A64: Synchronize with r15358.

src/optimizing-compiler-thread.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 71 matching lines @@
   OptimizingCompiler* optimizing_compiler = NULL;
   input_queue_.Dequeue(&optimizing_compiler);
   Barrier_AtomicIncrement(&queue_length_, static_cast<Atomic32>(-1));
 
   // The function may have already been optimized by OSR.  Simply continue.
   OptimizingCompiler::Status status = optimizing_compiler->OptimizeGraph();
   USE(status);   // Prevent an unused-variable error in release mode.
   ASSERT(status != OptimizingCompiler::FAILED);
 
   // The function may have already been optimized by OSR.  Simply continue.
-  // Mark it for installing before queuing so that we can be sure of the write
-  // order: marking first and (after being queued) installing code second.
+  // Use a mutex to make sure that functions marked for install
+  // are always also queued.
+  ScopedLock mark_and_queue(install_mutex_);
   { Heap::RelocationLock relocation_lock(isolate_->heap());
     AllowHandleDereference ahd;
     optimizing_compiler->info()->closure()->MarkForInstallingRecompiledCode();
   }
   output_queue_.Enqueue(optimizing_compiler);
 }
 
 
 void OptimizingCompilerThread::Stop() {
   ASSERT(!IsOptimizerThread());
   Release_Store(&stop_thread_, static_cast<AtomicWord>(true));
   input_queue_semaphore_->Signal();
   stop_semaphore_->Wait();
 
   if (FLAG_parallel_recompilation_delay != 0) {
-    InstallOptimizedFunctions();
     // Barrier when loading queue length is not necessary since the write
     // happens in CompileNext on the same thread.
-    while (NoBarrier_Load(&queue_length_) > 0) {
-      CompileNext();
-      InstallOptimizedFunctions();
+    while (NoBarrier_Load(&queue_length_) > 0) CompileNext();
+    InstallOptimizedFunctions();
+  } else {
+    OptimizingCompiler* optimizing_compiler;
+    while (input_queue_.Dequeue(&optimizing_compiler)) {
+      // The optimizing compiler is allocated in the CompilationInfo's zone.
+      delete optimizing_compiler->info();
     }
   }
 
   if (FLAG_trace_parallel_recompilation) {
     double compile_time = static_cast<double>(time_spent_compiling_);
     double total_time = static_cast<double>(time_spent_total_);
     double percentage = (compile_time * 100) / total_time;
     PrintF("  ** Compiler thread did %.2f%% useful work\n", percentage);
   }
 }
 
 
 void OptimizingCompilerThread::InstallOptimizedFunctions() {
   ASSERT(!IsOptimizerThread());
   HandleScope handle_scope(isolate_);
-  int functions_installed = 0;
-  while (!output_queue_.IsEmpty()) {
-    OptimizingCompiler* compiler;
-    output_queue_.Dequeue(&compiler);
+  OptimizingCompiler* compiler;
+  while (true) {
+    { // Memory barrier to ensure marked functions are queued.
+      ScopedLock marked_and_queued(install_mutex_);
+      if (!output_queue_.Dequeue(&compiler)) return;
+    }
     Compiler::InstallOptimizedCode(compiler);
-    functions_installed++;
   }
 }
 
 
 void OptimizingCompilerThread::QueueForOptimization(
     OptimizingCompiler* optimizing_compiler) {
   ASSERT(IsQueueAvailable());
   ASSERT(!IsOptimizerThread());
   Barrier_AtomicIncrement(&queue_length_, static_cast<Atomic32>(1));
   optimizing_compiler->info()->closure()->MarkInRecompileQueue();
   input_queue_.Enqueue(optimizing_compiler);
   input_queue_semaphore_->Signal();
 }
 
 
 #ifdef DEBUG
 bool OptimizingCompilerThread::IsOptimizerThread() {
   if (!FLAG_parallel_recompilation) return false;
   return ThreadId::Current().ToInteger() == thread_id_;
 }
 #endif
 
 
 } }  // namespace v8::internal