(CallRuntime* expr) {
+  ASM_LOCATION("FullCodeGenerator::EmitCallFunction");
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT(args->length() >= 2);
 
   int arg_count = args->length() - 2;  // 2 ~ receiver and function.
   for (int i = 0; i < arg_count + 1; i++) {
     VisitForStackValue(args->at(i));
   }
   VisitForAccumulatorValue(args->last());  // Function.
 
   Label runtime, done;
   // Check for non-function argument (including proxy).
-  __ JumpIfSmi(r0, &runtime);
-  __ CompareObjectType(r0, r1, r1, JS_FUNCTION_TYPE);
-  __ b(ne, &runtime);
+  __ JumpIfSmi(x0, &runtime);
+  __ JumpIfNotObjectType(x0, x1, x1, JS_FUNCTION_TYPE, &runtime);
 
-  // InvokeFunction requires the function in r1. Move it in there.
-  __ mov(r1, result_register());
+  // InvokeFunction requires the function in x1. Move it in there.
+  __ Mov(x1, x0);
   ParameterCount count(arg_count);
-  __ InvokeFunction(r1, count, CALL_FUNCTION, NullCallWrapper());
-  __ ldr(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
-  __ jmp(&done);
+  __ InvokeFunction(x1, count, CALL_FUNCTION, NullCallWrapper());
+  __ Ldr(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
+  __ B(&done);
 
-  __ bind(&runtime);
-  __ push(r0);
+  __ Bind(&runtime);
+  __ Push(x0);
   __ CallRuntime(Runtime::kCall, args->length());
-  __ bind(&done);
+  __ Bind(&done);
 
-  context()->Plug(r0);
+  context()->Plug(x0);
 }
 
 
 void FullCodeGenerator::EmitRegExpConstructResult(CallRuntime* expr) {
   RegExpConstructResultStub stub;
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT(args->length() == 3);
   VisitForStackValue(args->at(0));
   VisitForStackValue(args->at(1));
-  VisitForStackValue(args->at(2));
+  VisitForAccumulatorValue(args->at(2));
+  __ Pop(x1, x2);
   __ CallStub(&stub);
-  context()->Plug(r0);
+  context()->Plug(x0);
 }
 
 
 void FullCodeGenerator::EmitGetFromCache(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT_EQ(2, args->length());
   ASSERT_NE(NULL, args->at(0)->AsLiteral());
   int cache_id = Smi::cast(*(args->at(0)->AsLiteral()->value()))->value();
 
   Handle<FixedArray> jsfunction_result_caches(
       isolate()->native_context()->jsfunction_result_caches());
   if (jsfunction_result_caches->length() <= cache_id) {
     __ Abort(kAttemptToUseUndefinedCache);
-    __ LoadRoot(r0, Heap::kUndefinedValueRootIndex);
-    context()->Plug(r0);
+    __ LoadRoot(x0, Heap::kUndefinedValueRootIndex);
+    context()->Plug(x0);
     return;
   }
 
   VisitForAccumulatorValue(args->at(1));
 
-  Register key = r0;
-  Register cache = r1;
-  __ ldr(cache, ContextOperand(cp, Context::GLOBAL_OBJECT_INDEX));
-  __ ldr(cache, FieldMemOperand(cache, GlobalObject::kNativeContextOffset));
-  __ ldr(cache, ContextOperand(cache, Context::JSFUNCTION_RESULT_CACHES_INDEX));
-  __ ldr(cache,
+  Register key = x0;
+  Register cache = x1;
+  __ Ldr(cache, GlobalObjectMemOperand());
+  __ Ldr(cache, FieldMemOperand(cache, GlobalObject::kNativeContextOffset));
+  __ Ldr(cache, ContextMemOperand(cache,
+                                  Context::JSFUNCTION_RESULT_CACHES_INDEX));
+  __ Ldr(cache,
          FieldMemOperand(cache, FixedArray::OffsetOfElementAt(cache_id)));
 
+  Label done;
+  __ Ldrsw(x2, UntagSmiFieldMemOperand(cache,
+                                       JSFunctionResultCache::kFingerOffset));
+  __ Add(x3, cache, FixedArray::kHeaderSize - kHeapObjectTag);
+  __ Add(x3, x3, Operand(x2, LSL, kPointerSizeLog2));
 
-  Label done, not_found;
-  // tmp now holds finger offset as a smi.
-  __ ldr(r2, FieldMemOperand(cache, JSFunctionResultCache::kFingerOffset));
-  // r2 now holds finger offset as a smi.
-  __ add(r3, cache, Operand(FixedArray::kHeaderSize - kHeapObjectTag));
-  // r3 now points to the start of fixed array elements.
-  __ ldr(r2, MemOperand::PointerAddressFromSmiKey(r3, r2, PreIndex));
-  // Note side effect of PreIndex: r3 now points to the key of the pair.
-  __ cmp(key, r2);
-  __ b(ne, &not_found);
+  // Load the key and data from the cache.
+  __ Ldp(x2, x3, MemOperand(x3));
 
-  __ ldr(r0, MemOperand(r3, kPointerSize));
-  __ b(&done);
+  __ Cmp(key, x2);
+  __ CmovX(x0, x3, eq);
+  __ B(eq, &done);
 
-  __ bind(&not_found);
   // Call runtime to perform the lookup.
   __ Push(cache, key);
   __ CallRuntime(Runtime::kGetFromCache, 2);
 
-  __ bind(&done);
-  context()->Plug(r0);
+  __ Bind(&done);
+  context()->Plug(x0);
 }
 
 
-void FullCodeGenerator::EmitIsRegExpEquivalent(CallRuntime* expr) {
-  ZoneList<Expression*>* args = expr->arguments();
-  ASSERT_EQ(2, args->length());
-
-  Register right = r0;
-  Register left = r1;
-  Register tmp = r2;
-  Register tmp2 = r3;
-
-  VisitForStackValue(args->at(0));
-  VisitForAccumulatorValue(args->at(1));
-  __ pop(left);
-
-  Label done, fail, ok;
-  __ cmp(left, Operand(right));
-  __ b(eq, &ok);
-  // Fail if either is a non-HeapObject.
-  __ and_(tmp, left, Operand(right));
-  __ JumpIfSmi(tmp, &fail);
-  __ ldr(tmp, FieldMemOperand(left, HeapObject::kMapOffset));
-  __ ldrb(tmp2, FieldMemOperand(tmp, Map::kInstanceTypeOffset));
-  __ cmp(tmp2, Operand(JS_REGEXP_TYPE));
-  __ b(ne, &fail);
-  __ ldr(tmp2, FieldMemOperand(right, HeapObject::kMapOffset));
-  __ cmp(tmp, Operand(tmp2));
-  __ b(ne, &fail);
-  __ ldr(tmp, FieldMemOperand(left, JSRegExp::kDataOffset));
-  __ ldr(tmp2, FieldMemOperand(right, JSRegExp::kDataOffset));
-  __ cmp(tmp, tmp2);
-  __ b(eq, &ok);
-  __ bind(&fail);
-  __ LoadRoot(r0, Heap::kFalseValueRootIndex);
-  __ jmp(&done);
-  __ bind(&ok);
-  __ LoadRoot(r0, Heap::kTrueValueRootIndex);
-  __ bind(&done);
-
-  context()->Plug(r0);
-}
-
-
 void FullCodeGenerator::EmitHasCachedArrayIndex(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   VisitForAccumulatorValue(args->at(0));
 
   Label materialize_true, materialize_false;
   Label* if_true = NULL;
   Label* if_false = NULL;
   Label* fall_through = NULL;
   context()->PrepareTest(&materialize_true, &materialize_false,
                          &if_true, &if_false, &fall_through);
 
-  __ ldr(r0, FieldMemOperand(r0, String::kHashFieldOffset));
-  __ tst(r0, Operand(String::kContainsCachedArrayIndexMask));
+  __ Ldr(x10, FieldMemOperand(x0, String::kHashFieldOffset));
+  __ Tst(x10, String::kContainsCachedArrayIndexMask);
   PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
   Split(eq, if_true, if_false, fall_through);
 
   context()->Plug(if_true, if_false);
 }
 
 
 void FullCodeGenerator::EmitGetCachedArrayIndex(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT(args->length() == 1);
   VisitForAccumulatorValue(args->at(0));
 
-  __ AssertString(r0);
+  __ AssertString(x0);
 
-  __ ldr(r0, FieldMemOperand(r0, String::kHashFieldOffset));
-  __ IndexFromHash(r0, r0);
+  __ Ldr(x10, FieldMemOperand(x0, String::kHashFieldOffset));
+  __ IndexFromHash(x10, x0);
 
-  context()->Plug(r0);
+  context()->Plug(x0);
 }
 
 
 void FullCodeGenerator::EmitFastAsciiArrayJoin(CallRuntime* expr) {
-  Label bailout, done, one_char_separator, long_separator, non_trivial_array,
-      not_size_one_array, loop, empty_separator_loop, one_char_separator_loop,
-      one_char_separator_loop_entry, long_separator_loop;
+  ASM_LOCATION("FullCodeGenerator::EmitFastAsciiArrayJoin");
+
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT(args->length() == 2);
   VisitForStackValue(args->at(1));
   VisitForAccumulatorValue(args->at(0));
 
-  // All aliases of the same register have disjoint lifetimes.
-  Register array = r0;
-  Register elements = no_reg;  // Will be r0.
-  Register result = no_reg;  // Will be r0.
-  Register separator = r1;
-  Register array_length = r2;
-  Register result_pos = no_reg;  // Will be r2
-  Register string_length = r3;
-  Register string = r4;
-  Register element = r5;
-  Register elements_end = r6;
-  Register scratch = r9;
+  Register array = x0;
+  Register result = x0;
+  Register elements = x1;
+  Register element = x2;
+  Register separator = x3;
+  Register array_length = x4;
+  Register result_pos = x5;
+  Register map = x6;
+  Register string_length = x10;
+  Register elements_end = x11;
+  Register string = x12;
+  Register scratch1 = x13;
+  Register scratch2 = x14;
+  Register scratch3 = x7;
+  Register separator_length = x15;
 
-  // Separator operand is on the stack.
-  __ pop(separator);
+  Label bailout, done, one_char_separator, long_separator,
+      non_trivial_array, not_size_one_array, loop,
+      empty_separator_loop, one_char_separator_loop,
+      one_char_separator_loop_entry, long_separator_loop;
+
+  // The separator operand is on the stack.
+  __ Pop(separator);
 
   // Check that the array is a JSArray.
   __ JumpIfSmi(array, &bailout);
-  __ CompareObjectType(array, scratch, array_length, JS_ARRAY_TYPE);
-  __ b(ne, &bailout);
+  __ JumpIfNotObjectType(array, map, scratch1, JS_ARRAY_TYPE, &bailout);
 
   // Check that the array has fast elements.
-  __ CheckFastElements(scratch, array_length, &bailout);
+  __ CheckFastElements(map, scratch1, &bailout);
 
