Enable stub generation using Hydrogen/Lithium (again)

src/ia32/lithium-codegen-ia32.cc

 // Copyright 2012 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
@@ skipping 12 matching lines @@
 // 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 defined(V8_TARGET_ARCH_IA32)
 
 #include "ia32/lithium-codegen-ia32.h"
+#include "ic.h"
 #include "code-stubs.h"
 #include "deoptimizer.h"
 #include "stub-cache.h"
 #include "codegen.h"
 
 namespace v8 {
 namespace internal {
 
 
 // When invoking builtins, we need to record the safepoint in the middle of
@@ skipping 20 matching lines @@
   Safepoint::DeoptMode deopt_mode_;
 };
 
 
 #define __ masm()->
 
 bool LCodeGen::GenerateCode() {
   HPhase phase("Z_Code generation", chunk());
   ASSERT(is_unused());
   status_ = GENERATING;
-  CpuFeatures::Scope scope(SSE2);
 
   CodeStub::GenerateFPStubs();
 
   // 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 in GeneratePrologue).
   FrameScope frame_scope(masm_, StackFrame::MANUAL);
 
-  dynamic_frame_alignment_ = (chunk()->num_double_slots() > 2 &&
-                              !chunk()->graph()->is_recursive()) ||
-                             !info()->osr_ast_id().IsNone();
+  dynamic_frame_alignment_ = info()->IsOptimizing() &&
+      ((chunk()->num_double_slots() > 2 &&
+        !chunk()->graph()->is_recursive()) ||
+       !info()->osr_ast_id().IsNone());
 
   return GeneratePrologue() &&
       GenerateBody() &&
       GenerateDeferredCode() &&
       GenerateSafepointTable();
 }
 
 
 void LCodeGen::FinishCode(Handle<Code> code) {
   ASSERT(is_done());
   code->set_stack_slots(GetStackSlotCount());
   code->set_safepoint_table_offset(safepoints_.GetCodeOffset());
   PopulateDeoptimizationData(code);
-  Deoptimizer::EnsureRelocSpaceForLazyDeoptimization(code);
+  if (!info()->IsStub()) {
+    Deoptimizer::EnsureRelocSpaceForLazyDeoptimization(code);
+  }
 }
 
 
 void LCodeGen::Abort(const char* reason) {
   info()->set_bailout_reason(reason);
   status_ = ABORTED;
 }
 
 
 void LCodeGen::Comment(const char* format, ...) {
@@ skipping 10 matching lines @@
   size_t length = builder.position();
   Vector<char> copy = Vector<char>::New(length + 1);
   memcpy(copy.start(), builder.Finalize(), copy.length());
   masm()->RecordComment(copy.start());
 }
 
 
 bool LCodeGen::GeneratePrologue() {
   ASSERT(is_generating());
 
-  ProfileEntryHookStub::MaybeCallEntryHook(masm_);
+  if (info()->IsOptimizing()) {
+    ProfileEntryHookStub::MaybeCallEntryHook(masm_);
 
 #ifdef DEBUG
-  if (strlen(FLAG_stop_at) > 0 &&
-      info_->function()->name()->IsEqualTo(CStrVector(FLAG_stop_at))) {
-    __ int3();
-  }
+    if (strlen(FLAG_stop_at) > 0 &&
+        info_->function()->name()->IsEqualTo(CStrVector(FLAG_stop_at))) {
+      __ int3();
+    }
 #endif
 
-  // Strict mode functions and builtins need to replace the receiver
-  // with undefined when called as functions (without an explicit
-  // receiver object). ecx is zero for method calls and non-zero for
-  // function calls.
-  if (!info_->is_classic_mode() || info_->is_native()) {
-    Label begin;
-    __ bind(&begin);
-    Label ok;
-    __ test(ecx, Operand(ecx));
-    __ j(zero, &ok, Label::kNear);
-    // +1 for return address.
-    int receiver_offset = (scope()->num_parameters() + 1) * kPointerSize;
-    __ mov(Operand(esp, receiver_offset),
-           Immediate(isolate()->factory()->undefined_value()));
-    __ bind(&ok);
-    ASSERT(!FLAG_age_code ||
-           (kSizeOfOptimizedStrictModePrologue == ok.pos() - begin.pos()));
+    // Strict mode functions and builtins need to replace the receiver
+    // with undefined when called as functions (without an explicit
+    // receiver object). ecx is zero for method calls and non-zero for
+    // function calls.
+    if (!info_->is_classic_mode() || info_->is_native()) {
+      Label begin;
+      __ bind(&begin);
+      Label ok;
+      __ test(ecx, Operand(ecx));
+      __ j(zero, &ok, Label::kNear);
+      // +1 for return address.
+      int receiver_offset = (scope()->num_parameters() + 1) * kPointerSize;
+      __ mov(Operand(esp, receiver_offset),
+             Immediate(isolate()->factory()->undefined_value()));
+      __ bind(&ok);
+      ASSERT(!FLAG_age_code ||
+             (kSizeOfOptimizedStrictModePrologue == ok.pos() - begin.pos()));
+    }
   }
 
-
   if (dynamic_frame_alignment_) {
     Label begin;
     __ bind(&begin);
     // Move state of dynamic frame alignment into edx.
     __ mov(edx, Immediate(kNoAlignmentPadding));
 
     Label do_not_pad, align_loop;
     STATIC_ASSERT(kDoubleSize == 2 * kPointerSize);
     // Align esp + 4 to a multiple of 2 * kPointerSize.
     __ test(esp, Immediate(kPointerSize));
@@ skipping 10 matching lines @@
     __ add(Operand(ebx), Immediate(kPointerSize));
     __ dec(ecx);
     __ j(not_zero, &align_loop, Label::kNear);
     __ mov(Operand(ebx, 0), Immediate(kAlignmentZapValue));
     __ bind(&do_not_pad);
     ASSERT(!FLAG_age_code ||
            (kSizeOfOptimizedAlignStackPrologue ==
             do_not_pad.pos() - begin.pos()));
   }
 
-  __ push(ebp);  // Caller's frame pointer.
-  __ mov(ebp, esp);
-  __ push(esi);  // Callee's context.
-  __ push(edi);  // Callee's JS function.
+  if (NeedsEagerFrame()) {
+    ASSERT(!frame_is_built_);
+    frame_is_built_ = true;
+    __ push(ebp);  // Caller's frame pointer.
+    __ mov(ebp, esp);
+    if (info()->IsStub()) {
+      __ push(esi);
+      __ push(Immediate(Smi::FromInt(StackFrame::STUB)));
+    } else {
+      __ push(esi);  // Callee's context.
+      __ push(edi);  // Callee's JS function.
+    }
+  }
 
   if (dynamic_frame_alignment_ && FLAG_debug_code) {
     __ test(esp, Immediate(kPointerSize));
     __ Assert(zero, "frame is expected to be aligned");
   }
 
