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

src/x64/macro-assembler-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 1231 matching lines @@
   // Call a code stub.
   void CallStub(CodeStub* stub, TypeFeedbackId ast_id = TypeFeedbackId::None());
 
   // Tail call a code stub (jump).
   void TailCallStub(CodeStub* stub);
 
   // Return from a code stub after popping its arguments.
   void StubReturn(int argc);
 
   // Call a runtime routine.
-  void CallRuntime(const Runtime::Function* f, int num_arguments);
+  void CallRuntime(const Runtime::Function* f,
+                   int num_arguments,
+                   SaveFPRegsMode save_doubles = kDontSaveFPRegs);
 
   // Call a runtime function and save the value of XMM registers.
-  void CallRuntimeSaveDoubles(Runtime::FunctionId id);
+  void CallRuntimeSaveDoubles(Runtime::FunctionId id) {
+    const Runtime::Function* function = Runtime::FunctionForId(id);
+    CallRuntime(function, function->nargs, kSaveFPRegs);
+  }
 
   // Convenience function: Same as above, but takes the fid instead.
-  void CallRuntime(Runtime::FunctionId id, int num_arguments);
+  void CallRuntime(Runtime::FunctionId id, int num_arguments) {
+    CallRuntime(Runtime::FunctionForId(id), num_arguments);
+  }
 
   // Convenience function: call an external reference.
   void CallExternalReference(const ExternalReference& ext,
                              int num_arguments);
 
   // Tail call of a runtime routine (jump).
   // Like JumpToExternalReference, but also takes care of passing the number
   // of parameters.
   void TailCallExternalReference(const ExternalReference& ext,
                                  int num_arguments,
@@ skipping 313 matching lines @@
     masm->popfq();                                                           \
   }                                                                          \
   masm->
 #else
 #define ACCESS_MASM(masm) masm->
 #endif
 
 } }  // namespace v8::internal
 
 #endif  // V8_X64_MACRO_ASSEMBLER_X64_H_