   // If the array has length zero, return the empty string.
-  __ ldr(array_length, FieldMemOperand(array, JSArray::kLengthOffset));
-  __ SmiUntag(array_length, SetCC);
-  __ b(ne, &non_trivial_array);
-  __ LoadRoot(r0, Heap::kempty_stringRootIndex);
-  __ b(&done);
+  // Load and untag the length of the array.
+  // It is an unsigned value, so we can skip sign extension.
+  // We assume little endianness.
+  __ Ldrsw(array_length,
+           UntagSmiFieldMemOperand(array, JSArray::kLengthOffset));
+  __ Cbnz(array_length, &non_trivial_array);
+  __ LoadRoot(result, Heap::kempty_stringRootIndex);
+  __ B(&done);
 
-  __ bind(&non_trivial_array);
-
+  __ Bind(&non_trivial_array);
   // Get the FixedArray containing array's elements.
-  elements = array;
-  __ ldr(elements, FieldMemOperand(array, JSArray::kElementsOffset));
-  array = no_reg;  // End of array's live range.
+  __ Ldr(elements, FieldMemOperand(array, JSArray::kElementsOffset));
 
   // Check that all array elements are sequential ASCII strings, and
-  // accumulate the sum of their lengths, as a smi-encoded value.
-  __ mov(string_length, Operand::Zero());
-  __ add(element,
-         elements, Operand(FixedArray::kHeaderSize - kHeapObjectTag));
-  __ add(elements_end, element, Operand(array_length, LSL, kPointerSizeLog2));
+  // accumulate the sum of their lengths.
+  __ Mov(string_length, 0);
+  __ Add(element, elements, FixedArray::kHeaderSize - kHeapObjectTag);
+  __ Add(elements_end, element, Operand(array_length, LSL, kPointerSizeLog2));
   // Loop condition: while (element < elements_end).
   // Live values in registers:
   //   elements: Fixed array of strings.
   //   array_length: Length of the fixed array of strings (not smi)
   //   separator: Separator string
-  //   string_length: Accumulated sum of string lengths (smi).
+  //   string_length: Accumulated sum of string lengths (not smi).
   //   element: Current array element.
   //   elements_end: Array end.
-  if (generate_debug_code_) {
-    __ cmp(array_length, Operand::Zero());
+  if (FLAG_debug_code) {
+    __ Cmp(array_length, Operand(0));
     __ Assert(gt, kNoEmptyArraysHereInEmitFastAsciiArrayJoin);
   }
-  __ bind(&loop);
-  __ ldr(string, MemOperand(element, kPointerSize, PostIndex));
+  __ Bind(&loop);
+  __ Ldr(string, MemOperand(element, kPointerSize, PostIndex));
   __ JumpIfSmi(string, &bailout);
-  __ ldr(scratch, FieldMemOperand(string, HeapObject::kMapOffset));
-  __ ldrb(scratch, FieldMemOperand(scratch, Map::kInstanceTypeOffset));
-  __ JumpIfInstanceTypeIsNotSequentialAscii(scratch, scratch, &bailout);
-  __ ldr(scratch, FieldMemOperand(string, SeqOneByteString::kLengthOffset));
-  __ add(string_length, string_length, Operand(scratch), SetCC);
-  __ b(vs, &bailout);
-  __ cmp(element, elements_end);
-  __ b(lt, &loop);
+  __ Ldr(scratch1, FieldMemOperand(string, HeapObject::kMapOffset));
+  __ Ldrb(scratch1, FieldMemOperand(scratch1, Map::kInstanceTypeOffset));
+  __ JumpIfInstanceTypeIsNotSequentialAscii(scratch1, scratch2, &bailout);
+  __ Ldrsw(scratch1,
+           UntagSmiFieldMemOperand(string, SeqOneByteString::kLengthOffset));
+  __ Adds(string_length, string_length, scratch1);
+  __ B(vs, &bailout);
+  __ Cmp(element, elements_end);
+  __ B(lt, &loop);
 
   // If array_length is 1, return elements[0], a string.
-  __ cmp(array_length, Operand(1));
-  __ b(ne, &not_size_one_array);
-  __ ldr(r0, FieldMemOperand(elements, FixedArray::kHeaderSize));
-  __ b(&done);
+  __ Cmp(array_length, 1);
+  __ B(ne, &not_size_one_array);
+  __ Ldr(result, FieldMemOperand(elements, FixedArray::kHeaderSize));
+  __ B(&done);
 
-  __ bind(&not_size_one_array);
+  __ Bind(&not_size_one_array);
 
   // Live values in registers:
   //   separator: Separator string
-  //   array_length: Length of the array.
-  //   string_length: Sum of string lengths (smi).
+  //   array_length: Length of the array (not smi).
+  //   string_length: Sum of string lengths (not smi).
   //   elements: FixedArray of strings.
 
   // Check that the separator is a flat ASCII string.
   __ JumpIfSmi(separator, &bailout);
-  __ ldr(scratch, FieldMemOperand(separator, HeapObject::kMapOffset));
-  __ ldrb(scratch, FieldMemOperand(scratch, Map::kInstanceTypeOffset));
-  __ JumpIfInstanceTypeIsNotSequentialAscii(scratch, scratch, &bailout);
+  __ Ldr(scratch1, FieldMemOperand(separator, HeapObject::kMapOffset));
+  __ Ldrb(scratch1, FieldMemOperand(scratch1, Map::kInstanceTypeOffset));
+  __ JumpIfInstanceTypeIsNotSequentialAscii(scratch1, scratch2, &bailout);
 
   // Add (separator length times array_length) - separator length to the
-  // string_length to get the length of the result string. array_length is not
-  // smi but the other values are, so the result is a smi
-  __ ldr(scratch, FieldMemOperand(separator, SeqOneByteString::kLengthOffset));
-  __ sub(string_length, string_length, Operand(scratch));
-  __ smull(scratch, ip, array_length, scratch);
-  // Check for smi overflow. No overflow if higher 33 bits of 64-bit result are
-  // zero.
-  __ cmp(ip, Operand::Zero());
-  __ b(ne, &bailout);
-  __ tst(scratch, Operand(0x80000000));
-  __ b(ne, &bailout);
-  __ add(string_length, string_length, Operand(scratch), SetCC);
-  __ b(vs, &bailout);
-  __ SmiUntag(string_length);
+  // string_length to get the length of the result string.
+  // Load the separator length as untagged.
+  // We assume little endianness, and that the length is positive.
+  __ Ldrsw(separator_length,
+           UntagSmiFieldMemOperand(separator,
+                                   SeqOneByteString::kLengthOffset));
+  __ Sub(string_length, string_length, separator_length);
+  __ Umaddl(string_length, array_length.W(), separator_length.W(),
+            string_length);
 
-  // Get first element in the array to free up the elements register to be used
-  // for the result.
-  __ add(element,
-         elements, Operand(FixedArray::kHeaderSize - kHeapObjectTag));
-  result = elements;  // End of live range for elements.
-  elements = no_reg;
+  // Get first element in the array.
+  __ Add(element, elements, FixedArray::kHeaderSize - kHeapObjectTag);
   // Live values in registers:
   //   element: First array element
   //   separator: Separator string
   //   string_length: Length of result string (not smi)
-  //   array_length: Length of the array.
-  __ AllocateAsciiString(result,
-                         string_length,
-                         scratch,
-                         string,  // used as scratch
-                         elements_end,  // used as scratch
+  //   array_length: Length of the array (not smi).
+  __ AllocateAsciiString(result, string_length, scratch1, scratch2, scratch3,
                          &bailout);
+
   // Prepare for looping. Set up elements_end to end of the array. Set
   // result_pos to the position of the result where to write the first
   // character.
-  __ add(elements_end, element, Operand(array_length, LSL, kPointerSizeLog2));
-  result_pos = array_length;  // End of live range for array_length.
-  array_length = no_reg;
-  __ add(result_pos,
-         result,
-         Operand(SeqOneByteString::kHeaderSize - kHeapObjectTag));
+  // TODO(all): useless unless AllocateAsciiString trashes the register.
+  __ Add(elements_end, element, Operand(array_length, LSL, kPointerSizeLog2));
+  __ Add(result_pos, result, SeqOneByteString::kHeaderSize - kHeapObjectTag);
 
   // Check the length of the separator.
-  __ ldr(scratch, FieldMemOperand(separator, SeqOneByteString::kLengthOffset));
-  __ cmp(scratch, Operand(Smi::FromInt(1)));
-  __ b(eq, &one_char_separator);
-  __ b(gt, &long_separator);
+  __ Cmp(separator_length, 1);
+  __ B(eq, &one_char_separator);
+  __ B(gt, &long_separator);
 
   // Empty separator case
-  __ bind(&empty_separator_loop);
+  __ Bind(&empty_separator_loop);
   // Live values in registers:
   //   result_pos: the position to which we are currently copying characters.
   //   element: Current array element.
   //   elements_end: Array end.
 
   // Copy next array element to the result.
-  __ ldr(string, MemOperand(element, kPointerSize, PostIndex));
-  __ ldr(string_length, FieldMemOperand(string, String::kLengthOffset));
-  __ SmiUntag(string_length);
-  __ add(string,
-         string,
-         Operand(SeqOneByteString::kHeaderSize - kHeapObjectTag));
-  __ CopyBytes(string, result_pos, string_length, scratch);
-  __ cmp(element, elements_end);
-  __ b(lt, &empty_separator_loop);  // End while (element < elements_end).
-  ASSERT(result.is(r0));
-  __ b(&done);
+  __ Ldr(string, MemOperand(element, kPointerSize, PostIndex));
+  __ Ldrsw(string_length,
+           UntagSmiFieldMemOperand(string, String::kLengthOffset));
+  __ Add(string, string, SeqOneByteString::kHeaderSize - kHeapObjectTag);
+  __ CopyBytes(result_pos, string, string_length, scratch1);
+  __ Cmp(element, elements_end);
+  __ B(lt, &empty_separator_loop);  // End while (element < elements_end).
+  __ B(&done);
 
   // One-character separator case
-  __ bind(&one_char_separator);
+  __ Bind(&one_char_separator);
   // Replace separator with its ASCII character value.
-  __ ldrb(separator, FieldMemOperand(separator, SeqOneByteString::kHeaderSize));
+  __ Ldrb(separator, FieldMemOperand(separator, SeqOneByteString::kHeaderSize));
   // Jump into the loop after the code that copies the separator, so the first
   // element is not preceded by a separator
-  __ jmp(&one_char_separator_loop_entry);
+  __ B(&one_char_separator_loop_entry);
 
-  __ bind(&one_char_separator_loop);
+  __ Bind(&one_char_separator_loop);
   // Live values in registers:
   //   result_pos: the position to which we are currently copying characters.
   //   element: Current array element.
   //   elements_end: Array end.
   //   separator: Single separator ASCII char (in lower byte).
 
   // Copy the separator character to the result.
-  __ strb(separator, MemOperand(result_pos, 1, PostIndex));
+  __ Strb(separator, MemOperand(result_pos, 1, PostIndex));
 
   // Copy next array element to the result.
-  __ bind(&one_char_separator_loop_entry);
-  __ ldr(string, MemOperand(element, kPointerSize, PostIndex));
-  __ ldr(string_length, FieldMemOperand(string, String::kLengthOffset));
-  __ SmiUntag(string_length);
-  __ add(string,
-         string,
-         Operand(SeqOneByteString::kHeaderSize - kHeapObjectTag));
-  __ CopyBytes(string, result_pos, string_length, scratch);
-  __ cmp(element, elements_end);
-  __ b(lt, &one_char_separator_loop);  // End while (element < elements_end).
-  ASSERT(result.is(r0));
-  __ b(&done);
+  __ Bind(&one_char_separator_loop_entry);
+  __ Ldr(string, MemOperand(element, kPointerSize, PostIndex));
+  __ Ldrsw(string_length,
+           UntagSmiFieldMemOperand(string, String::kLengthOffset));
+  __ Add(string, string, SeqOneByteString::kHeaderSize - kHeapObjectTag);
+  __ CopyBytes(result_pos, string, string_length, scratch1);
+  __ Cmp(element, elements_end);
+  __ B(lt, &one_char_separator_loop);  // End while (element < elements_end).
+  __ B(&done);
 
   // Long separator case (separator is more than one character). Entry is at the
   // label long_separator below.
-  __ bind(&long_separator_loop);
+  __ Bind(&long_separator_loop);
   // Live values in registers:
   //   result_pos: the position to which we are currently copying characters.
   //   element: Current array element.
   //   elements_end: Array end.
   //   separator: Separator string.
 
   // Copy the separator to the result.
-  __ ldr(string_length, FieldMemOperand(separator, String::kLengthOffset));
-  __ SmiUntag(string_length);
-  __ add(string,
-         separator,
-         Operand(SeqOneByteString::kHeaderSize - kHeapObjectTag));
-  __ CopyBytes(string, result_pos, string_length, scratch);
+  // TODO(all): hoist next two instructions.
+  __ Ldrsw(string_length,
+           UntagSmiFieldMemOperand(separator, String::kLengthOffset));
+  __ Add(string, separator, SeqOneByteString::kHeaderSize - kHeapObjectTag);
+  __ CopyBytes(result_pos, string, string_length, scratch1);
 
-  __ bind(&long_separator);
-  __ ldr(string, MemOperand(element, kPointerSize, PostIndex));
-  __ ldr(string_length, FieldMemOperand(string, String::kLengthOffset));
-  __ SmiUntag(string_length);
-  __ add(string,
-         string,
-         Operand(SeqOneByteString::kHeaderSize - kHeapObjectTag));
-  __ CopyBytes(string, result_pos, string_length, scratch);
-  __ cmp(element, elements_end);
-  __ b(lt, &long_separator_loop);  // End while (element < elements_end).
-  ASSERT(result.is(r0));
-  __ b(&done);
+  __ Bind(&long_separator);
+  __ Ldr(string, MemOperand(element, kPointerSize, PostIndex));
+  __ Ldrsw(string_length,
+           UntagSmiFieldMemOperand(string, String::kLengthOffset));
+  __ Add(string, string, SeqOneByteString::kHeaderSize - kHeapObjectTag);
+  __ CopyBytes(result_pos, string, string_length, scratch1);
+  __ Cmp(element, elements_end);
+  __ B(lt, &long_separator_loop);  // End while (element < elements_end).
+  __ B(&done);
 
-  __ bind(&bailout);
-  __ LoadRoot(r0, Heap::kUndefinedValueRootIndex);
-  __ bind(&done);
-  context()->Plug(r0);
+  __ Bind(&bailout);
+  // Returning undefined will force slower code to handle it.
+  __ LoadRoot(result, Heap::kUndefinedValueRootIndex);
+  __ Bind(&done);
+  context()->Plug(result);
 }
 
 
 void FullCodeGenerator::VisitCallRuntime(CallRuntime* expr) {
   Handle<String> name = expr->name();
   if (name->length() > 0 && name->Get(0) == '_') {
     Comment cmnt(masm_, "[ InlineRuntimeCall");
     EmitInlineRuntimeCall(expr);
     return;
   }
 
-  Comment cmnt(masm_, "[ CallRuntime");
+  Comment cmnt(masm_, "[ CallRunTime");
   ZoneList<Expression*>* args = expr->arguments();
+  int arg_count = args->length();
 
   if (expr->is_jsruntime()) {
-    // Prepare for calling JS runtime function.
-    __ ldr(r0, GlobalObjectOperand());
-    __ ldr(r0, FieldMemOperand(r0, GlobalObject::kBuiltinsOffset));
-    __ push(r0);
-  }
+    // Push the builtins object as the receiver.
+    __ Ldr(x10, GlobalObjectMemOperand());
+    __ Ldr(x0, FieldMemOperand(x10, GlobalObject::kBuiltinsOffset));
+    __ Push(x0);
 
-  // Push the arguments ("left-to-right").
-  int arg_count = args->length();
-  for (int i = 0; i < arg_count; i++) {
-    VisitForStackValue(args->at(i));
-  }
+    // Load the function from the receiver.
+    __ Mov(x2, Operand(name));
+    CallLoadIC(NOT_CONTEXTUAL, expr->CallRuntimeFeedbackId());
 
-  if (expr->is_jsruntime()) {
-    // Call the JS runtime function.
-    __ mov(r2, Operand(expr->name()));
-    Handle<Code> ic = isolate()->stub_cache()->ComputeCallInitialize(arg_count);
-    CallIC(ic, NOT_CONTEXTUAL, expr->CallRuntimeFeedbackId());
+    // Push the target function under the receiver.
+    __ Pop(x10);
+    __ Push(x0, x10);
+
+    int arg_count = args->length();
+    for (int i = 0; i < arg_count; i++) {
+      VisitForStackValue(args->at(i));
+    }
+
+    // Record source position of the IC call.
+    SetSourcePosition(expr->position());
+    CallFunctionStub stub(arg_count, NO_CALL_FUNCTION_FLAGS);
+    __ Peek(x1, (arg_count + 1) * kPointerSize);
+    __ CallStub(&stub);
+
     // Restore context register.
-    __ ldr(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
+    __ Ldr(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
+
+    context()->DropAndPlug(1, x0);
   } else {
+    // Push the arguments ("left-to-right").
+    for (int i = 0; i < arg_count; i++) {
+      VisitForStackValue(args->at(i));
+    }
+
     // Call the C runtime function.
     __ CallRuntime(expr->function(), arg_count);
+    context()->Plug(x0);
   }
-  context()->Plug(r0);
 }
 
 
 void FullCodeGenerator::VisitUnaryOperation(UnaryOperation* expr) {
   switch (expr->op()) {
     case Token::DELETE: {
       Comment cmnt(masm_, "[ UnaryOperation (DELETE)");
       Property* property = expr->expression()->AsProperty();
       VariableProxy* proxy = expr->expression()->AsVariableProxy();
 
       if (property != NULL) {
         VisitForStackValue(property->obj());
         VisitForStackValue(property->key());
         StrictModeFlag strict_mode_flag = (language_mode() == CLASSIC_MODE)
             ? kNonStrictMode : kStrictMode;
-        __ mov(r1, Operand(Smi::FromInt(strict_mode_flag)));
-        __ push(r1);
+        __ Mov(x10, Operand(Smi::FromInt(strict_mode_flag)));
+        __ Push(x10);
         __ InvokeBuiltin(Builtins::DELETE, CALL_FUNCTION);
-        context()->Plug(r0);
+        context()->Plug(x0);
       } else if (proxy != NULL) {
         Variable* var = proxy->var();
         // Delete of an unqualified identifier is disallowed in strict mode
         // but "delete this" is allowed.
         ASSERT(language_mode() == CLASSIC_MODE || var->is_this());
         if (var->IsUnallocated()) {
-          __ ldr(r2, GlobalObjectOperand());
-          __ mov(r1, Operand(var->name()));
-          __ mov(r0, Operand(Smi::FromInt(kNonStrictMode)));
-          __ Push(r2, r1, r0);
+          __ Ldr(x12, GlobalObjectMemOperand());
+          __ Mov(x11, Operand(var->name()));
+          __ Mov(x10, Operand(Smi::FromInt(kNonStrictMode)));
+          __ Push(x12, x11, x10);
           __ InvokeBuiltin(Builtins::DELETE, CALL_FUNCTION);
-          context()->Plug(r0);
+          context()->Plug(x0);
         } else if (var->IsStackAllocated() || var->IsContextSlot()) {
           // Result of deleting non-global, non-dynamic variables is false.
           // The subexpression does not have side effects.
           context()->Plug(var->is_this());
         } else {
           // Non-global variable.  Call the runtime to try to delete from the
           // context where the variable was introduced.
-          ASSERT(!context_register().is(r2));
-          __ mov(r2, Operand(var->name()));
-          __ Push(context_register(), r2);
+          __ Mov(x2, Operand(var->name()));
+          __ Push(context_register(), x2);
           __ CallRuntime(Runtime::kDeleteContextSlot, 2);
-          context()->Plug(r0);
+          context()->Plug(x0);
         }
       } else {
         // Result of deleting non-property, non-variable reference is true.
         // The subexpression may have side effects.
         VisitForEffect(expr->expression());
         context()->Plug(true);
       }
       break;
+      break;
     }
-
     case Token::VOID: {
       Comment cmnt(masm_, "[ UnaryOperation (VOID)");
       VisitForEffect(expr->expression());
       context()->Plug(Heap::kUndefinedValueRootIndex);
       break;
     }
-
     case Token::NOT: {
       Comment cmnt(masm_, "[ UnaryOperation (NOT)");
       if (context()->IsEffect()) {
         // Unary NOT has no side effects so it's only necessary to visit the
         // subexpression.  Match the optimizing compiler by not branching.
         VisitForEffect(expr->expression());
       } else if (context()->IsTest()) {
         const TestContext* test = TestContext::cast(context());
         // The labels are swapped for the recursive call.
         VisitForControl(expr->expression(),
                         test->false_label(),
                         test->true_label(),
                         test->fall_through());
         context()->Plug(test->true_label(), test->false_label());
       } else {
-        // We handle value contexts explicitly rather than simply visiting
-        // for control and plugging the control flow into the context,
-        // because we need to prepare a pair of extra administrative AST ids
-        // for the optimizing compiler.
         ASSERT(context()->IsAccumulatorValue() || context()->IsStackValue());
+        // TODO(jbramley): This could be much more efficient using (for
+        // example) the CSEL instruction.
         Label materialize_true, materialize_false, done;
         VisitForControl(expr->expression(),
                         &materialize_false,
                         &materialize_true,
                         &materialize_true);
-        __ bind(&materialize_true);
+
+        __ Bind(&materialize_true);
         PrepareForBailoutForId(expr->MaterializeTrueId(), NO_REGISTERS);
-        __ LoadRoot(r0, Heap::kTrueValueRootIndex);
-        if (context()->IsStackValue()) __ push(r0);
-        __ jmp(&done);
-        __ bind(&materialize_false);
+        __ LoadRoot(result_register(), Heap::kTrueValueRootIndex);
+        __ B(&done);
+
+        __ Bind(&materialize_false);
         PrepareForBailoutForId(expr->MaterializeFalseId(), NO_REGISTERS);
-        __ LoadRoot(r0, Heap::kFalseValueRootIndex);
-        if (context()->IsStackValue()) __ push(r0);
-        __ bind(&done);
+        __ LoadRoot(result_register(), Heap::kFalseValueRootIndex);
+        __ B(&done);
+
+        __ Bind(&done);
+        if (context()->IsStackValue()) {
+          __ Push(result_register());
+        }
       }
       break;
     }
-
     case Token::TYPEOF: {
       Comment cmnt(masm_, "[ UnaryOperation (TYPEOF)");
-      { StackValueContext context(this);
+      {
+        StackValueContext context(this);
         VisitForTypeofValue(expr->expression());
       }
       __ CallRuntime(Runtime::kTypeof, 1);
-      context()->Plug(r0);
+      context()->Plug(x0);
       break;
     }
-
     default:
       UNREACHABLE();
   }
 }
 
 
 void FullCodeGenerator::VisitCountOperation(CountOperation* expr) {
   Comment cmnt(masm_, "[ CountOperation");
   SetSourcePosition(expr->position());
 
@@ skipping 17 matching lines @@
   }
 
   // Evaluate expression and get value.
   if (assign_type == VARIABLE) {
     ASSERT(expr->expression()->AsVariableProxy()->var() != NULL);
     AccumulatorValueContext context(this);
     EmitVariableLoad(expr->expression()->AsVariableProxy());
   } else {
     // Reserve space for result of postfix operation.
     if (expr->is_postfix() && !context()->IsEffect()) {
-      __ mov(ip, Operand(Smi::FromInt(0)));
-      __ push(ip);
+      __ Push(xzr);
     }
     if (assign_type == NAMED_PROPERTY) {
       // Put the object both on the stack and in the accumulator.
       VisitForAccumulatorValue(prop->obj());
-      __ push(r0);
+      __ Push(x0);
       EmitNamedPropertyLoad(prop);
     } else {
+      // KEYED_PROPERTY
       VisitForStackValue(prop->obj());
       VisitForAccumulatorValue(prop->key());
-      __ ldr(r1, MemOperand(sp, 0));
-      __ push(r0);
+      __ Peek(x1, 0);
+      __ Push(x0);
       EmitKeyedPropertyLoad(prop);
     }
   }
 
   // We need a second deoptimization point after loading the value
   // in case evaluating the property load my have a side effect.
   if (assign_type == VARIABLE) {
     PrepareForBailout(expr->expression(), TOS_REG);
   } else {
     PrepareForBailoutForId(prop->LoadId(), TOS_REG);
   }
 
   // Inline smi case if we are in a loop.
   Label stub_call, done;
   JumpPatchSite patch_site(masm_);
 
   int count_value = expr->op() == Token::INC ? 1 : -1;
   if (ShouldInlineSmiCase(expr->op())) {
     Label slow;
-    patch_site.EmitJumpIfNotSmi(r0, &slow);
+    patch_site.EmitJumpIfNotSmi(x0, &slow);
 
     // Save result for postfix expressions.
     if (expr->is_postfix()) {
       if (!context()->IsEffect()) {
-        // Save the result on the stack. If we have a named or keyed property
-        // we store the result under the receiver that is currently on top
-        // of the stack.
+        // Save the result on the stack. If we have a named or keyed property we
+        // store the result under the receiver that is currently on top of the
+        // stack.
         switch (assign_type) {
           case VARIABLE:
-            __ push(r0);
+            __ Push(x0);
             break;
           case NAMED_PROPERTY:
-            __ str(r0, MemOperand(sp, kPointerSize));
+            __ Poke(x0, kPointerSize);
             break;
           case KEYED_PROPERTY:
-            __ str(r0, MemOperand(sp, 2 * kPointerSize));
+            __ Poke(x0, kPointerSize * 2);
             break;
         }
       }
     }
 
-    __ add(r0, r0, Operand(Smi::FromInt(count_value)), SetCC);
-    __ b(vc, &done);
+    __ Adds(x0, x0, Operand(Smi::FromInt(count_value)));
+    __ B(vc, &done);
     // Call stub. Undo operation first.
-    __ sub(r0, r0, Operand(Smi::FromInt(count_value)));
-    __ jmp(&stub_call);
-    __ bind(&slow);
+    __ Sub(x0, x0, Operand(Smi::FromInt(count_value)));
+    __ B(&stub_call);
+    __ Bind(&slow);
   }
   ToNumberStub convert_stub;
   __ CallStub(&convert_stub);
 
   // Save result for postfix expressions.
   if (expr->is_postfix()) {
     if (!context()->IsEffect()) {
       // Save the result on the stack. If we have a named or keyed property
       // we store the result under the receiver that is currently on top
       // of the stack.
       switch (assign_type) {
         case VARIABLE:
-          __ push(r0);
+          __ Push(x0);
           break;
         case NAMED_PROPERTY:
-          __ str(r0, MemOperand(sp, kPointerSize));
+          __ Poke(x0, kXRegSizeInBytes);
           break;
         case KEYED_PROPERTY:
-          __ str(r0, MemOperand(sp, 2 * kPointerSize));
+          __ Poke(x0, 2 * kXRegSizeInBytes);
           break;
       }
     }
   }
 
-
-  __ bind(&stub_call);
-  __ mov(r1, r0);
-  __ mov(r0, Operand(Smi::FromInt(count_value)));
+  __ Bind(&stub_call);
+  __ Mov(x1, x0);
+  __ Mov(x0, Operand(Smi::FromInt(count_value)));
 
   // Record position before stub call.
   SetSourcePosition(expr->position());
 
-  BinaryOpICStub stub(Token::ADD, NO_OVERWRITE);
-  CallIC(stub.GetCode(isolate()),
-         NOT_CONTEXTUAL,
-         expr->CountBinOpFeedbackId());
-  patch_site.EmitPatchInfo();
-  __ bind(&done);
+  {
+    Assembler::BlockConstPoolScope scope(masm_);
+    BinaryOpICStub stub(Token::ADD, NO_OVERWRITE);
+    CallIC(stub.GetCode(isolate()), expr->CountBinOpFeedbackId());
+    patch_site.EmitPatchInfo();
+  }
+  __ Bind(&done);
 
-  // Store the value returned in r0.
+  // Store the value returned in x0.
   switch (assign_type) {
     case VARIABLE:
       if (expr->is_postfix()) {
         { EffectContext context(this);
           EmitVariableAssignment(expr->expression()->AsVariableProxy()->var(),
                                  Token::ASSIGN);
           PrepareForBailoutForId(expr->AssignmentId(), TOS_REG);
-          context.Plug(r0);
+          context.Plug(x0);
         }
         // For all contexts except EffectConstant We have the result on
         // top of the stack.
         if (!context()->IsEffect()) {
           context()->PlugTOS();
         }
       } else {
         EmitVariableAssignment(expr->expression()->AsVariableProxy()->var(),
                                Token::ASSIGN);
         PrepareForBailoutForId(expr->AssignmentId(), TOS_REG);
-        context()->Plug(r0);
+        context()->Plug(x0);
       }
       break;
     case NAMED_PROPERTY: {
-      __ mov(r2, Operand(prop->key()->AsLiteral()->value()));
-      __ pop(r1);
-      CallStoreIC(NOT_CONTEXTUAL, expr->CountStoreFeedbackId());
+      __ Mov(x2, Operand(prop->key()->AsLiteral()->value()));
+      __ Pop(x1);
+      CallStoreIC(expr->CountStoreFeedbackId());
       PrepareForBailoutForId(expr->AssignmentId(), TOS_REG);
       if (expr->is_postfix()) {
         if (!context()->IsEffect()) {
           context()->PlugTOS();
         }
       } else {
-        context()->Plug(r0);
+        context()->Plug(x0);
       }
       break;
     }
     case KEYED_PROPERTY: {
-      __ Pop(r2, r1);  // r1 = key. r2 = receiver.
+      __ Pop(x1);  // Key.
+      __ Pop(x2);  // Receiver.
       Handle<Code> ic = is_classic_mode()
           ? isolate()->builtins()->KeyedStoreIC_Initialize()
           : isolate()->builtins()->KeyedStoreIC_Initialize_Strict();
-      CallIC(ic, NOT_CONTEXTUAL, expr->CountStoreFeedbackId());
+      CallIC(ic, expr->CountStoreFeedbackId());
       PrepareForBailoutForId(expr->AssignmentId(), TOS_REG);
       if (expr->is_postfix()) {
         if (!context()->IsEffect()) {
           context()->PlugTOS();
         }
       } else {
-        context()->Plug(r0);
+        context()->Plug(x0);
       }
       break;
     }
   }
 }
 
 
 void FullCodeGenerator::VisitForTypeofValue(Expression* expr) {
   ASSERT(!context()->IsEffect());
   ASSERT(!context()->IsTest());
   VariableProxy* proxy = expr->AsVariableProxy();
   if (proxy != NULL && proxy->var()->IsUnallocated()) {
     Comment cmnt(masm_, "Global variable");
-    __ ldr(r0, GlobalObjectOperand());
-    __ mov(r2, Operand(proxy->name()));
+    __ Ldr(x0, GlobalObjectMemOperand());
+    __ Mov(x2, Operand(proxy->name()));
     // Use a regular load, not a contextual load, to avoid a reference
     // error.
     CallLoadIC(NOT_CONTEXTUAL);
     PrepareForBailout(expr, TOS_REG);
-    context()->Plug(r0);
+    context()->Plug(x0);
   } else if (proxy != NULL && proxy->var()->IsLookupSlot()) {
     Label done, slow;
 
     // Generate code for loading from variables potentially shadowed
     // by eval-introduced variables.
     EmitDynamicLookupFastCase(proxy->var(), INSIDE_TYPEOF, &slow, &done);
 
-    __ bind(&slow);
-    __ mov(r0, Operand(proxy->name()));
-    __ Push(cp, r0);
+    __ Bind(&slow);
+    __ Mov(x0, Operand(proxy->name()));
+    __ Push(cp, x0);
     __ CallRuntime(Runtime::kLoadContextSlotNoReferenceError, 2);
     PrepareForBailout(expr, TOS_REG);
-    __ bind(&done);
+    __ Bind(&done);
 
-    context()->Plug(r0);
+    context()->Plug(x0);
   } else {
     // This expression cannot throw a reference error at the top level.
     VisitInDuplicateContext(expr);
   }
 }
 
 
 void FullCodeGenerator::EmitLiteralCompareTypeof(Expression* expr,
                                                  Expression* sub_expr,
                                                  Handle<String> check) {
+  ASM_LOCATION("FullCodeGenerator::EmitLiteralCompareTypeof");
+  Comment cmnt(masm_, "[ EmitLiteralCompareTypeof");
   Label materialize_true, materialize_false;
   Label* if_true = NULL;
   Label* if_false = NULL;
   Label* fall_through = NULL;
   context()->PrepareTest(&materialize_true, &materialize_false,
                          &if_true, &if_false, &fall_through);
 
   { AccumulatorValueContext context(this);
     VisitForTypeofValue(sub_expr);
   }
   PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
 
   if (check->Equals(isolate()->heap()->number_string())) {
-    __ JumpIfSmi(r0, if_true);
-    __ ldr(r0, FieldMemOperand(r0, HeapObject::kMapOffset));
-    __ LoadRoot(ip, Heap::kHeapNumberMapRootIndex);
-    __ cmp(r0, ip);
+    ASM_LOCATION("FullCodeGenerator::EmitLiteralCompareTypeof number_string");
+    __ JumpIfSmi(x0, if_true);
+    __ Ldr(x0, FieldMemOperand(x0, HeapObject::kMapOffset));
+    __ CompareRoot(x0, Heap::kHeapNumberMapRootIndex);
     Split(eq, if_true, if_false, fall_through);
   } else if (check->Equals(isolate()->heap()->string_string())) {
-    __ JumpIfSmi(r0, if_false);
+    ASM_LOCATION("FullCodeGenerator::EmitLiteralCompareTypeof string_string");
+    __ JumpIfSmi(x0, if_false);
     // Check for undetectable objects => false.
-    __ CompareObjectType(r0, r0, r1, FIRST_NONSTRING_TYPE);
-    __ b(ge, if_false);
-    __ ldrb(r1, FieldMemOperand(r0, Map::kBitFieldOffset));
-    __ tst(r1, Operand(1 << Map::kIsUndetectable));
-    Split(eq, if_true, if_false, fall_through);
+    __ JumpIfObjectType(x0, x0, x1, FIRST_NONSTRING_TYPE, if_false, ge);
+    __ Ldrb(x1, FieldMemOperand(x0, Map::kBitFieldOffset));
+    __ TestAndSplit(x1, 1 << Map::kIsUndetectable, if_true, if_false,
+                    fall_through);
   } else if (check->Equals(isolate()->heap()->symbol_string())) {
-    __ JumpIfSmi(r0, if_false);
-    __ CompareObjectType(r0, r0, r1, SYMBOL_TYPE);
+    ASM_LOCATION("FullCodeGenerator::EmitLiteralCompareTypeof symbol_string");
+    __ JumpIfSmi(x0, if_false);
+    __ CompareObjectType(x0, x0, x1, SYMBOL_TYPE);
     Split(eq, if_true, if_false, fall_through);
   } else if (check->Equals(isolate()->heap()->boolean_string())) {
-    __ CompareRoot(r0, Heap::kTrueValueRootIndex);
-    __ b(eq, if_true);
-    __ CompareRoot(r0, Heap::kFalseValueRootIndex);
+    ASM_LOCATION("FullCodeGenerator::EmitLiteralCompareTypeof boolean_string");
+    __ JumpIfRoot(x0, Heap::kTrueValueRootIndex, if_true);
+    __ CompareRoot(x0, Heap::kFalseValueRootIndex);
     Split(eq, if_true, if_false, fall_through);
   } else if (FLAG_harmony_typeof &&
              check->Equals(isolate()->heap()->null_string())) {
-    __ CompareRoot(r0, Heap::kNullValueRootIndex);
+    ASM_LOCATION("FullCodeGenerator::EmitLiteralCompareTypeof null_string");
+    __ CompareRoot(x0, Heap::kNullValueRootIndex);
     Split(eq, if_true, if_false, fall_through);
   } else if (check->Equals(isolate()->heap()->undefined_string())) {
-    __ CompareRoot(r0, Heap::kUndefinedValueRootIndex);
-    __ b(eq, if_true);
-    __ JumpIfSmi(r0, if_false);
+    ASM_LOCATION(
+        "FullCodeGenerator::EmitLiteralCompareTypeof undefined_string");
+    __ JumpIfRoot(x0, Heap::kUndefinedValueRootIndex, if_true);
+    __ JumpIfSmi(x0, if_false);
     // Check for undetectable objects => true.
-    __ ldr(r0, FieldMemOperand(r0, HeapObject::kMapOffset));
-    __ ldrb(r1, FieldMemOperand(r0, Map::kBitFieldOffset));
-    __ tst(r1, Operand(1 << Map::kIsUndetectable));
-    Split(ne, if_true, if_false, fall_through);
+    __ Ldr(x0, FieldMemOperand(x0, HeapObject::kMapOffset));
+    __ Ldrb(x1, FieldMemOperand(x0, Map::kBitFieldOffset));
+    __ TestAndSplit(x1, 1 << Map::kIsUndetectable, if_false, if_true,
+                    fall_through);
+  } else if (check->Equals(isolate()->heap()->function_string())) {
+    ASM_LOCATION("FullCodeGenerator::EmitLiteralCompareTypeof function_string");
+    __ JumpIfSmi(x0, if_false);
+    STATIC_ASSERT(NUM_OF_CALLABLE_SPEC_OBJECT_TYPES == 2);
+    __ JumpIfObjectType(x0, x10, x11, JS_FUNCTION_TYPE, if_true);
+    __ CompareAndSplit(x11, JS_FUNCTION_PROXY_TYPE, eq, if_true, if_false,
+                       fall_through);
 
-  } else if (check->Equals(isolate()->heap()->function_string())) {
-    __ JumpIfSmi(r0, if_false);
-    STATIC_ASSERT(NUM_OF_CALLABLE_SPEC_OBJECT_TYPES == 2);
-    __ CompareObjectType(r0, r0, r1, JS_FUNCTION_TYPE);
-    __ b(eq, if_true);
-    __ cmp(r1, Operand(JS_FUNCTION_PROXY_TYPE));
-    Split(eq, if_true, if_false, fall_through);
   } else if (check->Equals(isolate()->heap()->object_string())) {
-    __ JumpIfSmi(r0, if_false);
+    ASM_LOCATION("FullCodeGenerator::EmitLiteralCompareTypeof object_string");
+    __ JumpIfSmi(x0, if_false);
     if (!FLAG_harmony_typeof) {
-      __ CompareRoot(r0, Heap::kNullValueRootIndex);
-      __ b(eq, if_true);
+      __ JumpIfRoot(x0, Heap::kNullValueRootIndex, if_true);
     }
     // Check for JS objects => true.
-    __ CompareObjectType(r0, r0, r1, FIRST_NONCALLABLE_SPEC_OBJECT_TYPE);
-    __ b(lt, if_false);
-    __ CompareInstanceType(r0, r1, LAST_NONCALLABLE_SPEC_OBJECT_TYPE);
-    __ b(gt, if_false);
+    Register map = x10;
+    __ JumpIfObjectType(x0, map, x11, FIRST_NONCALLABLE_SPEC_OBJECT_TYPE,
+                        if_false, lt);
+    __ CompareInstanceType(map, x11, LAST_NONCALLABLE_SPEC_OBJECT_TYPE);
+    __ B(gt, if_false);
     // Check for undetectable objects => false.
-    __ ldrb(r1, FieldMemOperand(r0, Map::kBitFieldOffset));
-    __ tst(r1, Operand(1 << Map::kIsUndetectable));
-    Split(eq, if_true, if_false, fall_through);
+    __ Ldrb(x10, FieldMemOperand(map, Map::kBitFieldOffset));
+
+    __ TestAndSplit(x10, 1 << Map::kIsUndetectable, if_true, if_false,
+                    fall_through);
+
   } else {
-    if (if_false != fall_through) __ jmp(if_false);
+    ASM_LOCATION("FullCodeGenerator::EmitLiteralCompareTypeof other");
+    if (if_false != fall_through) __ B(if_false);
   }
   context()->Plug(if_true, if_false);
 }
 
 
 void FullCodeGenerator::VisitCompareOperation(CompareOperation* expr) {
   Comment cmnt(masm_, "[ CompareOperation");
   SetSourcePosition(expr->position());
 
-  // First we try a fast inlined version of the compare when one of
-  // the operands is a literal.
-  if (TryLiteralCompare(expr)) return;
+  // Try to generate an optimized comparison with a literal value.
+  // TODO(jbramley): This only checks common values like NaN or undefined.
+  // Should it also handle A64 immediate operands?
+  if (TryLiteralCompare(expr)) {
+    return;
+  }
 
-  // Always perform the comparison for its control flow.  Pack the result
-  // into the expression's context after the comparison is performed.
-  Label materialize_true, materialize_false;
+  // Assign labels according to context()->PrepareTest.
+  Label materialize_true;
+  Label materialize_false;
   Label* if_true = NULL;
   Label* if_false = NULL;
   Label* fall_through = NULL;
   context()->PrepareTest(&materialize_true, &materialize_false,
                          &if_true, &if_false, &fall_through);
 
   Token::Value op = expr->op();
   VisitForStackValue(expr->left());
   switch (op) {
     case Token::IN:
       VisitForStackValue(expr->right());
       __ InvokeBuiltin(Builtins::IN, CALL_FUNCTION);
       PrepareForBailoutBeforeSplit(expr, false, NULL, NULL);
-      __ LoadRoot(ip, Heap::kTrueValueRootIndex);
-      __ cmp(r0, ip);
+      __ CompareRoot(x0, Heap::kTrueValueRootIndex);
       Split(eq, if_true, if_false, fall_through);
       break;
 
     case Token::INSTANCEOF: {
       VisitForStackValue(expr->right());
       InstanceofStub stub(InstanceofStub::kNoFlags);
       __ CallStub(&stub);
       PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
       // The stub returns 0 for true.
-      __ tst(r0, r0);
-      Split(eq, if_true, if_false, fall_through);
+      __ CompareAndSplit(x0, 0, eq, if_true, if_false, fall_through);
       break;
     }
 
     default: {
       VisitForAccumulatorValue(expr->right());
       Condition cond = CompareIC::ComputeCondition(op);
-      __ pop(r1);
 
-      bool inline_smi_code = ShouldInlineSmiCase(op);
+      // Pop the stack value.
+      __ Pop(x1);
+
       JumpPatchSite patch_site(masm_);
-      if (inline_smi_code) {
+      if (ShouldInlineSmiCase(op)) {
         Label slow_case;
-        __ orr(r2, r0, Operand(r1));
-        patch_site.EmitJumpIfNotSmi(r2, &slow_case);
-        __ cmp(r1, r0);
+        patch_site.EmitJumpIfEitherNotSmi(x0, x1, &slow_case);
+        __ Cmp(x1, x0);
         Split(cond, if_true, if_false, NULL);
-        __ bind(&slow_case);
+        __ Bind(&slow_case);
       }
 
