Make the ResolvePossiblyDirectEval faster by avoiding the...

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 4562 matching lines @@
     }
 
     // Prepare the stack for the call to ResolvePossiblyDirectEval.
     frame_->PushElementAt(arg_count + 1);
     if (arg_count > 0) {
       frame_->PushElementAt(arg_count);
     } else {
       frame_->Push(Factory::undefined_value());
     }
 
+    // Push the receiver.
+    frame_->PushParameterAt(-1);
+
     // Resolve the call.
     Result result =
-        frame_->CallRuntime(Runtime::kResolvePossiblyDirectEval, 2);
+        frame_->CallRuntime(Runtime::kResolvePossiblyDirectEval, 3);
 
-    // Touch up the stack with the right values for the function and the
-    // receiver.  Use a scratch register to avoid destroying the result.
-    Result scratch = allocator_->Allocate();
-    ASSERT(scratch.is_valid());
-    __ mov(scratch.reg(), FieldOperand(result.reg(), FixedArray::kHeaderSize));
-    frame_->SetElementAt(arg_count + 1, &scratch);
-
-    // We can reuse the result register now.
-    frame_->Spill(result.reg());
-    __ mov(result.reg(),
-           FieldOperand(result.reg(), FixedArray::kHeaderSize + kPointerSize));
-    frame_->SetElementAt(arg_count, &result);
+    // The runtime call returns a pair of values in eax (function) and
+    // edx (receiver). Touch up the stack with the right values.
+    Result receiver = allocator_->Allocate(edx);
+    frame_->SetElementAt(arg_count + 1, &result);
+    frame_->SetElementAt(arg_count, &receiver);
+    receiver.Unuse();
 
     // Call the function.
     CodeForSourcePosition(node->position());
     InLoopFlag in_loop = loop_nesting() > 0 ? IN_LOOP : NOT_IN_LOOP;
     CallFunctionStub call_function(arg_count, in_loop);
     result = frame_->CallStub(&call_function, arg_count + 1);
 
     // Restore the context and overwrite the function on the stack with
     // the result.
     frame_->RestoreContextRegister();
@@ skipping 4291 matching lines @@
     __ add(Operand(dest), Immediate(2));
   }
   __ sub(Operand(count), Immediate(1));
   __ j(not_zero, &loop);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal