Introduce intrinsics for double values in Javascript.

src/x64/lithium-x64.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1830 matching lines @@
     ASSERT(input_rep.IsSmiOrTagged());
     // Register allocator doesn't (yet) support allocation of double
     // temps. Reserve xmm1 explicitly.
     LClampTToUint8* result = new(zone()) LClampTToUint8(reg,
                                                         FixedTemp(xmm1));
     return AssignEnvironment(DefineSameAsFirst(result));
   }
 }
 
 
+LInstruction* LChunkBuilder::DoDoubleBits(HDoubleBits* instr) {
+  HValue* value = instr->value();
+  ASSERT(value->representation().IsDouble());
+  return DefineAsRegister(new(zone()) LDoubleBits(UseRegister(value)));
+}
+
+
+LInstruction* LChunkBuilder::DoConstructDouble(HConstructDouble* instr) {
+  LOperand* lo = UseRegister(instr->lo());
+  LOperand* hi = UseRegister(instr->hi());
+  return DefineAsRegister(new(zone()) LConstructDouble(hi, lo));
+}
+
+
 LInstruction* LChunkBuilder::DoReturn(HReturn* instr) {
   LOperand* context = info()->IsStub() ? UseFixed(instr->context(), rsi) : NULL;
   LOperand* parameter_count = UseRegisterOrConstant(instr->parameter_count());
   return new(zone()) LReturn(
       UseFixed(instr->value(), rax), context, parameter_count);
 }
 
 
 LInstruction* LChunkBuilder::DoConstant(HConstant* instr) {
   Representation r = instr->representation();
@@ skipping 574 matching lines @@
 LInstruction* LChunkBuilder::DoLoadFieldByIndex(HLoadFieldByIndex* instr) {
   LOperand* object = UseRegister(instr->object());
   LOperand* index = UseTempRegister(instr->index());
   return DefineSameAsFirst(new(zone()) LLoadFieldByIndex(object, index));
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64