[Interpreter] Remove register file register and replace with LoadParentFramePointer.

src/arm64/builtins-arm64.cc

Index: src/arm64/builtins-arm64.cc
diff --git a/src/arm64/builtins-arm64.cc b/src/arm64/builtins-arm64.cc
index a242129fbb72db042b2d2be7da3db017cf141389..c76cbffbdc67589049861c29942b1e29a5bd9350 100644
--- a/src/arm64/builtins-arm64.cc
+++ b/src/arm64/builtins-arm64.cc
@@ -1052,8 +1052,7 @@ void Builtins::Generate_InterpreterEntryTrampoline(MacroAssembler* masm) {
   // Load accumulator, register file, bytecode offset, dispatch table into
   // registers.
   __ LoadRoot(kInterpreterAccumulatorRegister, Heap::kUndefinedValueRootIndex);
-  __ Add(kInterpreterRegisterFileRegister, fp,
-         Operand(InterpreterFrameConstants::kRegisterFilePointerFromFp));
+  __ Add(x18, fp, Operand(InterpreterFrameConstants::kRegisterFileFromFp));
   __ Mov(kInterpreterBytecodeOffsetRegister,
          Operand(BytecodeArray::kHeaderSize - kHeapObjectTag));
   __ Mov(kInterpreterDispatchTableRegister,
@@ -1079,12 +1078,6 @@ void Builtins::Generate_InterpreterEntryTrampoline(MacroAssembler* masm) {
 
 
 void Builtins::Generate_InterpreterExitTrampoline(MacroAssembler* masm) {
-  // TODO(rmcilroy): List of things not currently dealt with here but done in
-  // fullcodegen's EmitReturnSequence.
-  //  - Supporting FLAG_trace for Runtime::TraceExit.
-  //  - Support profiler (specifically decrementing profiling_counter
-  //    appropriately and calling out to HandleInterrupts if necessary).
-
   // The return value is in accumulator, which is already in x0.
 
   // Leave the frame (also dropping the register file).
@@ -1099,18 +1092,14 @@ void Builtins::Generate_InterpreterExitTrampoline(MacroAssembler* masm) {
 
 
 static void Generate_EnterBytecodeDispatch(MacroAssembler* masm) {
-  // Initialize register file register and dispatch table register.
-  __ Add(kInterpreterRegisterFileRegister, fp,
-         Operand(InterpreterFrameConstants::kRegisterFilePointerFromFp));
+  // Initialize the dispatch table register.
   __ Mov(kInterpreterDispatchTableRegister,
          Operand(ExternalReference::interpreter_dispatch_table_address(
              masm->isolate())));
 
   // Get the bytecode array pointer from the frame.
-  __ Ldr(
-      kInterpreterBytecodeArrayRegister,
-      MemOperand(kInterpreterRegisterFileRegister,
-                 InterpreterFrameConstants::kBytecodeArrayFromRegisterPointer));
+  __ Ldr(kInterpreterBytecodeArrayRegister,
+         MemOperand(fp, InterpreterFrameConstants::kBytecodeArrayFromFp));
 
   if (FLAG_debug_code) {
     // Check function data field is actually a BytecodeArray object.
@@ -1123,9 +1112,7 @@ static void Generate_EnterBytecodeDispatch(MacroAssembler* masm) {
 
   // Get the target bytecode offset from the frame.
   __ Ldr(kInterpreterBytecodeOffsetRegister,
-         MemOperand(
-             kInterpreterRegisterFileRegister,
-             InterpreterFrameConstants::kBytecodeOffsetFromRegisterPointer));
+         MemOperand(fp, InterpreterFrameConstants::kBytecodeOffsetFromFp));
   __ SmiUntag(kInterpreterBytecodeOffsetRegister);
 
   // Dispatch to the target bytecode.