[x64] Make xmm0 allocatable and use xmm15 as scratch register instead.

src/x64/macro-assembler-x64.cc

 // Copyright 2012 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/base/bits.h"
 #include "src/base/division-by-constant.h"
 #include "src/bootstrapper.h"
 #include "src/codegen.h"
@@ skipping 3241 matching lines @@
   shrq(dst, Immediate(32));
 }
 
 
 void MacroAssembler::Pinsrd(XMMRegister dst, Register src, int8_t imm8) {
   if (CpuFeatures::IsSupported(SSE4_1)) {
     CpuFeatureScope sse_scope(this, SSE4_1);
     pinsrd(dst, src, imm8);
     return;
   }
-  Movd(xmm0, src);
+  Movd(kScratchDoubleReg, src);
   if (imm8 == 1) {
-    punpckldq(dst, xmm0);
+    punpckldq(dst, kScratchDoubleReg);
   } else {
     DCHECK_EQ(0, imm8);
-    Movss(dst, xmm0);
+    Movss(dst, kScratchDoubleReg);
   }
 }
 
 
 void MacroAssembler::Pinsrd(XMMRegister dst, const Operand& src, int8_t imm8) {
   DCHECK(imm8 == 0 || imm8 == 1);
   if (CpuFeatures::IsSupported(SSE4_1)) {
     CpuFeatureScope sse_scope(this, SSE4_1);
     pinsrd(dst, src, imm8);
     return;
   }
-  Movd(xmm0, src);
+  Movd(kScratchDoubleReg, src);
   if (imm8 == 1) {
-    punpckldq(dst, xmm0);
+    punpckldq(dst, kScratchDoubleReg);
   } else {
     DCHECK_EQ(0, imm8);
-    Movss(dst, xmm0);
+    Movss(dst, kScratchDoubleReg);
   }
 }
 
 
 void MacroAssembler::Lzcntl(Register dst, Register src) {
   if (CpuFeatures::IsSupported(LZCNT)) {
     CpuFeatureScope scope(this, LZCNT);
     lzcntl(dst, src);
     return;
   }
@@ skipping 441 matching lines @@
                                      Register input_reg,
                                      int offset) {
   DoubleToIStub stub(isolate(), input_reg, result_reg, offset, true);
   call(stub.GetCode(), RelocInfo::CODE_TARGET);
 }
 
 
 void MacroAssembler::TruncateHeapNumberToI(Register result_reg,
                                            Register input_reg) {
   Label done;
-  Movsd(xmm0, FieldOperand(input_reg, HeapNumber::kValueOffset));
-  Cvttsd2siq(result_reg, xmm0);
+  Movsd(kScratchDoubleReg, FieldOperand(input_reg, HeapNumber::kValueOffset));
+  Cvttsd2siq(result_reg, kScratchDoubleReg);
   cmpq(result_reg, Immediate(1));
   j(no_overflow, &done, Label::kNear);
 
   // Slow case.
   if (input_reg.is(result_reg)) {
     subp(rsp, Immediate(kDoubleSize));
-    Movsd(MemOperand(rsp, 0), xmm0);
+    Movsd(MemOperand(rsp, 0), kScratchDoubleReg);
     SlowTruncateToI(result_reg, rsp, 0);
     addp(rsp, Immediate(kDoubleSize));
   } else {
     SlowTruncateToI(result_reg, input_reg);
   }
 
   bind(&done);
   // Keep our invariant that the upper 32 bits are zero.
   movl(result_reg, result_reg);
 }
@@ skipping 16 matching lines @@
   movl(result_reg, result_reg);
 }
 
 
 void MacroAssembler::DoubleToI(Register result_reg, XMMRegister input_reg,
                                XMMRegister scratch,
                                MinusZeroMode minus_zero_mode,
                                Label* lost_precision, Label* is_nan,
                                Label* minus_zero, Label::Distance dst) {
   Cvttsd2si(result_reg, input_reg);
-  Cvtlsi2sd(xmm0, result_reg);
-  Ucomisd(xmm0, input_reg);
+  Cvtlsi2sd(kScratchDoubleReg, result_reg);
+  Ucomisd(kScratchDoubleReg, input_reg);
   j(not_equal, lost_precision, dst);
   j(parity_even, is_nan, dst);  // NaN.
   if (minus_zero_mode == FAIL_ON_MINUS_ZERO) {
     Label done;
     // The integer converted back is equal to the original. We
     // only have to test if we got -0 as an input.
     testl(result_reg, result_reg);
     j(not_zero, &done, Label::kNear);
     Movmskpd(result_reg, input_reg);
     // Bit 0 contains the sign of the double in input_reg.
@@ skipping 1918 matching lines @@
   movl(rax, dividend);
   shrl(rax, Immediate(31));
   addl(rdx, rax);
 }
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_X64