new style of property/function callbacks

src/x64/stub-cache-x64.cc

Index: src/x64/stub-cache-x64.cc
diff --git a/src/x64/stub-cache-x64.cc b/src/x64/stub-cache-x64.cc
index f0b362b947d046184bfd592ee381b9a938933394..a1e916866123da156710646ecdc75b262f54efe0 100644
--- a/src/x64/stub-cache-x64.cc
+++ b/src/x64/stub-cache-x64.cc
@@ -398,7 +398,7 @@ static void CompileCallLoadPropertyWithInterceptor(
 
 
 // Number of pointers to be reserved on stack for fast API call.
-static const int kFastApiCallArguments = 4;
+static const int kFastApiCallArguments = FunctionCallbackArguments::kArgsLength;
 
 
 // Reserves space for the extra arguments to API function in the
@@ -449,10 +449,12 @@ static void GenerateFastApiCall(MacroAssembler* masm,
   //                           (first fast api call extra argument)
   //  -- rsp[24]             : api call data
   //  -- rsp[32]             : isolate
-  //  -- rsp[40]             : last argument
+  //  -- rsp[40]             : ReturnValue
+  //
+  //  -- rsp[48]             : last argument
   //  -- ...
-  //  -- rsp[(argc + 4) * 8] : first argument
-  //  -- rsp[(argc + 5) * 8] : receiver
+  //  -- rsp[(argc + 5) * 8] : first argument
+  //  -- rsp[(argc + 6) * 8] : receiver
   // -----------------------------------
   // Get the function and setup the context.
   Handle<JSFunction> function = optimization.constant_function();
@@ -473,9 +475,12 @@ static void GenerateFastApiCall(MacroAssembler* masm,
   __ movq(kScratchRegister,
           ExternalReference::isolate_address(masm->isolate()));
   __ movq(Operand(rsp, 4 * kPointerSize), kScratchRegister);
+  __ LoadRoot(kScratchRegister, Heap::kUndefinedValueRootIndex);
+  __ movq(Operand(rsp, 5 * kPointerSize), kScratchRegister);
 
   // Prepare arguments.
-  __ lea(rbx, Operand(rsp, 4 * kPointerSize));
+  STATIC_ASSERT(kFastApiCallArguments == 5);
+  __ lea(rbx, Operand(rsp, kFastApiCallArguments * kPointerSize));
 
 #if defined(__MINGW64__)
   Register arguments_arg = rcx;
@@ -505,7 +510,8 @@ static void GenerateFastApiCall(MacroAssembler* masm,
   // Function address is a foreign pointer outside V8's heap.
   Address function_address = v8::ToCData<Address>(api_call_info->callback());
   __ CallApiFunctionAndReturn(function_address,
-                              argc + kFastApiCallArguments + 1);
+                              argc + kFastApiCallArguments + 1,
+                              FunctionCallbackArguments::kReturnValueOffset);
 }
 
 
@@ -1288,7 +1294,9 @@ void BaseLoadStubCompiler::GenerateLoadCallback(
   } else {
     __ Push(Handle<Object>(callback->data(), isolate()));
   }
-  __ PushAddress(ExternalReference::isolate_address(isolate()));  // isolate
+  __ PushAddress(ExternalReference::isolate_address(isolate()));
+  __ LoadRoot(kScratchRegister, Heap::kUndefinedValueRootIndex);
+  __ push(kScratchRegister);  // return value
   __ push(name());  // name
   // Save a pointer to where we pushed the arguments pointer.  This will be
   // passed as the const ExecutableAccessorInfo& to the C++ callback.
@@ -1309,14 +1317,15 @@ void BaseLoadStubCompiler::GenerateLoadCallback(
   __ movq(name_arg, rsp);
   __ push(scratch2());  // Restore return address.
 
-  // 4 elements array for v8::Arguments::values_ and handler for name.
-  const int kStackSpace = 5;
+  // v8::Arguments::values_ and handler for name.
+  const int kStackSpace = PropertyCallbackArguments::kArgsLength + 1;
 
   // Allocate v8::AccessorInfo in non-GCed stack space.
   const int kArgStackSpace = 1;
 
   __ PrepareCallApiFunction(kArgStackSpace);
-  __ lea(rax, Operand(name_arg, 4 * kPointerSize));
+  STATIC_ASSERT(PropertyCallbackArguments::kArgsLength == 5);
+  __ lea(rax, Operand(name_arg, 5 * kPointerSize));
 
   // v8::AccessorInfo::args_.
   __ movq(StackSpaceOperand(0), rax);
@@ -1326,7 +1335,9 @@ void BaseLoadStubCompiler::GenerateLoadCallback(
   __ lea(accessor_info_arg, StackSpaceOperand(0));
 
   Address getter_address = v8::ToCData<Address>(callback->getter());
-  __ CallApiFunctionAndReturn(getter_address, kStackSpace);
+  __ CallApiFunctionAndReturn(getter_address,
+                              kStackSpace,
+                              PropertyCallbackArguments::kReturnValueOffset);
 }
 
 
@@ -2272,7 +2283,7 @@ Handle<Code> CallStubCompiler::CompileFastApiCall(
                   name, depth, &miss);
 
   // Move the return address on top of the stack.
-  __ movq(rax, Operand(rsp, 4 * kPointerSize));
+  __ movq(rax, Operand(rsp, kFastApiCallArguments * kPointerSize));
   __ movq(Operand(rsp, 0 * kPointerSize), rax);
 
   GenerateFastApiCall(masm(), optimization, argc);