   // Reserve space for the stack slots needed by the code.
   int slots = GetStackSlotCount();
-  ASSERT_GE(slots, 1);
-  if (slots == 1) {
-    if (dynamic_frame_alignment_) {
-      __ push(edx);
+  ASSERT(slots != 0 || !info()->IsOptimizing());
+  if (slots > 0) {
+    if (slots == 1) {
+      if (dynamic_frame_alignment_) {
+        __ push(edx);
+      } else {
+        __ push(Immediate(kNoAlignmentPadding));
+      }
     } else {
-      __ push(Immediate(kNoAlignmentPadding));
-    }
-  } else {
-    if (FLAG_debug_code) {
-      __ mov(Operand(eax), Immediate(slots));
-      Label loop;
-      __ bind(&loop);
-      __ push(Immediate(kSlotsZapValue));
-      __ dec(eax);
-      __ j(not_zero, &loop);
-    } else {
-      __ sub(Operand(esp), Immediate(slots * kPointerSize));
-  #ifdef _MSC_VER
-      // On windows, you may not access the stack more than one page below
-      // the most recently mapped page. To make the allocated area randomly
-      // accessible, we write to each page in turn (the value is irrelevant).
-      const int kPageSize = 4 * KB;
-      for (int offset = slots * kPointerSize - kPageSize;
-           offset > 0;
-           offset -= kPageSize) {
-        __ mov(Operand(esp, offset), eax);
+      if (FLAG_debug_code) {
+        __ mov(Operand(eax), Immediate(slots));
+        Label loop;
+        __ bind(&loop);
+        __ push(Immediate(kSlotsZapValue));
+        __ dec(eax);
+        __ j(not_zero, &loop);
+      } else {
+        __ sub(Operand(esp), Immediate(slots * kPointerSize));
+#ifdef _MSC_VER
+        // On windows, you may not access the stack more than one page below
+        // the most recently mapped page. To make the allocated area randomly
+        // accessible, we write to each page in turn (the value is irrelevant).
+        const int kPageSize = 4 * KB;
+        for (int offset = slots * kPointerSize - kPageSize;
+             offset > 0;
+             offset -= kPageSize) {
+          __ mov(Operand(esp, offset), eax);
+        }
+#endif
       }
-  #endif
-    }
 
-    // Store dynamic frame alignment state in the first local.
-    if (dynamic_frame_alignment_) {
-      __ mov(Operand(ebp,
-                     JavaScriptFrameConstants::kDynamicAlignmentStateOffset),
-             edx);
-    } else {
-      __ mov(Operand(ebp,
-                     JavaScriptFrameConstants::kDynamicAlignmentStateOffset),
-             Immediate(kNoAlignmentPadding));
+      // Store dynamic frame alignment state in the first local.
+      if (dynamic_frame_alignment_) {
+        __ mov(Operand(ebp,
+                       JavaScriptFrameConstants::kDynamicAlignmentStateOffset),
+               edx);
+      } else {
+        __ mov(Operand(ebp,
+                       JavaScriptFrameConstants::kDynamicAlignmentStateOffset),
+               Immediate(kNoAlignmentPadding));
+      }
     }
   }
 
   // Possibly allocate a local context.
-  int heap_slots = scope()->num_heap_slots() - Context::MIN_CONTEXT_SLOTS;
+  int heap_slots = info_->num_heap_slots() - Context::MIN_CONTEXT_SLOTS;
   if (heap_slots > 0) {
     Comment(";;; Allocate local context");
     // Argument to NewContext is the function, which is still in edi.
     __ push(edi);
     if (heap_slots <= FastNewContextStub::kMaximumSlots) {
       FastNewContextStub stub(heap_slots);
       __ CallStub(&stub);
     } else {
       __ CallRuntime(Runtime::kNewFunctionContext, 1);
     }
@@ skipping 19 matching lines @@
                                   context_offset,
                                   eax,
                                   ebx,
                                   kDontSaveFPRegs);
       }
     }
     Comment(";;; End allocate local context");
   }
 
   // Trace the call.
-  if (FLAG_trace) {
+  if (FLAG_trace && info()->IsOptimizing()) {
     // We have not executed any compiled code yet, so esi still holds the
     // incoming context.
     __ CallRuntime(Runtime::kTraceEnter, 0);
   }
   return !is_aborted();
 }
 
 
 bool LCodeGen::GenerateBody() {
   ASSERT(is_generating());
@@ skipping 12 matching lines @@
       instr->CompileToNative(this);
     }
   }
   EnsureSpaceForLazyDeopt();
   return !is_aborted();
 }
 
 
 bool LCodeGen::GenerateDeferredCode() {
   ASSERT(is_generating());
+
   if (deferred_.length() > 0) {
     for (int i = 0; !is_aborted() && i < deferred_.length(); i++) {
       LDeferredCode* code = deferred_[i];
       __ bind(code->entry());
+      if (NeedsDeferredFrame()) {
+        Comment(";;; Deferred build frame",
+                code->instruction_index(),
+                code->instr()->Mnemonic());
+        ASSERT(!frame_is_built_);
+        ASSERT(info()->IsStub());
+        frame_is_built_ = true;
+        // Build the frame in such a way that esi isn't trashed.
+        __ push(ebp);  // Caller's frame pointer.
+        __ push(Operand(ebp, StandardFrameConstants::kContextOffset));
+        __ push(Immediate(Smi::FromInt(StackFrame::STUB)));
+        __ lea(ebp, Operand(esp, 2 * kPointerSize));
+      }
       Comment(";;; Deferred code @%d: %s.",
               code->instruction_index(),
               code->instr()->Mnemonic());
       code->Generate();
+      if (NeedsDeferredFrame()) {
+        Comment(";;; Deferred destory frame",
+                code->instruction_index(),
+                code->instr()->Mnemonic());
+        ASSERT(frame_is_built_);
+        frame_is_built_ = false;
+        __ mov(esp, ebp);
+        __ pop(ebp);
+      }
       __ jmp(code->exit());
     }
   }
 
   // Deferred code is the last part of the instruction sequence. Mark
   // the generated code as done unless we bailed out.
   if (!is_aborted()) status_ = DONE;
   return !is_aborted();
 }
 
 
 bool LCodeGen::GenerateSafepointTable() {
   ASSERT(is_done());
+  if (!info()->IsStub()) {
+    // For lazy deoptimization we need space to patch a call after every call.
+    // Ensure there is always space for such patching, even if the code ends
+    // in a call.
+    int target_offset = masm()->pc_offset() + Deoptimizer::patch_size();
+    while (masm()->pc_offset() < target_offset) {
+      masm()->nop();
+    }
+  }
   safepoints_.Emit(masm(), GetStackSlotCount());
   return !is_aborted();
 }
 
 
 Register LCodeGen::ToRegister(int index) const {
   return Register::FromAllocationIndex(index);
 }
 
 
 XMMRegister LCodeGen::ToDoubleRegister(int index) const {
   return XMMRegister::FromAllocationIndex(index);
 }
 
 
+bool LCodeGen::IsX87TopOfStack(LOperand* op) const {
+  return op->IsDoubleRegister();
+}
+
+
 Register LCodeGen::ToRegister(LOperand* op) const {
   ASSERT(op->IsRegister());
   return ToRegister(op->index());
 }
 
 
 XMMRegister LCodeGen::ToDoubleRegister(LOperand* op) const {
   ASSERT(op->IsDoubleRegister());
   return ToDoubleRegister(op->index());
 }
@@ skipping 65 matching lines @@
   // arguments index points to the first element of a sequence of tagged
   // values on the stack that represent the arguments. This needs to be
   // kept in sync with the LArgumentsElements implementation.
   *arguments_index = -environment->parameter_count();
   *arguments_count = environment->parameter_count();
 
