Re-establish mips basic infrastructure.

src/mips/macro-assembler-mips.cc

-// Copyright 2010 the V8 project authors. All rights reserved.
+// Copyright 2011 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 <limits.h>  // For LONG_MIN, LONG_MAX
 
 #include "v8.h"
 
 #if defined(V8_TARGET_ARCH_MIPS)
 
 #include "bootstrapper.h"
 #include "codegen-inl.h"
 #include "debug.h"
 #include "runtime.h"
 
 namespace v8 {
 namespace internal {
 
 MacroAssembler::MacroAssembler(void* buffer, int size)
     : Assembler(buffer, size),
-      unresolved_(0),
       generating_stub_(false),
       allow_stub_calls_(true),
-      code_object_(Heap::undefined_value()) {
+      code_object_(HEAP->undefined_value()) {
 }
 
 
+// Arguments macros
+#define COND_TYPED_ARGS Condition cond, Register r1, const Operand& r2
+#define COND_ARGS cond, r1, r2
 
-void MacroAssembler::Jump(Register target, Condition cond,
-                          Register r1, const Operand& r2) {
-  Jump(Operand(target), cond, r1, r2);
+#define REGISTER_TARGET_BODY(Name) \
+void MacroAssembler::Name(Register target, \
+                          bool ProtectBranchDelaySlot) { \
+  Name(Operand(target), ProtectBranchDelaySlot); \
+} \
+void MacroAssembler::Name(Register target, COND_TYPED_ARGS, \
+                          bool ProtectBranchDelaySlot) { \
+  Name(Operand(target), COND_ARGS, ProtectBranchDelaySlot); \
 }
 
 
-void MacroAssembler::Jump(intptr_t target, RelocInfo::Mode rmode,
-                          Condition cond, Register r1, const Operand& r2) {
-  Jump(Operand(target, rmode), cond, r1, r2);
+#define INT_PTR_TARGET_BODY(Name) \
+void MacroAssembler::Name(intptr_t target, RelocInfo::Mode rmode, \
+                          bool ProtectBranchDelaySlot) { \
+  Name(Operand(target, rmode), ProtectBranchDelaySlot); \
+} \
+void MacroAssembler::Name(intptr_t target, \
+                          RelocInfo::Mode rmode, \
+                          COND_TYPED_ARGS, \
+                          bool ProtectBranchDelaySlot) { \
+  Name(Operand(target, rmode), COND_ARGS, ProtectBranchDelaySlot); \
 }
 
 
-void MacroAssembler::Jump(byte* target, RelocInfo::Mode rmode,
-                          Condition cond, Register r1, const Operand& r2) {
-  ASSERT(!RelocInfo::IsCodeTarget(rmode));
-  Jump(reinterpret_cast<intptr_t>(target), rmode, cond, r1, r2);
+#define BYTE_PTR_TARGET_BODY(Name) \
+void MacroAssembler::Name(byte* target, RelocInfo::Mode rmode, \
+                          bool ProtectBranchDelaySlot) { \
+  Name(reinterpret_cast<intptr_t>(target), rmode, ProtectBranchDelaySlot); \
+} \
+void MacroAssembler::Name(byte* target, \
+                          RelocInfo::Mode rmode, \
+                          COND_TYPED_ARGS, \
+                          bool ProtectBranchDelaySlot) { \
+  Name(reinterpret_cast<intptr_t>(target), \
+       rmode, \
+       COND_ARGS, \
+       ProtectBranchDelaySlot); \
 }
 
 
-void MacroAssembler::Jump(Handle<Code> code, RelocInfo::Mode rmode,
-                          Condition cond, Register r1, const Operand& r2) {
-  ASSERT(RelocInfo::IsCodeTarget(rmode));
-  Jump(reinterpret_cast<intptr_t>(code.location()), rmode, cond);
+#define CODE_TARGET_BODY(Name) \
+void MacroAssembler::Name(Handle<Code> target, RelocInfo::Mode rmode, \
+                          bool ProtectBranchDelaySlot) { \
+  Name(reinterpret_cast<intptr_t>(target.location()), \
+       rmode, ProtectBranchDelaySlot); \
+} \
+void MacroAssembler::Name(Handle<Code> target, \
+                          RelocInfo::Mode rmode, \
+                          COND_TYPED_ARGS, \
+                          bool ProtectBranchDelaySlot) { \
+  Name(reinterpret_cast<intptr_t>(target.location()), \
+       rmode, \
+       COND_ARGS, \
+       ProtectBranchDelaySlot); \
 }
 
 
-void MacroAssembler::Call(Register target,
-                          Condition cond, Register r1, const Operand& r2) {
-  Call(Operand(target), cond, r1, r2);
+REGISTER_TARGET_BODY(Jump)
+REGISTER_TARGET_BODY(Call)
+INT_PTR_TARGET_BODY(Jump)
+INT_PTR_TARGET_BODY(Call)
+BYTE_PTR_TARGET_BODY(Jump)
+BYTE_PTR_TARGET_BODY(Call)
+CODE_TARGET_BODY(Jump)
+CODE_TARGET_BODY(Call)
+
+#undef COND_TYPED_ARGS
+#undef COND_ARGS
+#undef REGISTER_TARGET_BODY
+#undef BYTE_PTR_TARGET_BODY
+#undef CODE_TARGET_BODY
+
+
+void MacroAssembler::Ret(bool ProtectBranchDelaySlot) {
+  Jump(Operand(ra), ProtectBranchDelaySlot);
 }
 
 
-void MacroAssembler::Call(intptr_t target, RelocInfo::Mode rmode,
-                          Condition cond, Register r1, const Operand& r2) {
-  Call(Operand(target, rmode), cond, r1, r2);
+void MacroAssembler::Ret(Condition cond, Register r1, const Operand& r2,
+    bool ProtectBranchDelaySlot) {
+  Jump(Operand(ra), cond, r1, r2, ProtectBranchDelaySlot);
 }
 
 
-void MacroAssembler::Call(byte* target, RelocInfo::Mode rmode,
-                          Condition cond, Register r1, const Operand& r2) {
-  ASSERT(!RelocInfo::IsCodeTarget(rmode));
-  Call(reinterpret_cast<intptr_t>(target), rmode, cond, r1, r2);
-}
-
-
-void MacroAssembler::Call(Handle<Code> code, RelocInfo::Mode rmode,
-                          Condition cond, Register r1, const Operand& r2) {
-  ASSERT(RelocInfo::IsCodeTarget(rmode));
-  Call(reinterpret_cast<intptr_t>(code.location()), rmode, cond, r1, r2);
-}
-
-
-void MacroAssembler::Ret(Condition cond, Register r1, const Operand& r2) {
-  Jump(Operand(ra), cond, r1, r2);
-}
-
-
 void MacroAssembler::LoadRoot(Register destination,
                               Heap::RootListIndex index) {
   lw(destination, MemOperand(s6, index << kPointerSizeLog2));
 }
 
+
 void MacroAssembler::LoadRoot(Register destination,
                               Heap::RootListIndex index,
                               Condition cond,
                               Register src1, const Operand& src2) {
-  Branch(NegateCondition(cond), 2, src1, src2);
+  Branch(2, NegateCondition(cond), src1, src2);
   lw(destination, MemOperand(s6, index << kPointerSizeLog2));
 }
 
 
-void MacroAssembler::RecordWrite(Register object, Register offset,
+void MacroAssembler::StoreRoot(Register source,
+                               Heap::RootListIndex index) {
+  sw(source, MemOperand(s6, index << kPointerSizeLog2));
+}
+
+
+void MacroAssembler::StoreRoot(Register source,
+                               Heap::RootListIndex index,
+                               Condition cond,
+                               Register src1, const Operand& src2) {
+  Branch(2, NegateCondition(cond), src1, src2);
+  sw(source, MemOperand(s6, index << kPointerSizeLog2));
+}
+
+
+void MacroAssembler::RecordWriteHelper(Register object,
+                                       Register address,
+                                       Register scratch) {
+  if (FLAG_debug_code) {
+    // Check that the object is not in new space.
+    Label not_in_new_space;
+    InNewSpace(object, scratch, ne, &not_in_new_space);
+    Abort("new-space object passed to RecordWriteHelper");
+    bind(&not_in_new_space);
+  }
+
+  // Calculate page address: Clear bits from 0 to kPageSizeBits.
+  if (mips32r2) {
+    Ins(object, zero_reg, 0, kPageSizeBits);
+  } else {
+    // The Ins macro is slow on r1, so use shifts instead.
+    srl(object, object, kPageSizeBits);
+    sll(object, object, kPageSizeBits);
+  }
+
+  // Calculate region number.
+  Ext(address, address, Page::kRegionSizeLog2,
+      kPageSizeBits - Page::kRegionSizeLog2);
+
+  // Mark region dirty.
+  lw(scratch, MemOperand(object, Page::kDirtyFlagOffset));
+  li(at, Operand(1));
+  sllv(at, at, address);
+  or_(scratch, scratch, at);
+  sw(scratch, MemOperand(object, Page::kDirtyFlagOffset));
+}
+
+
+void MacroAssembler::InNewSpace(Register object,
+                                Register scratch,
+                                Condition cc,
+                                Label* branch) {
+  ASSERT(cc == eq || cc == ne);
+  And(scratch, object, Operand(ExternalReference::new_space_mask(isolate())));
+  Branch(branch, cc, scratch,
+         Operand(ExternalReference::new_space_start(isolate())));
+}
+
+
+// Will clobber 4 registers: object, scratch0, scratch1, at. The
+// register 'object' contains a heap object pointer.  The heap object
+// tag is shifted away.
+void MacroAssembler::RecordWrite(Register object,
+                                 Operand offset,
+                                 Register scratch0,
+                                 Register scratch1) {
+  // The compiled code assumes that record write doesn't change the
+  // context register, so we check that none of the clobbered
+  // registers are cp.
+  ASSERT(!object.is(cp) && !scratch0.is(cp) && !scratch1.is(cp));
+
+  Label done;
+
+  // First, test that the object is not in the new space.  We cannot set
+  // region marks for new space pages.
+  InNewSpace(object, scratch0, eq, &done);
+
+  // Add offset into the object.
+  Addu(scratch0, object, offset);
+
+  // Record the actual write.
+  RecordWriteHelper(object, scratch0, scratch1);
+
+  bind(&done);
+
+  // Clobber all input registers when running with the debug-code flag
+  // turned on to provoke errors.
+  if (FLAG_debug_code) {
+    li(object, Operand(BitCast<int32_t>(kZapValue)));
+    li(scratch0, Operand(BitCast<int32_t>(kZapValue)));
+    li(scratch1, Operand(BitCast<int32_t>(kZapValue)));
+  }
+}
+
+
+// Will clobber 4 registers: object, address, scratch, ip.  The
+// register 'object' contains a heap object pointer.  The heap object
+// tag is shifted away.
+void MacroAssembler::RecordWrite(Register object,
+                                 Register address,
                                  Register scratch) {
-  UNIMPLEMENTED_MIPS();
+  // The compiled code assumes that record write doesn't change the
+  // context register, so we check that none of the clobbered
+  // registers are cp.
+  ASSERT(!object.is(cp) && !address.is(cp) && !scratch.is(cp));
+
+  Label done;
+
+  // First, test that the object is not in the new space.  We cannot set
+  // region marks for new space pages.
+  InNewSpace(object, scratch, eq, &done);
+
+  // Record the actual write.
+  RecordWriteHelper(object, address, scratch);
+
+  bind(&done);
+
+  // Clobber all input registers when running with the debug-code flag
+  // turned on to provoke errors.
+  if (FLAG_debug_code) {
+    li(object, Operand(BitCast<int32_t>(kZapValue)));
+    li(address, Operand(BitCast<int32_t>(kZapValue)));
+    li(scratch, Operand(BitCast<int32_t>(kZapValue)));
+  }
+}
+
+
+// -----------------------------------------------------------------------------
+// Allocation support
+
+
+void MacroAssembler::CheckAccessGlobalProxy(Register holder_reg,
+                                            Register scratch,
+                                            Label* miss) {
+  Label same_contexts;
+
+  ASSERT(!holder_reg.is(scratch));
+  ASSERT(!holder_reg.is(at));
+  ASSERT(!scratch.is(at));
+
+  // Load current lexical context from the stack frame.
+  lw(scratch, MemOperand(fp, StandardFrameConstants::kContextOffset));
+  // In debug mode, make sure the lexical context is set.
+#ifdef DEBUG
+  Check(ne, "we should not have an empty lexical context",
+      scratch, Operand(zero_reg));
+#endif
+
+  // Load the global context of the current context.
+  int offset = Context::kHeaderSize + Context::GLOBAL_INDEX * kPointerSize;
+  lw(scratch, FieldMemOperand(scratch, offset));
+  lw(scratch, FieldMemOperand(scratch, GlobalObject::kGlobalContextOffset));
+
+  // Check the context is a global context.
+  if (FLAG_debug_code) {
+    // TODO(119): Avoid push(holder_reg)/pop(holder_reg).
+    Push(holder_reg);  // Temporarily save holder on the stack.
+    // Read the first word and compare to the global_context_map.
+    lw(holder_reg, FieldMemOperand(scratch, HeapObject::kMapOffset));
+    LoadRoot(at, Heap::kGlobalContextMapRootIndex);
+    Check(eq, "JSGlobalObject::global_context should be a global context.",
+          holder_reg, Operand(at));
+    Pop(holder_reg);  // Restore holder.
+  }
+
+  // Check if both contexts are the same.
+  lw(at, FieldMemOperand(holder_reg, JSGlobalProxy::kContextOffset));
+  Branch(&same_contexts, eq, scratch, Operand(at));
+
+  // Check the context is a global context.
+  if (FLAG_debug_code) {
+    // TODO(119): Avoid push(holder_reg)/pop(holder_reg).
+    Push(holder_reg);  // Temporarily save holder on the stack.
+    mov(holder_reg, at);  // Move at to its holding place.
+    LoadRoot(at, Heap::kNullValueRootIndex);
+    Check(ne, "JSGlobalProxy::context() should not be null.",
+          holder_reg, Operand(at));
+
+    lw(holder_reg, FieldMemOperand(holder_reg, HeapObject::kMapOffset));
+    LoadRoot(at, Heap::kGlobalContextMapRootIndex);
+    Check(eq, "JSGlobalObject::global_context should be a global context.",
+          holder_reg, Operand(at));
+    // Restore at is not needed. at is reloaded below.
+    Pop(holder_reg);  // Restore holder.
+    // Restore at to holder's context.
+    lw(at, FieldMemOperand(holder_reg, JSGlobalProxy::kContextOffset));
+  }
+
+  // Check that the security token in the calling global object is
+  // compatible with the security token in the receiving global
+  // object.
+  int token_offset = Context::kHeaderSize +
+                     Context::SECURITY_TOKEN_INDEX * kPointerSize;
+
+  lw(scratch, FieldMemOperand(scratch, token_offset));
+  lw(at, FieldMemOperand(at, token_offset));
+  Branch(miss, ne, scratch, Operand(at));
+
+  bind(&same_contexts);
 }
 
 
 // ---------------------------------------------------------------------------
 // Instruction macros
 
