[builtins] Introduce proper Float64Tan operator.

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 5078 matching lines @@
   Register result_reg = ToRegister(instr->result());
   if (instr->hydrogen()->bits() == HDoubleBits::HIGH) {
     __ Movq(result_reg, value_reg);
     __ shrq(result_reg, Immediate(32));
   } else {
     __ Movd(result_reg, value_reg);
   }
 }
 
 
-void LCodeGen::DoConstructDouble(LConstructDouble* instr) {
-  Register hi_reg = ToRegister(instr->hi());
-  Register lo_reg = ToRegister(instr->lo());
-  XMMRegister result_reg = ToDoubleRegister(instr->result());
-  __ movl(kScratchRegister, hi_reg);
-  __ shlq(kScratchRegister, Immediate(32));
-  __ orq(kScratchRegister, lo_reg);
-  __ Movq(result_reg, kScratchRegister);
-}
-
-
 void LCodeGen::DoAllocate(LAllocate* instr) {
   class DeferredAllocate final : public LDeferredCode {
    public:
     DeferredAllocate(LCodeGen* codegen, LAllocate* instr)
         : LDeferredCode(codegen), instr_(instr) { }
     void Generate() override { codegen()->DoDeferredAllocate(instr_); }
     LInstruction* instr() override { return instr_; }
 
    private:
     LAllocate* instr_;
@@ skipping 481 matching lines @@
   __ bind(deferred->exit());
   __ bind(&done);
 }
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_X64