   WriteTranslation(environment->outer(),
                    translation,
                    arguments_index,
                    arguments_count);
-  int closure_id = *info()->closure() != *environment->closure()
+  bool has_closure_id = !info()->closure().is_null() &&
+      *info()->closure() != *environment->closure();
+  int closure_id = has_closure_id
       ? DefineDeoptimizationLiteral(environment->closure())
       : Translation::kSelfLiteralId;
   switch (environment->frame_type()) {
     case JS_FUNCTION:
       translation->BeginJSFrame(environment->ast_id(), closure_id, height);
       break;
     case JS_CONSTRUCT:
       translation->BeginConstructStubFrame(closure_id, translation_size);
       break;
     case JS_GETTER:
       ASSERT(translation_size == 1);
       ASSERT(height == 0);
       translation->BeginGetterStubFrame(closure_id);
       break;
     case JS_SETTER:
       ASSERT(translation_size == 2);
       ASSERT(height == 0);
       translation->BeginSetterStubFrame(closure_id);
       break;
     case ARGUMENTS_ADAPTOR:
       translation->BeginArgumentsAdaptorFrame(closure_id, translation_size);
       break;
+    case STUB:
+      translation->BeginCompiledStubPseudoFrame(Code::KEYED_LOAD_IC);
+      break;
+    default:
+      UNREACHABLE();
   }
 
   // Inlined frames which push their arguments cause the index to be
   // bumped and another stack area to be used for materialization.
   if (environment->entry() != NULL &&
       environment->entry()->arguments_pushed()) {
     *arguments_index = *arguments_index < 0
         ? GetStackSlotCount()
         : *arguments_index + *arguments_count;
     *arguments_count = environment->entry()->arguments_count() + 1;
@@ skipping 114 matching lines @@
                            int argc,
                            LInstruction* instr) {
   ASSERT(instr != NULL);
   ASSERT(instr->HasPointerMap());
   LPointerMap* pointers = instr->pointer_map();
   RecordPosition(pointers->position());
 
   __ CallRuntime(fun, argc);
 
   RecordSafepointWithLazyDeopt(instr, RECORD_SIMPLE_SAFEPOINT);
+
+  ASSERT(info()->is_calling());
 }
 
 
 void LCodeGen::CallRuntimeFromDeferred(Runtime::FunctionId id,
                                        int argc,
                                        LInstruction* instr,
                                        LOperand* context) {
   if (context->IsRegister()) {
     if (!ToRegister(context).is(esi)) {
       __ mov(esi, ToRegister(context));
     }
   } else if (context->IsStackSlot()) {
     __ mov(esi, ToOperand(context));
   } else if (context->IsConstantOperand()) {
     HConstant* constant =
         chunk_->LookupConstant(LConstantOperand::cast(context));
     __ LoadHeapObject(esi, Handle<Context>::cast(constant->handle()));
   } else {
     UNREACHABLE();
   }
 
   __ CallRuntimeSaveDoubles(id);
   RecordSafepointWithRegisters(
       instr->pointer_map(), argc, Safepoint::kNoLazyDeopt);
+
+  ASSERT(info()->is_calling());
 }
 
 
 void LCodeGen::RegisterEnvironmentForDeoptimization(
     LEnvironment* environment, Safepoint::DeoptMode mode) {
   if (!environment->HasBeenRegistered()) {
     // Physical stack frame layout:
     // -x ............. -4  0 ..................................... y
     // [incoming arguments] [spill slots] [pushed outgoing arguments]
 
@@ skipping 25 matching lines @@
                           (mode == Safepoint::kLazyDeopt) ? pc_offset : -1);
     deoptimizations_.Add(environment, zone());
   }
 }
 
 
 void LCodeGen::DeoptimizeIf(Condition cc, LEnvironment* environment) {
   RegisterEnvironmentForDeoptimization(environment, Safepoint::kNoLazyDeopt);
   ASSERT(environment->HasBeenRegistered());
   int id = environment->deoptimization_index();
-  Address entry = Deoptimizer::GetDeoptimizationEntry(id, Deoptimizer::EAGER);
+  ASSERT(info()->IsOptimizing() || info()->IsStub());
+  Deoptimizer::BailoutType bailout_type = frame_is_built_
+      ? Deoptimizer::EAGER
+      : Deoptimizer::LAZY;
+  Address entry = Deoptimizer::GetDeoptimizationEntry(id, bailout_type);
   if (entry == NULL) {
     Abort("bailout was not prepared");
     return;
   }
 
   if (FLAG_deopt_every_n_times != 0) {
     Handle<SharedFunctionInfo> shared(info_->shared_info());
     Label no_deopt;
     __ pushfd();
     __ push(eax);
@@ skipping 13 matching lines @@
     __ jmp(entry, RelocInfo::RUNTIME_ENTRY);
 
     __ bind(&no_deopt);
     __ mov(FieldOperand(ebx, SharedFunctionInfo::kStressDeoptCounterOffset),
            eax);
     __ pop(ebx);
     __ pop(eax);
     __ popfd();
   }
 
+  ASSERT(info()->IsStub() || frame_is_built_);
   if (cc == no_condition) {
     if (FLAG_trap_on_deopt) __ int3();
-    __ jmp(entry, RelocInfo::RUNTIME_ENTRY);
+    if (frame_is_built_) {
+      __ jmp(entry, RelocInfo::RUNTIME_ENTRY);
+    } else {
+      __ call(entry, RelocInfo::RUNTIME_ENTRY);
+    }
   } else {
     if (FLAG_trap_on_deopt) {
       Label done;
       __ j(NegateCondition(cc), &done, Label::kNear);
       __ int3();
-      __ jmp(entry, RelocInfo::RUNTIME_ENTRY);
+      if (frame_is_built_) {
+        __ jmp(entry, RelocInfo::RUNTIME_ENTRY);
+      } else {
+        __ call(entry, RelocInfo::RUNTIME_ENTRY);
+      }
       __ bind(&done);
     } else {
-      __ j(cc, entry, RelocInfo::RUNTIME_ENTRY);
+      if (frame_is_built_) {
+        __ j(cc, entry, RelocInfo::RUNTIME_ENTRY);
+      } else {
+        Label done;
+        __ j(NegateCondition(cc), &done, Label::kNear);
+        __ call(entry, RelocInfo::RUNTIME_ENTRY);
+        __ bind(&done);
+      }
     }
   }
 }
 
 
 void LCodeGen::PopulateDeoptimizationData(Handle<Code> code) {
   int length = deoptimizations_.length();
   if (length == 0) return;
   Handle<DeoptimizationInputData> data =
       factory()->NewDeoptimizationInputData(length, TENURED);
@@ skipping 681 matching lines @@
   // Use xor to produce +0.0 in a fast and compact way, but avoid to
   // do so if the constant is -0.0.
   if (BitCast<uint64_t, double>(v) == 0) {
     __ xorps(res, res);
   } else {
     Register temp = ToRegister(instr->temp());
     uint64_t int_val = BitCast<uint64_t, double>(v);
     int32_t lower = static_cast<int32_t>(int_val);
     int32_t upper = static_cast<int32_t>(int_val >> (kBitsPerInt));
     if (CpuFeatures::IsSupported(SSE4_1)) {
-      CpuFeatures::Scope scope(SSE4_1);
+      CpuFeatures::Scope scope1(SSE2);
+      CpuFeatures::Scope scope2(SSE4_1);
       if (lower != 0) {
         __ Set(temp, Immediate(lower));
         __ movd(res, Operand(temp));
         __ Set(temp, Immediate(upper));
         __ pinsrd(res, Operand(temp), 1);
       } else {
         __ xorps(res, res);
         __ Set(temp, Immediate(upper));
         __ pinsrd(res, Operand(temp), 1);
       }
     } else {
+      ASSERT(CpuFeatures::IsSupported(SSE2));
+      CpuFeatures::Scope scope(SSE2);
       __ Set(temp, Immediate(upper));
       __ movd(res, Operand(temp));
       __ psllq(res, 32);
       if (lower != 0) {
         __ Set(temp, Immediate(lower));
         __ movd(xmm0, Operand(temp));
         __ por(res, xmm0);
       }
     }
   }
@@ skipping 133 matching lines @@
     __ add(ToRegister(left), ToOperand(right));
   }
 
