Fix concurrent osr.

src/compiler.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1036 matching lines @@
         }
       }
     }
   }
 
   if (isolate->has_pending_exception()) isolate->clear_pending_exception();
   return false;
 }
 
 
-bool Compiler::InstallOptimizedCode(OptimizingCompiler* optimizing_compiler) {
+Handle<Code> Compiler::InstallOptimizedCode(
+    OptimizingCompiler* optimizing_compiler) {
   SmartPointer<CompilationInfo> info(optimizing_compiler->info());
   // The function may have already been optimized by OSR.  Simply continue.
   // Except when OSR already disabled optimization for some reason.
   if (info->shared_info()->optimization_disabled()) {
     info->AbortOptimization();
     InstallFullCode(*info);
     if (FLAG_trace_concurrent_recompilation) {
       PrintF("  ** aborting optimization for ");
       info->closure()->PrintName();
       PrintF(" as it has been disabled.\n");
     }
     ASSERT(!info->closure()->IsMarkedForInstallingRecompiledCode());
-    return false;
+    return Handle<Code>::null();
   }
 
   Isolate* isolate = info->isolate();
   VMState<COMPILER> state(isolate);
   Logger::TimerEventScope timer(
       isolate, Logger::TimerEventScope::v8_recompile_synchronous);
   // If crankshaft succeeded, install the optimized code else install
   // the unoptimized code.
   OptimizingCompiler::Status status = optimizing_compiler->last_status();
   if (info->HasAbortedDueToDependencyChange()) {
@@ skipping 26 matching lines @@
       PrintF(" installed.\n");
     }
   } else {
     info->AbortOptimization();
     InstallFullCode(*info);
   }
   // Optimized code is finally replacing unoptimized code.  Reset the latter's
   // profiler ticks to prevent too soon re-opt after a deopt.
   info->shared_info()->code()->set_profiler_ticks(0);
   ASSERT(!info->closure()->IsMarkedForInstallingRecompiledCode());
-  return status == OptimizingCompiler::SUCCEEDED;
+  return (status == OptimizingCompiler::SUCCEEDED) ? info->code()
+                                                   : Handle<Code>::null();
 }
 
 
 static uint32_t CurrentPcOffset(Isolate* isolate,
                                 Handle<JSFunction> function,
                                 Handle<Code> unoptimized) {
   JavaScriptFrameIterator it(isolate);
   JavaScriptFrame* frame = it.frame();
   ASSERT(frame->function() == *function);
   ASSERT(frame->LookupCode() == *unoptimized);
@@ skipping 87 matching lines @@
       function->PrintName();
       PrintF("]\n");
     }
     return Handle<Code>::null();
   }
 
   OptimizingCompiler* compiler = isolate->optimizing_compiler_thread()->
                                      FindReadyOSRCandidate(function, pc_offset);
 
   if (compiler != NULL) {
+    BailoutId ast_id = compiler->info()->osr_ast_id();

[titzer, 2013/09/10 11:02:42]

I'm not sure why you pulled this variable out of its scope to this point.

+
     if (FLAG_trace_osr) {
       PrintF("[COSR - optimization complete for ");
       function->PrintName();
       PrintF(", restoring interrupt calls]\n");
     }
     Deoptimizer::RevertInterruptCode(isolate, *unoptimized);
 
     // TODO(titzer): don't install the OSR code into the function.
-    bool succeeded = InstallOptimizedCode(compiler);
+    Handle<Code> result = InstallOptimizedCode(compiler);
 
     isolate->optimizing_compiler_thread()->RemoveStaleOSRCandidates();
 
-    if (!succeeded) {
+    if (result.is_null()) {
       if (FLAG_trace_osr) {
         PrintF("[COSR - optimization failed for ");
         function->PrintName();
         PrintF("]\n");
       }
       return Handle<Code>::null();
     }
-    Handle<Code> result = compiler->info()->code();
-
     // Check the result matches our expectations, and don't use it otherwise.
     if (result->kind() == Code::OPTIMIZED_FUNCTION) {
       DeoptimizationInputData* data =
           DeoptimizationInputData::cast(result->deoptimization_data());
 
       if (data->OsrPcOffset()->value() >= 0) {
-        BailoutId ast_id = compiler->info()->osr_ast_id();
         ASSERT(BailoutId(data->OsrAstId()->value()) == ast_id);
         if (FLAG_trace_osr) {
           PrintF("[COSR - entry at AST id %d, offset %d in optimized code]\n",
                  ast_id.ToInt(), data->OsrPcOffset()->value());
         }
         return result;
       }
     }
     return Handle<Code>::null();
   }
@@ skipping 177 matching lines @@
   AllowHandleDereference allow_deref;
   bool tracing_on = info()->IsStub()
       ? FLAG_trace_hydrogen_stubs
       : (FLAG_trace_hydrogen &&
          info()->closure()->PassesFilter(FLAG_trace_hydrogen_filter));
   return (tracing_on &&
       OS::StrChr(const_cast<char*>(FLAG_trace_phase), name_[0]) != NULL);
 }
 
 } }  // namespace v8::internal