S390: [Interpreter] Remove register file register and replace with LoadParentFramePointer.

src/s390/builtins-s390.cc

Index: src/s390/builtins-s390.cc
diff --git a/src/s390/builtins-s390.cc b/src/s390/builtins-s390.cc
index 1253760110bb774918671b8961db1ec42b11748e..6d264d1ad85878dbd9963fe2b519ad206a8e9e7c 100644
--- a/src/s390/builtins-s390.cc
+++ b/src/s390/builtins-s390.cc
@@ -1050,8 +1050,7 @@ void Builtins::Generate_InterpreterEntryTrampoline(MacroAssembler* masm) {
   // Load accumulator, register file, bytecode offset, dispatch table into
   // registers.
   __ LoadRoot(kInterpreterAccumulatorRegister, Heap::kUndefinedValueRootIndex);
-  __ AddP(kInterpreterRegisterFileRegister, fp,
-          Operand(InterpreterFrameConstants::kRegisterFilePointerFromFp));
+  __ AddP(r4, fp, Operand(InterpreterFrameConstants::kRegisterFileFromFp));
   __ mov(kInterpreterBytecodeOffsetRegister,
          Operand(BytecodeArray::kHeaderSize - kHeapObjectTag));
   __ mov(kInterpreterDispatchTableRegister,
@@ -1070,12 +1069,6 @@ 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 r2.
 
   // Leave the frame (also dropping the register file).
@@ -1149,18 +1142,14 @@ void Builtins::Generate_InterpreterPushArgsAndConstruct(MacroAssembler* masm) {
 }
 
 static void Generate_EnterBytecodeDispatch(MacroAssembler* masm) {
-  // Initialize register file register and dispatch table register.
-  __ AddP(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.
-  __ LoadP(
-      kInterpreterBytecodeArrayRegister,
-      MemOperand(kInterpreterRegisterFileRegister,
-                 InterpreterFrameConstants::kBytecodeArrayFromRegisterPointer));
+  __ LoadP(kInterpreterBytecodeArrayRegister,
+           MemOperand(fp, InterpreterFrameConstants::kBytecodeArrayFromFp));
 
   if (FLAG_debug_code) {
     // Check function data field is actually a BytecodeArray object.
@@ -1173,9 +1162,7 @@ static void Generate_EnterBytecodeDispatch(MacroAssembler* masm) {
 
   // Get the target bytecode offset from the frame.
   __ LoadP(kInterpreterBytecodeOffsetRegister,
-           MemOperand(
-               kInterpreterRegisterFileRegister,
-               InterpreterFrameConstants::kBytecodeOffsetFromRegisterPointer));
+           MemOperand(fp, InterpreterFrameConstants::kBytecodeOffsetFromFp));
   __ SmiUntag(kInterpreterBytecodeOffsetRegister);
 
   // Dispatch to the target bytecode.