One less dependent load in InvokeBuiltin.

src/x64/macro-assembler-x64.cc

 // Copyright 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 427 matching lines @@
   // Rely on the assertion to check that the number of provided
   // arguments match the expected number of arguments. Fake a
   // parameter count to avoid emitting code to do the check.
   ParameterCount expected(0);
   GetBuiltinEntry(rdx, id);
   InvokeCode(rdx, expected, expected, flag);
 }
 
 
 void MacroAssembler::GetBuiltinEntry(Register target, Builtins::JavaScript id) {
+  ASSERT(!target.is(rdi));
+
+  // Load the builtins object into target register.
+  movq(target, Operand(rsi, Context::SlotOffset(Context::GLOBAL_INDEX)));
+  movq(target, FieldOperand(target, GlobalObject::kBuiltinsOffset));
+
   // Load the JavaScript builtin function from the builtins object.
-  movq(rdi, Operand(rsi, Context::SlotOffset(Context::GLOBAL_INDEX)));
-  movq(rdi, FieldOperand(rdi, GlobalObject::kBuiltinsOffset));
-  int builtins_offset =
-      JSBuiltinsObject::kJSBuiltinsOffset + (id * kPointerSize);
-  movq(rdi, FieldOperand(rdi, builtins_offset));
-  // Load the code entry point from the function into the target register.
-  movq(target, FieldOperand(rdi, JSFunction::kSharedFunctionInfoOffset));
-  movq(target, FieldOperand(target, SharedFunctionInfo::kCodeOffset));
-  addq(target, Immediate(Code::kHeaderSize - kHeapObjectTag));
+  movq(rdi, FieldOperand(target, JSBuiltinsObject::OffsetOfFunctionWithId(id)));
+
+  // Load the code entry point from the builtins object.
+  movq(target, FieldOperand(target, JSBuiltinsObject::OffsetOfCodeWithId(id)));
+  lea(target, FieldOperand(target, Code::kHeaderSize));
 }
 
 
 void MacroAssembler::Set(Register dst, int64_t x) {
   if (x == 0) {
     xor_(dst, dst);
   } else if (is_int32(x)) {
     movq(dst, Immediate(static_cast<int32_t>(x)));
   } else if (is_uint32(x)) {
     movl(dst, Immediate(static_cast<uint32_t>(x)));
@@ skipping 2169 matching lines @@
 CodePatcher::~CodePatcher() {
   // Indicate that code has changed.
   CPU::FlushICache(address_, size_);
 
   // 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