       // Record position and call the compare IC.
       SetSourcePosition(expr->position());
       Handle<Code> ic = CompareIC::GetUninitialized(isolate(), op);
-      CallIC(ic, NOT_CONTEXTUAL, expr->CompareOperationFeedbackId());
+      CallIC(ic, expr->CompareOperationFeedbackId());
       patch_site.EmitPatchInfo();
       PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
-      __ cmp(r0, Operand::Zero());
-      Split(cond, if_true, if_false, fall_through);
+      __ CompareAndSplit(x0, 0, cond, if_true, if_false, fall_through);
     }
   }
 
   // Convert the result of the comparison into one expected for this
   // expression's context.
   context()->Plug(if_true, if_false);
 }
 
 
 void FullCodeGenerator::EmitLiteralCompareNil(CompareOperation* expr,
                                               Expression* sub_expr,
                                               NilValue nil) {
+  ASM_LOCATION("FullCodeGenerator::EmitLiteralCompareNil");
   Label materialize_true, materialize_false;
   Label* if_true = NULL;
   Label* if_false = NULL;
   Label* fall_through = NULL;
   context()->PrepareTest(&materialize_true, &materialize_false,
                          &if_true, &if_false, &fall_through);
 
   VisitForAccumulatorValue(sub_expr);
   PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
+
   if (expr->op() == Token::EQ_STRICT) {
     Heap::RootListIndex nil_value = nil == kNullValue ?
         Heap::kNullValueRootIndex :
         Heap::kUndefinedValueRootIndex;
-    __ LoadRoot(r1, nil_value);
-    __ cmp(r0, r1);
+    __ CompareRoot(x0, nil_value);
     Split(eq, if_true, if_false, fall_through);
   } else {
     Handle<Code> ic = CompareNilICStub::GetUninitialized(isolate(), nil);
-    CallIC(ic, NOT_CONTEXTUAL, expr->CompareOperationFeedbackId());
-    __ cmp(r0, Operand(0));
-    Split(ne, if_true, if_false, fall_through);
+    CallIC(ic, expr->CompareOperationFeedbackId());
+    __ CompareAndSplit(x0, 0, ne, if_true, if_false, fall_through);
   }
+
   context()->Plug(if_true, if_false);
 }
 
 
 void FullCodeGenerator::VisitThisFunction(ThisFunction* expr) {
-  __ ldr(r0, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset));
-  context()->Plug(r0);
-}
-
-
+  __ Ldr(x0, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset));
+  context()->Plug(x0);
+}
+
+
+void FullCodeGenerator::VisitYield(Yield* expr) {
+  Comment cmnt(masm_, "[ Yield");
+  // Evaluate yielded value first; the initial iterator definition depends on
+  // this. It stays on the stack while we update the iterator.
+  VisitForStackValue(expr->expression());
+
+  // TODO(jbramley): Tidy this up once the merge is done, using named registers
+  // and suchlike. The implementation changes a little by bleeding_edge so I
+  // don't want to spend too much time on it now.
+
+  switch (expr->yield_kind()) {
+    case Yield::SUSPEND:
+      // Pop value from top-of-stack slot; box result into result register.
+      EmitCreateIteratorResult(false);
+      __ Push(result_register());
+      // Fall through.
+    case Yield::INITIAL: {
+      Label suspend, continuation, post_runtime, resume;
+
+      __ B(&suspend);
+
+      // TODO(jbramley): This label is bound here because the following code
+      // looks at its pos(). Is it possible to do something more efficient here,
+      // perhaps using Adr?
+      __ Bind(&continuation);
+      __ B(&resume);
+
+      __ Bind(&suspend);
+      VisitForAccumulatorValue(expr->generator_object());
+      ASSERT((continuation.pos() > 0) && Smi::IsValid(continuation.pos()));
+      __ Mov(x1, Operand(Smi::FromInt(continuation.pos())));
+      __ Str(x1, FieldMemOperand(x0, JSGeneratorObject::kContinuationOffset));
+      __ Str(cp, FieldMemOperand(x0, JSGeneratorObject::kContextOffset));
+      __ Mov(x1, cp);
+      __ RecordWriteField(x0, JSGeneratorObject::kContextOffset, x1, x2,
+                          kLRHasBeenSaved, kDontSaveFPRegs);
+      __ Add(x1, fp, StandardFrameConstants::kExpressionsOffset);
+      __ Cmp(__ StackPointer(), x1);
+      __ B(eq, &post_runtime);
+      __ Push(x0);  // generator object
+      __ CallRuntime(Runtime::kSuspendJSGeneratorObject, 1);
+      __ Ldr(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
+      __ Bind(&post_runtime);
+      __ Pop(result_register());
+      EmitReturnSequence();
+
+      __ Bind(&resume);
+      context()->Plug(result_register());
+      break;
+    }
+
+    case Yield::FINAL: {
+      VisitForAccumulatorValue(expr->generator_object());
+      __ Mov(x1, Operand(Smi::FromInt(JSGeneratorObject::kGeneratorClosed)));
+      __ Str(x1, FieldMemOperand(result_register(),
+                                 JSGeneratorObject::kContinuationOffset));
+      // Pop value from top-of-stack slot, box result into result register.
+      EmitCreateIteratorResult(true);
+      EmitUnwindBeforeReturn();
+      EmitReturnSequence();
+      break;
+    }
+
+    case Yield::DELEGATING: {
+      VisitForStackValue(expr->generator_object());
+
+      // Initial stack layout is as follows:
+      // [sp + 1 * kPointerSize] iter
+      // [sp + 0 * kPointerSize] g
+
+      Label l_catch, l_try, l_suspend, l_continuation, l_resume;
+      Label l_next, l_call, l_loop;
+      // Initial send value is undefined.
+      __ LoadRoot(x0, Heap::kUndefinedValueRootIndex);
+      __ B(&l_next);
+
+      // catch (e) { receiver = iter; f = 'throw'; arg = e; goto l_call; }
+      __ Bind(&l_catch);
+      handler_table()->set(expr->index(), Smi::FromInt(l_catch.pos()));
+      __ LoadRoot(x2, Heap::kthrow_stringRootIndex);  // "throw"
+      __ Peek(x3, 1 * kPointerSize);                  // iter
+      __ Push(x2, x3, x0);                            // "throw", iter, except
+      __ B(&l_call);
+
+      // try { received = %yield result }
+      // Shuffle the received result above a try handler and yield it without
+      // re-boxing.
+      __ Bind(&l_try);
+      __ Pop(x0);                                        // result
+      __ PushTryHandler(StackHandler::CATCH, expr->index());
+      const int handler_size = StackHandlerConstants::kSize;
+      __ Push(x0);                                       // result
+      __ B(&l_suspend);
+
+      // TODO(jbramley): This label is bound here because the following code
+      // looks at its pos(). Is it possible to do something more efficient here,
+      // perhaps using Adr?
+      __ Bind(&l_continuation);
+      __ B(&l_resume);
+
+      __ Bind(&l_suspend);
+      const int generator_object_depth = kPointerSize + handler_size;
+      __ Peek(x0, generator_object_depth);
+      __ Push(x0);                                       // g
+      ASSERT((l_continuation.pos() > 0) && Smi::IsValid(l_continuation.pos()));
+      __ Mov(x1, Operand(Smi::FromInt(l_continuation.pos())));
+      __ Str(x1, FieldMemOperand(x0, JSGeneratorObject::kContinuationOffset));
+      __ Str(cp, FieldMemOperand(x0, JSGeneratorObject::kContextOffset));
+      __ Mov(x1, cp);
+      __ RecordWriteField(x0, JSGeneratorObject::kContextOffset, x1, x2,
+                          kLRHasBeenSaved, kDontSaveFPRegs);
+      __ CallRuntime(Runtime::kSuspendJSGeneratorObject, 1);
+      __ Ldr(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
+      __ Pop(x0);                                        // result
+      EmitReturnSequence();
+      __ Bind(&l_resume);                                // received in x0
+      __ PopTryHandler();
+
+      // receiver = iter; f = 'next'; arg = received;
+      __ Bind(&l_next);
+      __ LoadRoot(x2, Heap::knext_stringRootIndex);  // "next"
+      __ Peek(x3, 1 * kPointerSize);                 // iter
+      __ Push(x2, x3, x0);                           // "next", iter, received
+
+      // result = receiver[f](arg);
+      __ Bind(&l_call);
+      __ Peek(x1, 1 * kPointerSize);
+      __ Peek(x0, 2 * kPointerSize);
+      Handle<Code> ic = isolate()->builtins()->KeyedLoadIC_Initialize();
+      CallIC(ic, TypeFeedbackId::None());
+      __ Mov(x1, x0);
+      __ Poke(x1, 2 * kPointerSize);
+      CallFunctionStub stub(1, CALL_AS_METHOD);
+      __ CallStub(&stub);
+
+      __ Ldr(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
+      __ Drop(1);  // The function is still on the stack; drop it.
+
+      // if (!result.done) goto l_try;
+      __ Bind(&l_loop);
+      __ Push(x0);                                       // save result
+      __ LoadRoot(x2, Heap::kdone_stringRootIndex);      // "done"
+      CallLoadIC(NOT_CONTEXTUAL);                        // result.done in x0
+      // The ToBooleanStub argument (result.done) is in x0.
+      Handle<Code> bool_ic = ToBooleanStub::GetUninitialized(isolate());
+      CallIC(bool_ic);
+      __ Cbz(x0, &l_try);
+
+      // result.value
+      __ Pop(x0);                                        // result
+      __ LoadRoot(x2, Heap::kvalue_stringRootIndex);     // "value"
+      CallLoadIC(NOT_CONTEXTUAL);                        // result.value in x0
+      context()->DropAndPlug(2, x0);                     // drop iter and g
+      break;
+    }
+  }
+}
+
+
+void FullCodeGenerator::EmitGeneratorResume(Expression *generator,
+    Expression *value,
+    JSGeneratorObject::ResumeMode resume_mode) {
+  ASM_LOCATION("FullCodeGenerator::EmitGeneratorResume");
+  Register value_reg = x0;
+  Register generator_object = x1;
+  Register the_hole = x2;
+  Register operand_stack_size = w3;
+  Register function = x4;
+
+  // The value stays in x0, and is ultimately read by the resumed generator, as
+  // if the CallRuntime(Runtime::kSuspendJSGeneratorObject) returned it. Or it
+  // is read to throw the value when the resumed generator is already closed. r1
+  // will hold the generator object until the activation has been resumed.
+  VisitForStackValue(generator);
+  VisitForAccumulatorValue(value);
+  __ Pop(generator_object);
+
+  // Check generator state.
+  Label wrong_state, closed_state, done;
+  __ Ldr(x10, FieldMemOperand(generator_object,
+                              JSGeneratorObject::kContinuationOffset));
+  STATIC_ASSERT(JSGeneratorObject::kGeneratorExecuting < 0);
+  STATIC_ASSERT(JSGeneratorObject::kGeneratorClosed == 0);
+  __ CompareAndBranch(x10, Operand(Smi::FromInt(0)), eq, &closed_state);
+  __ CompareAndBranch(x10, Operand(Smi::FromInt(0)), lt, &wrong_state);
+
+  // Load suspended function and context.
+  __ Ldr(cp, FieldMemOperand(generator_object,
+                             JSGeneratorObject::kContextOffset));
+  __ Ldr(function, FieldMemOperand(generator_object,
+                                   JSGeneratorObject::kFunctionOffset));
+
+  // Load receiver and store as the first argument.
+  __ Ldr(x10, FieldMemOperand(generator_object,
+                              JSGeneratorObject::kReceiverOffset));
+  __ Push(x10);
+
+  // Push holes for the rest of the arguments to the generator function.
+  __ Ldr(x10, FieldMemOperand(function, JSFunction::kSharedFunctionInfoOffset));
+
+  // The number of arguments is stored as an int32_t, and -1 is a marker
+  // (SharedFunctionInfo::kDontAdaptArgumentsSentinel), so we need sign
+  // extension to correctly handle it. However, in this case, we operate on
+  // 32-bit W registers, so extension isn't required.
+  __ Ldr(w10, FieldMemOperand(x10,
+                              SharedFunctionInfo::kFormalParameterCountOffset));
+  __ LoadRoot(the_hole, Heap::kTheHoleValueRootIndex);
+  __ PushMultipleTimes(the_hole, w10);
+
+  // Enter a new JavaScript frame, and initialize its slots as they were when
+  // the generator was suspended.
+  Label resume_frame;
+  __ Bl(&resume_frame);
+  __ B(&done);
+
+  __ Bind(&resume_frame);
+  __ Push(lr,           // Return address.
+          fp,           // Caller's frame pointer.
+          cp,           // Callee's context.
+          function);    // Callee's JS Function.
+  __ Add(fp, __ StackPointer(), kPointerSize * 2);
+
+  // Load and untag the operand stack size.
+  __ Ldr(x10, FieldMemOperand(generator_object,
+                              JSGeneratorObject::kOperandStackOffset));
+  __ Ldr(operand_stack_size,
+         UntagSmiFieldMemOperand(x10, FixedArray::kLengthOffset));
+
+  // If we are sending a value and there is no operand stack, we can jump back
+  // in directly.
+  if (resume_mode == JSGeneratorObject::NEXT) {
+    Label slow_resume;
+    __ Cbnz(operand_stack_size, &slow_resume);
+    __ Ldr(x10, FieldMemOperand(function, JSFunction::kCodeEntryOffset));
+    __ Ldrsw(x11,
+             UntagSmiFieldMemOperand(generator_object,
+                                     JSGeneratorObject::kContinuationOffset));
+    __ Add(x10, x10, x11);
+    __ Mov(x12, Operand(Smi::FromInt(JSGeneratorObject::kGeneratorExecuting)));
+    __ Str(x12, FieldMemOperand(generator_object,
+                                JSGeneratorObject::kContinuationOffset));
+    __ Br(x10);
+
+    __ Bind(&slow_resume);
+  }
+
+  // Otherwise, we push holes for the operand stack and call the runtime to fix
+  // up the stack and the handlers.
+  __ PushMultipleTimes(the_hole, operand_stack_size);
+
+  __ Mov(x10, Operand(Smi::FromInt(resume_mode)));
+  __ Push(generator_object, result_register(), x10);
+  __ CallRuntime(Runtime::kResumeJSGeneratorObject, 3);
+  // Not reached: the runtime call returns elsewhere.
+  __ Unreachable();
+
+  // Reach here when generator is closed.
+  __ Bind(&closed_state);
+  if (resume_mode == JSGeneratorObject::NEXT) {
+    // Return completed iterator result when generator is closed.
+    __ LoadRoot(x10, Heap::kUndefinedValueRootIndex);
+    __ Push(x10);
+    // Pop value from top-of-stack slot; box result into result register.
+    EmitCreateIteratorResult(true);
+  } else {
+    // Throw the provided value.
+    __ Push(value_reg);
+    __ CallRuntime(Runtime::kThrow, 1);
+  }
+  __ B(&done);
+
+  // Throw error if we attempt to operate on a running generator.
+  __ Bind(&wrong_state);
+  __ Push(generator_object);
+  __ CallRuntime(Runtime::kThrowGeneratorStateError, 1);
+
+  __ Bind(&done);
+  context()->Plug(result_register());
+}
+
+
+void FullCodeGenerator::EmitCreateIteratorResult(bool done) {
+  Label gc_required;
+  Label allocated;
+
+  Handle<Map> map(isolate()->native_context()->generator_result_map());
+
+  // Allocate and populate an object with this form: { value: VAL, done: DONE }
+
+  Register result = x0;
+  __ Allocate(map->instance_size(), result, x10, x11, &gc_required, TAG_OBJECT);
+  __ B(&allocated);
+
+  __ Bind(&gc_required);
+  __ Push(Smi::FromInt(map->instance_size()));
+  __ CallRuntime(Runtime::kAllocateInNewSpace, 1);
+  __ Ldr(context_register(),
+         MemOperand(fp, StandardFrameConstants::kContextOffset));
+
+  __ Bind(&allocated);
+  Register map_reg = x1;
+  Register result_value = x2;
+  Register boolean_done = x3;
+  Register empty_fixed_array = x4;
+  __ Mov(map_reg, Operand(map));
+  __ Pop(result_value);
+  __ Mov(boolean_done, Operand(isolate()->factory()->ToBoolean(done)));
+  __ Mov(empty_fixed_array, Operand(isolate()->factory()->empty_fixed_array()));
+  ASSERT_EQ(map->instance_size(), 5 * kPointerSize);
+  // TODO(jbramley): Use Stp if possible.
+  __ Str(map_reg, FieldMemOperand(result, HeapObject::kMapOffset));
+  __ Str(empty_fixed_array,
+         FieldMemOperand(result, JSObject::kPropertiesOffset));
+  __ Str(empty_fixed_array, FieldMemOperand(result, JSObject::kElementsOffset));
+  __ Str(result_value,
+         FieldMemOperand(result,
+                         JSGeneratorObject::kResultValuePropertyOffset));
+  __ Str(boolean_done,
+         FieldMemOperand(result,
+                         JSGeneratorObject::kResultDonePropertyOffset));
+
+  // Only the value field needs a write barrier, as the other values are in the
+  // root set.
+  __ RecordWriteField(result, JSGeneratorObject::kResultValuePropertyOffset,
+                      x10, x11, kLRHasBeenSaved, kDontSaveFPRegs);
+}
+
+
+// TODO(all): I don't like this method.
+// It seems to me that in too many places x0 is used in place of this.
+// Also, this function is not suitable for all places where x0 should be
+// abstracted (eg. when used as an argument). But some places assume that the
+// first argument register is x0, and use this function instead.
+// Considering that most of the register allocation is hard-coded in the
+// FullCodeGen, that it is unlikely we will need to change it extensively, and
+// that abstracting the allocation through functions would not yield any
+// performance benefit, I think the existence of this function is debatable.
 Register FullCodeGenerator::result_register() {
-  return r0;
-}
-
-
+  return x0;
+}
+
+
 Register FullCodeGenerator::context_register() {
   return cp;
 }
 