-void MacroAssembler::Add(Register rd, Register rs, const Operand& rt) {
-  if (rt.is_reg()) {
-    add(rd, rs, rt.rm());
-  } else {
-    if (is_int16(rt.imm32_) && !MustUseAt(rt.rmode_)) {
-      addi(rd, rs, rt.imm32_);
-    } else {
-      // li handles the relocation.
-      ASSERT(!rs.is(at));
-      li(at, rt);
-      add(rd, rs, at);
-    }
-  }
-}
-
-
 void MacroAssembler::Addu(Register rd, Register rs, const Operand& rt) {
   if (rt.is_reg()) {
     addu(rd, rs, rt.rm());
   } else {
-    if (is_int16(rt.imm32_) && !MustUseAt(rt.rmode_)) {
+    if (is_int16(rt.imm32_) && !MustUseReg(rt.rmode_)) {
       addiu(rd, rs, rt.imm32_);
     } else {
       // li handles the relocation.
       ASSERT(!rs.is(at));
       li(at, rt);
       addu(rd, rs, at);
     }
   }
 }
+
+
+void MacroAssembler::Subu(Register rd, Register rs, const Operand& rt) {
+  if (rt.is_reg()) {
+    subu(rd, rs, rt.rm());
+  } else {
+    if (is_int16(rt.imm32_) && !MustUseReg(rt.rmode_)) {
+      addiu(rd, rs, -rt.imm32_);  // No subiu instr, use addiu(x, y, -imm).
+    } else {
+      // li handles the relocation.
+      ASSERT(!rs.is(at));
+      li(at, rt);
+      subu(rd, rs, at);
+    }
+  }
+}
 
 
 void MacroAssembler::Mul(Register rd, Register rs, const Operand& rt) {
   if (rt.is_reg()) {
     mul(rd, rs, rt.rm());
   } else {
     // li handles the relocation.
     ASSERT(!rs.is(at));
     li(at, rt);
     mul(rd, rs, at);
@@ skipping 46 matching lines @@
     li(at, rt);
     divu(rs, at);
   }
 }
 
 
 void MacroAssembler::And(Register rd, Register rs, const Operand& rt) {
   if (rt.is_reg()) {
     and_(rd, rs, rt.rm());
   } else {
-    if (is_int16(rt.imm32_) && !MustUseAt(rt.rmode_)) {
+    if (is_uint16(rt.imm32_) && !MustUseReg(rt.rmode_)) {
       andi(rd, rs, rt.imm32_);
     } else {
       // li handles the relocation.
       ASSERT(!rs.is(at));
       li(at, rt);
       and_(rd, rs, at);
     }
   }
 }
 
 
 void MacroAssembler::Or(Register rd, Register rs, const Operand& rt) {
   if (rt.is_reg()) {
     or_(rd, rs, rt.rm());
   } else {
-    if (is_int16(rt.imm32_) && !MustUseAt(rt.rmode_)) {
+    if (is_uint16(rt.imm32_) && !MustUseReg(rt.rmode_)) {
       ori(rd, rs, rt.imm32_);
     } else {
       // li handles the relocation.
       ASSERT(!rs.is(at));
       li(at, rt);
       or_(rd, rs, at);
     }
   }
 }
 
 
 void MacroAssembler::Xor(Register rd, Register rs, const Operand& rt) {
   if (rt.is_reg()) {
     xor_(rd, rs, rt.rm());
   } else {
-    if (is_int16(rt.imm32_) && !MustUseAt(rt.rmode_)) {
+    if (is_uint16(rt.imm32_) && !MustUseReg(rt.rmode_)) {
       xori(rd, rs, rt.imm32_);
     } else {
       // li handles the relocation.
       ASSERT(!rs.is(at));
       li(at, rt);
       xor_(rd, rs, at);
     }
   }
 }
 
 
 void MacroAssembler::Nor(Register rd, Register rs, const Operand& rt) {
   if (rt.is_reg()) {
     nor(rd, rs, rt.rm());
   } else {
     // li handles the relocation.
     ASSERT(!rs.is(at));
     li(at, rt);
     nor(rd, rs, at);
   }
 }
 
 
 void MacroAssembler::Slt(Register rd, Register rs, const Operand& rt) {
   if (rt.is_reg()) {
     slt(rd, rs, rt.rm());
   } else {
-    if (is_int16(rt.imm32_) && !MustUseAt(rt.rmode_)) {
+    if (is_int16(rt.imm32_) && !MustUseReg(rt.rmode_)) {
       slti(rd, rs, rt.imm32_);
     } else {
       // li handles the relocation.
       ASSERT(!rs.is(at));
       li(at, rt);
       slt(rd, rs, at);
     }
   }
 }
 
 
 void MacroAssembler::Sltu(Register rd, Register rs, const Operand& rt) {
   if (rt.is_reg()) {
     sltu(rd, rs, rt.rm());
   } else {
-    if (is_int16(rt.imm32_) && !MustUseAt(rt.rmode_)) {
+    if (is_uint16(rt.imm32_) && !MustUseReg(rt.rmode_)) {
       sltiu(rd, rs, rt.imm32_);
     } else {
       // li handles the relocation.
       ASSERT(!rs.is(at));
       li(at, rt);
       sltu(rd, rs, at);
     }
   }
 }
 
 
+void MacroAssembler::Ror(Register rd, Register rs, const Operand& rt) {
+  if (mips32r2) {
+    if (rt.is_reg()) {
+      rotrv(rd, rs, rt.rm());
+    } else {
+      rotr(rd, rs, rt.imm32_);
+    }
+  } else {
+    if (rt.is_reg()) {
+      subu(at, zero_reg, rt.rm());
+      sllv(at, rs, at);
+      srlv(rd, rs, rt.rm());
+      or_(rd, rd, at);
+    } else {
+      if (rt.imm32_ == 0) {
+        srl(rd, rs, 0);
+      } else {
+        srl(at, rs, rt.imm32_);
+        sll(rd, rs, (0x20 - rt.imm32_) & 0x1f);
+        or_(rd, rd, at);
+      }
+    }
+  }
+}
+
+
 //------------Pseudo-instructions-------------
 
-void MacroAssembler::movn(Register rd, Register rt) {
-  addiu(at, zero_reg, -1);  // Fill at with ones.
-  xor_(rd, rt, at);
-}
-
-
 void MacroAssembler::li(Register rd, Operand j, bool gen2instr) {
   ASSERT(!j.is_reg());
-
-  if (!MustUseAt(j.rmode_) && !gen2instr) {
+  BlockTrampolinePoolScope block_trampoline_pool(this);
+  if (!MustUseReg(j.rmode_) && !gen2instr) {
     // Normal load of an immediate value which does not need Relocation Info.
     if (is_int16(j.imm32_)) {
       addiu(rd, zero_reg, j.imm32_);
     } else if (!(j.imm32_ & HIMask)) {
       ori(rd, zero_reg, j.imm32_);
     } else if (!(j.imm32_ & LOMask)) {
       lui(rd, (HIMask & j.imm32_) >> 16);
     } else {
       lui(rd, (HIMask & j.imm32_) >> 16);
       ori(rd, rd, (LOMask & j.imm32_));
     }
-  } else if (MustUseAt(j.rmode_) || gen2instr) {
-    if (MustUseAt(j.rmode_)) {
+  } else if (MustUseReg(j.rmode_) || gen2instr) {
+    if (MustUseReg(j.rmode_)) {
       RecordRelocInfo(j.rmode_, j.imm32_);
     }
     // We need always the same number of instructions as we may need to patch
     // this code to load another value which may need 2 instructions to load.
     if (is_int16(j.imm32_)) {
       nop();
       addiu(rd, zero_reg, j.imm32_);
     } else if (!(j.imm32_ & HIMask)) {
       nop();
       ori(rd, zero_reg, j.imm32_);
@@ skipping 59 matching lines @@
 
   for (int16_t i = kNumRegisters; i > 0; i--) {
     if ((regs & (1 << i)) != 0) {
       lw(ToRegister(i), MemOperand(sp, 4 * (NumSaved++)));
     }
   }
   addiu(sp, sp, 4 * NumSaved);
 }
 
 
+void MacroAssembler::Ext(Register rt,
+                         Register rs,
+                         uint16_t pos,
+                         uint16_t size) {
+  ASSERT(pos < 32);
+  ASSERT(pos + size < 32);
+
+  if (mips32r2) {
+    ext_(rt, rs, pos, size);
+  } else {
+    // Move rs to rt and shift it left then right to get the
+    // desired bitfield on the right side and zeroes on the left.
+    sll(rt, rs, 32 - (pos + size));
+    srl(rt, rt, 32 - size);
+  }
+}
+
+
+void MacroAssembler::Ins(Register rt,
+                         Register rs,
+                         uint16_t pos,
+                         uint16_t size) {
+  ASSERT(pos < 32);
+  ASSERT(pos + size < 32);
+
+  if (mips32r2) {
+    ins_(rt, rs, pos, size);
+  } else {
+    ASSERT(!rt.is(t8) && !rs.is(t8));
+
+    srl(t8, rt, pos + size);
+    // The left chunk from rt that needs to
+    // be saved is on the right side of t8.
+    sll(at, t8, pos + size);
+    // The 'at' register now contains the left chunk on
+    // the left (proper position) and zeroes.
+    sll(t8, rt, 32 - pos);
+    // t8 now contains the right chunk on the left and zeroes.
+    srl(t8, t8, 32 - pos);
+    // t8 now contains the right chunk on
+    // the right (proper position) and zeroes.
+    or_(rt, at, t8);
+    // rt now contains the left and right chunks from the original rt
+    // in their proper position and zeroes in the middle.
+    sll(t8, rs, 32 - size);
+    // t8 now contains the chunk from rs on the left and zeroes.
+    srl(t8, t8, 32 - size - pos);
+    // t8 now contains the original chunk from rs in
+    // the middle (proper position).
+    or_(rt, rt, t8);
+    // rt now contains the result of the ins instruction in R2 mode.
+  }
+}
+
+
+void MacroAssembler::Cvt_d_uw(FPURegister fd, FPURegister fs) {
+  // Move the data from fs to t4.
+  mfc1(t4, fs);
+  return Cvt_d_uw(fd, t4);
+}
+
+
+void MacroAssembler::Cvt_d_uw(FPURegister fd, Register rs) {
+  // Convert rs to a FP value in fd (and fd + 1).
+  // We do this by converting rs minus the MSB to avoid sign conversion,
+  // then adding 2^31-1 and 1 to the result.
+
+  ASSERT(!fd.is(f20));
+  ASSERT(!rs.is(t9));
+  ASSERT(!rs.is(t8));
+
+  // Save rs's MSB to t8
+  And(t8, rs, 0x80000000);
+  // Remove rs's MSB.
+  And(t9, rs, 0x7FFFFFFF);
+  // Move t9 to fd
+  mtc1(t9, fd);
+
+  // Convert fd to a real FP value.
+  cvt_d_w(fd, fd);
+
+  Label conversion_done;
+
+  // If rs's MSB was 0, it's done.
+  // Otherwise we need to add that to the FP register.
+  Branch(&conversion_done, eq, t8, Operand(zero_reg));
+
+  // First load 2^31 - 1 into f20.
+  Or(t9, zero_reg, 0x7FFFFFFF);
+  mtc1(t9, f20);
+
+  // Convert it to FP and add it to fd.
+  cvt_d_w(f20, f20);
+  add_d(fd, fd, f20);
+  // Now add 1.
+  Or(t9, zero_reg, 1);
+  mtc1(t9, f20);
+
+  cvt_d_w(f20, f20);
+  add_d(fd, fd, f20);
+  bind(&conversion_done);
+}
+
+
+void MacroAssembler::Trunc_uw_d(FPURegister fd, FPURegister fs) {
+  Trunc_uw_d(fs, t4);
+  mtc1(t4, fd);
+}
+
+
+void MacroAssembler::Trunc_uw_d(FPURegister fd, Register rs) {
+  ASSERT(!fd.is(f22));
+  ASSERT(!rs.is(t6));
+
+  // Load 2^31 into f22.
+  Or(t6, zero_reg, 0x80000000);
+  Cvt_d_uw(f22, t6);
+
+  // Test if f22 > fd.
+  c(OLT, D, fd, f22);
+
+  Label simple_convert;
+  // If fd < 2^31 we can convert it normally.
+  bc1t(&simple_convert);
+
+  // First we subtract 2^31 from fd, then trunc it to rs
+  // and add 2^31 to rs.
+
+  sub_d(f22, fd, f22);
+  trunc_w_d(f22, f22);
+  mfc1(rs, f22);
+  or_(rs, rs, t6);
+
+  Label done;
+  Branch(&done);
+  // Simple conversion.
+  bind(&simple_convert);
+  trunc_w_d(f22, fd);
+  mfc1(rs, f22);
+
+  bind(&done);
+}
+
+
+// Tries to get a signed int32 out of a double precision floating point heap
+// number. Rounds towards 0. Branch to 'not_int32' if the double is out of the
+// 32bits signed integer range.
+// This method implementation differs from the ARM version for performance
+// reasons.
+void MacroAssembler::ConvertToInt32(Register source,
+                                    Register dest,
+                                    Register scratch,
+                                    Register scratch2,
+                                    FPURegister double_scratch,
+                                    Label *not_int32) {
+  Label right_exponent, done;
+  // Get exponent word (ENDIAN issues).
+  lw(scratch, FieldMemOperand(source, HeapNumber::kExponentOffset));
+  // Get exponent alone in scratch2.
+  And(scratch2, scratch, Operand(HeapNumber::kExponentMask));
+  // Load dest with zero.  We use this either for the final shift or
+  // for the answer.
+  mov(dest, zero_reg);
+  // Check whether the exponent matches a 32 bit signed int that is not a Smi.
+  // A non-Smi integer is 1.xxx * 2^30 so the exponent is 30 (biased).  This is
+  // the exponent that we are fastest at and also the highest exponent we can
+  // handle here.
+  const uint32_t non_smi_exponent =
+      (HeapNumber::kExponentBias + 30) << HeapNumber::kExponentShift;
+  // If we have a match of the int32-but-not-Smi exponent then skip some logic.
+  Branch(&right_exponent, eq, scratch2, Operand(non_smi_exponent));
+  // If the exponent is higher than that then go to not_int32 case.  This
+  // catches numbers that don't fit in a signed int32, infinities and NaNs.
+  Branch(not_int32, gt, scratch2, Operand(non_smi_exponent));
+
+  // We know the exponent is smaller than 30 (biased).  If it is less than
+  // 0 (biased) then the number is smaller in magnitude than 1.0 * 2^0, ie
+  // it rounds to zero.
+  const uint32_t zero_exponent =
+      (HeapNumber::kExponentBias + 0) << HeapNumber::kExponentShift;
+  Subu(scratch2, scratch2, Operand(zero_exponent));
+  // Dest already has a Smi zero.
+  Branch(&done, lt, scratch2, Operand(zero_reg));
+  if (!Isolate::Current()->cpu_features()->IsSupported(FPU)) {
+    // We have a shifted exponent between 0 and 30 in scratch2.
+    srl(dest, scratch2, HeapNumber::kExponentShift);
+    // We now have the exponent in dest.  Subtract from 30 to get
+    // how much to shift down.
+    li(at, Operand(30));
+    subu(dest, at, dest);
+  }
+  bind(&right_exponent);
+  if (Isolate::Current()->cpu_features()->IsSupported(FPU)) {
+    CpuFeatures::Scope scope(FPU);
+    // MIPS FPU instructions implementing double precision to integer
+    // conversion using round to zero. Since the FP value was qualified
+    // above, the resulting integer should be a legal int32.
+    // The original 'Exponent' word is still in scratch.
+    lwc1(double_scratch, FieldMemOperand(source, HeapNumber::kMantissaOffset));
+    mtc1(scratch, FPURegister::from_code(double_scratch.code() + 1));
+    trunc_w_d(double_scratch, double_scratch);
+    mfc1(dest, double_scratch);
+  } else {
+    // On entry, dest has final downshift, scratch has original sign/exp/mant.
+    // Save sign bit in top bit of dest.
+    And(scratch2, scratch, Operand(0x80000000));
+    Or(dest, dest, Operand(scratch2));
+    // Put back the implicit 1, just above mantissa field.
+    Or(scratch, scratch, Operand(1 << HeapNumber::kExponentShift));
+
+    // Shift up the mantissa bits to take up the space the exponent used to
+    // take. We just orred in the implicit bit so that took care of one and
+    // we want to leave the sign bit 0 so we subtract 2 bits from the shift
+    // distance. But we want to clear the sign-bit so shift one more bit
+    // left, then shift right one bit.
+    const int shift_distance = HeapNumber::kNonMantissaBitsInTopWord - 2;
+    sll(scratch, scratch, shift_distance + 1);
+    srl(scratch, scratch, 1);
+
+    // Get the second half of the double. For some exponents we don't
+    // actually need this because the bits get shifted out again, but
+    // it's probably slower to test than just to do it.
+    lw(scratch2, FieldMemOperand(source, HeapNumber::kMantissaOffset));
+    // Extract the top 10 bits, and insert those bottom 10 bits of scratch.
+    // The width of the field here is the same as the shift amount above.
+    const int field_width = shift_distance;
+    Ext(scratch2, scratch2, 32-shift_distance, field_width);
+    Ins(scratch, scratch2, 0, field_width);
+    // Move down according to the exponent.
+    srlv(scratch, scratch, dest);
+    // Prepare the negative version of our integer.
+    subu(scratch2, zero_reg, scratch);
+    // Trick to check sign bit (msb) held in dest, count leading zero.
+    // 0 indicates negative, save negative version with conditional move.
+    clz(dest, dest);
+    movz(scratch, scratch2, dest);
+    mov(dest, scratch);
+  }
+  bind(&done);
+}
+
+
 // Emulated condtional branches do not emit a nop in the branch delay slot.
-
-// Trashes the at register if no scratch register is provided.
-void MacroAssembler::Branch(Condition cond, int16_t offset, Register rs,
-                            const Operand& rt, Register scratch) {
+//
+// BRANCH_ARGS_CHECK checks that conditional jump arguments are correct.
+#define BRANCH_ARGS_CHECK(cond, rs, rt) ASSERT(                                \
+    (cond == cc_always && rs.is(zero_reg) && rt.rm().is(zero_reg)) ||          \
+    (cond != cc_always && (!rs.is(zero_reg) || !rt.rm().is(zero_reg))))
+
+
+void MacroAssembler::Branch(int16_t offset,
+                            bool ProtectBranchDelaySlot) {
+  b(offset);
+
+  // Emit a nop in the branch delay slot if required.
+  if (ProtectBranchDelaySlot)
+    nop();
+}
+
+
+void MacroAssembler::Branch(int16_t offset, Condition cond, Register rs,
+                            const Operand& rt,
+                            bool ProtectBranchDelaySlot) {
+  BRANCH_ARGS_CHECK(cond, rs, rt);
+  ASSERT(!rs.is(zero_reg));
   Register r2 = no_reg;
+  Register scratch = at;
+
   if (rt.is_reg()) {
     // We don't want any other register but scratch clobbered.
     ASSERT(!scratch.is(rs) && !scratch.is(rt.rm_));
     r2 = rt.rm_;
-  } else if (cond != cc_always) {
-    // We don't want any other register but scratch clobbered.
-    ASSERT(!scratch.is(rs));
-    r2 = scratch;
-    li(r2, rt);
+    switch (cond) {
+      case cc_always:
+        b(offset);
+        break;
+      case eq:
+        beq(rs, r2, offset);
+        break;
+      case ne:
+        bne(rs, r2, offset);
+        break;
+      // Signed comparison
+      case greater:
+        if (r2.is(zero_reg)) {
+          bgtz(rs, offset);
+        } else {
+          slt(scratch, r2, rs);
+          bne(scratch, zero_reg, offset);
+        }
+        break;
+      case greater_equal:
+        if (r2.is(zero_reg)) {
+          bgez(rs, offset);
+        } else {
+          slt(scratch, rs, r2);
+          beq(scratch, zero_reg, offset);
+        }
+        break;
+      case less:
+        if (r2.is(zero_reg)) {
+          bltz(rs, offset);
+        } else {
+          slt(scratch, rs, r2);
+          bne(scratch, zero_reg, offset);
+        }
+        break;
+      case less_equal:
+        if (r2.is(zero_reg)) {
+          blez(rs, offset);
+        } else {
+          slt(scratch, r2, rs);
+          beq(scratch, zero_reg, offset);
+        }
+        break;
+      // Unsigned comparison.
+      case Ugreater:
+        if (r2.is(zero_reg)) {
+          bgtz(rs, offset);
+        } else {
+          sltu(scratch, r2, rs);
+          bne(scratch, zero_reg, offset);
+        }
+        break;
+      case Ugreater_equal:
+        if (r2.is(zero_reg)) {
+          bgez(rs, offset);
+        } else {
+          sltu(scratch, rs, r2);
+          beq(scratch, zero_reg, offset);
+        }
+        break;
+      case Uless:
+        if (r2.is(zero_reg)) {
+          b(offset);
+        } else {
+          sltu(scratch, rs, r2);
+          bne(scratch, zero_reg, offset);
+        }
+        break;
+      case Uless_equal:
+        if (r2.is(zero_reg)) {
+          b(offset);
+        } else {
+          sltu(scratch, r2, rs);
+          beq(scratch, zero_reg, offset);
+        }
+        break;
+      default:
+        UNREACHABLE();
+    }
+  } else {
+    // Be careful to always use shifted_branch_offset only just before the
+    // branch instruction, as the location will be remember for patching the
+    // target.
+    switch (cond) {
+      case cc_always:
+        b(offset);
+        break;
+      case eq:
+        // We don't want any other register but scratch clobbered.
+        ASSERT(!scratch.is(rs));
+        r2 = scratch;
+        li(r2, rt);
+        beq(rs, r2, offset);
+        break;
+      case ne:
+        // We don't want any other register but scratch clobbered.
+        ASSERT(!scratch.is(rs));
+        r2 = scratch;
+        li(r2, rt);
+        bne(rs, r2, offset);
+        break;
+      // Signed comparison
+      case greater:
+        if (rt.imm32_ == 0) {
+          bgtz(rs, offset);
+        } else {
+          r2 = scratch;
+          li(r2, rt);
+          slt(scratch, r2, rs);
+          bne(scratch, zero_reg, offset);
+        }
+        break;
+      case greater_equal:
+        if (rt.imm32_ == 0) {
+          bgez(rs, offset);
+        } else if (is_int16(rt.imm32_)) {
+          slti(scratch, rs, rt.imm32_);
+          beq(scratch, zero_reg, offset);
+        } else {
+          r2 = scratch;
+          li(r2, rt);
+          sltu(scratch, rs, r2);
+          beq(scratch, zero_reg, offset);
+        }
+        break;
+      case less:
+        if (rt.imm32_ == 0) {
+          bltz(rs, offset);
+        } else if (is_int16(rt.imm32_)) {
+          slti(scratch, rs, rt.imm32_);
+          bne(scratch, zero_reg, offset);
+        } else {
+          r2 = scratch;
+          li(r2, rt);
+          slt(scratch, rs, r2);
+          bne(scratch, zero_reg, offset);
+        }
+        break;
+      case less_equal:
+        if (rt.imm32_ == 0) {
+          blez(rs, offset);
+        } else {
+          r2 = scratch;
+          li(r2, rt);
+          slt(scratch, r2, rs);
+          beq(scratch, zero_reg, offset);
+       }
+       break;
+      // Unsigned comparison.
+      case Ugreater:
+        if (rt.imm32_ == 0) {
+          bgtz(rs, offset);
+        } else {
+          r2 = scratch;
+          li(r2, rt);
+          sltu(scratch, r2, rs);
+          bne(scratch, zero_reg, offset);
+        }
+        break;
+      case Ugreater_equal:
+        if (rt.imm32_ == 0) {
+          bgez(rs, offset);
+        } else if (is_int16(rt.imm32_)) {
+          sltiu(scratch, rs, rt.imm32_);
+          beq(scratch, zero_reg, offset);
+        } else {
+          r2 = scratch;
+          li(r2, rt);
+          sltu(scratch, rs, r2);
+          beq(scratch, zero_reg, offset);
+        }
+        break;
+      case Uless:
+        if (rt.imm32_ == 0) {
+          b(offset);
+        } else if (is_int16(rt.imm32_)) {
+          sltiu(scratch, rs, rt.imm32_);
+          bne(scratch, zero_reg, offset);
+        } else {
+          r2 = scratch;
+          li(r2, rt);
+          sltu(scratch, rs, r2);
+          bne(scratch, zero_reg, offset);
+        }
+        break;
+      case Uless_equal:
+        if (rt.imm32_ == 0) {
+          b(offset);
+        } else {
+          r2 = scratch;
+          li(r2, rt);
+          sltu(scratch, r2, rs);
+          beq(scratch, zero_reg, offset);
+        }
+        break;
+      default:
+        UNREACHABLE();
+    }
   }
-
-  switch (cond) {
-    case cc_always:
-      b(offset);
-      break;
-    case eq:
-      beq(rs, r2, offset);
-      break;
-    case ne:
-      bne(rs, r2, offset);
-      break;
-
+  // Emit a nop in the branch delay slot if required.
+  if (ProtectBranchDelaySlot)
+    nop();
+}
+
+
+void MacroAssembler::Branch(Label* L,
+                            bool ProtectBranchDelaySlot) {
+  // We use branch_offset as an argument for the branch instructions to be sure
+  // it is called just before generating the branch instruction, as needed.
+
+  b(shifted_branch_offset(L, false));
+
+  // Emit a nop in the branch delay slot if required.
+  if (ProtectBranchDelaySlot)
+    nop();
+}
+
+
+void MacroAssembler::Branch(Label* L, Condition cond, Register rs,
+                            const Operand& rt,
+                            bool ProtectBranchDelaySlot) {
+  BRANCH_ARGS_CHECK(cond, rs, rt);
+
+  int32_t offset;
+  Register r2 = no_reg;
+  Register scratch = at;
+  if (rt.is_reg()) {
+    r2 = rt.rm_;
+    // Be careful to always use shifted_branch_offset only just before the
+    // branch instruction, as the location will be remember for patching the
+    // target.
+    switch (cond) {
+      case cc_always:
+        offset = shifted_branch_offset(L, false);
+        b(offset);
+        break;
+      case eq:
+        offset = shifted_branch_offset(L, false);
+        beq(rs, r2, offset);
+        break;
+      case ne:
+        offset = shifted_branch_offset(L, false);
+        bne(rs, r2, offset);
+        break;
       // Signed comparison
-    case greater:
-      slt(scratch, r2, rs);
-      bne(scratch, zero_reg, offset);
-      break;
-    case greater_equal:
-      slt(scratch, rs, r2);
-      beq(scratch, zero_reg, offset);
-      break;
-    case less:
-      slt(scratch, rs, r2);
-      bne(scratch, zero_reg, offset);
-      break;
-    case less_equal:
-      slt(scratch, r2, rs);
-      beq(scratch, zero_reg, offset);
-      break;
-
+      case greater:
+        if (r2.is(zero_reg)) {
+          offset = shifted_branch_offset(L, false);
+          bgtz(rs, offset);
+        } else {
+          slt(scratch, r2, rs);
+          offset = shifted_branch_offset(L, false);
+          bne(scratch, zero_reg, offset);
+        }
+        break;
+      case greater_equal:
+        if (r2.is(zero_reg)) {
+          offset = shifted_branch_offset(L, false);
+          bgez(rs, offset);
+        } else {
+          slt(scratch, rs, r2);
+          offset = shifted_branch_offset(L, false);
+          beq(scratch, zero_reg, offset);
+        }
+        break;
+      case less:
+        if (r2.is(zero_reg)) {
+          offset = shifted_branch_offset(L, false);
+          bltz(rs, offset);
+        } else {
+          slt(scratch, rs, r2);
+          offset = shifted_branch_offset(L, false);
+          bne(scratch, zero_reg, offset);
+        }
+        break;
+      case less_equal:
+        if (r2.is(zero_reg)) {
+          offset = shifted_branch_offset(L, false);
+          blez(rs, offset);
+        } else {
+          slt(scratch, r2, rs);
+          offset = shifted_branch_offset(L, false);
+          beq(scratch, zero_reg, offset);
+        }
+        break;
       // Unsigned comparison.
-    case Ugreater:
-      sltu(scratch, r2, rs);
-      bne(scratch, zero_reg, offset);
-      break;
-    case Ugreater_equal:
-      sltu(scratch, rs, r2);
-      beq(scratch, zero_reg, offset);
-      break;
-    case Uless:
-      sltu(scratch, rs, r2);
-      bne(scratch, zero_reg, offset);
-      break;
-    case Uless_equal:
-      sltu(scratch, r2, rs);
-      beq(scratch, zero_reg, offset);
-      break;
-
-    default:
-      UNREACHABLE();
+      case Ugreater:
+        if (r2.is(zero_reg)) {
+          offset = shifted_branch_offset(L, false);
+           bgtz(rs, offset);
+        } else {
+          sltu(scratch, r2, rs);
+          offset = shifted_branch_offset(L, false);
+          bne(scratch, zero_reg, offset);
+        }
+        break;
+      case Ugreater_equal:
+        if (r2.is(zero_reg)) {
+          offset = shifted_branch_offset(L, false);
+          bgez(rs, offset);
+        } else {
+          sltu(scratch, rs, r2);
+          offset = shifted_branch_offset(L, false);
+          beq(scratch, zero_reg, offset);
+        }
+        break;
+      case Uless:
+        if (r2.is(zero_reg)) {
+          offset = shifted_branch_offset(L, false);
+          b(offset);
+        } else {
+          sltu(scratch, rs, r2);
+          offset = shifted_branch_offset(L, false);
+          bne(scratch, zero_reg, offset);
+        }
+        break;
+      case Uless_equal:
+        if (r2.is(zero_reg)) {
+          offset = shifted_branch_offset(L, false);
+          b(offset);
+        } else {
+          sltu(scratch, r2, rs);
+          offset = shifted_branch_offset(L, false);
+          beq(scratch, zero_reg, offset);
+        }
+        break;
+      default:
+        UNREACHABLE();
+    }
+  } else {
+    // Be careful to always use shifted_branch_offset only just before the
+    // branch instruction, as the location will be remember for patching the
+    // target.
+    switch (cond) {
+      case cc_always:
+        offset = shifted_branch_offset(L, false);
+        b(offset);
+        break;
+      case eq:
+        r2 = scratch;
+        li(r2, rt);
+        offset = shifted_branch_offset(L, false);
+        beq(rs, r2, offset);
+        break;
+      case ne:
+        r2 = scratch;
+        li(r2, rt);
+        offset = shifted_branch_offset(L, false);
+        bne(rs, r2, offset);
+        break;
+      // Signed comparison
+      case greater:
+        if (rt.imm32_ == 0) {
+          offset = shifted_branch_offset(L, false);
+          bgtz(rs, offset);
+        } else {
+          r2 = scratch;
+          li(r2, rt);
+          slt(scratch, r2, rs);
+          offset = shifted_branch_offset(L, false);
+          bne(scratch, zero_reg, offset);
+        }
+        break;
+      case greater_equal:
+        if (rt.imm32_ == 0) {
+          offset = shifted_branch_offset(L, false);
+          bgez(rs, offset);
+        } else if (is_int16(rt.imm32_)) {
+          slti(scratch, rs, rt.imm32_);
+          offset = shifted_branch_offset(L, false);
+          beq(scratch, zero_reg, offset);
+        } else {
+          r2 = scratch;
+          li(r2, rt);
+          sltu(scratch, rs, r2);
+          offset = shifted_branch_offset(L, false);
+          beq(scratch, zero_reg, offset);
+        }
+        break;
+      case less:
+        if (rt.imm32_ == 0) {
+          offset = shifted_branch_offset(L, false);
+          bltz(rs, offset);
+        } else if (is_int16(rt.imm32_)) {
+          slti(scratch, rs, rt.imm32_);
+          offset = shifted_branch_offset(L, false);
+          bne(scratch, zero_reg, offset);
+        } else {
+          r2 = scratch;
+          li(r2, rt);
+          slt(scratch, rs, r2);
+          offset = shifted_branch_offset(L, false);
+          bne(scratch, zero_reg, offset);
+        }
+        break;
+      case less_equal:
+        if (rt.imm32_ == 0) {
+          offset = shifted_branch_offset(L, false);
+          blez(rs, offset);
+        } else {
+          r2 = scratch;
+          li(r2, rt);
+          slt(scratch, r2, rs);
+          offset = shifted_branch_offset(L, false);
+          beq(scratch, zero_reg, offset);
+        }
+        break;
+      // Unsigned comparison.
+      case Ugreater:
+        if (rt.imm32_ == 0) {
+          offset = shifted_branch_offset(L, false);
+          bgtz(rs, offset);
+        } else {
+          r2 = scratch;
+          li(r2, rt);
+          sltu(scratch, r2, rs);
+          offset = shifted_branch_offset(L, false);
+          bne(scratch, zero_reg, offset);
+        }
+        break;
+      case Ugreater_equal:
+        if (rt.imm32_ == 0) {
+          offset = shifted_branch_offset(L, false);
+          bgez(rs, offset);
+        } else if (is_int16(rt.imm32_)) {
+          sltiu(scratch, rs, rt.imm32_);
+          offset = shifted_branch_offset(L, false);
+          beq(scratch, zero_reg, offset);
+        } else {
+          r2 = scratch;
+          li(r2, rt);
+          sltu(scratch, rs, r2);
+          offset = shifted_branch_offset(L, false);
+          beq(scratch, zero_reg, offset);
+        }
+        break;
+     case Uless:
+        if (rt.imm32_ == 0) {
+          offset = shifted_branch_offset(L, false);
+          b(offset);
+        } else if (is_int16(rt.imm32_)) {
+          sltiu(scratch, rs, rt.imm32_);
+          offset = shifted_branch_offset(L, false);
+          bne(scratch, zero_reg, offset);
+        } else {
+          r2 = scratch;
+          li(r2, rt);
+          sltu(scratch, rs, r2);
+          offset = shifted_branch_offset(L, false);
+          bne(scratch, zero_reg, offset);
+        }
+        break;
+      case Uless_equal:
+        if (rt.imm32_ == 0) {
+          offset = shifted_branch_offset(L, false);
+          b(offset);
+        } else {
+          r2 = scratch;
+          li(r2, rt);
+          sltu(scratch, r2, rs);
+          offset = shifted_branch_offset(L, false);
+          beq(scratch, zero_reg, offset);
+        }
+        break;
+      default:
+        UNREACHABLE();
+    }
   }
-  // Emit a nop in the branch delay slot.
-  nop();
-}
-
-
-void MacroAssembler::Branch(Condition cond,  Label* L, Register rs,
-                            const Operand& rt, Register scratch) {
+  // Check that offset could actually hold on an int16_t.
+  ASSERT(is_int16(offset));
+  // Emit a nop in the branch delay slot if required.
+  if (ProtectBranchDelaySlot)
+    nop();
+}
+
+
+// We need to use a bgezal or bltzal, but they can't be used directly with the
+// slt instructions. We could use sub or add instead but we would miss overflow
+// cases, so we keep slt and add an intermediate third instruction.
+void MacroAssembler::BranchAndLink(int16_t offset,
+                                   bool ProtectBranchDelaySlot) {
+  bal(offset);
+
+  // Emit a nop in the branch delay slot if required.
+  if (ProtectBranchDelaySlot)
+    nop();
+}
+
+
+void MacroAssembler::BranchAndLink(int16_t offset, Condition cond, Register rs,
+                                   const Operand& rt,
+                                   bool ProtectBranchDelaySlot) {
+  BRANCH_ARGS_CHECK(cond, rs, rt);
   Register r2 = no_reg;
+  Register scratch = at;
+
   if (rt.is_reg()) {
     r2 = rt.rm_;
   } else if (cond != cc_always) {
-    r2 = scratch;
-    li(r2, rt);
-  }
-
-  // We use branch_offset as an argument for the branch instructions to be sure
-  // it is called just before generating the branch instruction, as needed.
-
-  switch (cond) {
-    case cc_always:
-      b(shifted_branch_offset(L, false));
-      break;
-    case eq:
-      beq(rs, r2, shifted_branch_offset(L, false));
-      break;
-    case ne:
-      bne(rs, r2, shifted_branch_offset(L, false));
-      break;
-
-    // Signed comparison
-    case greater:
-      slt(scratch, r2, rs);
-      bne(scratch, zero_reg, shifted_branch_offset(L, false));
-      break;
-    case greater_equal:
-      slt(scratch, rs, r2);
-      beq(scratch, zero_reg, shifted_branch_offset(L, false));
-      break;
-    case less:
-      slt(scratch, rs, r2);
-      bne(scratch, zero_reg, shifted_branch_offset(L, false));
-      break;
-    case less_equal:
-      slt(scratch, r2, rs);
-      beq(scratch, zero_reg, shifted_branch_offset(L, false));
-      break;
-
-    // Unsigned comparison.
-    case Ugreater:
-      sltu(scratch, r2, rs);
-      bne(scratch, zero_reg, shifted_branch_offset(L, false));
-      break;
-    case Ugreater_equal:
-      sltu(scratch, rs, r2);
-      beq(scratch, zero_reg, shifted_branch_offset(L, false));
-      break;
-    case Uless:
-      sltu(scratch, rs, r2);
-      bne(scratch, zero_reg, shifted_branch_offset(L, false));
-      break;
-    case Uless_equal:
-      sltu(scratch, r2, rs);
-      beq(scratch, zero_reg, shifted_branch_offset(L, false));
-      break;
-
-    default:
-      UNREACHABLE();
-  }
-  // Emit a nop in the branch delay slot.
-  nop();
-}
-
-
-// Trashes the at register if no scratch register is provided.
-// We need to use a bgezal or bltzal, but they can't be used directly with the
-// slt instructions. We could use sub or add instead but we would miss overflow
-// cases, so we keep slt and add an intermediate third instruction.
-void MacroAssembler::BranchAndLink(Condition cond, int16_t offset, Register rs,
-                                   const Operand& rt, Register scratch) {
-  Register r2 = no_reg;
-  if (rt.is_reg()) {
-    r2 = rt.rm_;
-  } else if (cond != cc_always) {
     r2 = scratch;
     li(r2, rt);
   }
 
