Optimize %IsConstructCall() on IA-32.

src/ia32/codegen-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 4969 matching lines @@
   Result temp = allocator()->Allocate();
   ASSERT(temp.is_valid());
   // Check if the object is a JS array or not.
   __ CmpObjectType(value.reg(), JS_ARRAY_TYPE, temp.reg());
   value.Unuse();
   temp.Unuse();
   destination()->Split(equal);
 }
 
 
+void CodeGenerator::GenerateIsConstructCall(ZoneList<Expression*>* args) {
+  ASSERT(args->length() == 0);
+
+  // Get the frame pointer for the calling frame.
+  Result fp = allocator()->Allocate();
+  __ mov(fp.reg(), Operand(ebp, StandardFrameConstants::kCallerFPOffset));
+
+  // Skip the arguments adaptor frame if it exists.
+  Label check_frame_marker;
+  __ cmp(Operand(fp.reg(), StandardFrameConstants::kContextOffset),
+         Immediate(ArgumentsAdaptorFrame::SENTINEL));
+  __ j(not_equal, &check_frame_marker);
+  __ mov(fp.reg(), Operand(fp.reg(), StandardFrameConstants::kCallerFPOffset));
+
+  // Check the marker in the calling frame.
+  __ bind(&check_frame_marker);
+  __ cmp(Operand(fp.reg(), StandardFrameConstants::kMarkerOffset),
+         Immediate(Smi::FromInt(StackFrame::CONSTRUCT)));
+  fp.Unuse();
+  destination()->Split(equal);
+}
+
+
 void CodeGenerator::GenerateArgumentsLength(ZoneList<Expression*>* args) {
   ASSERT(args->length() == 0);
   // ArgumentsAccessStub takes the parameter count as an input argument
   // in register eax.  Create a constant result for it.
   Result count(Handle<Smi>(Smi::FromInt(scope_->num_parameters())));
   // Call the shared stub to get to the arguments.length.
   ArgumentsAccessStub stub(ArgumentsAccessStub::READ_LENGTH);
   Result result = frame_->CallStub(&stub, &count);
   frame_->Push(&result);
 }
@@ skipping 2852 matching lines @@
 
   // Slow-case: Go through the JavaScript implementation.
   __ bind(&slow);
   __ InvokeBuiltin(Builtins::INSTANCE_OF, JUMP_FUNCTION);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal