Push version 2.5.7 to trunk....

src/x64/code-stubs-x64.cc

Index: src/x64/code-stubs-x64.cc
===================================================================
--- src/x64/code-stubs-x64.cc	(revision 5846)
+++ src/x64/code-stubs-x64.cc	(working copy)
@@ -2483,20 +2483,6 @@
 }
 
 
-void ApiGetterEntryStub::Generate(MacroAssembler* masm) {
-  __ PrepareCallApiFunction(kStackSpace);
-#ifdef _WIN64
-  // All the parameters should be set up by a caller.
-#else
-  // Set 1st parameter register with property name.
-  __ movq(rsi, rdx);
-  // Second parameter register rdi should be set with pointer to AccessorInfo
-  // by a caller.
-#endif
-  __ CallApiFunctionAndReturn(fun());
-}
-
-
 void CEntryStub::GenerateCore(MacroAssembler* masm,
                               Label* throw_normal_exception,
                               Label* throw_termination_exception,
@@ -2549,18 +2535,18 @@
 #ifdef _WIN64
   // Windows 64-bit ABI passes arguments in rcx, rdx, r8, r9
   // Store Arguments object on stack, below the 4 WIN64 ABI parameter slots.
-  __ movq(Operand(rsp, 4 * kPointerSize), r14);  // argc.
-  __ movq(Operand(rsp, 5 * kPointerSize), r12);  // argv.
+  __ movq(StackSpaceOperand(0), r14);  // argc.
+  __ movq(StackSpaceOperand(1), r12);  // argv.
   if (result_size_ < 2) {
     // Pass a pointer to the Arguments object as the first argument.
     // Return result in single register (rax).
-    __ lea(rcx, Operand(rsp, 4 * kPointerSize));
+    __ lea(rcx, StackSpaceOperand(0));
   } else {
     ASSERT_EQ(2, result_size_);
     // Pass a pointer to the result location as the first argument.
-    __ lea(rcx, Operand(rsp, 6 * kPointerSize));
+    __ lea(rcx, StackSpaceOperand(2));
     // Pass a pointer to the Arguments object as the second argument.
-    __ lea(rdx, Operand(rsp, 4 * kPointerSize));
+    __ lea(rdx, StackSpaceOperand(0));
   }
 
 #else  // _WIN64
@@ -2596,7 +2582,7 @@
   __ j(zero, &failure_returned);
 
   // Exit the JavaScript to C++ exit frame.
-  __ LeaveExitFrame(result_size_);
+  __ LeaveExitFrame();
   __ ret(0);
 
   // Handling of failure.
@@ -2700,7 +2686,12 @@
   // builtin once.
 
   // Enter the exit frame that transitions from JavaScript to C++.
-  __ EnterExitFrame(result_size_);
+#ifdef _WIN64
+  int arg_stack_space = (result_size_ < 2 ? 2 : 4);
+#else
+  int arg_stack_space = 0;
+#endif
+  __ EnterExitFrame(arg_stack_space);
 
   // rax: Holds the context at this point, but should not be used.
   //      On entry to code generated by GenerateCore, it must hold