[turbofan] Advance bytecode offset after lazy deopt.

src/builtins/arm/builtins-arm.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_ARM
 
 #include "src/codegen.h"
 #include "src/debug/debug.h"
 #include "src/deoptimizer.h"
 #include "src/full-codegen/full-codegen.h"
@@ skipping 1278 matching lines @@
   __ TailCallStub(&stub);
 
   __ bind(&stack_overflow);
   {
     __ TailCallRuntime(Runtime::kThrowStackOverflow);
     // Unreachable code.
     __ bkpt(0);
   }
 }
 
-void Builtins::Generate_InterpreterEnterBytecodeDispatch(MacroAssembler* masm) {
+static void Generate_InterpreterEnterBytecode(MacroAssembler* masm) {
   // Set the return address to the correct point in the interpreter entry
   // trampoline.
   Smi* interpreter_entry_return_pc_offset(
       masm->isolate()->heap()->interpreter_entry_return_pc_offset());
   DCHECK_NE(interpreter_entry_return_pc_offset, Smi::kZero);
   __ Move(r2, masm->isolate()->builtins()->InterpreterEntryTrampoline());
   __ add(lr, r2, Operand(interpreter_entry_return_pc_offset->value() +
                          Code::kHeaderSize - kHeapObjectTag));
 
   // Initialize the dispatch table register.
@@ skipping 20 matching lines @@
   __ SmiUntag(kInterpreterBytecodeOffsetRegister);
 
   // Dispatch to the target bytecode.
   __ ldrb(r1, MemOperand(kInterpreterBytecodeArrayRegister,
                          kInterpreterBytecodeOffsetRegister));
   __ ldr(ip, MemOperand(kInterpreterDispatchTableRegister, r1, LSL,
                         kPointerSizeLog2));
   __ mov(pc, ip);
 }
 
+void Builtins::Generate_InterpreterEnterBytecodeAdvance(MacroAssembler* masm) {
+  // Advance the current bytecode offset stored within the given interpreter
+  // stack frame. This simulates what all bytecode handlers do upon completion
+  // of the underlying operation.
+  {
+    FrameScope scope(masm, StackFrame::MANUAL);

[rmcilroy, 2016/11/09 14:48:29]

Any reason this couldn't be a standard runtime call? It would seem simpler to me
rather than having to prepare a C++ call frame. 

[Michael Starzinger, 2016/11/10 10:09:40]

Done.

+    __ stm(db_w, sp, kCallerSaved);
+    __ PrepareCallCFunction(2, 0, r1);
+    __ ldr(r0, MemOperand(fp, InterpreterFrameConstants::kBytecodeArrayFromFp));
+    __ ldr(r1,
+           MemOperand(fp, InterpreterFrameConstants::kBytecodeOffsetFromFp));
+    __ SmiUntag(r1);
+    __ CallCFunction(
+        ExternalReference::interpreter_advance_bytecode_offset(masm->isolate()),
+        2);
+    __ SmiTag(r0);
+    __ str(r0,
+           MemOperand(fp, InterpreterFrameConstants::kBytecodeOffsetFromFp));
+    __ ldm(ia_w, sp, kCallerSaved);
+  }
+
+  Generate_InterpreterEnterBytecode(masm);
+}
+
+void Builtins::Generate_InterpreterEnterBytecodeDispatch(MacroAssembler* masm) {
+  Generate_InterpreterEnterBytecode(masm);
+}
+
 void Builtins::Generate_CompileLazy(MacroAssembler* masm) {
   // ----------- S t a t e -------------
   //  -- r0 : argument count (preserved for callee)
   //  -- r3 : new target (preserved for callee)
   //  -- r1 : target function (preserved for callee)
   // -----------------------------------
   // First lookup code, maybe we don't need to compile!
   Label gotta_call_runtime, gotta_call_runtime_no_stack;
   Label try_shared;
   Label loop_top, loop_bottom;
@@ skipping 1537 matching lines @@
     __ bkpt(0);
   }
 }
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_ARM