Pass PC offset into runtime when compiling for OSR.

R=titzer@chromium.org
BUG=

Review URL: https://codereview.chromium.org/23842004

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16649 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/arm/builtins-arm.cc

@@ -966,13 +966,22 @@ void Builtins::Generate_NotifyOSR(MacroAssembler* masm) {
 
 
 void Builtins::Generate_OnStackReplacement(MacroAssembler* masm) {
-  // Lookup the function in the JavaScript frame and push it as an
-  // argument to the on-stack replacement function.
+  // Lookup the function in the JavaScript frame.
   __ ldr(r0, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset));
   {
     FrameScope scope(masm, StackFrame::INTERNAL);
+    // Lookup and calculate pc offset.
+    __ ldr(r1, MemOperand(fp, StandardFrameConstants::kCallerPCOffset));
+    __ ldr(r2, FieldMemOperand(r0, JSFunction::kSharedFunctionInfoOffset));
+    __ ldr(r2, FieldMemOperand(r2, SharedFunctionInfo::kCodeOffset));
+    __ sub(r1, r1, Operand(Code::kHeaderSize - kHeapObjectTag));
+    __ sub(r1, r1, r2);
+    __ SmiTag(r1);
+
+    // Pass both function and pc offset as arguments.
     __ push(r0);
-    __ CallRuntime(Runtime::kCompileForOnStackReplacement, 1);
+    __ push(r1);
+    __ CallRuntime(Runtime::kCompileForOnStackReplacement, 2);
   }
 
   // If the code object is null, just return to the unoptimized code.

src/compiler.cc

@@ -1120,166 +1120,6 @@ Handle<Code> Compiler::InstallOptimizedCode(
 }
 
 
-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);
-  ASSERT(unoptimized->contains(frame->pc()));
-
-  // Use linear search of the unoptimized code's back edge table to find
-  // the AST id matching the PC.
-  return static_cast<uint32_t>(frame->pc() - unoptimized->instruction_start());
-}
-
-
-static bool IsSuitableForOnStackReplacement(Isolate* isolate,
-                                            Handle<JSFunction> function,
-                                            Handle<Code> unoptimized) {
-  // Keep track of whether we've succeeded in optimizing.
-  if (!unoptimized->optimizable()) return false;
-  // If we are trying to do OSR when there are already optimized
-  // activations of the function, it means (a) the function is directly or
-  // indirectly recursive and (b) an optimized invocation has been
-  // 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;
-}
-
-
-Handle<Code> Compiler::CompileForOnStackReplacement(
-      Handle<JSFunction> function) {
-  Isolate* isolate = function->GetIsolate();
-  Handle<Code> unoptimized(function->shared()->code(), isolate);
-
-  Deoptimizer::RevertInterruptCode(isolate, *unoptimized);
-  if (FLAG_trace_osr) {
-    PrintF("[OSR - restored original interrupt calls in ");
-    function->PrintName();
-    PrintF("]\n");
-  }
-
-  if (IsSuitableForOnStackReplacement(isolate, function, unoptimized)) {
-    // Find the PC offset in unoptimized code and translate to an AST id.
-    uint32_t pc_offset = CurrentPcOffset(isolate, function, unoptimized);
-    BailoutId ast_id = unoptimized->TranslatePcOffsetToAstId(pc_offset);
-    ASSERT(!ast_id.IsNone());
-    if (FLAG_trace_osr) {
-      PrintF("[OSR - replacing at AST id %d in ", ast_id.ToInt());
-      function->PrintName();
-      PrintF("]\n");
-    }
-
-    // Attempt OSR compilation.
-    Handle<Code> result = JSFunction::CompileOsr(
-        function, ast_id, CLEAR_EXCEPTION);
-
-    if (!result.is_null() && result->kind() == Code::OPTIMIZED_FUNCTION) {
-      // OSR compilation succeeded.
-      DeoptimizationInputData* data =
-          DeoptimizationInputData::cast(result->deoptimization_data());
-      if (FLAG_trace_osr) {
-        PrintF("[OSR - entry, offset %d in optimized code]\n",
-            data->OsrPcOffset()->value());
-      }
-      ASSERT(BailoutId(data->OsrAstId()->value()) == ast_id);
-      return result;
-    }
-  }
-
-  if (FLAG_trace_osr) {
-    PrintF("[OSR - attempt failed for ");
-    function->PrintName();
-    PrintF("]\n");
-  }
-  return Handle<Code>::null();
-}
-
-
-Handle<Code> Compiler::CompileForConcurrentOSR(Handle<JSFunction> function) {
-  Isolate* isolate = function->GetIsolate();
-  Handle<Code> unoptimized(function->shared()->code(), isolate);
-
-  uint32_t pc_offset = CurrentPcOffset(isolate, function, unoptimized);
-
-  if (isolate->optimizing_compiler_thread()->
-          IsQueuedForOSR(function, pc_offset)) {
-    // Still waiting for the optimizing compiler thread to finish.  Carry on.
-    if (FLAG_trace_osr) {
-      PrintF("[COSR - polling recompile tasks for ");
-      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();
-
-    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.
-    Handle<Code> result = InstallOptimizedCode(compiler);
-
-    isolate->optimizing_compiler_thread()->RemoveStaleOSRCandidates();
-
-    if (result.is_null()) {
-      if (FLAG_trace_osr) {
-        PrintF("[COSR - optimization failed for ");
-        function->PrintName();
-        PrintF("]\n");
-      }
-      return Handle<Code>::null();
-    }
-    // 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) {
-        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();
-  }
-
-  if (!IsSuitableForOnStackReplacement(isolate, function, unoptimized)) {
-    if (FLAG_trace_osr) {
-      PrintF("[COSR - ");
-      function->PrintName();
-      PrintF(" is unsuitable, restoring interrupt calls]\n");
-    }
-    Deoptimizer::RevertInterruptCode(isolate, *unoptimized);
-    return Handle<Code>::null();
-  }
-
-  if (!RecompileConcurrent(function, pc_offset)) {
-    Deoptimizer::RevertInterruptCode(isolate, *unoptimized);
-  }
-  return Handle<Code>::null();
-}
-
-
 Handle<SharedFunctionInfo> Compiler::BuildFunctionInfo(FunctionLiteral* literal,
                                                        Handle<Script> script) {
   // Precondition: code has been parsed and scopes have been analyzed.

