[interpreter] Add explicit OSR polling bytecode.

src/runtime/runtime-compiler.cc

 // Copyright 2014 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.
 
 #include "src/runtime/runtime-utils.h"
 
 #include "src/arguments.h"
 #include "src/asmjs/asm-js.h"
 #include "src/compiler.h"
 #include "src/deoptimizer.h"
@@ skipping 199 matching lines @@
   // deoptimized so that we are currently in an unoptimized activation.
   // Check for optimized activations of this function.
   for (JavaScriptFrameIterator it(isolate); !it.done(); it.Advance()) {
     JavaScriptFrame* frame = it.frame();
     if (frame->is_optimized() && frame->function() == *function) return false;
   }
 
   return true;
 }
 
+namespace {
 
-RUNTIME_FUNCTION(Runtime_CompileForOnStackReplacement) {
-  HandleScope scope(isolate);
-  DCHECK(args.length() == 1);
-  CONVERT_ARG_HANDLE_CHECKED(JSFunction, function, 0);
-  Handle<Code> caller_code(function->shared()->code());
+BailoutId DetermineEntryAndDisarmOSRForBaseline(JavaScriptFrame* frame) {
+  Handle<Code> caller_code(frame->function()->shared()->code());
 
-  // We're not prepared to handle a function with arguments object.
-  DCHECK(!function->shared()->uses_arguments());
-
-  CHECK(FLAG_use_osr);
-
-  // Passing the PC in the javascript frame from the caller directly is
+  // Passing the PC in the JavaScript frame from the caller directly is
   // not GC safe, so we walk the stack to get it.
-  JavaScriptFrameIterator it(isolate);
-  JavaScriptFrame* frame = it.frame();
   if (!caller_code->contains(frame->pc())) {
     // Code on the stack may not be the code object referenced by the shared
     // function info.  It may have been replaced to include deoptimization data.
     caller_code = Handle<Code>(frame->LookupCode());
   }
 
+  DCHECK_EQ(frame->LookupCode(), *caller_code);
+  DCHECK_EQ(Code::FUNCTION, caller_code->kind());
+  DCHECK(caller_code->contains(frame->pc()));
+
+  // Revert the patched back edge table, regardless of whether OSR succeeds.
+  BackEdgeTable::Revert(frame->isolate(), *caller_code);
+
   uint32_t pc_offset =
       static_cast<uint32_t>(frame->pc() - caller_code->instruction_start());
 
-#ifdef DEBUG
+  return caller_code->TranslatePcOffsetToAstId(pc_offset);
+}
+
+BailoutId DetermineEntryAndDisarmOSRForInterpreter(JavaScriptFrame* frame) {
+  InterpretedFrame* iframe = reinterpret_cast<InterpretedFrame*>(frame);
+
+  // Note that the bytecode array active on the stack might be different from
+  // the one installed on the function (e.g. patched by debugger). This however
+  // is fine because we guarantee the layout to be in sync, hence any BailoutId
+  // representing the entry point will be valid for any copy of the bytecode.
+  Handle<BytecodeArray> bytecode(iframe->GetBytecodeArray());
+
+  DCHECK(frame->LookupCode()->is_interpreter_trampoline_builtin());
+  DCHECK(frame->function()->shared()->HasBytecodeArray());
+  DCHECK(frame->is_interpreted());
+  DCHECK(FLAG_ignition_osr);
+
+  // Reset the OSR loop nesting depth to disarm back edges.
+  bytecode->set_osr_loop_nesting_level(0);
+
+  return BailoutId(iframe->GetBytecodeOffset());
+}
+
+}  // namespace
+
+RUNTIME_FUNCTION(Runtime_CompileForOnStackReplacement) {
+  HandleScope scope(isolate);
+  DCHECK(args.length() == 1);
+  CONVERT_ARG_HANDLE_CHECKED(JSFunction, function, 0);
+
+  // We're not prepared to handle a function with arguments object.
+  DCHECK(!function->shared()->uses_arguments());
+
+  // Only reachable when OST is enabled.
+  CHECK(FLAG_use_osr);
+
+  // Determine frame triggering OSR request.
+  JavaScriptFrameIterator it(isolate);
+  JavaScriptFrame* frame = it.frame();
   DCHECK_EQ(frame->function(), *function);
-  DCHECK_EQ(frame->LookupCode(), *caller_code);
-  DCHECK(caller_code->contains(frame->pc()));
-#endif  // DEBUG
 
-  BailoutId ast_id = caller_code->TranslatePcOffsetToAstId(pc_offset);
+  // Determine the entry point for which this OSR request has been fired and
+  // also disarm all back edges in the calling code to stop new requests.
+  BailoutId ast_id = frame->is_interpreted()
+                         ? DetermineEntryAndDisarmOSRForInterpreter(frame)
+                         : DetermineEntryAndDisarmOSRForBaseline(frame);
   DCHECK(!ast_id.IsNone());
 
   MaybeHandle<Code> maybe_result;
   if (IsSuitableForOnStackReplacement(isolate, function)) {
     if (FLAG_trace_osr) {
       PrintF("[OSR - Compiling: ");
       function->PrintName();
       PrintF(" at AST id %d]\n", ast_id.ToInt());
     }
     maybe_result = Compiler::GetOptimizedCodeForOSR(function, ast_id, frame);
   }
 
-  // Revert the patched back edge table, regardless of whether OSR succeeds.
-  BackEdgeTable::Revert(isolate, *caller_code);
-
   // Check whether we ended up with usable optimized code.
   Handle<Code> result;
   if (maybe_result.ToHandle(&result) &&
       result->kind() == Code::OPTIMIZED_FUNCTION) {
     DeoptimizationInputData* data =
         DeoptimizationInputData::cast(result->deoptimization_data());
 
     if (data->OsrPcOffset()->value() >= 0) {
       DCHECK(BailoutId(data->OsrAstId()->value()) == ast_id);
       if (FLAG_trace_osr) {
@@ skipping 118 matching lines @@
   DCHECK(is_valid_language_mode(args.smi_at(3)));
   LanguageMode language_mode = static_cast<LanguageMode>(args.smi_at(3));
   DCHECK(args[4]->IsSmi());
   Handle<SharedFunctionInfo> outer_info(args.at<JSFunction>(2)->shared(),
                                         isolate);
   return CompileGlobalEval(isolate, args.at<String>(1), outer_info,
                            language_mode, args.smi_at(4), args.smi_at(5));
 }
 }  // namespace internal
 }  // namespace v8