Lazily save double registers for HCallRuntime instructions within Hydrogen code stubs.

src/x64/lithium-x64.h

 // 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 254 matching lines @@
 
   void set_hydrogen_value(HValue* value) { hydrogen_value_ = value; }
   HValue* hydrogen_value() const { return hydrogen_value_; }
 
   void MarkAsCall() { bit_field_ = IsCallBits::update(bit_field_, true); }
   bool IsCall() const { return IsCallBits::decode(bit_field_); }
 
   // Interface to the register allocator and iterators.
   bool ClobbersTemps() const { return IsCall(); }
   bool ClobbersRegisters() const { return IsCall(); }
-  bool ClobbersDoubleRegisters() const { return IsCall(); }
+  virtual bool ClobbersDoubleRegisters() const { return IsCall(); }
 
   virtual void SetDeferredLazyDeoptimizationEnvironment(LEnvironment* env) { }
 
   // Interface to the register allocator and iterators.
   bool IsMarkedAsCall() const { return IsCall(); }
 
   virtual bool HasResult() const = 0;
   virtual LOperand* result() const = 0;
 
   LOperand* FirstInput() { return InputAt(0); }
@@ skipping 1626 matching lines @@
 
   int arity() const { return hydrogen()->argument_count() - 1; }
 };
 
 
 class LCallRuntime V8_FINAL : public LTemplateInstruction<1, 0, 0> {
  public:
   DECLARE_CONCRETE_INSTRUCTION(CallRuntime, "call-runtime")
   DECLARE_HYDROGEN_ACCESSOR(CallRuntime)
 
+  virtual bool ClobbersDoubleRegisters() const V8_OVERRIDE {
+    return save_doubles() == kDontSaveFPRegs;
+  }
+
   const Runtime::Function* function() const { return hydrogen()->function(); }
   int arity() const { return hydrogen()->argument_count(); }
+  SaveFPRegsMode save_doubles() const { return hydrogen()->save_doubles(); }
 };
 
 
 class LInteger32ToDouble V8_FINAL : public LTemplateInstruction<1, 1, 0> {
  public:
   explicit LInteger32ToDouble(LOperand* value) {
     inputs_[0] = value;
   }
 
   LOperand* value() { return inputs_[0]; }
@@ skipping 781 matching lines @@
 
   DISALLOW_COPY_AND_ASSIGN(LChunkBuilder);
 };
 
 #undef DECLARE_HYDROGEN_ACCESSOR
 #undef DECLARE_CONCRETE_INSTRUCTION
 
 } }  // namespace v8::int
 
 #endif  // V8_X64_LITHIUM_X64_H_