src/compiler.h

@@ -627,10 +627,6 @@ class Compiler : public AllStatic {
 
   static Handle<Code> InstallOptimizedCode(OptimizingCompiler* info);
 
-  static Handle<Code> CompileForOnStackReplacement(Handle<JSFunction> function);
-
-  static Handle<Code> CompileForConcurrentOSR(Handle<JSFunction> function);
-
 #ifdef ENABLE_DEBUGGER_SUPPORT
   static bool MakeCodeForLiveEdit(CompilationInfo* info);
 #endif

src/ia32/builtins-ia32.cc

@@ -1327,14 +1327,21 @@ void Builtins::Generate_ArgumentsAdaptorTrampoline(MacroAssembler* masm) {
 
 
 void Builtins::Generate_OnStackReplacement(MacroAssembler* masm) {
+  // Lookup the function in the JavaScript frame.
   __ mov(eax, Operand(ebp, JavaScriptFrameConstants::kFunctionOffset));
-
-  // Pass the function to optimize as the argument to the on-stack
-  // replacement runtime function.
   {
     FrameScope scope(masm, StackFrame::INTERNAL);
+    // Lookup and calculate pc offset.
+    __ mov(edx, Operand(ebp, StandardFrameConstants::kCallerPCOffset));
+    __ mov(ebx, FieldOperand(eax, JSFunction::kSharedFunctionInfoOffset));
+    __ sub(edx, Immediate(Code::kHeaderSize - kHeapObjectTag));
+    __ sub(edx, FieldOperand(ebx, SharedFunctionInfo::kCodeOffset));
+    __ SmiTag(edx);
+
+    // Pass both function and pc offset as arguments.
     __ push(eax);
-    __ CallRuntime(Runtime::kCompileForOnStackReplacement, 1);
+    __ push(edx);
+    __ CallRuntime(Runtime::kCompileForOnStackReplacement, 2);
   }
 