   switch (cond) {
     case cc_always:
       bal(offset);
       break;
     case eq:
       bne(rs, r2, 2);
@@ skipping 46 matching lines @@
       break;
     case Uless_equal:
       sltu(scratch, r2, rs);
       addiu(scratch, scratch, -1);
       bltzal(scratch, offset);
       break;
 
     default:
       UNREACHABLE();
   }
-  // Emit a nop in the branch delay slot.
-  nop();
+  // Emit a nop in the branch delay slot if required.
+  if (ProtectBranchDelaySlot)
+    nop();
 }
 
 
-void MacroAssembler::BranchAndLink(Condition cond, Label* L, Register rs,
-                                   const Operand& rt, Register scratch) {
+void MacroAssembler::BranchAndLink(Label* L,
+                                   bool ProtectBranchDelaySlot) {
+  bal(shifted_branch_offset(L, false));
+
+  // Emit a nop in the branch delay slot if required.
+  if (ProtectBranchDelaySlot)
+    nop();
+}
+
+
+void MacroAssembler::BranchAndLink(Label* L, Condition cond, Register rs,
+                                   const Operand& rt,
+                                   bool ProtectBranchDelaySlot) {
+  BRANCH_ARGS_CHECK(cond, rs, rt);
+
+  int32_t offset;
   Register r2 = no_reg;
+  Register scratch = at;
   if (rt.is_reg()) {
     r2 = rt.rm_;
   } else if (cond != cc_always) {
     r2 = scratch;
     li(r2, rt);
   }
 
   switch (cond) {
     case cc_always:
-      bal(shifted_branch_offset(L, false));
+      offset = shifted_branch_offset(L, false);
+      bal(offset);
       break;
     case eq:
       bne(rs, r2, 2);
       nop();
-      bal(shifted_branch_offset(L, false));
+      offset = shifted_branch_offset(L, false);
+      bal(offset);
       break;
     case ne:
       beq(rs, r2, 2);
       nop();
-      bal(shifted_branch_offset(L, false));
+      offset = shifted_branch_offset(L, false);
+      bal(offset);
       break;
 
     // Signed comparison
     case greater:
       slt(scratch, r2, rs);
       addiu(scratch, scratch, -1);
-      bgezal(scratch, shifted_branch_offset(L, false));
+      offset = shifted_branch_offset(L, false);
+      bgezal(scratch, offset);
       break;
     case greater_equal:
       slt(scratch, rs, r2);
       addiu(scratch, scratch, -1);
-      bltzal(scratch, shifted_branch_offset(L, false));
+      offset = shifted_branch_offset(L, false);
+      bltzal(scratch, offset);
       break;
     case less:
       slt(scratch, rs, r2);
       addiu(scratch, scratch, -1);
-      bgezal(scratch, shifted_branch_offset(L, false));
+      offset = shifted_branch_offset(L, false);
+      bgezal(scratch, offset);
       break;
     case less_equal:
       slt(scratch, r2, rs);
       addiu(scratch, scratch, -1);
-      bltzal(scratch, shifted_branch_offset(L, false));
+      offset = shifted_branch_offset(L, false);
+      bltzal(scratch, offset);
       break;
 
     // Unsigned comparison.
     case Ugreater:
       sltu(scratch, r2, rs);
       addiu(scratch, scratch, -1);
-      bgezal(scratch, shifted_branch_offset(L, false));
+      offset = shifted_branch_offset(L, false);
+      bgezal(scratch, offset);
       break;
     case Ugreater_equal:
       sltu(scratch, rs, r2);
       addiu(scratch, scratch, -1);
-      bltzal(scratch, shifted_branch_offset(L, false));
+      offset = shifted_branch_offset(L, false);
+      bltzal(scratch, offset);
       break;
     case Uless:
       sltu(scratch, rs, r2);
       addiu(scratch, scratch, -1);
-      bgezal(scratch, shifted_branch_offset(L, false));
+      offset = shifted_branch_offset(L, false);
+      bgezal(scratch, offset);
       break;
     case Uless_equal:
       sltu(scratch, r2, rs);
       addiu(scratch, scratch, -1);
-      bltzal(scratch, shifted_branch_offset(L, false));
+      offset = shifted_branch_offset(L, false);
+      bltzal(scratch, offset);
       break;
 
     default:
       UNREACHABLE();
   }
-  // Emit a nop in the branch delay slot.
-  nop();
+
+  // Check that offset could actually hold on an int16_t.
+  ASSERT(is_int16(offset));
+
+  // Emit a nop in the branch delay slot if required.
+  if (ProtectBranchDelaySlot)
+    nop();
 }
 
 
 void MacroAssembler::Jump(const Operand& target,
-                          Condition cond, Register rs, const Operand& rt) {
+                          bool ProtectBranchDelaySlot) {
+  if (target.is_reg()) {
+      jr(target.rm());
+  } else {    // !target.is_reg()
+    if (!MustUseReg(target.rmode_)) {
+        j(target.imm32_);
+    } else {  // MustUseReg(target)
+      li(t9, target);
+      jr(t9);
+    }
+  }
+  // Emit a nop in the branch delay slot if required.
+  if (ProtectBranchDelaySlot)
+    nop();
+}
+
+
+void MacroAssembler::Jump(const Operand& target,
+                          Condition cond, Register rs, const Operand& rt,
+                          bool ProtectBranchDelaySlot) {
+  BRANCH_ARGS_CHECK(cond, rs, rt);
   if (target.is_reg()) {
     if (cond == cc_always) {
       jr(target.rm());
     } else {
-      Branch(NegateCondition(cond), 2, rs, rt);
+      Branch(2, NegateCondition(cond), rs, rt);
       jr(target.rm());
     }
   } else {    // !target.is_reg()
-    if (!MustUseAt(target.rmode_)) {
+    if (!MustUseReg(target.rmode_)) {
       if (cond == cc_always) {
         j(target.imm32_);
       } else {
-        Branch(NegateCondition(cond), 2, rs, rt);
+        Branch(2, NegateCondition(cond), rs, rt);
         j(target.imm32_);  // Will generate only one instruction.
       }
-    } else {  // MustUseAt(target)
-      li(at, target);
-      if (cond == cc_always) {
-        jr(at);
-      } else {
-        Branch(NegateCondition(cond), 2, rs, rt);
-        jr(at);  // Will generate only one instruction.
-      }
-    }
-  }
-  // Emit a nop in the branch delay slot.
-  nop();
-}
-
-
+    } else {  // MustUseReg(target)
+      li(t9, target);
+      if (cond == cc_always) {
+        jr(t9);
+      } else {
+        Branch(2, NegateCondition(cond), rs, rt);
+        jr(t9);  // Will generate only one instruction.
+      }
+    }
+  }
+  // Emit a nop in the branch delay slot if required.
+  if (ProtectBranchDelaySlot)
+    nop();
+}
+
+
+// Note: To call gcc-compiled C code on mips, you must call thru t9.
 void MacroAssembler::Call(const Operand& target,
-                          Condition cond, Register rs, const Operand& rt) {
+                          bool ProtectBranchDelaySlot) {
+  BlockTrampolinePoolScope block_trampoline_pool(this);
+  if (target.is_reg()) {
+      jalr(target.rm());
+  } else {    // !target.is_reg()
+    if (!MustUseReg(target.rmode_)) {
+      jal(target.imm32_);
+    } else {  // MustUseReg(target)
+      li(t9, target);
+      jalr(t9);
+    }
+  }
+  // Emit a nop in the branch delay slot if required.
+  if (ProtectBranchDelaySlot)
+    nop();
+}
+
+
+// Note: To call gcc-compiled C code on mips, you must call thru t9.
+void MacroAssembler::Call(const Operand& target,
+                          Condition cond, Register rs, const Operand& rt,
+                          bool ProtectBranchDelaySlot) {
+  BRANCH_ARGS_CHECK(cond, rs, rt);
+  BlockTrampolinePoolScope block_trampoline_pool(this);
   if (target.is_reg()) {
     if (cond == cc_always) {
       jalr(target.rm());
     } else {
-      Branch(NegateCondition(cond), 2, rs, rt);
+      Branch(2, NegateCondition(cond), rs, rt);
       jalr(target.rm());
     }
   } else {    // !target.is_reg()
-    if (!MustUseAt(target.rmode_)) {
+    if (!MustUseReg(target.rmode_)) {
       if (cond == cc_always) {
         jal(target.imm32_);
       } else {
-        Branch(NegateCondition(cond), 2, rs, rt);
+        Branch(2, NegateCondition(cond), rs, rt);
         jal(target.imm32_);  // Will generate only one instruction.
       }
-    } else {  // MustUseAt(target)
-      li(at, target);
-      if (cond == cc_always) {
-        jalr(at);
-      } else {
-        Branch(NegateCondition(cond), 2, rs, rt);
-        jalr(at);  // Will generate only one instruction.
-      }
-    }
-  }
-  // Emit a nop in the branch delay slot.
-  nop();
-}
-
-void MacroAssembler::StackLimitCheck(Label* on_stack_overflow) {
-  UNIMPLEMENTED_MIPS();
-}
-
-
-void MacroAssembler::Drop(int count, Condition cond) {
-  UNIMPLEMENTED_MIPS();
+    } else {  // MustUseReg(target)
+      li(t9, target);
+      if (cond == cc_always) {
+        jalr(t9);
+      } else {
+        Branch(2, NegateCondition(cond), rs, rt);
+        jalr(t9);  // Will generate only one instruction.
+      }
+    }
+  }
+  // Emit a nop in the branch delay slot if required.
+  if (ProtectBranchDelaySlot)
+    nop();
+}
+
+
+void MacroAssembler::Drop(int count,
+                          Condition cond,
+                          Register reg,
+                          const Operand& op) {
+  if (count <= 0) {
+    return;
+  }
+
+  Label skip;
+
+  if (cond != al) {
+    Branch(&skip, NegateCondition(cond), reg, op);
+  }
+
+  if (count > 0) {
+    addiu(sp, sp, count * kPointerSize);
+  }
+
+  if (cond != al) {
+    bind(&skip);
+  }
+}
+
+
+void MacroAssembler::DropAndRet(int drop,
+                                Condition cond,
+                                Register r1,
+                                const Operand& r2) {
+  // This is a workaround to make sure only one branch instruction is
+  // generated. It relies on Drop and Ret not creating branches if
+  // cond == cc_always.
+  Label skip;
+  if (cond != cc_always) {
+    Branch(&skip, NegateCondition(cond), r1, r2);
+  }
+
+  Drop(drop);
+  Ret();
+
+  if (cond != cc_always) {
+    bind(&skip);
+  }
+}
+
+
+void MacroAssembler::Swap(Register reg1,
+                          Register reg2,
+                          Register scratch) {
+  if (scratch.is(no_reg)) {
+    Xor(reg1, reg1, Operand(reg2));
+    Xor(reg2, reg2, Operand(reg1));
+    Xor(reg1, reg1, Operand(reg2));
+  } else {
+    mov(scratch, reg1);
+    mov(reg1, reg2);
+    mov(reg2, scratch);
+  }
 }
 
 
 void MacroAssembler::Call(Label* target) {
-  UNIMPLEMENTED_MIPS();
+  BranchAndLink(cc_always, target);
+}
+
+
+void MacroAssembler::Move(Register dst, Register src) {
+  if (!dst.is(src)) {
+    mov(dst, src);
+  }
 }
 
 
 #ifdef ENABLE_DEBUGGER_SUPPORT
-  // ---------------------------------------------------------------------------
-  // Debugger Support
-
-  void MacroAssembler::DebugBreak() {
-    UNIMPLEMENTED_MIPS();
-  }
-#endif
+
+void MacroAssembler::DebugBreak() {
+  ASSERT(allow_stub_calls());
+  mov(a0, zero_reg);
+  li(a1, Operand(ExternalReference(Runtime::kDebugBreak, isolate())));
+  CEntryStub ces(1);
+  Call(ces.GetCode(), RelocInfo::DEBUG_BREAK);
+}
+
+#endif  // ENABLE_DEBUGGER_SUPPORT
 
 
 // ---------------------------------------------------------------------------
 // Exception handling
 
 void MacroAssembler::PushTryHandler(CodeLocation try_location,
                                     HandlerType type) {
   // Adjust this code if not the case.
   ASSERT(StackHandlerConstants::kSize == 4 * kPointerSize);
   // The return address is passed in register ra.
   if (try_location == IN_JAVASCRIPT) {
     if (type == TRY_CATCH_HANDLER) {
       li(t0, Operand(StackHandler::TRY_CATCH));
     } else {
       li(t0, Operand(StackHandler::TRY_FINALLY));
     }
     ASSERT(StackHandlerConstants::kStateOffset == 1 * kPointerSize
            && StackHandlerConstants::kFPOffset == 2 * kPointerSize
            && StackHandlerConstants::kPCOffset == 3 * kPointerSize
            && StackHandlerConstants::kNextOffset == 0 * kPointerSize);
     // Save the current handler as the next handler.
-    LoadExternalReference(t2, ExternalReference(Isolate::k_handler_address));
+    li(t2, Operand(ExternalReference(Isolate::k_handler_address, isolate())));
     lw(t1, MemOperand(t2));
 
     addiu(sp, sp, -StackHandlerConstants::kSize);
     sw(ra, MemOperand(sp, 12));
     sw(fp, MemOperand(sp, 8));
     sw(t0, MemOperand(sp, 4));
     sw(t1, MemOperand(sp, 0));
 
     // Link this handler as the new current one.
     sw(sp, MemOperand(t2));
 
   } else {
     // Must preserve a0-a3, and s0 (argv).
     ASSERT(try_location == IN_JS_ENTRY);
     ASSERT(StackHandlerConstants::kStateOffset == 1 * kPointerSize
            && StackHandlerConstants::kFPOffset == 2 * kPointerSize
            && StackHandlerConstants::kPCOffset == 3 * kPointerSize
            && StackHandlerConstants::kNextOffset == 0 * kPointerSize);
 
     // The frame pointer does not point to a JS frame so we save NULL
     // for fp. We expect the code throwing an exception to check fp
     // before dereferencing it to restore the context.
     li(t0, Operand(StackHandler::ENTRY));
 
     // Save the current handler as the next handler.
-    LoadExternalReference(t2, ExternalReference(Isolate::k_handler_address));
+    li(t2, Operand(ExternalReference(Isolate::k_handler_address, isolate())));
     lw(t1, MemOperand(t2));
 
     addiu(sp, sp, -StackHandlerConstants::kSize);
     sw(ra, MemOperand(sp, 12));
     sw(zero_reg, MemOperand(sp, 8));
     sw(t0, MemOperand(sp, 4));
     sw(t1, MemOperand(sp, 0));
 
     // Link this handler as the new current one.
     sw(sp, MemOperand(t2));
   }
 }
 
 
 void MacroAssembler::PopTryHandler() {
-  UNIMPLEMENTED_MIPS();
-}
-
-
-
-// -----------------------------------------------------------------------------
-// Activation frames
-
-void MacroAssembler::SetupAlignedCall(Register scratch, int arg_count) {
-  Label extra_push, end;
-
-  andi(scratch, sp, 7);
-
-  // We check for args and receiver size on the stack, all of them word sized.
-  // We add one for sp, that we also want to store on the stack.
-  if (((arg_count + 1) % kPointerSizeLog2) == 0) {
-    Branch(ne, &extra_push, at, Operand(zero_reg));
-  } else {  // ((arg_count + 1) % 2) == 1
-    Branch(eq, &extra_push, at, Operand(zero_reg));
-  }
-
-  // Save sp on the stack.
-  mov(scratch, sp);
-  Push(scratch);
-  b(&end);
-
-  // Align before saving sp on the stack.
-  bind(&extra_push);
-  mov(scratch, sp);
-  addiu(sp, sp, -8);
-  sw(scratch, MemOperand(sp));
-
-  // The stack is aligned and sp is stored on the top.
-  bind(&end);
-}
-
-
-void MacroAssembler::ReturnFromAlignedCall() {
-  lw(sp, MemOperand(sp));
-}
-
-
+  ASSERT_EQ(0, StackHandlerConstants::kNextOffset);
+  pop(a1);
+  Addu(sp, sp, Operand(StackHandlerConstants::kSize - kPointerSize));
+  li(at, Operand(ExternalReference(Isolate::k_handler_address, isolate())));
+  sw(a1, MemOperand(at));
+}
+
+
+void MacroAssembler::AllocateInNewSpace(int object_size,
+                                        Register result,
+                                        Register scratch1,
+                                        Register scratch2,
+                                        Label* gc_required,
+                                        AllocationFlags flags) {
+  if (!FLAG_inline_new) {
+    if (FLAG_debug_code) {
+      // Trash the registers to simulate an allocation failure.
+      li(result, 0x7091);
+      li(scratch1, 0x7191);
+      li(scratch2, 0x7291);
+    }
+    jmp(gc_required);
+    return;
+  }
+
+  ASSERT(!result.is(scratch1));
+  ASSERT(!result.is(scratch2));
+  ASSERT(!scratch1.is(scratch2));
+  ASSERT(!scratch1.is(t9));
+  ASSERT(!scratch2.is(t9));
+  ASSERT(!result.is(t9));
+
+  // Make object size into bytes.
+  if ((flags & SIZE_IN_WORDS) != 0) {
+    object_size *= kPointerSize;
+  }
+  ASSERT_EQ(0, object_size & kObjectAlignmentMask);
+
+  // Check relative positions of allocation top and limit addresses.
+  // ARM adds additional checks to make sure the ldm instruction can be
+  // used. On MIPS we don't have ldm so we don't need additional checks either.
+  ExternalReference new_space_allocation_top =
+      ExternalReference::new_space_allocation_top_address(isolate());
+  ExternalReference new_space_allocation_limit =
+      ExternalReference::new_space_allocation_limit_address(isolate());
+  intptr_t top   =
+      reinterpret_cast<intptr_t>(new_space_allocation_top.address());
+  intptr_t limit =
+      reinterpret_cast<intptr_t>(new_space_allocation_limit.address());
+  ASSERT((limit - top) == kPointerSize);
+
+  // Set up allocation top address and object size registers.
+  Register topaddr = scratch1;
+  Register obj_size_reg = scratch2;
+  li(topaddr, Operand(new_space_allocation_top));
+  li(obj_size_reg, Operand(object_size));
+
+  // This code stores a temporary value in t9.
+  if ((flags & RESULT_CONTAINS_TOP) == 0) {
+    // Load allocation top into result and allocation limit into t9.
+    lw(result, MemOperand(topaddr));
+    lw(t9, MemOperand(topaddr, kPointerSize));
+  } else {
+    if (FLAG_debug_code) {
+      // Assert that result actually contains top on entry. t9 is used
+      // immediately below so this use of t9 does not cause difference with
+      // respect to register content between debug and release mode.
+      lw(t9, MemOperand(topaddr));
+      Check(eq, "Unexpected allocation top", result, Operand(t9));
+    }
+    // Load allocation limit into t9. Result already contains allocation top.
+    lw(t9, MemOperand(topaddr, limit - top));
+  }
+
+  // Calculate new top and bail out if new space is exhausted. Use result
+  // to calculate the new top.
+  Addu(scratch2, result, Operand(obj_size_reg));
+  Branch(gc_required, Ugreater, scratch2, Operand(t9));
+  sw(scratch2, MemOperand(topaddr));
+
+  // Tag object if requested.
+  if ((flags & TAG_OBJECT) != 0) {
+    Addu(result, result, Operand(kHeapObjectTag));
+  }
+}
+
+
+void MacroAssembler::AllocateInNewSpace(Register object_size,
+                                        Register result,
+                                        Register scratch1,
+                                        Register scratch2,
+                                        Label* gc_required,
+                                        AllocationFlags flags) {
+  if (!FLAG_inline_new) {
+    if (FLAG_debug_code) {
+      // Trash the registers to simulate an allocation failure.
+      li(result, 0x7091);
+      li(scratch1, 0x7191);
+      li(scratch2, 0x7291);
+    }
+    jmp(gc_required);
+    return;
+  }
+
+  ASSERT(!result.is(scratch1));
+  ASSERT(!result.is(scratch2));
+  ASSERT(!scratch1.is(scratch2));
+  ASSERT(!scratch1.is(t9) && !scratch2.is(t9) && !result.is(t9));
+
+  // Check relative positions of allocation top and limit addresses.
+  // ARM adds additional checks to make sure the ldm instruction can be
+  // used. On MIPS we don't have ldm so we don't need additional checks either.
+  ExternalReference new_space_allocation_top =
+      ExternalReference::new_space_allocation_top_address(isolate());
+  ExternalReference new_space_allocation_limit =
+      ExternalReference::new_space_allocation_limit_address(isolate());
+  intptr_t top   =
+      reinterpret_cast<intptr_t>(new_space_allocation_top.address());
+  intptr_t limit =
+      reinterpret_cast<intptr_t>(new_space_allocation_limit.address());
+  ASSERT((limit - top) == kPointerSize);
+
+  // Set up allocation top address and object size registers.
+  Register topaddr = scratch1;
+  li(topaddr, Operand(new_space_allocation_top));
+
+  // This code stores a temporary value in t9.
+  if ((flags & RESULT_CONTAINS_TOP) == 0) {
+    // Load allocation top into result and allocation limit into t9.
+    lw(result, MemOperand(topaddr));
+    lw(t9, MemOperand(topaddr, kPointerSize));
+  } else {
+    if (FLAG_debug_code) {
+      // Assert that result actually contains top on entry. t9 is used
+      // immediately below so this use of t9 does not cause difference with
+      // respect to register content between debug and release mode.
+      lw(t9, MemOperand(topaddr));
+      Check(eq, "Unexpected allocation top", result, Operand(t9));
+    }
+    // Load allocation limit into t9. Result already contains allocation top.
+    lw(t9, MemOperand(topaddr, limit - top));
+  }
+
+  // Calculate new top and bail out if new space is exhausted. Use result
+  // to calculate the new top. Object size may be in words so a shift is
+  // required to get the number of bytes.
+  if ((flags & SIZE_IN_WORDS) != 0) {
+    sll(scratch2, object_size, kPointerSizeLog2);
+    Addu(scratch2, result, scratch2);
+  } else {
+    Addu(scratch2, result, Operand(object_size));
+  }
+  Branch(gc_required, Ugreater, scratch2, Operand(t9));
+
+  // Update allocation top. result temporarily holds the new top.
+  if (FLAG_debug_code) {
+    And(t9, scratch2, Operand(kObjectAlignmentMask));
+    Check(eq, "Unaligned allocation in new space", t9, Operand(zero_reg));
+  }
+  sw(scratch2, MemOperand(topaddr));
+
+  // Tag object if requested.
+  if ((flags & TAG_OBJECT) != 0) {
+    Addu(result, result, Operand(kHeapObjectTag));
+  }
+}
+
+
+void MacroAssembler::UndoAllocationInNewSpace(Register object,
+                                              Register scratch) {
+  ExternalReference new_space_allocation_top =
+      ExternalReference::new_space_allocation_top_address(isolate());
+
+  // Make sure the object has no tag before resetting top.
+  And(object, object, Operand(~kHeapObjectTagMask));
+#ifdef DEBUG
+  // Check that the object un-allocated is below the current top.
+  li(scratch, Operand(new_space_allocation_top));
+  lw(scratch, MemOperand(scratch));
+  Check(less, "Undo allocation of non allocated memory",
+      object, Operand(scratch));
+#endif
+  // Write the address of the object to un-allocate as the current top.
+  li(scratch, Operand(new_space_allocation_top));
+  sw(object, MemOperand(scratch));
+}
+
+
+void MacroAssembler::AllocateTwoByteString(Register result,
+                                           Register length,
+                                           Register scratch1,
+                                           Register scratch2,
+                                           Register scratch3,
+                                           Label* gc_required) {
+  // Calculate the number of bytes needed for the characters in the string while
+  // observing object alignment.
+  ASSERT((SeqTwoByteString::kHeaderSize & kObjectAlignmentMask) == 0);
+  sll(scratch1, length, 1);  // Length in bytes, not chars.
+  addiu(scratch1, scratch1,
+       kObjectAlignmentMask + SeqTwoByteString::kHeaderSize);
+  And(scratch1, scratch1, Operand(~kObjectAlignmentMask));
+
+  // Allocate two-byte string in new space.
+  AllocateInNewSpace(scratch1,
+                     result,
+                     scratch2,
+                     scratch3,
+                     gc_required,
+                     TAG_OBJECT);
+
+  // Set the map, length and hash field.
+  InitializeNewString(result,
+                     length,
+                     Heap::kStringMapRootIndex,
+                     scratch1,
+                     scratch2);
+}
+
+
+void MacroAssembler::AllocateAsciiString(Register result,
+                                         Register length,
+                                         Register scratch1,
+                                         Register scratch2,
+                                         Register scratch3,
+                                         Label* gc_required) {
+  // Calculate the number of bytes needed for the characters in the string
+  // while observing object alignment.
+  ASSERT((SeqAsciiString::kHeaderSize & kObjectAlignmentMask) == 0);
+  ASSERT(kCharSize == 1);
+  addiu(scratch1, length, kObjectAlignmentMask + SeqAsciiString::kHeaderSize);
+  And(scratch1, scratch1, Operand(~kObjectAlignmentMask));
+
+  // Allocate ASCII string in new space.
+  AllocateInNewSpace(scratch1,
+                     result,
+                     scratch2,
+                     scratch3,
+                     gc_required,
+                     TAG_OBJECT);
+
+  // Set the map, length and hash field.
+  InitializeNewString(result,
+                     length,
+                     Heap::kAsciiStringMapRootIndex,
+                     scratch1,
+                     scratch2);
+}
+
+
+void MacroAssembler::AllocateTwoByteConsString(Register result,
+                                               Register length,
+                                               Register scratch1,
+                                               Register scratch2,
+                                               Label* gc_required) {
+  AllocateInNewSpace(ConsString::kSize,
+                     result,
+                     scratch1,
+                     scratch2,
+                     gc_required,
+                     TAG_OBJECT);
+  InitializeNewString(result,
+                     length,
+                     Heap::kConsStringMapRootIndex,
+                     scratch1,
+                     scratch2);
+}
+
+
+void MacroAssembler::AllocateAsciiConsString(Register result,
+                                             Register length,
+                                             Register scratch1,
+                                             Register scratch2,
+                                             Label* gc_required) {
+  AllocateInNewSpace(ConsString::kSize,
+                     result,
+                     scratch1,
+                     scratch2,
+                     gc_required,
+                     TAG_OBJECT);
+  InitializeNewString(result,
+                    length,
+                    Heap::kConsAsciiStringMapRootIndex,
+                    scratch1,
+                    scratch2);
+}
+
+
+// Allocates a heap number or jumps to the label if the young space is full and
+// a scavenge is needed.
+void MacroAssembler::AllocateHeapNumber(Register result,

[Søren Thygesen Gjesse, 2011/03/24 22:11:19]

Indentation off.

[Paul Lind, 2011/03/26 18:39:17]

Done here, and in several nearby places.

+                               Register scratch1,
+                               Register scratch2,
+                               Register heap_number_map,
+                               Label* need_gc) {
+  // Allocate an object in the heap for the heap number and tag it as a heap
+  // object.
+  // We ask for four more bytes to align it as we need and align the result.
+  // (HeapNumber::kSize is modified to be 4-byte bigger)
+  AllocateInNewSpace(HeapNumber::kSize,

[Søren Thygesen Gjesse, 2011/03/24 22:11:19]

Indentation off.

[Paul Lind, 2011/03/26 18:39:17]

Done.

+                        result,
+                        scratch1,
+                        scratch2,
+                        need_gc,
+                        TAG_OBJECT);
+
+  // Align to 8 bytes. [Commented out pending code review.]
+  // __ addiu(result, result, 7-1);  // -1 because result is tagged.
+  // __ And(result, result, Operand(~7));
+  // __ Or(result, result, Operand(1));  // Tag it back.
+
+#ifdef DEBUG

[Søren Thygesen Gjesse, 2011/03/24 22:11:19]

Code in comments.

[Paul Lind, 2011/03/26 18:39:17]

Removed. Was an early artifact of trying to align HeapNumbers to 8-byte boundary
for mips, which we might want to revisit someday.

+//  // TODO(MIPS.6)
+//  // Check that the result is 8-byte aligned.
+//  andi(scratch2, result, Operand(7));
+//  xori(scratch2, scratch2, Operand(1));  // Fail if the tag is missing.
+//  Check(eq,
+//          "Error in HeapNumber alloc (not 8-byte aligned or tag missing)",
+//          scratch2, Operand(zero_reg));
+#endif
+
+  // Store heap number map in the allocated object.
+  AssertRegisterIsRoot(heap_number_map, Heap::kHeapNumberMapRootIndex);
+  sw(heap_number_map, FieldMemOperand(result, HeapObject::kMapOffset));
+}
+
+
+void MacroAssembler::AllocateHeapNumberWithValue(Register result,
+                                                 FPURegister value,
+                                                 Register scratch1,
+                                                 Register scratch2,
+                                                 Label* gc_required) {
+  LoadRoot(t6, Heap::kHeapNumberMapRootIndex);
+  AllocateHeapNumber(result, scratch1, scratch2, t6, gc_required);
+  sdc1(value, FieldMemOperand(result, HeapNumber::kValueOffset));
+}
+
+
+// Copies a fixed number of fields of heap objects from src to dst.
+void MacroAssembler::CopyFields(Register dst,
+                                Register src,
+                                RegList temps,
+                                int field_count) {
+  ASSERT((temps & dst.bit()) == 0);
+  ASSERT((temps & src.bit()) == 0);
+  // Primitive implementation using only one temporary register.
+
+  Register tmp = no_reg;
+  // Find a temp register in temps list.
+  for (int i = 0; i < kNumRegisters; i++) {
+    if ((temps & (1 << i)) != 0) {
+      tmp.code_ = i;
+      break;
+    }
+  }
+  ASSERT(!tmp.is(no_reg));
+
+  for (int i = 0; i < field_count; i++) {
+    lw(tmp, FieldMemOperand(src, i * kPointerSize));
+    sw(tmp, FieldMemOperand(dst, i * kPointerSize));
+  }
+}
+
+
+void MacroAssembler::CheckMap(Register obj,
+                              Register scratch,
+                              Handle<Map> map,
+                              Label* fail,
+                              bool is_heap_object) {
+  if (!is_heap_object) {
+    JumpIfSmi(obj, fail);
+  }
+  lw(scratch, FieldMemOperand(obj, HeapObject::kMapOffset));
+  li(at, Operand(map));
+  Branch(fail, ne, scratch, Operand(at));
+}
+
+
+void MacroAssembler::CheckMap(Register obj,
+                              Register scratch,
+                              Heap::RootListIndex index,
+                              Label* fail,
+                              bool is_heap_object) {
+  if (!is_heap_object) {
+    JumpIfSmi(obj, fail);
+  }
+  lw(scratch, FieldMemOperand(obj, HeapObject::kMapOffset));
+  LoadRoot(at, index);
+  Branch(fail, ne, scratch, Operand(at));
+}
+
+
 // -----------------------------------------------------------------------------
 // JavaScript invokes
 
 void MacroAssembler::InvokePrologue(const ParameterCount& expected,
                                     const ParameterCount& actual,
                                     Handle<Code> code_constant,
                                     Register code_reg,
                                     Label* done,
-                                    InvokeFlag flag) {
+                                    InvokeFlag flag,
+                                    PostCallGenerator* post_call_generator) {
   bool definitely_matches = false;
   Label regular_invoke;
 
   // Check whether the expected and actual arguments count match. If not,
   // setup registers according to contract with ArgumentsAdaptorTrampoline:
   //  a0: actual arguments count
   //  a1: function (passed through to callee)
   //  a2: expected arguments count
   //  a3: callee code entry
 
@@ skipping 14 matching lines @@
       if (expected.immediate() == sentinel) {
         // Don't worry about adapting arguments for builtins that
         // don't want that done. Skip adaption code by making it look
         // like we have a match between expected and actual number of
         // arguments.
         definitely_matches = true;
       } else {
         li(a2, Operand(expected.immediate()));
       }
     }
-  } else if (actual.is_immediate()) {
-    Branch(eq, &regular_invoke, expected.reg(), Operand(actual.immediate()));
-    li(a0, Operand(actual.immediate()));
   } else {
-    Branch(eq, &regular_invoke, expected.reg(), Operand(actual.reg()));
+    if (actual.is_immediate()) {
+      Branch(&regular_invoke, eq, expected.reg(), Operand(actual.immediate()));
+      li(a0, Operand(actual.immediate()));
+    } else {
+      Branch(&regular_invoke, eq, expected.reg(), Operand(actual.reg()));
+    }
   }
 
   if (!definitely_matches) {
     if (!code_constant.is_null()) {
       li(a3, Operand(code_constant));
       addiu(a3, a3, Code::kHeaderSize - kHeapObjectTag);
     }
 
-    ExternalReference adaptor(Builtins::ArgumentsAdaptorTrampoline);
+    Handle<Code> adaptor =
+        Handle<Code>(Isolate::Current()->builtins()->builtin(
+            Builtins::ArgumentsAdaptorTrampoline));
     if (flag == CALL_FUNCTION) {
-      CallBuiltin(adaptor);
-      b(done);
-      nop();
+      Call(adaptor, RelocInfo::CODE_TARGET);
+      if (post_call_generator != NULL) post_call_generator->Generate();
+      jmp(done);
     } else {
-      JumpToBuiltin(adaptor);
+      Jump(adaptor, RelocInfo::CODE_TARGET);
     }
     bind(&regular_invoke);
   }
 }
 
+
 void MacroAssembler::InvokeCode(Register code,
                                 const ParameterCount& expected,
                                 const ParameterCount& actual,
-                                InvokeFlag flag) {
+                                InvokeFlag flag,
+                                PostCallGenerator* post_call_generator) {
   Label done;
 
-  InvokePrologue(expected, actual, Handle<Code>::null(), code, &done, flag);
+  InvokePrologue(expected, actual, Handle<Code>::null(), code, &done, flag,
+                 post_call_generator);
   if (flag == CALL_FUNCTION) {
     Call(code);
   } else {
     ASSERT(flag == JUMP_FUNCTION);
     Jump(code);
   }
   // Continue here if InvokePrologue does handle the invocation due to
   // mismatched parameter counts.
   bind(&done);
 }
@@ skipping 13 matching lines @@
     Jump(code, rmode);
   }
   // Continue here if InvokePrologue does handle the invocation due to
   // mismatched parameter counts.
   bind(&done);
 }
 
 
 void MacroAssembler::InvokeFunction(Register function,
                                     const ParameterCount& actual,
-                                    InvokeFlag flag) {
+                                    InvokeFlag flag,
+                                    PostCallGenerator* post_call_generator) {
   // Contract with called JS functions requires that function is passed in a1.
   ASSERT(function.is(a1));
   Register expected_reg = a2;
   Register code_reg = a3;
 
   lw(code_reg, FieldMemOperand(a1, JSFunction::kSharedFunctionInfoOffset));
   lw(cp, FieldMemOperand(a1, JSFunction::kContextOffset));
   lw(expected_reg,
       FieldMemOperand(code_reg,
                       SharedFunctionInfo::kFormalParameterCountOffset));
-  lw(code_reg,
-      MemOperand(code_reg, SharedFunctionInfo::kCodeOffset - kHeapObjectTag));
-  addiu(code_reg, code_reg, Code::kHeaderSize - kHeapObjectTag);
+  sra(expected_reg, expected_reg, kSmiTagSize);
+  lw(code_reg, FieldMemOperand(a1, JSFunction::kCodeEntryOffset));
 
   ParameterCount expected(expected_reg);
-  InvokeCode(code_reg, expected, actual, flag);
+  InvokeCode(code_reg, expected, actual, flag, post_call_generator);
+}
+
+
+void MacroAssembler::InvokeFunction(JSFunction* function,
+                                    const ParameterCount& actual,
+                                    InvokeFlag flag) {
+  ASSERT(function->is_compiled());
+
+  // Get the function and setup the context.
+  li(a1, Operand(Handle<JSFunction>(function)));
+  lw(cp, FieldMemOperand(a1, JSFunction::kContextOffset));
+
+  // Invoke the cached code.
+  Handle<Code> code(function->code());
+  ParameterCount expected(function->shared()->formal_parameter_count());
+  if (V8::UseCrankshaft()) {
+    UNIMPLEMENTED_MIPS();
+  } else {
+    InvokeCode(code, expected, actual, RelocInfo::CODE_TARGET, flag);
+  }
+}
+
+
+void MacroAssembler::IsObjectJSObjectType(Register heap_object,
+                                          Register map,
+                                          Register scratch,
+                                          Label* fail) {
+  lw(map, FieldMemOperand(heap_object, HeapObject::kMapOffset));
+  IsInstanceJSObjectType(map, scratch, fail);
+}
+
+
+void MacroAssembler::IsInstanceJSObjectType(Register map,
+                                            Register scratch,
+                                            Label* fail) {
+  lbu(scratch, FieldMemOperand(map, Map::kInstanceTypeOffset));
+  Branch(fail, lt, scratch, Operand(FIRST_JS_OBJECT_TYPE));
+  Branch(fail, gt, scratch, Operand(LAST_JS_OBJECT_TYPE));
+}
+
+
+void MacroAssembler::IsObjectJSStringType(Register object,
+                                          Register scratch,
+                                          Label* fail) {
+  ASSERT(kNotStringTag != 0);
+
+  lw(scratch, FieldMemOperand(object, HeapObject::kMapOffset));
+  lbu(scratch, FieldMemOperand(scratch, Map::kInstanceTypeOffset));
+  And(scratch, scratch, Operand(kIsNotStringMask));
+  Branch(fail, ne, scratch, Operand(zero_reg));
 }
 
 
 // ---------------------------------------------------------------------------
 // Support functions.
 
-  void MacroAssembler::GetObjectType(Register function,
-                                     Register map,
-                                     Register type_reg) {
-    lw(map, FieldMemOperand(function, HeapObject::kMapOffset));
-    lbu(type_reg, FieldMemOperand(map, Map::kInstanceTypeOffset));
-  }
+
+void MacroAssembler::TryGetFunctionPrototype(Register function,
+                                             Register result,
+                                             Register scratch,
+                                             Label* miss) {
+  // Check that the receiver isn't a smi.
+  JumpIfSmi(function, miss);
+
+  // Check that the function really is a function.  Load map into result reg.
+  GetObjectType(function, result, scratch);
+  Branch(miss, ne, scratch, Operand(JS_FUNCTION_TYPE));
+
+  // Make sure that the function has an instance prototype.
+  Label non_instance;
+  lbu(scratch, FieldMemOperand(result, Map::kBitFieldOffset));
+  And(scratch, scratch, Operand(1 << Map::kHasNonInstancePrototype));
+  Branch(&non_instance, ne, scratch, Operand(zero_reg));
+
+  // Get the prototype or initial map from the function.
+  lw(result,

[Søren Thygesen Gjesse, 2011/03/24 22:11:19]

Indentation.

[Paul Lind, 2011/03/26 18:39:17]

Done.

+      FieldMemOperand(function, JSFunction::kPrototypeOrInitialMapOffset));
+
+  // If the prototype or initial map is the hole, don't return it and
+  // simply miss the cache instead. This will allow us to allocate a
+  // prototype object on-demand in the runtime system.
+  LoadRoot(t8, Heap::kTheHoleValueRootIndex);
+  Branch(miss, eq, result, Operand(t8));
+
+  // If the function does not have an initial map, we're done.
+  Label done;
+  GetObjectType(result, scratch, scratch);
+  Branch(&done, ne, scratch, Operand(MAP_TYPE));
+
+  // Get the prototype from the initial map.
+  lw(result, FieldMemOperand(result, Map::kPrototypeOffset));
+  jmp(&done);
+
+  // Non-instance prototype: Fetch prototype from constructor field
+  // in initial map.
+  bind(&non_instance);
+  lw(result, FieldMemOperand(result, Map::kConstructorOffset));
+
+  // All done.
+  bind(&done);
+}
 
 
-  void MacroAssembler::CallBuiltin(ExternalReference builtin_entry) {
-    // Load builtin address.
-    LoadExternalReference(t9, builtin_entry);
-    lw(t9, MemOperand(t9));  // Deref address.
-    addiu(t9, t9, Code::kHeaderSize - kHeapObjectTag);
-    // Call and allocate arguments slots.
-    jalr(t9);
-    // Use the branch delay slot to allocated argument slots.
-    addiu(sp, sp, -StandardFrameConstants::kRArgsSlotsSize);
-    addiu(sp, sp, StandardFrameConstants::kRArgsSlotsSize);
-  }
-
-
-  void MacroAssembler::CallBuiltin(Register target) {
-    // Target already holds target address.
-    // Call and allocate arguments slots.
-    jalr(target);
-    // Use the branch delay slot to allocated argument slots.
-    addiu(sp, sp, -StandardFrameConstants::kRArgsSlotsSize);
-    addiu(sp, sp, StandardFrameConstants::kRArgsSlotsSize);
-  }
-
-
-  void MacroAssembler::JumpToBuiltin(ExternalReference builtin_entry) {
-    // Load builtin address.
-    LoadExternalReference(t9, builtin_entry);
-    lw(t9, MemOperand(t9));  // Deref address.
-    addiu(t9, t9, Code::kHeaderSize - kHeapObjectTag);
-    // Call and allocate arguments slots.
-    jr(t9);
-    // Use the branch delay slot to allocated argument slots.
-    addiu(sp, sp, -StandardFrameConstants::kRArgsSlotsSize);
-  }
-
-
-  void MacroAssembler::JumpToBuiltin(Register target) {
-    // t9 already holds target address.
-    // Call and allocate arguments slots.
-    jr(t9);
-    // Use the branch delay slot to allocated argument slots.
-    addiu(sp, sp, -StandardFrameConstants::kRArgsSlotsSize);
-  }
+void MacroAssembler::GetObjectType(Register object,
+                                   Register map,
+                                   Register type_reg) {
+  lw(map, FieldMemOperand(object, HeapObject::kMapOffset));
+  lbu(type_reg, FieldMemOperand(map, Map::kInstanceTypeOffset));
+}
 
 
 // -----------------------------------------------------------------------------
 // Runtime calls
 
 void MacroAssembler::CallStub(CodeStub* stub, Condition cond,
                               Register r1, const Operand& r2) {
   ASSERT(allow_stub_calls());  // Stub calls are not allowed in some stubs.
   Call(stub->GetCode(), RelocInfo::CODE_TARGET, cond, r1, r2);
 }
 
 
-void MacroAssembler::StubReturn(int argc) {
-  UNIMPLEMENTED_MIPS();
+void MacroAssembler::TailCallStub(CodeStub* stub) {
+  ASSERT(allow_stub_calls());  // stub calls are not allowed in some stubs
+  Jump(stub->GetCode(), RelocInfo::CODE_TARGET);
 }
 
 
 void MacroAssembler::IllegalOperation(int num_arguments) {
   if (num_arguments > 0) {
     addiu(sp, sp, num_arguments * kPointerSize);
   }
   LoadRoot(v0, Heap::kUndefinedValueRootIndex);
 }
 
 
-void MacroAssembler::CallRuntime(Runtime::Function* f, int num_arguments) {
+void MacroAssembler::IndexFromHash(Register hash,
+                                   Register index) {
+  // If the hash field contains an array index pick it out. The assert checks
+  // that the constants for the maximum number of digits for an array index
+  // cached in the hash field and the number of bits reserved for it does not
+  // conflict.
+  ASSERT(TenToThe(String::kMaxCachedArrayIndexLength) <
+         (1 << String::kArrayIndexValueBits));
+  // We want the smi-tagged index in key.  kArrayIndexValueMask has zeros in
+  // the low kHashShift bits.
+  STATIC_ASSERT(kSmiTag == 0);
+  Ext(hash, hash, String::kHashShift, String::kArrayIndexValueBits);
+  sll(index, hash, kSmiTagSize);
+}
+
+
+void MacroAssembler::ObjectToDoubleFPURegister(Register object,
+                                               FPURegister result,
+                                               Register scratch1,
+                                               Register scratch2,
+                                               Register heap_number_map,
+                                               Label* not_number,
+                                               ObjectToDoubleFlags flags) {
+  Label done;
+  if ((flags & OBJECT_NOT_SMI) == 0) {
+    Label not_smi;
+    JumpIfNotSmi(object, &not_smi);
+    // Remove smi tag and convert to double.
+    sra(scratch1, object, kSmiTagSize);
+    mtc1(scratch1, result);
+    cvt_d_w(result, result);
+    Branch(&done);
+    bind(&not_smi);
+  }
+  // Check for heap number and load double value from it.
+  lw(scratch1, FieldMemOperand(object, HeapObject::kMapOffset));
+  Subu(scratch2, object, Operand(kHeapObjectTag));
+  Branch(not_number, ne, scratch1, Operand(heap_number_map));
+
+  if ((flags & AVOID_NANS_AND_INFINITIES) != 0) {
+    // If exponent is all ones the number is either a NaN or +/-Infinity.
+    lw(scratch1, FieldMemOperand(object, HeapNumber::kExponentOffset));

[Søren Thygesen Gjesse, 2011/03/24 22:11:19]

What is the purpose of this block?

[Paul Lind, 2011/03/26 18:39:17]

There is no reason for the extra block-scope. Removed.

I also tightened up the code for mips. Older version copied the arm code a bit
too closely, trying to emulate an instruction we don't have.

+    {
+      // Signed bitfield extraction, based on ARM's Sbfx macro.
+      // We cannot use the ext instruction, because it doesn't sign-extend.
+      int lsb = HeapNumber::kExponentShift;
+      int width = HeapNumber::kExponentBits;
+      Register dst = scratch1;
+      Register src = scratch1;
+
+      int mask = (1 << (width + lsb)) - 1 - ((1 << lsb) - 1);
+      And(dst, src, mask);
+      int shift_up = 32 - lsb - width;
+      int shift_down = lsb + shift_up;
+      if (shift_up != 0) {
+        sll(dst, dst, shift_up);
+      }
+      if (shift_down != 0) {
+        sra(dst, dst, shift_down);
+      }
+    }
+    // All-one value sign extend to -1.
+    Branch(not_number, eq, scratch1, Operand(-1));
+  }
+  ldc1(result, MemOperand(scratch2, HeapNumber::kValueOffset));
+  bind(&done);
+}
+
+
+void MacroAssembler::SmiToDoubleFPURegister(Register smi,
+                                            FPURegister value,
+                                            Register scratch1) {
+  sra(scratch1, smi, kSmiTagSize);
+  mtc1(scratch1, value);
+  cvt_d_w(value, value);
+}
+
+
+void MacroAssembler::CallRuntime(const Runtime::Function* f,
+                                 int num_arguments) {
   // All parameters are on the stack. v0 has the return value after call.
 
