new style of property/function callbacks

src/ia32/macro-assembler-ia32.cc

 // 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 1936 matching lines @@
 // If false, it is returned as a pointer to a preallocated by caller memory
 // region. Pointer to this region should be passed to a function as an
 // implicit first argument.
 #if defined(USING_BSD_ABI) || defined(__MINGW32__) || defined(__CYGWIN__)
 static const bool kReturnHandlesDirectly = true;
 #else
 static const bool kReturnHandlesDirectly = false;
 #endif
 
 
-Operand ApiParameterOperand(int index) {
-  return Operand(
-      esp, (index + (kReturnHandlesDirectly ? 0 : 1)) * kPointerSize);
+Operand ApiParameterOperand(int index, bool returns_handle) {
+  int offset = (index +(kReturnHandlesDirectly || !returns_handle ? 0 : 1));
+  return Operand(esp, offset * kPointerSize);
 }
 
 
-void MacroAssembler::PrepareCallApiFunction(int argc) {
-  if (kReturnHandlesDirectly) {
+void MacroAssembler::PrepareCallApiFunction(int argc, bool returns_handle) {
+  if (kReturnHandlesDirectly || !returns_handle) {
     EnterApiExitFrame(argc);
     // When handles are returned directly we don't have to allocate extra
     // space for and pass an out parameter.
     if (emit_debug_code()) {
       mov(esi, Immediate(BitCast<int32_t>(kZapValue)));
     }
   } else {
     // We allocate two additional slots: return value and pointer to it.
     EnterApiExitFrame(argc + 2);
 
     // The argument slots are filled as follows:
     //
     //   n + 1: output slot
     //   n: arg n
     //   ...
     //   1: arg1
     //   0: pointer to the output slot
 
     lea(esi, Operand(esp, (argc + 1) * kPointerSize));
     mov(Operand(esp, 0 * kPointerSize), esi);
     if (emit_debug_code()) {
       mov(Operand(esi, 0), Immediate(0));
     }
   }
 }
 
 
 void MacroAssembler::CallApiFunctionAndReturn(Address function_address,
-                                              int stack_space) {
+                                              int stack_space,
+                                              bool returns_handle,
+                                              int return_value_offset) {
   ExternalReference next_address =
       ExternalReference::handle_scope_next_address(isolate());
   ExternalReference limit_address =
       ExternalReference::handle_scope_limit_address(isolate());
   ExternalReference level_address =
       ExternalReference::handle_scope_level_address(isolate());
 
   // Allocate HandleScope in callee-save registers.
   mov(ebx, Operand::StaticVariable(next_address));
   mov(edi, Operand::StaticVariable(limit_address));
@@ skipping 15 matching lines @@
   if (FLAG_log_timer_events) {
     FrameScope frame(this, StackFrame::MANUAL);
     PushSafepointRegisters();
     PrepareCallCFunction(1, eax);
     mov(Operand(esp, 0),
         Immediate(ExternalReference::isolate_address(isolate())));
     CallCFunction(ExternalReference::log_leave_external_function(isolate()), 1);
     PopSafepointRegisters();
   }
 
-  if (!kReturnHandlesDirectly) {
-    // PrepareCallApiFunction saved pointer to the output slot into
-    // callee-save register esi.
-    mov(eax, Operand(esi, 0));
+  Label prologue;
+  if (returns_handle) {
+    if (!kReturnHandlesDirectly) {
+      // PrepareCallApiFunction saved pointer to the output slot into
+      // callee-save register esi.
+      mov(eax, Operand(esi, 0));
+    }
+    Label empty_handle;
+    // Check if the result handle holds 0.
+    test(eax, eax);
+    j(zero, &empty_handle);
+    // It was non-zero.  Dereference to get the result value.
+    mov(eax, Operand(eax, 0));
+    jmp(&prologue);
+    bind(&empty_handle);
   }
+  // Load the value from ReturnValue
+  mov(eax, Operand(ebp, return_value_offset * kPointerSize));
 
-  Label empty_handle;
-  Label prologue;
   Label promote_scheduled_exception;
   Label delete_allocated_handles;
   Label leave_exit_frame;
 
-  // Check if the result handle holds 0.
-  test(eax, eax);
-  j(zero, &empty_handle);
-  // It was non-zero.  Dereference to get the result value.
-  mov(eax, Operand(eax, 0));
   bind(&prologue);
   // No more valid handles (the result handle was the last one). Restore
   // previous handle scope.
   mov(Operand::StaticVariable(next_address), ebx);
   sub(Operand::StaticVariable(level_address), Immediate(1));
   Assert(above_equal, "Invalid HandleScope level");
   cmp(edi, Operand::StaticVariable(limit_address));
   j(not_equal, &delete_allocated_handles);
   bind(&leave_exit_frame);
 
@@ skipping 35 matching lines @@
   j(equal, &ok, Label::kNear);
 
   Abort("API call returned invalid object");
 
   bind(&ok);
 #endif
 
   LeaveApiExitFrame();
   ret(stack_space * kPointerSize);
 
-  bind(&empty_handle);
-  // It was zero; the result is undefined.
-  mov(eax, isolate()->factory()->undefined_value());
-  jmp(&prologue);
-
   bind(&promote_scheduled_exception);
   TailCallRuntime(Runtime::kPromoteScheduledException, 0, 1);
 
   // HandleScope limit has changed. Delete allocated extensions.
   ExternalReference delete_extensions =
       ExternalReference::delete_handle_scope_extensions(isolate());
   bind(&delete_allocated_handles);
   mov(Operand::StaticVariable(limit_address), edi);
   mov(edi, eax);
   mov(Operand(esp, 0),
@@ skipping 1037 matching lines @@
   j(greater, &no_info_available);
   cmp(MemOperand(scratch_reg, -AllocationSiteInfo::kSize),
       Immediate(Handle<Map>(isolate()->heap()->allocation_site_info_map())));
   bind(&no_info_available);
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32