X64: Adding macro to load double from memory, and use SSE3 instruction if present.

src/x64/lithium-codegen-x64.cc

Index: src/x64/lithium-codegen-x64.cc
diff --git a/src/x64/lithium-codegen-x64.cc b/src/x64/lithium-codegen-x64.cc
index 688a557ee8710819abb682b569a939f45819b4cc..4f3eed3b7b8c6b584228530d067659b6b058c1d9 100644
--- a/src/x64/lithium-codegen-x64.cc
+++ b/src/x64/lithium-codegen-x64.cc
@@ -2833,7 +2833,7 @@ void LCodeGen::DoPower(LPower* instr) {
     __ bind(&non_smi);
     __ CmpObjectType(right_reg, HEAP_NUMBER_TYPE , kScratchRegister);
     DeoptimizeIf(not_equal, instr->environment());
-    __ movsd(xmm1, FieldOperand(right_reg, HeapNumber::kValueOffset));
+    __ LoadDbl(xmm1, FieldOperand(right_reg, HeapNumber::kValueOffset));
 
     __ bind(&call);
     __ PrepareCallCFunction(2);
@@ -3436,7 +3436,7 @@ void LCodeGen::EmitNumberUntagD(Register input_reg,
 
   // Heap number to XMM conversion.
   __ bind(&heap_number);
-  __ movsd(result_reg, FieldOperand(input_reg, HeapNumber::kValueOffset));
+  __ LoadDbl(result_reg, FieldOperand(input_reg, HeapNumber::kValueOffset));
   __ jmp(&done);
 
   // Smi to XMM conversion
@@ -3476,7 +3476,7 @@ void LCodeGen::DoDeferredTaggedToI(LTaggedToI* instr) {
 
     __ bind(&heap_number);
 
-    __ movsd(xmm0, FieldOperand(input_reg, HeapNumber::kValueOffset));
+    __ LoadDbl(xmm0, FieldOperand(input_reg, HeapNumber::kValueOffset));
     __ cvttsd2siq(input_reg, xmm0);
     __ Set(kScratchRegister, V8_UINT64_C(0x8000000000000000));
     __ cmpq(input_reg, kScratchRegister);
@@ -3486,7 +3486,7 @@ void LCodeGen::DoDeferredTaggedToI(LTaggedToI* instr) {
     DeoptimizeIf(not_equal, instr->environment());
 
     XMMRegister xmm_temp = ToDoubleRegister(instr->TempAt(0));
-    __ movsd(xmm0, FieldOperand(input_reg, HeapNumber::kValueOffset));
+    __ LoadDbl(xmm0, FieldOperand(input_reg, HeapNumber::kValueOffset));
     __ cvttsd2si(input_reg, xmm0);
     __ cvtlsi2sd(xmm_temp, input_reg);
     __ ucomisd(xmm0, xmm_temp);