API call code refactoring (ia32).

src/ia32/macro-assembler-ia32.cc

 // Copyright 2006-2009 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 374 matching lines @@
 
   // Setup argc and argv in callee-saved registers.
   int offset = StandardFrameConstants::kCallerSPOffset - kPointerSize;
   mov(edi, Operand(eax));
   lea(esi, Operand(ebp, eax, times_4, offset));
 
   EnterExitFrameEpilogue(2);
 }
 
 
-void MacroAssembler::EnterApiExitFrame(int stack_space,
-                                       int argc) {
+void MacroAssembler::EnterApiExitFrame(int argc) {
   EnterExitFramePrologue();
-
-  int offset = StandardFrameConstants::kCallerSPOffset - kPointerSize;
-  lea(esi, Operand(ebp, (stack_space * kPointerSize) + offset));
-
   EnterExitFrameEpilogue(argc);
 }
 
 
 void MacroAssembler::LeaveExitFrame() {
   // Get the return address from the stack and restore the frame pointer.
   mov(ecx, Operand(ebp, 1 * kPointerSize));
   mov(ebp, Operand(ebp, 0 * kPointerSize));
 
   // Pop the arguments and the receiver from the caller stack.
   lea(esp, Operand(esi, 1 * kPointerSize));
 
   // Restore current context from top and clear it in debug mode.
   ExternalReference context_address(Top::k_context_address);
   mov(esi, Operand::StaticVariable(context_address));
 #ifdef DEBUG
   mov(Operand::StaticVariable(context_address), Immediate(0));
 #endif
 
   // Push the return address to get ready to return.
   push(ecx);
 
   // Clear the top frame.
   ExternalReference c_entry_fp_address(Top::k_c_entry_fp_address);
   mov(Operand::StaticVariable(c_entry_fp_address), Immediate(0));
 }
 
 
+void MacroAssembler::LeaveApiExitFrame() {
+  mov(esp, Operand(ebp));
+  pop(ebp);
+
+  // Restore current context from top and clear it in debug mode.

[antonm, 2010/11/16 14:32:26]

I'd suggest (but not insisting) to factor out common exit frame management. 
Should be simple if push(ecx) is moved out of common code.

[SeRya, 2010/11/16 14:53:28]

Done.

+  ExternalReference context_address(Top::k_context_address);
+  mov(esi, Operand::StaticVariable(context_address));
+#ifdef DEBUG
+  mov(Operand::StaticVariable(context_address), Immediate(0));
+#endif
+
+  // Clear the top frame.
+  ExternalReference c_entry_fp_address(Top::k_c_entry_fp_address);
+  mov(Operand::StaticVariable(c_entry_fp_address), Immediate(0));
+}
+
+
 void MacroAssembler::PushTryHandler(CodeLocation try_location,
                                     HandlerType type) {
   // Adjust this code if not the case.
   ASSERT(StackHandlerConstants::kSize == 4 * kPointerSize);
   // The pc (return address) is already on TOS.
   if (try_location == IN_JAVASCRIPT) {
     if (type == TRY_CATCH_HANDLER) {
       push(Immediate(StackHandler::TRY_CATCH));
     } else {
       push(Immediate(StackHandler::TRY_FINALLY));
@@ skipping 704 matching lines @@
 #else
 static const bool kPassHandlesDirectly = false;
 #endif
 
 
 Operand ApiParameterOperand(int index) {
   return Operand(esp, (index + (kPassHandlesDirectly ? 0 : 1)) * kPointerSize);
 }
 
 
-void MacroAssembler::PrepareCallApiFunction(int stack_space, int argc) {
+void MacroAssembler::PrepareCallApiFunction(int argc, Register scratch) {
   if (kPassHandlesDirectly) {
-    EnterApiExitFrame(stack_space, argc);
+    EnterApiExitFrame(argc);
     // When handles as passed directly we don't have to allocate extra
     // space for and pass an out parameter.
   } else {
     // We allocate two additional slots: return value and pointer to it.
-    EnterApiExitFrame(stack_space, argc + 2);
-  }
-}
+    EnterApiExitFrame(argc + 2);
 
-
-MaybeObject* MacroAssembler::TryCallApiFunctionAndReturn(ApiFunction* function,
-                                                         int argc) {
-  if (!kPassHandlesDirectly) {
     // The argument slots are filled as follows:
     //
     //   n + 1: output cell
     //   n: arg n
     //   ...
     //   1: arg1
     //   0: pointer to the output cell
     //
     // Note that this is one more "argument" than the function expects
     // so the out cell will have to be popped explicitly after returning
     // from the function. The out cell contains Handle.
-    lea(eax, Operand(esp, (argc + 1) * kPointerSize));  // pointer to out cell.
-    mov(Operand(esp, 0 * kPointerSize), eax);  // output.
-    mov(Operand(esp, (argc + 1) * kPointerSize), Immediate(0));  // out cell.
+
+    // pointer to out cell.
+    lea(scratch, Operand(esp, (argc + 1) * kPointerSize));
+    mov(Operand(esp, 0 * kPointerSize), scratch);  // output.
+    if (FLAG_debug_code) {
+      mov(Operand(esp, (argc + 1) * kPointerSize), Immediate(0));  // out cell.
+    }
   }
+}
 
+
+MaybeObject* MacroAssembler::TryCallApiFunctionAndReturn(ApiFunction* function,
+                                                         int stack_space) {
   ExternalReference next_address =
       ExternalReference::handle_scope_next_address();
   ExternalReference limit_address =
       ExternalReference::handle_scope_limit_address();
   ExternalReference level_address =
       ExternalReference::handle_scope_level_address();
 
   // Allocate HandleScope in callee-save registers.
   mov(ebx, Operand::StaticVariable(next_address));
   mov(edi, Operand::StaticVariable(limit_address));
@@ skipping 28 matching lines @@
   cmp(edi, Operand::StaticVariable(limit_address));
   j(not_equal, &delete_allocated_handles, not_taken);
   bind(&leave_exit_frame);
 
   // Check if the function scheduled an exception.
   ExternalReference scheduled_exception_address =
       ExternalReference::scheduled_exception_address();
   cmp(Operand::StaticVariable(scheduled_exception_address),
          Immediate(Factory::the_hole_value()));
   j(not_equal, &promote_scheduled_exception, not_taken);
-  LeaveExitFrame();
-  ret(0);
+  LeaveApiExitFrame();
+  ret(stack_space * kPointerSize);
   bind(&promote_scheduled_exception);
   MaybeObject* result =
       TryTailCallRuntime(Runtime::kPromoteScheduledException, 0, 1);
   if (result->IsFailure()) {
     return result;
   }
   bind(&empty_handle);
   // It was zero; the result is undefined.
   mov(eax, Factory::undefined_value());
   jmp(&prologue);
@@ skipping 554 matching lines @@
 
   // Check that the code was patched as expected.
   ASSERT(masm_.pc_ == address_ + size_);
   ASSERT(masm_.reloc_info_writer.pos() == address_ + size_ + Assembler::kGap);
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32