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

src/x64/builtins-x64.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #if V8_TARGET_ARCH_X64
 
 #include "src/code-factory.h"
 #include "src/codegen.h"
 #include "src/deoptimizer.h"
 #include "src/full-codegen/full-codegen.h"
@@ skipping 586 matching lines @@
 // stack left to right.  The actual argument count matches the formal parameter
 // count expected by the function.
 //
 // The live registers are:
 //   o rdi: the JS function object being called
 //   o rdx: the new target
 //   o rsi: our context
 //   o rbp: the caller's frame pointer
 //   o rsp: stack pointer (pointing to return address)
 //
-// The function builds a JS frame.  Please see JavaScriptFrameConstants in
-// frames-x64.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
   // the frame (that is done below).
   FrameScope frame_scope(masm, StackFrame::MANUAL);
   __ pushq(rbp);  // Caller's frame pointer.
   __ movp(rbp, rsp);
   __ Push(rsi);  // Callee's context.
   __ Push(rdi);  // Callee's JS function.
   __ Push(rdx);  // Callee's new target.
@@ skipping 77 matching lines @@
 
   // Dispatch to the first bytecode handler for the function.
   __ movzxbp(rbx, Operand(kInterpreterBytecodeArrayRegister,
                           kInterpreterBytecodeOffsetRegister, times_1, 0));
   __ movp(rbx, Operand(kInterpreterDispatchTableRegister, rbx,
                        times_pointer_size, 0));
   // TODO(rmcilroy): Make dispatch table point to code entrys to avoid untagging
   // and header removal.
   __ addp(rbx, Immediate(Code::kHeaderSize - kHeapObjectTag));
   __ call(rbx);
+
+  // Even though the first bytecode handler was called, we will never return.
+  __ Abort(kUnexpectedReturnFromBytecodeHandler);
 }
 
 
 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).
 
@@ skipping 2034 matching lines @@
   __ ret(0);
 }
 
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_X64