   Label skip;

src/mips/builtins-mips.cc

@@ -1000,13 +1000,22 @@ void Builtins::Generate_NotifyOSR(MacroAssembler* masm) {
 
 
 void Builtins::Generate_OnStackReplacement(MacroAssembler* masm) {
-  // Lookup the function in the JavaScript frame and push it as an
-  // argument to the on-stack replacement function.
+  // Lookup the function in the JavaScript frame.
   __ lw(a0, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset));
   {
     FrameScope scope(masm, StackFrame::INTERNAL);
+    // Lookup and calculate pc offset.
+    __ lw(a1, MemOperand(fp, StandardFrameConstants::kCallerPCOffset));
+    __ lw(a2, FieldMemOperand(a0, JSFunction::kSharedFunctionInfoOffset));
+    __ lw(a2, FieldMemOperand(a2, SharedFunctionInfo::kCodeOffset));
+    __ Subu(a1, a1, Operand(Code::kHeaderSize - kHeapObjectTag));
+    __ Subu(a1, a1, a2);
+    __ SmiTag(a1);
+
+    // Pass both function and pc offset as arguments.
     __ push(a0);
-    __ CallRuntime(Runtime::kCompileForOnStackReplacement, 1);
+    __ push(a1);
+    __ CallRuntime(Runtime::kCompileForOnStackReplacement, 2);
   }
 
   // If the code object is null, just return to the unoptimized code.

src/optimizing-compiler-thread.cc

@@ -234,14 +234,18 @@ void OptimizingCompilerThread::QueueForOptimization(
 OptimizingCompiler* OptimizingCompilerThread::FindReadyOSRCandidate(
     Handle<JSFunction> function, uint32_t osr_pc_offset) {
   ASSERT(!IsOptimizerThread());
-  LockGuard<Mutex> access_osr_lists(&osr_list_mutex_);
-  for (int i = 0; i < ready_for_osr_.length(); i++) {
-    if (ready_for_osr_[i]->info()->HasSameOsrEntry(function, osr_pc_offset)) {
-      osr_hits_++;
-      return ready_for_osr_.Remove(i);
+  OptimizingCompiler* result = NULL;
+  { LockGuard<Mutex> access_osr_lists(&osr_list_mutex_);
+    for (int i = 0; i < ready_for_osr_.length(); i++) {
+      if (ready_for_osr_[i]->info()->HasSameOsrEntry(function, osr_pc_offset)) {
+        osr_hits_++;
+        result = ready_for_osr_.Remove(i);
+        break;
+      }
     }
   }
-  return NULL;
+  RemoveStaleOSRCandidates();
+  return result;
 }
 
 
@@ -258,6 +262,18 @@ bool OptimizingCompilerThread::IsQueuedForOSR(Handle<JSFunction> function,
 }
 
 
+bool OptimizingCompilerThread::IsQueuedForOSR(JSFunction* function) {
+  ASSERT(!IsOptimizerThread());
+  LockGuard<Mutex> access_osr_lists(&osr_list_mutex_);
+  for (int i = 0; i < osr_candidates_.length(); i++) {
+    if (*osr_candidates_[i]->info()->closure() == function) {
+      return true;
+    }
+  }
+  return false;
+}
+
+
 void OptimizingCompilerThread::RemoveStaleOSRCandidates(int limit) {
   ASSERT(!IsOptimizerThread());
   LockGuard<Mutex> access_osr_lists(&osr_list_mutex_);

src/optimizing-compiler-thread.h

@@ -71,9 +71,7 @@ class OptimizingCompilerThread : public Thread {
                                             uint32_t osr_pc_offset);
   bool IsQueuedForOSR(Handle<JSFunction> function, uint32_t osr_pc_offset);
 
-  // Remove the oldest OSR candidates that are ready so that we
-  // only have |limit| left waiting.
-  void RemoveStaleOSRCandidates(int limit = kReadyForOSRLimit);
+  bool IsQueuedForOSR(JSFunction* function);
 
   inline bool IsQueueAvailable() {
     // We don't need a barrier since we have a data dependency right
@@ -96,6 +94,10 @@ class OptimizingCompilerThread : public Thread {
  private:
   enum StopFlag { CONTINUE, STOP, FLUSH };
 
+  // Remove the oldest OSR candidates that are ready so that we
+  // only have |limit| left waiting.
+  void RemoveStaleOSRCandidates(int limit = kReadyForOSRLimit);
+
   void FlushInputQueue(bool restore_function_code);
   void FlushOutputQueue(bool restore_function_code);
   void CompileNext();

src/runtime-profiler.cc

@@ -139,7 +139,16 @@ void RuntimeProfiler::Optimize(JSFunction* function, const char* reason) {
     PrintF("]\n");
   }
 
