[Interpreter] Save and restore dispatch table pointer during calls.

src/mips/builtins-mips.cc

Index: src/mips/builtins-mips.cc
diff --git a/src/mips/builtins-mips.cc b/src/mips/builtins-mips.cc
index 7cc2ac18ba306f20e8a6c0bba03f92b3fe6977fe..e6be3f8d115d02b9fce420168f51bef0777e0e3f 100644
--- a/src/mips/builtins-mips.cc
+++ b/src/mips/builtins-mips.cc
@@ -977,6 +977,10 @@ void Builtins::Generate_InterpreterEntryTrampoline(MacroAssembler* masm) {
   __ Addu(fp, sp, Operand(StandardFrameConstants::kFixedFrameSizeFromFp));
   __ Push(a3);
 
+  // Push dispatch table pointer.
+  __ li(a0, Operand(ExternalReference::interpreter_dispatch_table_address(
+                masm->isolate())));
+  __ push(a0);
   // Push zero for bytecode array offset.
   __ Push(zero_reg);

[balazs.kilvady, 2016/02/11 10:44:01]

You could use __ Push(a0, zero_reg); to save one addu(sp, ...); instruction.

[rmcilroy, 2016/02/11 12:30:12]

Good idea, done. Also pulled in the pushing of new.target to this push too and
fixed Arm to do the same. Thanks.

 
@@ -1036,9 +1040,8 @@ void Builtins::Generate_InterpreterEntryTrampoline(MacroAssembler* masm) {
           Operand(InterpreterFrameConstants::kRegisterFilePointerFromFp));
   __ li(kInterpreterBytecodeOffsetRegister,
         Operand(BytecodeArray::kHeaderSize - kHeapObjectTag));
-  __ li(kInterpreterDispatchTableRegister,
-        Operand(ExternalReference::interpreter_dispatch_table_address(
-            masm->isolate())));
+  __ lw(kInterpreterDispatchTableRegister,
+        MemOperand(fp, InterpreterFrameConstants::kDispatchTableFromFp));
 
   // Dispatch to the first bytecode handler for the function.
   __ Addu(a0, kInterpreterBytecodeArrayRegister,