[Interpreter] Make dispatch table point to code entry instead of code objects.

src/arm64/builtins-arm64.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #if V8_TARGET_ARCH_ARM64
 
 #include "src/arm64/frames-arm64.h"
 #include "src/codegen.h"
 #include "src/debug/debug.h"
 #include "src/deoptimizer.h"
@@ skipping 1029 matching lines @@
          Operand(BytecodeArray::kHeaderSize - kHeapObjectTag));
   __ Mov(kInterpreterDispatchTableRegister,
          Operand(ExternalReference::interpreter_dispatch_table_address(
              masm->isolate())));
 
   // Dispatch to the first bytecode handler for the function.
   __ Ldrb(x1, MemOperand(kInterpreterBytecodeArrayRegister,
                          kInterpreterBytecodeOffsetRegister));
   __ Mov(x1, Operand(x1, LSL, kPointerSizeLog2));
   __ Ldr(ip0, MemOperand(kInterpreterDispatchTableRegister, x1));
-  // TODO(rmcilroy): Make dispatch table point to code entrys to avoid untagging
-  // and header removal.
-  __ Add(ip0, ip0, Operand(Code::kHeaderSize - kHeapObjectTag));
   __ Call(ip0);
 
   // Even though the first bytecode handler was called, we will never return.
   __ Abort(kUnexpectedReturnFromBytecodeHandler);
 
   // Load debug copy of the bytecode array.
   __ Bind(&load_debug_bytecode_array);
   __ Ldr(kInterpreterBytecodeArrayRegister,
          FieldMemOperand(debug_info, DebugInfo::kAbstractCodeIndex));
   __ B(&bytecode_array_loaded);
@@ skipping 53 matching lines @@
          MemOperand(
              kInterpreterRegisterFileRegister,
              InterpreterFrameConstants::kBytecodeOffsetFromRegisterPointer));
   __ SmiUntag(kInterpreterBytecodeOffsetRegister);
 
   // Dispatch to the target bytecode.
   __ Ldrb(x1, MemOperand(kInterpreterBytecodeArrayRegister,
                          kInterpreterBytecodeOffsetRegister));
   __ Mov(x1, Operand(x1, LSL, kPointerSizeLog2));
   __ Ldr(ip0, MemOperand(kInterpreterDispatchTableRegister, x1));
-  __ Add(ip0, ip0, Operand(Code::kHeaderSize - kHeapObjectTag));
   __ Jump(ip0);
 }
 
 
 static void Generate_InterpreterNotifyDeoptimizedHelper(
     MacroAssembler* masm, Deoptimizer::BailoutType type) {
   // Enter an internal frame.
   {
     FrameScope scope(masm, StackFrame::INTERNAL);
 
@@ skipping 1621 matching lines @@
   }
 }
 
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_ARM