+
   if (FLAG_concurrent_recompilation && !isolate_->bootstrapper()->IsActive()) {
+    if (FLAG_concurrent_osr &&
+        isolate_->optimizing_compiler_thread()->IsQueuedForOSR(function)) {
+      // Do not attempt regular recompilation if we already queued this for OSR.
+      // TODO(yangguo): This is necessary so that we don't install optimized
+      // code on a function that is already optimized, since OSR and regular
+      // recompilation race.  This goes away as soon as OSR becomes one-shot.
+      return;
+    }
     ASSERT(!function->IsMarkedForInstallingRecompiledCode());
     ASSERT(!function->IsInRecompileQueue());
     function->MarkForConcurrentRecompilation();
@@ -224,6 +233,8 @@ void RuntimeProfiler::OptimizeNow() {
     isolate_->optimizing_compiler_thread()->InstallOptimizedFunctions();
   }
 
+  DisallowHeapAllocation no_gc;
+
   // Run through the JavaScript frames and collect them. If we already
   // have a sample of the function, we mark it for optimizations
   // (eagerly or lazily).

src/runtime.cc

@@ -8579,38 +8579,125 @@ RUNTIME_FUNCTION(MaybeObject*, Runtime_GetOptimizationCount) {
 }
 
 
+static bool IsSuitableForOnStackReplacement(Isolate* isolate,
+                                            Handle<JSFunction> function,
+                                            Handle<Code> unoptimized) {
+  // Keep track of whether we've succeeded in optimizing.
+  if (!unoptimized->optimizable()) return false;
+  // If we are trying to do OSR when there are already optimized
+  // activations of the function, it means (a) the function is directly or
+  // indirectly recursive and (b) an optimized invocation has been
+  // 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;
+}
+
+
 RUNTIME_FUNCTION(MaybeObject*, Runtime_CompileForOnStackReplacement) {
   HandleScope scope(isolate);
-  ASSERT(args.length() == 1);
+  ASSERT(args.length() == 2);
   CONVERT_ARG_HANDLE_CHECKED(JSFunction, function, 0);
+  CONVERT_NUMBER_CHECKED(uint32_t, pc_offset, Uint32, args[1]);
+  Handle<Code> unoptimized(function->shared()->code(), isolate);
+
+#ifdef DEBUG
+  JavaScriptFrameIterator it(isolate);
+  JavaScriptFrame* frame = it.frame();
+  ASSERT_EQ(frame->function(), *function);
+  ASSERT_EQ(frame->LookupCode(), *unoptimized);
+  ASSERT(unoptimized->contains(frame->pc()));
+
+  ASSERT(pc_offset ==
+         static_cast<uint32_t>(frame->pc() - unoptimized->instruction_start()));
+#endif  // DEBUG
 
   // We're not prepared to handle a function with arguments object.
   ASSERT(!function->shared()->uses_arguments());
 