   if (instr->hydrogen()->CheckFlag(HValue::kCanOverflow)) {
     DeoptimizeIf(overflow, instr->environment());
   }
 }
 
 
 void LCodeGen::DoMathMinMax(LMathMinMax* instr) {
+  CpuFeatures::Scope scope(SSE2);
   LOperand* left = instr->left();
   LOperand* right = instr->right();
   ASSERT(left->Equals(instr->result()));
   HMathMinMax::Operation operation = instr->hydrogen()->operation();
   if (instr->hydrogen()->representation().IsInteger32()) {
     Label return_left;
     Condition condition = (operation == HMathMinMax::kMathMin)
         ? less_equal
         : greater_equal;
     if (right->IsConstantOperand()) {
@@ skipping 41 matching lines @@
     __ j(parity_even, &return_left, Label::kNear);  // left == NaN.
     __ bind(&return_right);
     __ movsd(left_reg, right_reg);
 
     __ bind(&return_left);
   }
 }
 
 
 void LCodeGen::DoArithmeticD(LArithmeticD* instr) {
+  ASSERT(CpuFeatures::IsSupported(SSE2));
+  CpuFeatures::Scope scope(SSE2);
   XMMRegister left = ToDoubleRegister(instr->left());
   XMMRegister right = ToDoubleRegister(instr->right());
   XMMRegister result = ToDoubleRegister(instr->result());
   // Modulo uses a fixed result register.
   ASSERT(instr->op() == Token::MOD || left.is(result));
   switch (instr->op()) {
     case Token::ADD:
       __ addsd(left, right);
       break;
     case Token::SUB:
-       __ subsd(left, right);
-       break;
+      __ subsd(left, right);
+      break;
     case Token::MUL:
       __ mulsd(left, right);
       break;
     case Token::DIV:
       __ divsd(left, right);
       break;
     case Token::MOD: {
       // Pass two doubles as arguments on the stack.
       __ PrepareCallCFunction(4, eax);
       __ movdbl(Operand(esp, 0 * kDoubleSize), left);
@@ skipping 52 matching lines @@
   } else {
     __ j(cc, chunk_->GetAssemblyLabel(left_block));
     __ jmp(chunk_->GetAssemblyLabel(right_block));
   }
 }
 
 
 void LCodeGen::DoBranch(LBranch* instr) {
   int true_block = chunk_->LookupDestination(instr->true_block_id());
   int false_block = chunk_->LookupDestination(instr->false_block_id());
+  CpuFeatures::Scope scope(SSE2);
 
   Representation r = instr->hydrogen()->value()->representation();
   if (r.IsInteger32()) {
     Register reg = ToRegister(instr->value());
     __ test(reg, Operand(reg));
     EmitBranch(true_block, false_block, not_zero);
   } else if (r.IsDouble()) {
     XMMRegister reg = ToDoubleRegister(instr->value());
     __ xorps(xmm0, xmm0);
     __ ucomisd(reg, xmm0);
@@ skipping 139 matching lines @@
   return cond;
 }
 
 
 void LCodeGen::DoCmpIDAndBranch(LCmpIDAndBranch* instr) {
   LOperand* left = instr->left();
   LOperand* right = instr->right();
   int false_block = chunk_->LookupDestination(instr->false_block_id());
   int true_block = chunk_->LookupDestination(instr->true_block_id());
   Condition cc = TokenToCondition(instr->op(), instr->is_double());
+  CpuFeatures::Scope scope(SSE2);
 
   if (left->IsConstantOperand() && right->IsConstantOperand()) {
     // We can statically evaluate the comparison.
     double left_val = ToDouble(LConstantOperand::cast(left));
     double right_val = ToDouble(LConstantOperand::cast(right));
     int next_block =
       EvalComparison(instr->op(), left_val, right_val) ? true_block
                                                        : false_block;
     EmitGoto(next_block);
   } else {
@@ skipping 489 matching lines @@
   __ j(condition, &true_value, Label::kNear);
   __ mov(ToRegister(instr->result()), factory()->false_value());
   __ jmp(&done, Label::kNear);
   __ bind(&true_value);
   __ mov(ToRegister(instr->result()), factory()->true_value());
   __ bind(&done);
 }
 
 
 void LCodeGen::DoReturn(LReturn* instr) {
-  if (FLAG_trace) {
+  if (FLAG_trace && info()->IsOptimizing()) {
     // Preserve the return value on the stack and rely on the runtime call
     // to return the value in the same register.  We're leaving the code
     // managed by the register allocator and tearing down the frame, it's
     // safe to write to the context register.
     __ push(eax);
     __ mov(esi, Operand(ebp, StandardFrameConstants::kContextOffset));
     __ CallRuntime(Runtime::kTraceExit, 1);
   }
   if (dynamic_frame_alignment_) {
     // Fetch the state of the dynamic frame alignment.
     __ mov(edx, Operand(ebp,
       JavaScriptFrameConstants::kDynamicAlignmentStateOffset));
   }
-  __ mov(esp, ebp);
-  __ pop(ebp);
+  if (NeedsEagerFrame()) {
+    __ mov(esp, ebp);
+    __ pop(ebp);
+  }
   if (dynamic_frame_alignment_) {
     Label no_padding;
     __ cmp(edx, Immediate(kNoAlignmentPadding));
     __ j(equal, &no_padding);
     if (FLAG_debug_code) {
       __ cmp(Operand(esp, (GetParameterCount() + 2) * kPointerSize),
              Immediate(kAlignmentZapValue));
       __ Assert(equal, "expected alignment marker");
     }
     __ Ret((GetParameterCount() + 2) * kPointerSize, ecx);
     __ bind(&no_padding);
   }
-  __ Ret((GetParameterCount() + 1) * kPointerSize, ecx);
+  if (info()->IsStub()) {
+    __ mov(esi, Operand(ebp, StandardFrameConstants::kContextOffset));
+    __ Ret();
+  } else {
+    __ Ret((GetParameterCount() + 1) * kPointerSize, ecx);
+  }
 }
 
