[interpreter] move the dispatch table off heap.

src/arm/builtins-arm.cc

Index: src/arm/builtins-arm.cc
diff --git a/src/arm/builtins-arm.cc b/src/arm/builtins-arm.cc
index bb9c06cdd56996845de36edf015296592b1a87d0..ca05f81e80691f3d80b6c2c52e274ff20b677ad5 100644
--- a/src/arm/builtins-arm.cc
+++ b/src/arm/builtins-arm.cc
@@ -1049,10 +1049,9 @@ void Builtins::Generate_InterpreterEntryTrampoline(MacroAssembler* masm) {
          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(r1, MemOperand(kInterpreterBytecodeArrayRegister,
@@ -1154,10 +1153,9 @@ 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,