 
 void FullCodeGenerator::StoreToFrameField(int frame_offset, Register value) {
-  ASSERT_EQ(POINTER_SIZE_ALIGN(frame_offset), frame_offset);
-  __ str(value, MemOperand(fp, frame_offset));
+  ASSERT(POINTER_SIZE_ALIGN(frame_offset) == frame_offset);
+  __ Str(value, MemOperand(fp, frame_offset));
 }
 
 
 void FullCodeGenerator::LoadContextField(Register dst, int context_index) {
-  __ ldr(dst, ContextOperand(cp, context_index));
+  __ Ldr(dst, ContextMemOperand(cp, context_index));
 }
 
 
 void FullCodeGenerator::PushFunctionArgumentForContextAllocation() {
   Scope* declaration_scope = scope()->DeclarationScope();
   if (declaration_scope->is_global_scope() ||
       declaration_scope->is_module_scope()) {
     // Contexts nested in the native context have a canonical empty function
     // as their closure, not the anonymous closure containing the global
     // code.  Pass a smi sentinel and let the runtime look up the empty
     // function.
-    __ mov(ip, Operand(Smi::FromInt(0)));
+    ASSERT(kSmiTag == 0);
+    __ Push(xzr);
   } else if (declaration_scope->is_eval_scope()) {
     // Contexts created by a call to eval have the same closure as the
     // context calling eval, not the anonymous closure containing the eval
     // code.  Fetch it from the context.
-    __ ldr(ip, ContextOperand(cp, Context::CLOSURE_INDEX));
+    __ Ldr(x10, ContextMemOperand(cp, Context::CLOSURE_INDEX));
+    __ Push(x10);
   } else {
     ASSERT(declaration_scope->is_function_scope());
-    __ ldr(ip, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset));
+    __ Ldr(x10, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset));
+    __ Push(x10);
   }
-  __ push(ip);
 }
 
 
-// ----------------------------------------------------------------------------
-// Non-local control flow support.
-
 void FullCodeGenerator::EnterFinallyBlock() {
-  ASSERT(!result_register().is(r1));
-  // Store result register while executing finally block.
-  __ push(result_register());
-  // Cook return address in link register to stack (smi encoded Code* delta)
-  __ sub(r1, lr, Operand(masm_->CodeObject()));
-  __ SmiTag(r1);
-
-  // Store result register while executing finally block.
-  __ push(r1);
+  ASM_LOCATION("FullCodeGenerator::EnterFinallyBlock");
+  ASSERT(!result_register().is(x10));
+  // Preserve the result register while executing finally block.
+  // Also cook the return address in lr to the stack (smi encoded Code* delta).
+  __ Sub(x10, lr, Operand(masm_->CodeObject()));
+  __ SmiTag(x10);
+  __ Push(result_register(), x10);
 
   // Store pending message while executing finally block.
   ExternalReference pending_message_obj =
       ExternalReference::address_of_pending_message_obj(isolate());
-  __ mov(ip, Operand(pending_message_obj));
-  __ ldr(r1, MemOperand(ip));
-  __ push(r1);
+  __ Mov(x10, Operand(pending_message_obj));
+  __ Ldr(x10, MemOperand(x10));
 
   ExternalReference has_pending_message =
       ExternalReference::address_of_has_pending_message(isolate());
-  __ mov(ip, Operand(has_pending_message));
-  __ ldr(r1, MemOperand(ip));
-  __ SmiTag(r1);
-  __ push(r1);
+  __ Mov(x11, Operand(has_pending_message));
+  __ Ldr(x11, MemOperand(x11));
+  __ SmiTag(x11);
+
+  __ Push(x10, x11);
 
   ExternalReference pending_message_script =
       ExternalReference::address_of_pending_message_script(isolate());
-  __ mov(ip, Operand(pending_message_script));
-  __ ldr(r1, MemOperand(ip));
-  __ push(r1);
+  __ Mov(x10, Operand(pending_message_script));
+  __ Ldr(x10, MemOperand(x10));
+  __ Push(x10);
 }
 
 
 void FullCodeGenerator::ExitFinallyBlock() {
-  ASSERT(!result_register().is(r1));
+  ASM_LOCATION("FullCodeGenerator::ExitFinallyBlock");
+  ASSERT(!result_register().is(x10));
+
   // Restore pending message from stack.
-  __ pop(r1);
+  __ Pop(x10, x11, x12);
   ExternalReference pending_message_script =
       ExternalReference::address_of_pending_message_script(isolate());
-  __ mov(ip, Operand(pending_message_script));
-  __ str(r1, MemOperand(ip));
+  __ Mov(x13, Operand(pending_message_script));
+  __ Str(x10, MemOperand(x13));
 