 
 void LCodeGen::DoLoadGlobalCell(LLoadGlobalCell* instr) {
   Register result = ToRegister(instr->result());
   __ mov(result, Operand::Cell(instr->hydrogen()->cell()));
   if (instr->hydrogen()->RequiresHoleCheck()) {
     __ cmp(result, factory()->the_hole_value());
     DeoptimizeIf(equal, instr->environment());
   }
@@ skipping 355 matching lines @@
     __ SmiUntag(ToRegister(key));
   }
   Operand operand(BuildFastArrayOperand(
       instr->elements(),
       key,
       instr->hydrogen()->key()->representation(),
       elements_kind,
       0,
       instr->additional_index()));
   if (elements_kind == EXTERNAL_FLOAT_ELEMENTS) {
-    XMMRegister result(ToDoubleRegister(instr->result()));
-    __ movss(result, operand);
-    __ cvtss2sd(result, result);
+    if (CpuFeatures::IsSupported(SSE2)) {
+      CpuFeatures::Scope scope(SSE2);
+      XMMRegister result(ToDoubleRegister(instr->result()));
+      __ movss(result, operand);
+      __ cvtss2sd(result, result);
+    } else {
+      __ fld_s(operand);
+      HandleX87FPReturnValue(instr);
+    }
   } else if (elements_kind == EXTERNAL_DOUBLE_ELEMENTS) {
-    __ movdbl(ToDoubleRegister(instr->result()), operand);
+    if (CpuFeatures::IsSupported(SSE2)) {
+      CpuFeatures::Scope scope(SSE2);
+      __ movdbl(ToDoubleRegister(instr->result()), operand);
+    } else {
+      __ fld_d(operand);
+      HandleX87FPReturnValue(instr);
+    }
   } else {
     Register result(ToRegister(instr->result()));
     switch (elements_kind) {
       case EXTERNAL_BYTE_ELEMENTS:
         __ movsx_b(result, operand);
         break;
       case EXTERNAL_PIXEL_ELEMENTS:
       case EXTERNAL_UNSIGNED_BYTE_ELEMENTS:
         __ movzx_b(result, operand);
         break;
@@ skipping 23 matching lines @@
       case FAST_HOLEY_DOUBLE_ELEMENTS:
       case DICTIONARY_ELEMENTS:
       case NON_STRICT_ARGUMENTS_ELEMENTS:
         UNREACHABLE();
         break;
     }
   }
 }
 
 
+void LCodeGen::HandleX87FPReturnValue(LInstruction* instr) {
+  if (IsX87TopOfStack(instr->result())) {
+    // Return value is already on stack. If the value has no uses, then
+    // pop it off the FP stack. Otherwise, make sure that there are enough
+    // copies of the value on the stack to feed all of the usages, e.g.
+    // when the following instruction uses the return value in multiple
+    // inputs.
+    int count = instr->hydrogen_value()->UseCount();
+    if (count == 0) {
+      __ fstp(0);
+    } else {
+      count--;
+      ASSERT(count <= 7);
+      while (count-- > 0) {
+        __ fld(0);
+      }
+    }
+  } else {
+    __ fstp_d(ToOperand(instr->result()));
+  }
+}
+
+
 void LCodeGen::DoLoadKeyedFixedDoubleArray(LLoadKeyed* instr) {
-  XMMRegister result = ToDoubleRegister(instr->result());
-
   if (instr->hydrogen()->RequiresHoleCheck()) {
     int offset = FixedDoubleArray::kHeaderSize - kHeapObjectTag +
         sizeof(kHoleNanLower32);
     Operand hole_check_operand = BuildFastArrayOperand(
         instr->elements(), instr->key(),
         instr->hydrogen()->key()->representation(),
         FAST_DOUBLE_ELEMENTS,
         offset,
         instr->additional_index());
     __ cmp(hole_check_operand, Immediate(kHoleNanUpper32));
     DeoptimizeIf(equal, instr->environment());
   }
 
   Operand double_load_operand = BuildFastArrayOperand(
       instr->elements(),
       instr->key(),
       instr->hydrogen()->key()->representation(),
       FAST_DOUBLE_ELEMENTS,
       FixedDoubleArray::kHeaderSize - kHeapObjectTag,
       instr->additional_index());
-  __ movdbl(result, double_load_operand);
+  if (CpuFeatures::IsSupported(SSE2)) {
+    CpuFeatures::Scope scope(SSE2);
+    XMMRegister result = ToDoubleRegister(instr->result());
+    __ movdbl(result, double_load_operand);
+  } else {
+    __ fld_d(double_load_operand);
+    HandleX87FPReturnValue(instr);
+  }
 }
 
 
 void LCodeGen::DoLoadKeyedFixedArray(LLoadKeyed* instr) {
   Register result = ToRegister(instr->result());
 
   // Load the result.
   __ mov(result,
          BuildFastArrayOperand(instr->elements(),
                                instr->key(),
@@ skipping 395 matching lines @@
       codegen()->DoDeferredMathAbsTaggedHeapNumber(instr_);
     }
     virtual LInstruction* instr() { return instr_; }
    private:
     LUnaryMathOperation* instr_;
   };
 
   ASSERT(instr->value()->Equals(instr->result()));
   Representation r = instr->hydrogen()->value()->representation();
 
+  CpuFeatures::Scope scope(SSE2);
   if (r.IsDouble()) {
     XMMRegister  scratch = xmm0;
     XMMRegister input_reg = ToDoubleRegister(instr->value());
     __ xorps(scratch, scratch);
     __ subsd(scratch, input_reg);
     __ pand(input_reg, scratch);
   } else if (r.IsInteger32()) {
     EmitIntegerMathAbs(instr);
   } else {  // Tagged case.
     DeferredMathAbsTaggedHeapNumber* deferred =
         new(zone()) DeferredMathAbsTaggedHeapNumber(this, instr);
     Register input_reg = ToRegister(instr->value());
     // Smi check.
     __ JumpIfNotSmi(input_reg, deferred->entry());
     EmitIntegerMathAbs(instr);
     __ bind(deferred->exit());
   }
 }
 
 
 void LCodeGen::DoMathFloor(LUnaryMathOperation* instr) {
+  CpuFeatures::Scope scope(SSE2);
   XMMRegister xmm_scratch = xmm0;
   Register output_reg = ToRegister(instr->result());
   XMMRegister input_reg = ToDoubleRegister(instr->value());
 
   if (CpuFeatures::IsSupported(SSE4_1)) {
     CpuFeatures::Scope scope(SSE4_1);
     if (instr->hydrogen()->CheckFlag(HValue::kBailoutOnMinusZero)) {
       // Deoptimize on negative zero.
       Label non_zero;
       __ xorps(xmm_scratch, xmm_scratch);  // Zero the register.
@@ skipping 44 matching lines @@
     __ ucomisd(input_reg, xmm_scratch);
     __ j(equal, &done, Label::kNear);
     __ sub(output_reg, Immediate(1));
     DeoptimizeIf(overflow, instr->environment());
 
     __ bind(&done);
   }
 }
 
 void LCodeGen::DoMathRound(LUnaryMathOperation* instr) {
+  CpuFeatures::Scope scope(SSE2);
   XMMRegister xmm_scratch = xmm0;
   Register output_reg = ToRegister(instr->result());
   XMMRegister input_reg = ToDoubleRegister(instr->value());
 
   Label below_half, done;
   // xmm_scratch = 0.5
   ExternalReference one_half = ExternalReference::address_of_one_half();
   __ movdbl(xmm_scratch, Operand::StaticVariable(one_half));
   __ ucomisd(xmm_scratch, input_reg);
   __ j(above, &below_half);
@@ skipping 25 matching lines @@
     __ cvtss2sd(xmm_scratch, xmm_scratch);
     __ ucomisd(input_reg, xmm_scratch);
     DeoptimizeIf(below, instr->environment());
   }
   __ Set(output_reg, Immediate(0));
   __ bind(&done);
 }
 
 
 void LCodeGen::DoMathSqrt(LUnaryMathOperation* instr) {
+  CpuFeatures::Scope scope(SSE2);
   XMMRegister input_reg = ToDoubleRegister(instr->value());
   ASSERT(ToDoubleRegister(instr->result()).is(input_reg));
   __ sqrtsd(input_reg, input_reg);
 }
 
 
 void LCodeGen::DoMathPowHalf(LMathPowHalf* instr) {
+  CpuFeatures::Scope scope(SSE2);
   XMMRegister xmm_scratch = xmm0;
   XMMRegister input_reg = ToDoubleRegister(instr->value());
   Register scratch = ToRegister(instr->temp());
   ASSERT(ToDoubleRegister(instr->result()).is(input_reg));
 