   // If the expected number of arguments of the runtime function is
   // constant, we check that the actual number of arguments match the
   // expectation.
   if (f->nargs >= 0 && f->nargs != num_arguments) {
     IllegalOperation(num_arguments);
     return;
   }
 
   // TODO(1236192): Most runtime routines don't need the number of
   // arguments passed in because it is constant. At some point we
   // should remove this need and make the runtime routine entry code
   // smarter.
   li(a0, num_arguments);
-  LoadExternalReference(a1, ExternalReference(f));
+  li(a1, Operand(ExternalReference(f, isolate())));
   CEntryStub stub(1);
   CallStub(&stub);
 }
 
 
+void MacroAssembler::CallRuntimeSaveDoubles(Runtime::FunctionId id) {
+  const Runtime::Function* function = Runtime::FunctionForId(id);
+  li(a0, Operand(function->nargs));
+  li(a1, Operand(ExternalReference(function, isolate())));
+  CEntryStub stub(1);
+  stub.SaveDoubles();
+  CallStub(&stub);
+}
+
+
 void MacroAssembler::CallRuntime(Runtime::FunctionId fid, int num_arguments) {
   CallRuntime(Runtime::FunctionForId(fid), num_arguments);
 }
 
 
+void MacroAssembler::CallExternalReference(const ExternalReference& ext,
+                                           int num_arguments) {
+  li(a0, Operand(num_arguments));
+  li(a1, Operand(ext));
+
+  CEntryStub stub(1);
+  CallStub(&stub);
+}
+
+
 void MacroAssembler::TailCallExternalReference(const ExternalReference& ext,
                                                int num_arguments,
                                                int result_size) {
-  UNIMPLEMENTED_MIPS();
+  // TODO(1236192): Most runtime routines don't need the number of
+  // arguments passed in because it is constant. At some point we
+  // should remove this need and make the runtime routine entry code
+  // smarter.
+  li(a0, Operand(num_arguments));
+  JumpToExternalReference(ext);
 }
 
 
 void MacroAssembler::TailCallRuntime(Runtime::FunctionId fid,
                                      int num_arguments,
                                      int result_size) {
-  TailCallExternalReference(ExternalReference(fid), num_arguments, result_size);
+  TailCallExternalReference(ExternalReference(fid, isolate()),
+                            num_arguments,
+                            result_size);
 }
 
 
 void MacroAssembler::JumpToExternalReference(const ExternalReference& builtin) {
-  UNIMPLEMENTED_MIPS();
-}
-
-
-Handle<Code> MacroAssembler::ResolveBuiltin(Builtins::JavaScript id,
-                                            bool* resolved) {
-  UNIMPLEMENTED_MIPS();
-  return Handle<Code>(reinterpret_cast<Code*>(NULL));   // UNIMPLEMENTED RETURN
+  li(a1, Operand(builtin));
+  CEntryStub stub(1);
+  Jump(stub.GetCode(), RelocInfo::CODE_TARGET);
 }
 
 
 void MacroAssembler::InvokeBuiltin(Builtins::JavaScript id,
-                                   InvokeJSFlags flags) {
-  UNIMPLEMENTED_MIPS();
+                                   InvokeJSFlags flags,
+                                   PostCallGenerator* post_call_generator) {
+  GetBuiltinEntry(t9, id);
+  if (flags == CALL_JS) {
+    Call(t9);
+    if (post_call_generator != NULL) post_call_generator->Generate();
+  } else {
+    ASSERT(flags == JUMP_JS);
+    Jump(t9);
+  }
+}
+
+
+void MacroAssembler::GetBuiltinFunction(Register target,
+                                        Builtins::JavaScript id) {
+  // Load the builtins object into target register.
+  lw(target, MemOperand(cp, Context::SlotOffset(Context::GLOBAL_INDEX)));
+  lw(target, FieldMemOperand(target, GlobalObject::kBuiltinsOffset));
+  // Load the JavaScript builtin function from the builtins object.
+  lw(target, FieldMemOperand(target,
+                          JSBuiltinsObject::OffsetOfFunctionWithId(id)));
 }
 
 
 void MacroAssembler::GetBuiltinEntry(Register target, Builtins::JavaScript id) {
-  UNIMPLEMENTED_MIPS();
+  ASSERT(!target.is(a1));
+  GetBuiltinFunction(a1, id);
+  // Load the code entry point from the builtins object.
+  lw(target, FieldMemOperand(a1, JSFunction::kCodeEntryOffset));
 }
 
 
 void MacroAssembler::SetCounter(StatsCounter* counter, int value,
                                 Register scratch1, Register scratch2) {
-  UNIMPLEMENTED_MIPS();
+  if (FLAG_native_code_counters && counter->Enabled()) {
+    li(scratch1, Operand(value));
+    li(scratch2, Operand(ExternalReference(counter)));
+    sw(scratch1, MemOperand(scratch2));
+  }
 }
 
 
 void MacroAssembler::IncrementCounter(StatsCounter* counter, int value,
                                       Register scratch1, Register scratch2) {
-  UNIMPLEMENTED_MIPS();
+  ASSERT(value > 0);
+  if (FLAG_native_code_counters && counter->Enabled()) {
+    li(scratch2, Operand(ExternalReference(counter)));
+    lw(scratch1, MemOperand(scratch2));
+    Addu(scratch1, scratch1, Operand(value));
+    sw(scratch1, MemOperand(scratch2));
+  }
 }
 
 
 void MacroAssembler::DecrementCounter(StatsCounter* counter, int value,
                                       Register scratch1, Register scratch2) {
-  UNIMPLEMENTED_MIPS();
+  ASSERT(value > 0);
+  if (FLAG_native_code_counters && counter->Enabled()) {
+    li(scratch2, Operand(ExternalReference(counter)));
+    lw(scratch1, MemOperand(scratch2));
+    Subu(scratch1, scratch1, Operand(value));
+    sw(scratch1, MemOperand(scratch2));
+  }
 }
 
 
 // -----------------------------------------------------------------------------
 // Debugging
 
 void MacroAssembler::Assert(Condition cc, const char* msg,
                             Register rs, Operand rt) {
-  UNIMPLEMENTED_MIPS();
+  if (FLAG_debug_code)
+    Check(cc, msg, rs, rt);
+}
+
+
+void MacroAssembler::AssertRegisterIsRoot(Register reg,
+                                          Heap::RootListIndex index) {
+  if (FLAG_debug_code) {
+    LoadRoot(at, index);
+    Check(eq, "Register did not match expected root", reg, Operand(at));
+  }
+}
+
+
+void MacroAssembler::AssertFastElements(Register elements) {
+  if (FLAG_debug_code) {
+    ASSERT(!elements.is(at));
+    Label ok;
+    Push(elements);
+    lw(elements, FieldMemOperand(elements, HeapObject::kMapOffset));
+    LoadRoot(at, Heap::kFixedArrayMapRootIndex);
+    Branch(&ok, eq, elements, Operand(at));
+    LoadRoot(at, Heap::kFixedCOWArrayMapRootIndex);
+    Branch(&ok, eq, elements, Operand(at));
+    Abort("JSObject with fast elements map has slow elements");
+    bind(&ok);
+    Pop(elements);
+  }
 }
 
 
 void MacroAssembler::Check(Condition cc, const char* msg,
                            Register rs, Operand rt) {
-  UNIMPLEMENTED_MIPS();
+  Label L;
+  Branch(&L, cc, rs, rt);
+  Abort(msg);
+  // will not return here
+  bind(&L);
 }
 
 
 void MacroAssembler::Abort(const char* msg) {
-  UNIMPLEMENTED_MIPS();
+  Label abort_start;
+  bind(&abort_start);
+  // We want to pass the msg string like a smi to avoid GC
+  // problems, however msg is not guaranteed to be aligned
+  // properly. Instead, we pass an aligned pointer that is
+  // a proper v8 smi, but also pass the alignment difference
+  // from the real pointer as a smi.
+  intptr_t p1 = reinterpret_cast<intptr_t>(msg);
+  intptr_t p0 = (p1 & ~kSmiTagMask) + kSmiTag;
+  ASSERT(reinterpret_cast<Object*>(p0)->IsSmi());
+#ifdef DEBUG
+  if (msg != NULL) {
+    RecordComment("Abort message: ");
+    RecordComment(msg);
+  }
+#endif
+  // Disable stub call restrictions to always allow calls to abort.
+  AllowStubCallsScope allow_scope(this, true);
+
+  li(a0, Operand(p0));
+  Push(a0);
+  li(a0, Operand(Smi::FromInt(p1 - p0)));
+  Push(a0);
+  CallRuntime(Runtime::kAbort, 2);
+  // will not return here
+  if (is_trampoline_pool_blocked()) {
+    // If the calling code cares about the exact number of
+    // instructions generated, we insert padding here to keep the size
+    // of the Abort macro constant.
+    // Currently in debug mode with debug_code enabled the number of
+    // generated instructions is 14, so we use this as a maximum value.
+    static const int kExpectedAbortInstructions = 14;
+    int abort_instructions = InstructionsGeneratedSince(&abort_start);
+    ASSERT(abort_instructions <= kExpectedAbortInstructions);
+    while (abort_instructions++ < kExpectedAbortInstructions) {
+      nop();
+    }
+  }
+}
+
+
+void MacroAssembler::LoadContext(Register dst, int context_chain_length) {
+  if (context_chain_length > 0) {
+    // Move up the chain of contexts to the context containing the slot.
+    lw(dst, MemOperand(cp, Context::SlotOffset(Context::CLOSURE_INDEX)));
+    // Load the function context (which is the incoming, outer context).
+    lw(dst, FieldMemOperand(dst, JSFunction::kContextOffset));
+    for (int i = 1; i < context_chain_length; i++) {
+      lw(dst, MemOperand(dst, Context::SlotOffset(Context::CLOSURE_INDEX)));
+      lw(dst, FieldMemOperand(dst, JSFunction::kContextOffset));
+    }
+    // The context may be an intermediate context, not a function context.
+    lw(dst, MemOperand(dst, Context::SlotOffset(Context::FCONTEXT_INDEX)));
+  } else {  // Slot is in the current function context.
+    // The context may be an intermediate context, not a function context.
+    lw(dst, MemOperand(cp, Context::SlotOffset(Context::FCONTEXT_INDEX)));
+  }
+}
+
+
+void MacroAssembler::LoadGlobalFunction(int index, Register function) {
+  // Load the global or builtins object from the current context.
+  lw(function, MemOperand(cp, Context::SlotOffset(Context::GLOBAL_INDEX)));
+  // Load the global context from the global or builtins object.
+  lw(function, FieldMemOperand(function,
+                               GlobalObject::kGlobalContextOffset));
+  // Load the function from the global context.
+  lw(function, MemOperand(function, Context::SlotOffset(index)));
+}
+
+
+void MacroAssembler::LoadGlobalFunctionInitialMap(Register function,
+                                                  Register map,
+                                                  Register scratch) {
+  // Load the initial map. The global functions all have initial maps.
+  lw(map, FieldMemOperand(function, JSFunction::kPrototypeOrInitialMapOffset));
+  if (FLAG_debug_code) {
+    Label ok, fail;
+    CheckMap(map, scratch, Heap::kMetaMapRootIndex, &fail, false);
+    Branch(&ok);
+    bind(&fail);
+    Abort("Global functions must have initial map");
+    bind(&ok);
+  }
 }
 
 
 void MacroAssembler::EnterFrame(StackFrame::Type type) {
   addiu(sp, sp, -5 * kPointerSize);
-  li(t0, Operand(Smi::FromInt(type)));
-  li(t1, Operand(CodeObject()));
+  li(t8, Operand(Smi::FromInt(type)));
+  li(t9, Operand(CodeObject()));
   sw(ra, MemOperand(sp, 4 * kPointerSize));
   sw(fp, MemOperand(sp, 3 * kPointerSize));
   sw(cp, MemOperand(sp, 2 * kPointerSize));
-  sw(t0, MemOperand(sp, 1 * kPointerSize));
-  sw(t1, MemOperand(sp, 0 * kPointerSize));
+  sw(t8, MemOperand(sp, 1 * kPointerSize));
+  sw(t9, MemOperand(sp, 0 * kPointerSize));
   addiu(fp, sp, 3 * kPointerSize);
 }
 
 
 void MacroAssembler::LeaveFrame(StackFrame::Type type) {
   mov(sp, fp);
   lw(fp, MemOperand(sp, 0 * kPointerSize));
   lw(ra, MemOperand(sp, 1 * kPointerSize));
   addiu(sp, sp, 2 * kPointerSize);
 }
 
 
-void MacroAssembler::EnterExitFrame(ExitFrame::Mode mode,
-                                    Register hold_argc,
+void MacroAssembler::EnterExitFrame(Register hold_argc,
                                     Register hold_argv,
-                                    Register hold_function) {
-  // Compute the argv pointer and keep it in a callee-saved register.
+                                    Register hold_function,
+                                    bool save_doubles) {
   // a0 is argc.
-  sll(t0, a0, kPointerSizeLog2);
-  add(hold_argv, sp, t0);
-  addi(hold_argv, hold_argv, -kPointerSize);
+  sll(t8, a0, kPointerSizeLog2);
+  addu(hold_argv, sp, t8);
+  addiu(hold_argv, hold_argv, -kPointerSize);
 
   // Compute callee's stack pointer before making changes and save it as
-  // t1 register so that it is restored as sp register on exit, thereby
+  // t9 register so that it is restored as sp register on exit, thereby
   // popping the args.
-  // t1 = sp + kPointerSize * #args
-  add(t1, sp, t0);
+  // t9 = sp + kPointerSize * #args
+  addu(t9, sp, t8);
+
+  // Compute the argv pointer and keep it in a callee-saved register.
+  // This only seems to be needed for crankshaft and may cause problems
+  // so it's disabled for now.
+  // Subu(s6, t9, Operand(kPointerSize));
 
   // Align the stack at this point.
   AlignStack(0);
 
   // Save registers.
   addiu(sp, sp, -12);
-  sw(t1, MemOperand(sp, 8));
+  sw(t9, MemOperand(sp, 8));
   sw(ra, MemOperand(sp, 4));
   sw(fp, MemOperand(sp, 0));
   mov(fp, sp);  // Setup new frame pointer.
 
-  // Push debug marker.
-  if (mode == ExitFrame::MODE_DEBUG) {
-    Push(zero_reg);
-  } else {
-    li(t0, Operand(CodeObject()));
-    Push(t0);
-  }
+  li(t8, Operand(CodeObject()));
+  Push(t8);  // Accessed from ExitFrame::code_slot.
 
   // Save the frame pointer and the context in top.
-  LoadExternalReference(t0, ExternalReference(Isolate::k_c_entry_fp_address));
-  sw(fp, MemOperand(t0));
-  LoadExternalReference(t0, ExternalReference(Isolate::k_context_address));
-  sw(cp, MemOperand(t0));
+  li(t8, Operand(ExternalReference(Isolate::k_c_entry_fp_address, isolate())));
+  sw(fp, MemOperand(t8));
+  li(t8, Operand(ExternalReference(Isolate::k_context_address, isolate())));
+  sw(cp, MemOperand(t8));
 
   // Setup argc and the builtin function in callee-saved registers.
   mov(hold_argc, a0);
   mov(hold_function, a1);
+
+  // Optionally save all double registers.
+  if (save_doubles) {
+#ifdef DEBUG
+    int frame_alignment = ActivationFrameAlignment();
+#endif

[Søren Thygesen Gjesse, 2011/03/24 22:11:19]

The comment about vstrm is ARM specific.

[Paul Lind, 2011/03/26 18:39:17]

Done.

+    // TODO(regis): Use vstrm instruction.
+    // The stack alignment code above made sp unaligned, so add space for one
+    // more double register and use aligned addresses.
+    ASSERT(kDoubleSize == frame_alignment);
+    // Mark the frame as containing doubles by pushing a non-valid return
+    // address, i.e. 0.
+    ASSERT(ExitFrameConstants::kMarkerOffset == -2 * kPointerSize);
+    push(zero_reg);  // Marker and alignment word.
+    int space = FPURegister::kNumRegisters * kDoubleSize + kPointerSize;
+    Subu(sp, sp, Operand(space));
+    // Remember: we only need to save every 2nd double FPU value.
+    for (int i = 0; i < FPURegister::kNumRegisters; i+=2) {
+      FPURegister reg = FPURegister::from_code(i);
+      sdc1(reg, MemOperand(sp, i * kDoubleSize + kPointerSize));
+    }
+    // Note that f0 will be accessible at fp - 2*kPointerSize -
+    // FPURegister::kNumRegisters * kDoubleSize, since the code slot and the
+    // alignment word were pushed after the fp.
+  }
 }
 
 
-void MacroAssembler::LeaveExitFrame(ExitFrame::Mode mode) {
+void MacroAssembler::LeaveExitFrame(bool save_doubles) {
+  // Optionally restore all double registers.
+  if (save_doubles) {
+    // TODO(regis): Use vldrm instruction.
+    // Remember: we only need to restore every 2nd double FPU value.
+    for (int i = 0; i < FPURegister::kNumRegisters; i+=2) {
+      FPURegister reg = FPURegister::from_code(i);
+      // Register f30-f31 is just below the marker.
+      const int offset = ExitFrameConstants::kMarkerOffset;
+      ldc1(reg, MemOperand(fp,
+          (i - FPURegister::kNumRegisters) * kDoubleSize + offset));
+    }
+  }
+
   // Clear top frame.
-  LoadExternalReference(t0, ExternalReference(Isolate::k_c_entry_fp_address));
-  sw(zero_reg, MemOperand(t0));
+  li(t8, Operand(ExternalReference(Isolate::k_c_entry_fp_address, isolate())));
+  sw(zero_reg, MemOperand(t8));
 
   // Restore current context from top and clear it in debug mode.
-  LoadExternalReference(t0, ExternalReference(Isolate::k_context_address));
-  lw(cp, MemOperand(t0));
+  li(t8, Operand(ExternalReference(Isolate::k_context_address, isolate())));
+  lw(cp, MemOperand(t8));
 #ifdef DEBUG
-  sw(a3, MemOperand(t0));
+  sw(a3, MemOperand(t8));
 #endif
 
   // Pop the arguments, restore registers, and return.
   mov(sp, fp);  // Respect ABI stack constraint.
   lw(fp, MemOperand(sp, 0));
   lw(ra, MemOperand(sp, 4));
   lw(sp, MemOperand(sp, 8));
   jr(ra);
   nop();  // Branch delay slot nop.
 }
 
 
+void MacroAssembler::InitializeNewString(Register string,
+                                         Register length,
+                                         Heap::RootListIndex map_index,
+                                         Register scratch1,
+                                         Register scratch2) {
+  sll(scratch1, length, kSmiTagSize);
+  LoadRoot(scratch2, map_index);
+  sw(scratch1, FieldMemOperand(string, String::kLengthOffset));
+  li(scratch1, Operand(String::kEmptyHashField));
+  sw(scratch2, FieldMemOperand(string, HeapObject::kMapOffset));
+  sw(scratch1, FieldMemOperand(string, String::kHashFieldOffset));
+}
+
+
+int MacroAssembler::ActivationFrameAlignment() {
+#if defined(V8_HOST_ARCH_MIPS)
+  // Running on the real platform. Use the alignment as mandated by the local
+  // environment.
+  // Note: This will break if we ever start generating snapshots on one ARM
+  // platform for another ARM platform with a different alignment.
+  return OS::ActivationFrameAlignment();
+#else  // defined(V8_HOST_ARCH_MIPS)
+  // If we are using the simulator then we should always align to the expected
+  // alignment. As the simulator is used to generate snapshots we do not know
+  // if the target platform will need alignment, so this is controlled from a
+  // flag.
+  // return FLAG_sim_stack_alignment;  // TODO(REBASE): uncomment
+  return 2 * kPointerSize;  // TODO(REBASE): use above flog & remove this line.

[Søren Thygesen Gjesse, 2011/03/24 22:11:19]

REBASE -> mips, flog -> flag

[Paul Lind, 2011/03/26 18:39:17]

Deleted that line, and started using FLAG_sim_Stack_alignment.

+#endif  // defined(V8_HOST_ARCH_MIPS)
+}
+
+
 void MacroAssembler::AlignStack(int offset) {
   // On MIPS an offset of 0 aligns to 0 modulo 8 bytes,
   //     and an offset of 1 aligns to 4 modulo 8 bytes.
+#if defined(V8_HOST_ARCH_MIPS)
+  // Running on the real platform. Use the alignment as mandated by the local
+  // environment.
+  // Note: This will break if we ever start generating snapshots on one MIPS
+  // platform for another MIPS platform with a different alignment.
   int activation_frame_alignment = OS::ActivationFrameAlignment();
+#else  // defined(V8_HOST_ARCH_MIPS)
+  // If we are using the simulator then we should always align to the expected
+  // alignment. As the simulator is used to generate snapshots we do not know
+  // if the target platform will need alignment, so we will always align at
+  // this point here.
+  int activation_frame_alignment = 2 * kPointerSize;
+#endif  // defined(V8_HOST_ARCH_MIPS)
   if (activation_frame_alignment != kPointerSize) {
     // This code needs to be made more general if this assert doesn't hold.
     ASSERT(activation_frame_alignment == 2 * kPointerSize);
     if (offset == 0) {
-      andi(t0, sp, activation_frame_alignment - 1);
-      Push(zero_reg, eq, t0, zero_reg);
+      andi(t8, sp, activation_frame_alignment - 1);
+      Push(zero_reg, eq, t8, zero_reg);
     } else {
-      andi(t0, sp, activation_frame_alignment - 1);
-      addiu(t0, t0, -4);
-      Push(zero_reg, eq, t0, zero_reg);
+      andi(t8, sp, activation_frame_alignment - 1);
+      addiu(t8, t8, -4);
+      Push(zero_reg, eq, t8, zero_reg);
     }
   }
 }
 
+
+
+void MacroAssembler::JumpIfNotPowerOfTwoOrZero(
+    Register reg,
+    Register scratch,
+    Label* not_power_of_two_or_zero) {
+  Subu(scratch, reg, Operand(1));
+  Branch(not_power_of_two_or_zero, lt, scratch, Operand(zero_reg), false);
+  and_(at, scratch, reg);  // In the delay slot.
+  Branch(not_power_of_two_or_zero, ne, at, Operand(zero_reg));
+}
+
+
+void MacroAssembler::JumpIfNotBothSmi(Register reg1,
+                                      Register reg2,
+                                      Label* on_not_both_smi) {
+  STATIC_ASSERT(kSmiTag == 0);
+  ASSERT_EQ(1, kSmiTagMask);
+  or_(at, reg1, reg2);
+  andi(at, at, kSmiTagMask);
+  Branch(on_not_both_smi, ne, at, Operand(zero_reg));
+}
+
+
+void MacroAssembler::JumpIfEitherSmi(Register reg1,
+                                     Register reg2,
+                                     Label* on_either_smi) {
+  STATIC_ASSERT(kSmiTag == 0);
+  ASSERT_EQ(1, kSmiTagMask);
+  // Both Smi tags must be 1 (not Smi).
+  and_(at, reg1, reg2);
+  andi(at, at, kSmiTagMask);
+  Branch(on_either_smi, eq, at, Operand(zero_reg));
+}
+
+
+void MacroAssembler::AbortIfSmi(Register object) {
+  STATIC_ASSERT(kSmiTag == 0);
+  andi(at, object, kSmiTagMask);
+  Assert(ne, "Operand is a smi", at, Operand(zero_reg));
+}
+
+
+void MacroAssembler::AbortIfNotSmi(Register object) {
+  STATIC_ASSERT(kSmiTag == 0);
+  andi(at, object, kSmiTagMask);
+  Assert(eq, "Operand is a smi", at, Operand(zero_reg));
+}
+
+
+void MacroAssembler::AbortIfNotRootValue(Register src,
+                                         Heap::RootListIndex root_value_index,
+                                         const char* message) {
+  ASSERT(!src.is(at));
+  LoadRoot(at, root_value_index);
+  Assert(eq, message, src, Operand(at));
+}
+
+
+void MacroAssembler::JumpIfNotHeapNumber(Register object,
+                                         Register heap_number_map,
+                                         Register scratch,
+                                         Label* on_not_heap_number) {
+  lw(scratch, FieldMemOperand(object, HeapObject::kMapOffset));
+  AssertRegisterIsRoot(heap_number_map, Heap::kHeapNumberMapRootIndex);
+  Branch(on_not_heap_number, ne, scratch, Operand(heap_number_map));
+}
+
+
+void MacroAssembler::JumpIfNonSmisNotBothSequentialAsciiStrings(
+    Register first,
+    Register second,
+    Register scratch1,
+    Register scratch2,
+    Label* failure) {
+  // Test that both first and second are sequential ASCII strings.
+  // Assume that they are non-smis.
+  lw(scratch1, FieldMemOperand(first, HeapObject::kMapOffset));
+  lw(scratch2, FieldMemOperand(second, HeapObject::kMapOffset));
+  lbu(scratch1, FieldMemOperand(scratch1, Map::kInstanceTypeOffset));
+  lbu(scratch2, FieldMemOperand(scratch2, Map::kInstanceTypeOffset));
+
+  JumpIfBothInstanceTypesAreNotSequentialAscii(scratch1,
+                                               scratch2,
+                                               scratch1,
+                                               scratch2,
+                                               failure);
+}
+
+
+void MacroAssembler::JumpIfNotBothSequentialAsciiStrings(Register first,
+                                                         Register second,
+                                                         Register scratch1,
+                                                         Register scratch2,
+                                                         Label* failure) {
+  // Check that neither is a smi.
+  STATIC_ASSERT(kSmiTag == 0);
+  And(scratch1, first, Operand(second));
+  And(scratch1, scratch1, Operand(kSmiTagMask));
+  Branch(failure, eq, scratch1, Operand(zero_reg));
+  JumpIfNonSmisNotBothSequentialAsciiStrings(first,
+                                             second,
+                                             scratch1,
+                                             scratch2,
+                                             failure);
+}
+
+
+void MacroAssembler::JumpIfBothInstanceTypesAreNotSequentialAscii(
+    Register first,
+    Register second,
+    Register scratch1,
+    Register scratch2,
+    Label* failure) {
+  int kFlatAsciiStringMask =
+      kIsNotStringMask | kStringEncodingMask | kStringRepresentationMask;
+  int kFlatAsciiStringTag = ASCII_STRING_TYPE;
+  ASSERT(kFlatAsciiStringTag <= 0xffff);  // Ensure this fits 16-bit immed.
+  andi(scratch1, first, kFlatAsciiStringMask);
+  Branch(failure, ne, scratch1, Operand(kFlatAsciiStringTag));
+  andi(scratch2, second, kFlatAsciiStringMask);
+  Branch(failure, ne, scratch2, Operand(kFlatAsciiStringTag));
+}
+
+
+void MacroAssembler::JumpIfInstanceTypeIsNotSequentialAscii(Register type,
+                                                            Register scratch,
+                                                            Label* failure) {
+  int kFlatAsciiStringMask =
+      kIsNotStringMask | kStringEncodingMask | kStringRepresentationMask;
+  int kFlatAsciiStringTag = ASCII_STRING_TYPE;
+  And(scratch, type, Operand(kFlatAsciiStringMask));
+  Branch(failure, ne, scratch, Operand(kFlatAsciiStringTag));
+}
+
+
+static const int kRegisterPassedArguments = 4;
+
+void MacroAssembler::PrepareCallCFunction(int num_arguments, Register scratch) {
+  int frame_alignment = ActivationFrameAlignment();
+
+  // Reserve space for Isolate address which is always passed as last parameter
+  num_arguments += 1;
+
+  // Up to four simple arguments are passed in registers a0..a3.
+  // Those four arguments must have reserved argument slots on the stack for
+  // mips, even though those argument slots are not normally used.
+  // Remaining arguments are pushed on the stack, above (higher address than)
+  // the argument slots.
+  ASSERT(StandardFrameConstants::kCArgsSlotsSize % kPointerSize == 0);
+  int stack_passed_arguments = ((num_arguments <= kRegisterPassedArguments) ?
+                                 0 : num_arguments - kRegisterPassedArguments) +
+                               (StandardFrameConstants::kCArgsSlotsSize /
+                               kPointerSize);
+  if (frame_alignment > kPointerSize) {
+    // Make stack end at alignment and make room for num_arguments - 4 words
+    // and the original value of sp.
+    mov(scratch, sp);
+    Subu(sp, sp, Operand((stack_passed_arguments + 1) * kPointerSize));
+    ASSERT(IsPowerOf2(frame_alignment));
+    And(sp, sp, Operand(-frame_alignment));
+    sw(scratch, MemOperand(sp, stack_passed_arguments * kPointerSize));
+  } else {
+    Subu(sp, sp, Operand(stack_passed_arguments * kPointerSize));
+  }
+}
+
+
+void MacroAssembler::CallCFunction(ExternalReference function,
+                                   int num_arguments) {
+  CallCFunctionHelper(no_reg, function, at, num_arguments);
+}
+
+
+void MacroAssembler::CallCFunction(Register function,
+                                   Register scratch,
+                                   int num_arguments) {
+  CallCFunctionHelper(function,
+                      ExternalReference::the_hole_value_location(isolate()),
+                      scratch,
+                      num_arguments);
+}
+
+
+void MacroAssembler::CallCFunctionHelper(Register function,
+                                         ExternalReference function_reference,
+                                         Register scratch,
+                                         int num_arguments) {
+  // Push Isolate address as the last argument.
+  if (num_arguments < kRegisterPassedArguments) {
+    Register arg_to_reg[] = {a0, a1, a2, a3};
+    Register r = arg_to_reg[num_arguments];
+    li(r, Operand(ExternalReference::isolate_address()));
+  } else {
+    int stack_passed_arguments = num_arguments - kRegisterPassedArguments +
+                                 (StandardFrameConstants::kCArgsSlotsSize /
+                                  kPointerSize);
+    // Push Isolate address on the stack after the arguments.
+    li(scratch, Operand(ExternalReference::isolate_address()));
+    sw(scratch, MemOperand(sp, stack_passed_arguments * kPointerSize));
+  }
+  num_arguments += 1;
+
+  // Make sure that the stack is aligned before calling a C function unless
+  // running in the simulator. The simulator has its own alignment check which
+  // provides more information.
+  // The argument stots are presumed to have been set up by
+  // PrepareCallCFunction. The C function must be called via t9, for mips ABI.
+
+#if defined(V8_HOST_ARCH_MIPS)
+  if (emit_debug_code()) {
+    int frame_alignment = OS::ActivationFrameAlignment();
+    int frame_alignment_mask = frame_alignment - 1;
+    if (frame_alignment > kPointerSize) {
+      ASSERT(IsPowerOf2(frame_alignment));
+      Label alignment_as_expected;
+      And(at, sp, Operand(frame_alignment_mask));
+      Branch(&alignment_as_expected, eq, at, Operand(zero_reg));
+      // Don't use Check here, as it will call Runtime_Abort possibly
+      // re-entering here.
+      stop("Unexpected alignment in CallCFunction");
+      bind(&alignment_as_expected);
+    }
+  }
+#endif  // V8_HOST_ARCH_MIPS
+
+  // Just call directly. The function called cannot cause a GC, or
+  // allow preemption, so the return address in the link register
+  // stays correct.
+  if (!function.is(t9)) {
+    mov(t9, function);
+    function = t9;
+  }
+
+  if (function.is(no_reg)) {
+    li(t9, Operand(function_reference));
+    function = t9;
+  }
+
+  Call(function);
+
+  ASSERT(StandardFrameConstants::kCArgsSlotsSize % kPointerSize == 0);
+  int stack_passed_arguments = ((num_arguments <= kRegisterPassedArguments) ?
+                                0 : num_arguments - kRegisterPassedArguments) +
+                               (StandardFrameConstants::kCArgsSlotsSize /
+                               kPointerSize);
+
+  if (OS::ActivationFrameAlignment() > kPointerSize) {
+    lw(sp, MemOperand(sp, stack_passed_arguments * kPointerSize));
+  } else {
+    Addu(sp, sp, Operand(stack_passed_arguments * sizeof(kPointerSize)));
+  }
+}
+
+
+#undef BRANCH_ARGS_CHECK
+
+
+#ifdef ENABLE_DEBUGGER_SUPPORT
+CodePatcher::CodePatcher(byte* address, int instructions)
+    : address_(address),
+      instructions_(instructions),
+      size_(instructions * Assembler::kInstrSize),
+      masm_(address, size_ + Assembler::kGap) {
+  // Create a new macro assembler pointing to the address of the code to patch.
+  // The size is adjusted with kGap on order for the assembler to generate size
+  // bytes of instructions without failing with buffer size constraints.
+  ASSERT(masm_.reloc_info_writer.pos() == address_ + size_ + Assembler::kGap);
+}
+
+
+CodePatcher::~CodePatcher() {
+  // Indicate that code has changed.
+  CPU::FlushICache(address_, size_);
+
+  // Check that the code was patched as expected.
+  ASSERT(masm_.pc_ == address_ + size_);
+  ASSERT(masm_.reloc_info_writer.pos() == address_ + size_ + Assembler::kGap);
+}
+
+
+void CodePatcher::Emit(Instr x) {
+  masm()->emit(x);
+}
+
+
+void CodePatcher::Emit(Address addr) {
+  masm()->emit(reinterpret_cast<Instr>(addr));
+}
+
+
+#endif  // ENABLE_DEBUGGER_SUPPORT
+
+
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_MIPS