One less dependent load in InvokeBuiltin.

src/x64/macro-assembler-x64.cc

Index: src/x64/macro-assembler-x64.cc
diff --git a/src/x64/macro-assembler-x64.cc b/src/x64/macro-assembler-x64.cc
index 2781a8489885e43e72a572b29a4efda3a5c4272f..70d89c0a5ceb53bb8572f994ad9f5730f0045508 100644
--- a/src/x64/macro-assembler-x64.cc
+++ b/src/x64/macro-assembler-x64.cc
@@ -445,16 +445,18 @@ void MacroAssembler::InvokeBuiltin(Builtins::JavaScript id, InvokeFlag 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));
 }