   // Note that according to ECMA-262 15.8.2.13:
   // Math.pow(-Infinity, 0.5) == Infinity
   // Math.sqrt(-Infinity) == NaN
   Label done, sqrt;
   // Check base for -Infinity.  According to IEEE-754, single-precision
@@ skipping 56 matching lines @@
     DeferredDoRandom(LCodeGen* codegen, LRandom* instr)
         : LDeferredCode(codegen), instr_(instr) { }
     virtual void Generate() { codegen()->DoDeferredRandom(instr_); }
     virtual LInstruction* instr() { return instr_; }
    private:
     LRandom* instr_;
   };
 
   DeferredDoRandom* deferred = new(zone()) DeferredDoRandom(this, instr);
 
+  CpuFeatures::Scope scope(SSE2);
   // Having marked this instruction as a call we can use any
   // registers.
   ASSERT(ToDoubleRegister(instr->result()).is(xmm1));
   ASSERT(ToRegister(instr->global_object()).is(eax));
   // Assert that the register size is indeed the size of each seed.
   static const int kSeedSize = sizeof(uint32_t);
   STATIC_ASSERT(kPointerSize == kSeedSize);
 
   __ mov(eax, FieldOperand(eax, GlobalObject::kNativeContextOffset));
   static const int kRandomSeedOffset =
@@ skipping 47 matching lines @@
 
 void LCodeGen::DoDeferredRandom(LRandom* instr) {
   __ PrepareCallCFunction(1, ebx);
   __ mov(Operand(esp, 0), eax);
   __ CallCFunction(ExternalReference::random_uint32_function(isolate()), 1);
   // Return value is in eax.
 }
 
 
 void LCodeGen::DoMathLog(LUnaryMathOperation* instr) {
+  CpuFeatures::Scope scope(SSE2);
   ASSERT(instr->value()->Equals(instr->result()));
   XMMRegister input_reg = ToDoubleRegister(instr->value());
   Label positive, done, zero;
   __ xorps(xmm0, xmm0);
   __ ucomisd(input_reg, xmm0);
   __ j(above, &positive, Label::kNear);
   __ j(equal, &zero, Label::kNear);
   ExternalReference nan =
       ExternalReference::address_of_canonical_non_hole_nan();
   __ movdbl(input_reg, Operand::StaticVariable(nan));
@@ skipping 269 matching lines @@
     int constant_index =
         ToInteger32(LConstantOperand::cast(instr->index()));
     if (instr->hydrogen()->length()->representation().IsTagged()) {
       __ cmp(ToOperand(instr->length()),
              Immediate(Smi::FromInt(constant_index)));
     } else {
       __ cmp(ToOperand(instr->length()), Immediate(constant_index));
     }
     DeoptimizeIf(below_equal, instr->environment());
   } else {
+    if (instr->hydrogen()->index()->representation().IsTagged() &&
+        !instr->hydrogen()->index()->type().IsSmi()) {
+      __ test(ToRegister(instr->index()), Immediate(kSmiTagMask));
+      DeoptimizeIf(not_zero, instr->environment());
+    }
     __ cmp(ToRegister(instr->index()), ToOperand(instr->length()));
     DeoptimizeIf(above_equal, instr->environment());
   }
 }
 
 
 void LCodeGen::DoStoreKeyedExternalArray(LStoreKeyed* instr) {
   ElementsKind elements_kind = instr->elements_kind();
   LOperand* key = instr->key();
   if (!key->IsConstantOperand() &&
       ExternalArrayOpRequiresTemp(instr->hydrogen()->key()->representation(),
                                   elements_kind)) {
     __ SmiUntag(ToRegister(key));
   }
   Operand operand(BuildFastArrayOperand(
       instr->elements(),
       key,
       instr->hydrogen()->key()->representation(),
       elements_kind,
       0,
       instr->additional_index()));
   if (elements_kind == EXTERNAL_FLOAT_ELEMENTS) {
+    CpuFeatures::Scope scope(SSE2);
     __ cvtsd2ss(xmm0, ToDoubleRegister(instr->value()));
     __ movss(operand, xmm0);
   } else if (elements_kind == EXTERNAL_DOUBLE_ELEMENTS) {
+    CpuFeatures::Scope scope(SSE2);
     __ movdbl(operand, ToDoubleRegister(instr->value()));
   } else {
     Register value = ToRegister(instr->value());
     switch (elements_kind) {
       case EXTERNAL_PIXEL_ELEMENTS:
       case EXTERNAL_UNSIGNED_BYTE_ELEMENTS:
       case EXTERNAL_BYTE_ELEMENTS:
         __ mov_b(operand, value);
         break;
       case EXTERNAL_SHORT_ELEMENTS:
@@ skipping 15 matching lines @@
       case DICTIONARY_ELEMENTS:
       case NON_STRICT_ARGUMENTS_ELEMENTS:
         UNREACHABLE();
         break;
     }
   }
 }
 
 
 void LCodeGen::DoStoreKeyedFixedDoubleArray(LStoreKeyed* instr) {
+  CpuFeatures::Scope scope(SSE2);
   XMMRegister value = ToDoubleRegister(instr->value());
 
   if (instr->NeedsCanonicalization()) {
     Label have_value;
 
     __ ucomisd(value, value);
     __ j(parity_odd, &have_value);  // NaN.
 
     ExternalReference canonical_nan_reference =
         ExternalReference::address_of_canonical_non_hole_nan();
@@ skipping 230 matching lines @@
 
 void LCodeGen::DoStringAdd(LStringAdd* instr) {
   EmitPushTaggedOperand(instr->left());
   EmitPushTaggedOperand(instr->right());
   StringAddStub stub(NO_STRING_CHECK_IN_STUB);
   CallCode(stub.GetCode(), RelocInfo::CODE_TARGET, instr);
 }
 
 
 void LCodeGen::DoInteger32ToDouble(LInteger32ToDouble* instr) {
-  LOperand* input = instr->value();
-  ASSERT(input->IsRegister() || input->IsStackSlot());
-  LOperand* output = instr->result();
-  ASSERT(output->IsDoubleRegister());
-  __ cvtsi2sd(ToDoubleRegister(output), ToOperand(input));
+  if (CpuFeatures::IsSupported(SSE2)) {
+    CpuFeatures::Scope scope(SSE2);
+    LOperand* input = instr->value();
+    ASSERT(input->IsRegister() || input->IsStackSlot());
+    LOperand* output = instr->result();
+    ASSERT(output->IsDoubleRegister());
+    __ cvtsi2sd(ToDoubleRegister(output), ToOperand(input));
+  } else {
+    UNREACHABLE();
+  }
 }
 
 
 void LCodeGen::DoUint32ToDouble(LUint32ToDouble* instr) {
+  CpuFeatures::Scope scope(SSE2);
   LOperand* input = instr->value();
   LOperand* output = instr->result();
   LOperand* temp = instr->temp();
 
   __ LoadUint32(ToDoubleRegister(output),
                 ToRegister(input),
                 ToDoubleRegister(temp));
 }
 
 
@@ skipping 57 matching lines @@
   PushSafepointRegistersScope scope(this);
 
   Label done;
 
   if (signedness == SIGNED_INT32) {
     // There was overflow, so bits 30 and 31 of the original integer
     // disagree. Try to allocate a heap number in new space and store
     // the value in there. If that fails, call the runtime system.
     __ SmiUntag(reg);
     __ xor_(reg, 0x80000000);
-    __ cvtsi2sd(xmm0, Operand(reg));
+    if (CpuFeatures::IsSupported(SSE2)) {
+      CpuFeatures::Scope feature_scope(SSE2);
+      __ cvtsi2sd(xmm0, Operand(reg));
+    } else {
+      __ push(reg);
+      __ fild_s(Operand(esp, 0));
+      __ pop(reg);
+    }
   } else {
-    __ LoadUint32(xmm0, reg, xmm1);
+    if (CpuFeatures::IsSupported(SSE2)) {
+      CpuFeatures::Scope feature_scope(SSE2);
+      __ LoadUint32(xmm0, reg, xmm1);
+    } else {
+      UNREACHABLE();
+    }
   }
 
   if (FLAG_inline_new) {
     __ AllocateHeapNumber(reg, tmp, no_reg, &slow);
     __ jmp(&done, Label::kNear);
   }
 
   // Slow case: Call the runtime system to do the number allocation.
   __ bind(&slow);
 
   // TODO(3095996): Put a valid pointer value in the stack slot where the result
   // register is stored, as this register is in the pointer map, but contains an
   // integer value.
   __ StoreToSafepointRegisterSlot(reg, Immediate(0));
   // NumberTagI and NumberTagD use the context from the frame, rather than
   // the environment's HContext or HInlinedContext value.
   // They only call Runtime::kAllocateHeapNumber.
   // The corresponding HChange instructions are added in a phase that does
   // not have easy access to the local context.
   __ mov(esi, Operand(ebp, StandardFrameConstants::kContextOffset));
   __ CallRuntimeSaveDoubles(Runtime::kAllocateHeapNumber);
   RecordSafepointWithRegisters(
       instr->pointer_map(), 0, Safepoint::kNoLazyDeopt);
   if (!reg.is(eax)) __ mov(reg, eax);
 
   // Done. Put the value in xmm0 into the value of the allocated heap
   // number.
   __ bind(&done);
-  __ movdbl(FieldOperand(reg, HeapNumber::kValueOffset), xmm0);
+  if (CpuFeatures::IsSupported(SSE2)) {
+    CpuFeatures::Scope feature_scope(SSE2);
+    __ movdbl(FieldOperand(reg, HeapNumber::kValueOffset), xmm0);
+  } else {
+    __ fstp_d(FieldOperand(reg, HeapNumber::kValueOffset));
+  }
   __ StoreToSafepointRegisterSlot(reg, reg);
 }
 
 
 void LCodeGen::DoNumberTagD(LNumberTagD* instr) {
   class DeferredNumberTagD: public LDeferredCode {
    public:
     DeferredNumberTagD(LCodeGen* codegen, LNumberTagD* instr)
         : LDeferredCode(codegen), instr_(instr) { }
     virtual void Generate() { codegen()->DoDeferredNumberTagD(instr_); }
     virtual LInstruction* instr() { return instr_; }
    private:
     LNumberTagD* instr_;
   };
 
-  XMMRegister input_reg = ToDoubleRegister(instr->value());
   Register reg = ToRegister(instr->result());
   Register tmp = ToRegister(instr->temp());
 
   DeferredNumberTagD* deferred = new(zone()) DeferredNumberTagD(this, instr);
   if (FLAG_inline_new) {
     __ AllocateHeapNumber(reg, tmp, no_reg, deferred->entry());
   } else {
     __ jmp(deferred->entry());
   }
   __ bind(deferred->exit());
-  __ movdbl(FieldOperand(reg, HeapNumber::kValueOffset), input_reg);
+  if (CpuFeatures::IsSupported(SSE2)) {
+    CpuFeatures::Scope scope(SSE2);
+    XMMRegister input_reg = ToDoubleRegister(instr->value());
+    __ movdbl(FieldOperand(reg, HeapNumber::kValueOffset), input_reg);
+  } else {
+    if (!IsX87TopOfStack(instr->value())) {
+    __ fld_d(ToOperand(instr->value()));
+    }
+    __ fstp_d(FieldOperand(reg, HeapNumber::kValueOffset));
+  }
 }
 
 
 void LCodeGen::DoDeferredNumberTagD(LNumberTagD* instr) {
   // TODO(3095996): Get rid of this. For now, we need to make the
   // result register contain a valid pointer because it is already
   // contained in the register pointer map.
   Register reg = ToRegister(instr->result());
   __ Set(reg, Immediate(0));
 
@@ skipping 134 matching lines @@
       __ cmp(input_reg, 0x80000000u);
       __ j(not_equal, &done);
       // Check if the input was 0x8000000 (kMinInt).
       // If no, then we got an overflow and we deoptimize.
       ExternalReference min_int = ExternalReference::address_of_min_int();
       __ movdbl(xmm_temp, Operand::StaticVariable(min_int));
       __ ucomisd(xmm_temp, xmm0);
       DeoptimizeIf(not_equal, instr->environment());
       DeoptimizeIf(parity_even, instr->environment());  // NaN.
     }
-  } else {
+  } else if (CpuFeatures::IsSupported(SSE2)) {
+    CpuFeatures::Scope scope(SSE2);
     // Deoptimize if we don't have a heap number.
     DeoptimizeIf(not_equal, instr->environment());
 
     XMMRegister xmm_temp = ToDoubleRegister(instr->temp());
     __ movdbl(xmm0, FieldOperand(input_reg, HeapNumber::kValueOffset));
     __ cvttsd2si(input_reg, Operand(xmm0));
     __ cvtsi2sd(xmm_temp, Operand(input_reg));
     __ ucomisd(xmm0, xmm_temp);
     DeoptimizeIf(not_equal, instr->environment());
     DeoptimizeIf(parity_even, instr->environment());  // NaN.
     if (instr->hydrogen()->CheckFlag(HValue::kBailoutOnMinusZero)) {
       __ test(input_reg, Operand(input_reg));
       __ j(not_zero, &done);
       __ movmskpd(input_reg, xmm0);
       __ and_(input_reg, 1);
       DeoptimizeIf(not_zero, instr->environment());
     }
+  } else {
+    UNREACHABLE();
   }
   __ bind(&done);
 }
 
 
 void LCodeGen::DoTaggedToI(LTaggedToI* instr) {
   class DeferredTaggedToI: public LDeferredCode {
    public:
     DeferredTaggedToI(LCodeGen* codegen, LTaggedToI* instr)
         : LDeferredCode(codegen), instr_(instr) { }
@@ skipping 22 matching lines @@
 
 
 void LCodeGen::DoNumberUntagD(LNumberUntagD* instr) {
   LOperand* input = instr->value();
   ASSERT(input->IsRegister());
   LOperand* temp = instr->temp();
   ASSERT(temp == NULL || temp->IsRegister());
   LOperand* result = instr->result();
   ASSERT(result->IsDoubleRegister());
 
-  Register input_reg = ToRegister(input);
-  XMMRegister result_reg = ToDoubleRegister(result);
+  if (CpuFeatures::IsSupported(SSE2)) {
+    CpuFeatures::Scope scope(SSE2);
+    Register input_reg = ToRegister(input);
+    XMMRegister result_reg = ToDoubleRegister(result);
 
