[interpreter] Add a safety-net for interpreter entry.

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 97314dcc27766681f4d6cc0117b56a867a33ef80..581380d86f67d6a840c1cf748a728d15cad6a164 100644
--- a/src/mips/builtins-mips.cc
+++ b/src/mips/builtins-mips.cc
@@ -864,10 +864,8 @@ void Builtins::Generate_JSConstructEntryTrampoline(MacroAssembler* masm) {
 //   o sp: stack pointer
 //   o ra: return address
 //
-// The function builds a JS frame. Please see JavaScriptFrameConstants in
-// frames-mips.h for its layout.
-// TODO(rmcilroy): We will need to include the current bytecode pointer in the
-// frame.
+// The function builds an interpreter frame.  See InterpreterFrameConstants in
+// frames.h for its layout.
 void Builtins::Generate_InterpreterEntryTrampoline(MacroAssembler* masm) {
   // Open a frame scope to indicate that there is a frame on the stack.  The
   // MANUAL indicates that the scope shouldn't actually generate code to set up
@@ -964,6 +962,9 @@ void Builtins::Generate_InterpreterEntryTrampoline(MacroAssembler* masm) {
   // and header removal.
   __ Addu(at, at, Operand(Code::kHeaderSize - kHeapObjectTag));
   __ Call(at);
+
+  // Even though the first bytecode handler was called, we will never return.
+  __ Abort(kUnexpectedReturnFromBytecodeHandler);
 }