-  __ pop(r1);
-  __ SmiUntag(r1);
+  __ SmiUntag(x11);
   ExternalReference has_pending_message =
       ExternalReference::address_of_has_pending_message(isolate());
-  __ mov(ip, Operand(has_pending_message));
-  __ str(r1, MemOperand(ip));
+  __ Mov(x13, Operand(has_pending_message));
+  __ Str(x11, MemOperand(x13));
 
-  __ pop(r1);
   ExternalReference pending_message_obj =
       ExternalReference::address_of_pending_message_obj(isolate());
-  __ mov(ip, Operand(pending_message_obj));
-  __ str(r1, MemOperand(ip));
+  __ Mov(x13, Operand(pending_message_obj));
+  __ Str(x12, MemOperand(x13));
 
-  // Restore result register from stack.
-  __ pop(r1);
+  // Restore result register and cooked return address from the stack.
+  __ Pop(x10, result_register());
 
-  // Uncook return address and return.
-  __ pop(result_register());
-  __ SmiUntag(r1);
-  __ add(pc, r1, Operand(masm_->CodeObject()));
-}
-
-
-#undef __
-
-#define __ ACCESS_MASM(masm())
-
-FullCodeGenerator::NestedStatement* FullCodeGenerator::TryFinally::Exit(
-    int* stack_depth,
-    int* context_length) {
-  // The macros used here must preserve the result register.
-
-  // Because the handler block contains the context of the finally
-  // code, we can restore it directly from there for the finally code
-  // rather than iteratively unwinding contexts via their previous
-  // links.
-  __ Drop(*stack_depth);  // Down to the handler block.
-  if (*context_length > 0) {
-    // Restore the context to its dedicated register and the stack.
-    __ ldr(cp, MemOperand(sp, StackHandlerConstants::kContextOffset));
-    __ str(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
-  }
-  __ PopTryHandler();
-  __ bl(finally_entry_);
-
-  *stack_depth = 0;
-  *context_length = 0;
-  return previous_;
+  // Uncook the return address (see EnterFinallyBlock).
+  __ SmiUntag(x10);
+  __ Add(x11, x10, Operand(masm_->CodeObject()));
+  __ Br(x11);
 }
 
 
 #undef __
 
 
-static const int32_t kBranchBeforeInterrupt =  0x5a000004;
-
-
 void BackEdgeTable::PatchAt(Code* unoptimized_code,
                             Address pc,
                             BackEdgeState target_state,
                             Code* replacement_code) {
-  static const int kInstrSize = Assembler::kInstrSize;
-  Address branch_address = pc - 3 * kInstrSize;
-  CodePatcher patcher(branch_address, 1);
+  // Turn the jump into a nop.
+  Address branch_address = pc - 3 * kInstructionSize;
+  PatchingAssembler patcher(branch_address, 1);
 
   switch (target_state) {
     case INTERRUPT:
       //  <decrement profiling counter>
-      //  2a 00 00 01       bpl ok
-      //  e5 9f c? ??       ldr ip, [pc, <interrupt stub address>]
-      //  e1 2f ff 3c       blx ip
+      //  .. .. .. ..       b.pl ok
+      //  .. .. .. ..       ldr x16, pc+<interrupt stub address>
+      //  .. .. .. ..       blr x16
+      //  ... more instructions.
       //  ok-label
-      patcher.masm()->b(4 * kInstrSize, pl);  // Jump offset is 4 instructions.
-      ASSERT_EQ(kBranchBeforeInterrupt, Memory::int32_at(branch_address));
+      // Jump offset is 6 instructions.
+      ASSERT(Instruction::Cast(branch_address)
+                 ->IsNop(Assembler::INTERRUPT_CODE_NOP));
+      patcher.b(6, pl);
       break;
     case ON_STACK_REPLACEMENT:
     case OSR_AFTER_STACK_CHECK:
       //  <decrement profiling counter>
-      //  e1 a0 00 00       mov r0, r0 (NOP)
-      //  e5 9f c? ??       ldr ip, [pc, <on-stack replacement address>]
-      //  e1 2f ff 3c       blx ip
-      //  ok-label
-      patcher.masm()->nop();
+      //  .. .. .. ..       mov x0, x0 (NOP)
+      //  .. .. .. ..       ldr x16, pc+<on-stack replacement address>
+      //  .. .. .. ..       blr x16
+      ASSERT(Instruction::Cast(branch_address)->IsCondBranchImm());
+      ASSERT(Instruction::Cast(branch_address)->ImmPCOffset() ==
+             6 * kInstructionSize);
+      patcher.nop(Assembler::INTERRUPT_CODE_NOP);
       break;
   }
 
-  Address pc_immediate_load_address = pc - 2 * kInstrSize;
   // Replace the call address.
-  uint32_t interrupt_address_offset =
-      Memory::uint16_at(pc_immediate_load_address) & 0xfff;
-  Address interrupt_address_pointer = pc + interrupt_address_offset;
-  Memory::uint32_at(interrupt_address_pointer) =
-      reinterpret_cast<uint32_t>(replacement_code->entry());
+  Instruction* load = Instruction::Cast(pc)->preceding(2);
+  Address interrupt_address_pointer =
+      reinterpret_cast<Address>(load) + load->ImmPCOffset();
+  ASSERT((Memory::uint64_at(interrupt_address_pointer) ==
+          reinterpret_cast<uint64_t>(unoptimized_code->GetIsolate()
+                                         ->builtins()
+                                         ->OnStackReplacement()
+                                         ->entry())) ||
+         (Memory::uint64_at(interrupt_address_pointer) ==
+          reinterpret_cast<uint64_t>(unoptimized_code->GetIsolate()
+                                         ->builtins()
+                                         ->InterruptCheck()
+                                         ->entry())) ||
+         (Memory::uint64_at(interrupt_address_pointer) ==
+          reinterpret_cast<uint64_t>(unoptimized_code->GetIsolate()
+                                         ->builtins()
+                                         ->OsrAfterStackCheck()
+                                         ->entry())) ||
+         (Memory::uint64_at(interrupt_address_pointer) ==
+          reinterpret_cast<uint64_t>(unoptimized_code->GetIsolate()
+                                         ->builtins()
+                                         ->OnStackReplacement()
+                                         ->entry())));
+  Memory::uint64_at(interrupt_address_pointer) =
+      reinterpret_cast<uint64_t>(replacement_code->entry());
 
   unoptimized_code->GetHeap()->incremental_marking()->RecordCodeTargetPatch(
-      unoptimized_code, pc_immediate_load_address, replacement_code);
+      unoptimized_code, reinterpret_cast<Address>(load), replacement_code);
 }
 
 
 BackEdgeTable::BackEdgeState BackEdgeTable::GetBackEdgeState(
     Isolate* isolate,
     Code* unoptimized_code,
     Address pc) {
-  static const int kInstrSize = Assembler::kInstrSize;
-  ASSERT(Memory::int32_at(pc - kInstrSize) == kBlxIp);
+  // TODO(jbramley): There should be some extra assertions here (as in the ARM
+  // back-end), but this function is gone in bleeding_edge so it might not
+  // matter anyway.
+  Instruction* jump_or_nop = Instruction::Cast(pc)->preceding(3);
 
-  Address branch_address = pc - 3 * kInstrSize;
-  Address pc_immediate_load_address = pc - 2 * kInstrSize;
-  uint32_t interrupt_address_offset =
-      Memory::uint16_at(pc_immediate_load_address) & 0xfff;
-  Address interrupt_address_pointer = pc + interrupt_address_offset;
-
-  if (Memory::int32_at(branch_address) == kBranchBeforeInterrupt) {
-    ASSERT(Memory::uint32_at(interrupt_address_pointer) ==
-           reinterpret_cast<uint32_t>(
-               isolate->builtins()->InterruptCheck()->entry()));
-    ASSERT(Assembler::IsLdrPcImmediateOffset(
-               Assembler::instr_at(pc_immediate_load_address)));
-    return INTERRUPT;
+  if (jump_or_nop->IsNop(Assembler::INTERRUPT_CODE_NOP)) {
+    Instruction* load = Instruction::Cast(pc)->preceding(2);
+    uint64_t entry = Memory::uint64_at(reinterpret_cast<Address>(load) +
+                                       load->ImmPCOffset());
+    if (entry == reinterpret_cast<uint64_t>(
+        isolate->builtins()->OnStackReplacement()->entry())) {
+      return ON_STACK_REPLACEMENT;
+    } else if (entry == reinterpret_cast<uint64_t>(
+        isolate->builtins()->OsrAfterStackCheck()->entry())) {
+      return OSR_AFTER_STACK_CHECK;
+    } else {
+      UNREACHABLE();
+    }
   }
 
-  ASSERT(Assembler::IsNop(Assembler::instr_at(branch_address)));
-  ASSERT(Assembler::IsLdrPcImmediateOffset(
-             Assembler::instr_at(pc_immediate_load_address)));
+  return INTERRUPT;
+}
 
-  if (Memory::uint32_at(interrupt_address_pointer) ==
-      reinterpret_cast<uint32_t>(
-          isolate->builtins()->OnStackReplacement()->entry())) {
-    return ON_STACK_REPLACEMENT;
+
+#define __ ACCESS_MASM(masm())
+
+
+FullCodeGenerator::NestedStatement* FullCodeGenerator::TryFinally::Exit(
+    int* stack_depth,
+    int* context_length) {
+  ASM_LOCATION("FullCodeGenerator::TryFinally::Exit");
+  // The macros used here must preserve the result register.
+
+  // Because the handler block contains the context of the finally
+  // code, we can restore it directly from there for the finally code
+  // rather than iteratively unwinding contexts via their previous
+  // links.
+  __ Drop(*stack_depth);  // Down to the handler block.
+  if (*context_length > 0) {
+    // Restore the context to its dedicated register and the stack.
+    __ Peek(cp, StackHandlerConstants::kContextOffset);
+    __ Str(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
   }
+  __ PopTryHandler();
+  __ Bl(finally_entry_);
 
-  ASSERT(Memory::uint32_at(interrupt_address_pointer) ==
-         reinterpret_cast<uint32_t>(
-             isolate->builtins()->OsrAfterStackCheck()->entry()));
-  return OSR_AFTER_STACK_CHECK;
+  *stack_depth = 0;
+  *context_length = 0;
+  return previous_;
 }
 
 
+#undef __
+
+
 } }  // namespace v8::internal
 
-#endif  // V8_TARGET_ARCH_ARM
+#endif  // V8_TARGET_ARCH_A64