-  bool deoptimize_on_minus_zero =
-      instr->hydrogen()->deoptimize_on_minus_zero();
-  Register temp_reg = deoptimize_on_minus_zero ? ToRegister(temp) : no_reg;
+    bool deoptimize_on_minus_zero =
+        instr->hydrogen()->deoptimize_on_minus_zero();
+    Register temp_reg = deoptimize_on_minus_zero ? ToRegister(temp) : no_reg;
 
-  EmitNumberUntagD(input_reg,
-                   temp_reg,
-                   result_reg,
-                   instr->hydrogen()->deoptimize_on_undefined(),
-                   deoptimize_on_minus_zero,
-                   instr->environment());
+    EmitNumberUntagD(input_reg,
+                     temp_reg,
+                     result_reg,
+                     instr->hydrogen()->deoptimize_on_undefined(),
+                     deoptimize_on_minus_zero,
+                     instr->environment());
+  } else {
+    UNIMPLEMENTED();
+  }
 }
 
 
 void LCodeGen::DoDoubleToI(LDoubleToI* instr) {
   LOperand* input = instr->value();
   ASSERT(input->IsDoubleRegister());
   LOperand* result = instr->result();
   ASSERT(result->IsRegister());
+  CpuFeatures::Scope scope(SSE2);
 
   XMMRegister input_reg = ToDoubleRegister(input);
   Register result_reg = ToRegister(result);
 
   if (instr->truncating()) {
     // Performs a truncating conversion of a floating point number as used by
     // the JS bitwise operations.
     __ cvttsd2si(result_reg, Operand(input_reg));
     __ cmp(result_reg, 0x80000000u);
     if (CpuFeatures::IsSupported(SSE3)) {
@@ skipping 169 matching lines @@
     Operand operand = ToOperand(instr->value());
     __ cmp(operand, target);
   }
   DeoptimizeIf(not_equal, instr->environment());
 }
 
 
 void LCodeGen::DoCheckMapCommon(Register reg,
                                 Handle<Map> map,
                                 CompareMapMode mode,
-                                LEnvironment* env) {
+                                LInstruction* instr) {
   Label success;
   __ CompareMap(reg, map, &success, mode);
-  DeoptimizeIf(not_equal, env);
+  DeoptimizeIf(not_equal, instr->environment());
   __ bind(&success);
 }
 
 
 void LCodeGen::DoCheckMaps(LCheckMaps* instr) {
   LOperand* input = instr->value();
   ASSERT(input->IsRegister());
   Register reg = ToRegister(input);
 
   Label success;
   SmallMapList* map_set = instr->hydrogen()->map_set();
   for (int i = 0; i < map_set->length() - 1; i++) {
     Handle<Map> map = map_set->at(i);
     __ CompareMap(reg, map, &success, REQUIRE_EXACT_MAP);
     __ j(equal, &success);
   }
   Handle<Map> map = map_set->last();
-  DoCheckMapCommon(reg, map, REQUIRE_EXACT_MAP, instr->environment());
+  DoCheckMapCommon(reg, map, REQUIRE_EXACT_MAP, instr);
   __ bind(&success);
 }
 
 
 void LCodeGen::DoClampDToUint8(LClampDToUint8* instr) {
+  CpuFeatures::Scope scope1(SSE2);
   XMMRegister value_reg = ToDoubleRegister(instr->unclamped());
   Register result_reg = ToRegister(instr->result());
   __ ClampDoubleToUint8(value_reg, xmm0, result_reg);
 }
 
 
 void LCodeGen::DoClampIToUint8(LClampIToUint8* instr) {
   ASSERT(instr->unclamped()->Equals(instr->result()));
   Register value_reg = ToRegister(instr->result());
   __ ClampUint8(value_reg);
 }
 
 
 void LCodeGen::DoClampTToUint8(LClampTToUint8* instr) {
+  CpuFeatures::Scope scope1(SSE2);
+
   ASSERT(instr->unclamped()->Equals(instr->result()));
   Register input_reg = ToRegister(instr->unclamped());
   Label is_smi, done, heap_number;
 
   __ JumpIfSmi(input_reg, &is_smi);
 
   // Check for heap number
   __ cmp(FieldOperand(input_reg, HeapObject::kMapOffset),
          factory()->heap_number_map());
   __ j(equal, &heap_number, Label::kNear);
@@ skipping 26 matching lines @@
 
   Handle<JSObject> holder = instr->holder();
   Handle<JSObject> current_prototype = instr->prototype();
 
   // Load prototype object.
   __ LoadHeapObject(reg, current_prototype);
 
   // Check prototype maps up to the holder.
   while (!current_prototype.is_identical_to(holder)) {
     DoCheckMapCommon(reg, Handle<Map>(current_prototype->map()),
-                     ALLOW_ELEMENT_TRANSITION_MAPS, instr->environment());
+                     ALLOW_ELEMENT_TRANSITION_MAPS, instr);
 
     current_prototype =
         Handle<JSObject>(JSObject::cast(current_prototype->GetPrototype()));
     // Load next prototype object.
     __ LoadHeapObject(reg, current_prototype);
   }
 
   // Check the holder map.
   DoCheckMapCommon(reg, Handle<Map>(current_prototype->map()),
-                   ALLOW_ELEMENT_TRANSITION_MAPS, instr->environment());
+                   ALLOW_ELEMENT_TRANSITION_MAPS, instr);
 }
 
 
 void LCodeGen::DoAllocateObject(LAllocateObject* instr) {
   class DeferredAllocateObject: public LDeferredCode {
    public:
     DeferredAllocateObject(LCodeGen* codegen, LAllocateObject* instr)
         : LDeferredCode(codegen), instr_(instr) { }
     virtual void Generate() { codegen()->DoDeferredAllocateObject(instr_); }
     virtual LInstruction* instr() { return instr_; }
@@ skipping 516 matching lines @@
   __ mov(temp, Operand(temp, StandardFrameConstants::kCallerFPOffset));
 
   // Check the marker in the calling frame.
   __ bind(&check_frame_marker);
   __ cmp(Operand(temp, StandardFrameConstants::kMarkerOffset),
          Immediate(Smi::FromInt(StackFrame::CONSTRUCT)));
 }
 
 
 void LCodeGen::EnsureSpaceForLazyDeopt() {
-  // Ensure that we have enough space after the previous lazy-bailout
-  // instruction for patching the code here.
-  int current_pc = masm()->pc_offset();
-  int patch_size = Deoptimizer::patch_size();
-  if (current_pc < last_lazy_deopt_pc_ + patch_size) {
-    int padding_size = last_lazy_deopt_pc_ + patch_size - current_pc;
-    __ Nop(padding_size);
+  if (!info()->IsStub()) {
+    // Ensure that we have enough space after the previous lazy-bailout
+    // instruction for patching the code here.
+    int current_pc = masm()->pc_offset();
+    int patch_size = Deoptimizer::patch_size();
+    if (current_pc < last_lazy_deopt_pc_ + patch_size) {
+      int padding_size = last_lazy_deopt_pc_ + patch_size - current_pc;
+      __ Nop(padding_size);
+    }
   }
   last_lazy_deopt_pc_ = masm()->pc_offset();
 }
 
 
 void LCodeGen::DoLazyBailout(LLazyBailout* instr) {
   EnsureSpaceForLazyDeopt();
   ASSERT(instr->HasEnvironment());
   LEnvironment* env = instr->environment();
   RegisterEnvironmentForDeoptimization(env, Safepoint::kLazyDeopt);
@@ skipping 203 matching lines @@
                               FixedArray::kHeaderSize - kPointerSize));
   __ bind(&done);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32