[turbofan] Gracefully bail out if OSR encounters a loop too deeply nested.

src/compiler/pipeline.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/compiler/pipeline.h"
 
 #include <fstream>  // NOLINT(readability/streams)
 #include <sstream>
 
 #include "src/base/platform/elapsed-timer.h"
@@ skipping 396 matching lines @@
 };
 
 
 struct OsrDeconstructionPhase {
   static const char* phase_name() { return "OSR deconstruction"; }
 
   void Run(PipelineData* data, Zone* temp_zone) {
     SourcePositionTable::Scope pos(data->source_positions(),
                                    SourcePosition::Unknown());
     OsrHelper osr_helper(data->info());
-    osr_helper.Deconstruct(data->jsgraph(), data->common(), temp_zone);
+    bool success =
+        osr_helper.Deconstruct(data->jsgraph(), data->common(), temp_zone);
+    if (!success) data->info()->RetryOptimization(kOsrCompileFailed);
   }
 };
 
 
 struct TypedLoweringPhase {
   static const char* phase_name() { return "typed lowering"; }
 
   void Run(PipelineData* data, Zone* temp_zone) {
     SourcePositionTable::Scope pos(data->source_positions(),
                                    SourcePosition::Unknown());
@@ skipping 339 matching lines @@
   if (FLAG_trace_turbo) {
     Run<PrintGraphPhase>(phase);
   }
   if (FLAG_turbo_verify) {
     Run<VerifyGraphPhase>(untyped);
   }
 }
 
 
 Handle<Code> Pipeline::GenerateCode() {
-  // TODO(turbofan): Make OSR work with inner loops and remove this bailout.
-  if (info()->is_osr() && !FLAG_turbo_osr) return Handle<Code>::null();
+  if (info()->is_osr() && !FLAG_turbo_osr) {
+    // TODO(turbofan): remove this flag and always handle OSR
+    info()->RetryOptimization(kOsrCompileFailed);
+    return Handle<Code>::null();
+  }
 
   // TODO(mstarzinger): This is just a temporary hack to make TurboFan work,
   // the correct solution is to restore the context register after invoking
   // builtins from full-codegen.
   Handle<SharedFunctionInfo> shared = info()->shared_info();
   if (isolate()->bootstrapper()->IsActive() ||
       shared->disable_optimization_reason() ==
           kBuiltinFunctionCannotBeOptimized) {
     shared->DisableOptimization(kBuiltinFunctionCannotBeOptimized);
     return Handle<Code>::null();
@@ skipping 67 matching lines @@
     Run<TypedLoweringPhase>();
     RunPrintAndVerify("Lowered typed");
 
     if (FLAG_turbo_stress_loop_peeling) {
       Run<StressLoopPeelingPhase>();
       RunPrintAndVerify("Loop peeled", true);
     }
 
     if (info()->is_osr()) {
       Run<OsrDeconstructionPhase>();
+      if (info()->bailout_reason() != kNoReason) return Handle<Code>::null();
       RunPrintAndVerify("OSR deconstruction");
     }
 
     // Lower simplified operators and insert changes.
     Run<SimplifiedLoweringPhase>();
     RunPrintAndVerify("Lowered simplified");
 
     // Lower changes that have been inserted before.
     Run<ChangeLoweringPhase>();
     // // TODO(jarin, rossberg): Remove UNTYPED once machine typing works.
     RunPrintAndVerify("Lowered changes", true);
 
     Run<LateControlReductionPhase>();
     RunPrintAndVerify("Late Control reduced");
   } else {
     if (info()->is_osr()) {
       Run<OsrDeconstructionPhase>();
+      if (info()->bailout_reason() != kNoReason) return Handle<Code>::null();
       RunPrintAndVerify("OSR deconstruction");
     }
   }
 
   // Lower any remaining generic JSOperators.
   Run<GenericLoweringPhase>();
   // TODO(jarin, rossberg): Remove UNTYPED once machine typing works.
   RunPrintAndVerify("Lowered generic", true);
 
   BeginPhaseKind("block building");
@@ skipping 221 matching lines @@
 }
 
 
 void Pipeline::TearDown() {
   InstructionOperand::TearDownCaches();
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8