-  // If the optimization attempt succeeds, return the code object which
-  // the unoptimized code can jump into.
-  Handle<Code> code =
-      (FLAG_concurrent_recompilation && FLAG_concurrent_osr)
-          ? Compiler::CompileForConcurrentOSR(function)
-          : Compiler::CompileForOnStackReplacement(function);
-  if (!code.is_null()) {
-#if DEBUG
-    ASSERT(code->kind() == Code::OPTIMIZED_FUNCTION);
+  Handle<Code> result = Handle<Code>::null();
+  BailoutId ast_id = BailoutId::None();
+
+  if (FLAG_concurrent_recompilation && FLAG_concurrent_osr) {
+    if (isolate->optimizing_compiler_thread()->
+            IsQueuedForOSR(function, pc_offset)) {
+      // Still waiting for the optimizing compiler thread to finish.  Carry on.
+      if (FLAG_trace_osr) {
+        PrintF("[COSR - polling recompile tasks for ");
+        function->PrintName();
+        PrintF("]\n");
+      }
+      return NULL;
+    }
+
+    OptimizingCompiler* compiler = isolate->optimizing_compiler_thread()->
+        FindReadyOSRCandidate(function, pc_offset);
+
+    if (compiler == NULL) {
+      if (IsSuitableForOnStackReplacement(isolate, function, unoptimized) &&
+          Compiler::RecompileConcurrent(function, pc_offset)) {
+        if (function->IsMarkedForLazyRecompilation() ||
+            function->IsMarkedForConcurrentRecompilation()) {
+          // Prevent regular recompilation if we queue this for OSR.
+          // TODO(yangguo): remove this as soon as OSR becomes one-shot.
+          function->ReplaceCode(function->shared()->code());
+        }
+        return NULL;
+      }
+      // Fall through to the end in case of failure.
+    } else {
+      // TODO(titzer): don't install the OSR code into the function.
+      ast_id = compiler->info()->osr_ast_id();
+      result = Compiler::InstallOptimizedCode(compiler);
+    }
+  } else if (IsSuitableForOnStackReplacement(isolate, function, unoptimized)) {
+    ast_id = unoptimized->TranslatePcOffsetToAstId(pc_offset);
+    ASSERT(!ast_id.IsNone());
+    if (FLAG_trace_osr) {
+      PrintF("[OSR - replacing at AST id %d in ", ast_id.ToInt());
+      function->PrintName();
+      PrintF("]\n");
+    }
+    // Attempt OSR compilation.
+    result = JSFunction::CompileOsr(function, ast_id, CLEAR_EXCEPTION);
+  }
+
+  // Revert the patched interrupt now, regardless of whether OSR succeeds.
+  Deoptimizer::RevertInterruptCode(isolate, *unoptimized);
+
+  // Check whether we ended up with usable optimized code.
+  if (!result.is_null() && result->kind() == Code::OPTIMIZED_FUNCTION) {
     DeoptimizationInputData* data =
-        DeoptimizationInputData::cast(code->deoptimization_data());
-    ASSERT(!BailoutId(data->OsrAstId()->value()).IsNone());
-#endif
-    // TODO(titzer): this is a massive hack to make the deopt counts
-    // match. Fix heuristics for reenabling optimizations!
-    function->shared()->increment_deopt_count();
-    return *code;
-  } else {
-    if (function->IsMarkedForLazyRecompilation() ||
-        function->IsMarkedForConcurrentRecompilation()) {
-      function->ReplaceCode(function->shared()->code());
+        DeoptimizationInputData::cast(result->deoptimization_data());
+
+    if (data->OsrPcOffset()->value() >= 0) {
+      ASSERT(BailoutId(data->OsrAstId()->value()) == ast_id);
+      if (FLAG_trace_osr) {
+        PrintF("[OSR - entry at AST id %d, offset %d in optimized code]\n",
+               ast_id.ToInt(), data->OsrPcOffset()->value());
+      }
+      // TODO(titzer): this is a massive hack to make the deopt counts
+      // match. Fix heuristics for reenabling optimizations!
+      function->shared()->increment_deopt_count();
+      return *result;
     }
-    return NULL;
   }
+
+  if (FLAG_trace_osr) {
+    PrintF("[OSR - optimization failed for ");
+    function->PrintName();
+    PrintF("]\n");
+  }
+
+  if (function->IsMarkedForLazyRecompilation() ||
+      function->IsMarkedForConcurrentRecompilation()) {
+    function->ReplaceCode(function->shared()->code());
+  }
+  return NULL;
 }
 
 

src/runtime.h

@@ -100,7 +100,7 @@ namespace internal {
   F(NeverOptimizeFunction, 1, 1) \
   F(GetOptimizationStatus, -1, 1) \
   F(GetOptimizationCount, 1, 1) \
-  F(CompileForOnStackReplacement, 1, 1) \
+  F(CompileForOnStackReplacement, 2, 1) \
   F(SetAllocationTimeout, 2, 1) \
   F(AllocateInNewSpace, 1, 1) \
   F(AllocateInOldPointerSpace, 1, 1) \

src/x64/builtins-x64.cc

@@ -1408,14 +1408,21 @@ void Builtins::Generate_ArgumentsAdaptorTrampoline(MacroAssembler* masm) {
 
 
 void Builtins::Generate_OnStackReplacement(MacroAssembler* masm) {
+  // Lookup the function in the JavaScript frame.
   __ movq(rax, Operand(rbp, JavaScriptFrameConstants::kFunctionOffset));
-
-  // Pass the function to optimize as the argument to the on-stack
-  // replacement runtime function.
   {
     FrameScope scope(masm, StackFrame::INTERNAL);
+    // Lookup and calculate pc offset.
+    __ movq(rdx, Operand(rbp, StandardFrameConstants::kCallerPCOffset));
+    __ movq(rbx, FieldOperand(rax, JSFunction::kSharedFunctionInfoOffset));
+    __ subq(rdx, Immediate(Code::kHeaderSize - kHeapObjectTag));
+    __ subq(rdx, FieldOperand(rbx, SharedFunctionInfo::kCodeOffset));
+    __ Integer32ToSmi(rdx, rdx);
+
+    // Pass both function and pc offset as arguments.
     __ push(rax);
-    __ CallRuntime(Runtime::kCompileForOnStackReplacement, 1);
+    __ push(rdx);
+    __ CallRuntime(Runtime::kCompileForOnStackReplacement, 2);
   }
 
   Label skip;