[interpreter] move the dispatch table off heap.

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 1041 matching lines @@
   //  - Allow simulator stop operations if FLAG_stop_at is set.
   //  - Code aging of the BytecodeArray object.
 
   // Load accumulator, register file, bytecode offset, dispatch table into
   // registers.
   __ LoadRoot(kInterpreterAccumulatorRegister, Heap::kUndefinedValueRootIndex);
   __ Add(kInterpreterRegisterFileRegister, fp,
          Operand(InterpreterFrameConstants::kRegisterFilePointerFromFp));
   __ Mov(kInterpreterBytecodeOffsetRegister,
          Operand(BytecodeArray::kHeaderSize - kHeapObjectTag));
-  __ LoadRoot(kInterpreterDispatchTableRegister,
-              Heap::kInterpreterTableRootIndex);
-  __ Add(kInterpreterDispatchTableRegister, kInterpreterDispatchTableRegister,
-         Operand(FixedArray::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);
@@ skipping 20 matching lines @@
                              BytecodeArray::kParameterSizeOffset));
   __ Drop(x1, 1);
   __ Ret();
 }
 
 
 static void Generate_EnterBytecodeDispatch(MacroAssembler* masm) {
   // Initialize register file register and dispatch table register.
   __ Add(kInterpreterRegisterFileRegister, fp,
          Operand(InterpreterFrameConstants::kRegisterFilePointerFromFp));
-  __ LoadRoot(kInterpreterDispatchTableRegister,
-              Heap::kInterpreterTableRootIndex);
-  __ Add(kInterpreterDispatchTableRegister, kInterpreterDispatchTableRegister,
-         Operand(FixedArray::kHeaderSize - kHeapObjectTag));
+  __ Mov(kInterpreterDispatchTableRegister,
+         Operand(ExternalReference::interpreter_dispatch_table_address(
+             masm->isolate())));
 
   // Get the context from the frame.
   __ Ldr(kContextRegister,
          MemOperand(kInterpreterRegisterFileRegister,
                     InterpreterFrameConstants::kContextFromRegisterPointer));
 
   // Get the bytecode array pointer from the frame.
   __ Ldr(x1,
          MemOperand(kInterpreterRegisterFileRegister,
                     InterpreterFrameConstants::kFunctionFromRegisterPointer));
@@ skipping 1705 matching lines @@
   }
 }
 
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_ARM