[intrinsics] Kill the %_IsMinusZero intrinsic.

src/crankshaft/x64/lithium-codegen-x64.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #if V8_TARGET_ARCH_X64
 
 #include "src/crankshaft/x64/lithium-codegen-x64.h"
 
 #include "src/base/bits.h"
 #include "src/code-factory.h"
@@ skipping 2265 matching lines @@
   __ subp(rsp, Immediate(kDoubleSize));
   __ Movsd(MemOperand(rsp, 0), input_reg);
   __ addp(rsp, Immediate(kDoubleSize));
 
   int offset = sizeof(kHoleNanUpper32);
   __ cmpl(MemOperand(rsp, -offset), Immediate(kHoleNanUpper32));
   EmitBranch(instr, equal);
 }
 
 
-void LCodeGen::DoCompareMinusZeroAndBranch(LCompareMinusZeroAndBranch* instr) {
-  Representation rep = instr->hydrogen()->value()->representation();
-  DCHECK(!rep.IsInteger32());
-
-  if (rep.IsDouble()) {
-    XMMRegister value = ToDoubleRegister(instr->value());
-    XMMRegister xmm_scratch = double_scratch0();
-    __ Xorpd(xmm_scratch, xmm_scratch);
-    __ Ucomisd(xmm_scratch, value);
-    EmitFalseBranch(instr, not_equal);
-    __ Movmskpd(kScratchRegister, value);
-    __ testl(kScratchRegister, Immediate(1));
-    EmitBranch(instr, not_zero);
-  } else {
-    Register value = ToRegister(instr->value());
-    Handle<Map> map = masm()->isolate()->factory()->heap_number_map();
-    __ CheckMap(value, map, instr->FalseLabel(chunk()), DO_SMI_CHECK);
-    __ cmpl(FieldOperand(value, HeapNumber::kExponentOffset),
-            Immediate(0x1));
-    EmitFalseBranch(instr, no_overflow);
-    __ cmpl(FieldOperand(value, HeapNumber::kMantissaOffset),
-            Immediate(0x00000000));
-    EmitBranch(instr, equal);
-  }
-}
-
-
 Condition LCodeGen::EmitIsString(Register input,
                                  Register temp1,
                                  Label* is_not_string,
                                  SmiCheck check_needed = INLINE_SMI_CHECK) {
   if (check_needed == INLINE_SMI_CHECK) {
     __ JumpIfSmi(input, is_not_string);
   }
 
   Condition cond =  masm_->IsObjectStringType(input, temp1, temp1);
 
@@ skipping 3323 matching lines @@
   RecordSafepoint(Safepoint::kNoLazyDeopt);
 }
 
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_X64