Refactor building of lazy bailouts in AstGraphBuilder.

src/compiler/ast-graph-builder.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/ast-graph-builder.h"
 
 #include "src/compiler.h"
 #include "src/compiler/control-builders.h"
 #include "src/compiler/node-properties.h"
 #include "src/compiler/node-properties-inl.h"
@@ skipping 220 matching lines @@
     stack_dirty_ = false;
   }
 
   Operator* op = common()->FrameState(ast_id);
 
   return graph()->NewNode(op, parameters_node_, locals_node_, stack_node_);
 }
 
 
 AstGraphBuilder::AstContext::AstContext(AstGraphBuilder* own,
-                                        Expression::Context kind,
-                                        BailoutId bailout_id)
-    : bailout_id_(bailout_id),
-      kind_(kind),
-      owner_(own),
-      outer_(own->ast_context()) {
+                                        Expression::Context kind)
+    : kind_(kind), owner_(own), outer_(own->ast_context()) {
   owner()->set_ast_context(this);  // Push.
 #ifdef DEBUG
   original_height_ = environment()->stack_height();
 #endif
 }
 
 
 AstGraphBuilder::AstContext::~AstContext() {
   owner()->set_ast_context(outer_);  // Pop.
 }
 
 
 AstGraphBuilder::AstEffectContext::~AstEffectContext() {
   DCHECK(environment()->stack_height() == original_height_);
 }
 
 
 AstGraphBuilder::AstValueContext::~AstValueContext() {
   DCHECK(environment()->stack_height() == original_height_ + 1);
 }
 
 
 AstGraphBuilder::AstTestContext::~AstTestContext() {
   DCHECK(environment()->stack_height() == original_height_ + 1);
 }
 
 
-void AstGraphBuilder::AstEffectContext::ProduceValueWithLazyBailout(
-    Node* value) {
-  ProduceValue(value);
-  owner()->BuildLazyBailout(value, bailout_id_);
-}
-
-
-void AstGraphBuilder::AstValueContext::ProduceValueWithLazyBailout(
-    Node* value) {
-  ProduceValue(value);
-  owner()->BuildLazyBailout(value, bailout_id_);
-}
-
-
-void AstGraphBuilder::AstTestContext::ProduceValueWithLazyBailout(Node* value) {
-  environment()->Push(value);
-  owner()->BuildLazyBailout(value, bailout_id_);
-  environment()->Pop();
-  ProduceValue(value);
-}
-
-
 void AstGraphBuilder::AstEffectContext::ProduceValue(Node* value) {
   // The value is ignored.
 }
 
 
 void AstGraphBuilder::AstValueContext::ProduceValue(Node* value) {
   environment()->Push(value);
 }
 
 
@@ skipping 46 matching lines @@
 
 
 void AstGraphBuilder::VisitForValues(ZoneList<Expression*>* exprs) {
   for (int i = 0; i < exprs->length(); ++i) {
     VisitForValue(exprs->at(i));
   }
 }
 
 
 void AstGraphBuilder::VisitForValue(Expression* expr) {
-  AstValueContext for_value(this, expr->id());
+  AstValueContext for_value(this);
   if (!HasStackOverflow()) {
     expr->Accept(this);
   }
 }
 
 
 void AstGraphBuilder::VisitForEffect(Expression* expr) {
-  AstEffectContext for_effect(this, expr->id());
+  AstEffectContext for_effect(this);
   if (!HasStackOverflow()) {
     expr->Accept(this);
   }
 }
 
 
 void AstGraphBuilder::VisitForTest(Expression* expr) {
-  AstTestContext for_condition(this, expr->id());
+  AstTestContext for_condition(this);
   if (!HasStackOverflow()) {
     expr->Accept(this);
   }
 }
 
 
 void AstGraphBuilder::VisitVariableDeclaration(VariableDeclaration* decl) {
   Variable* variable = decl->proxy()->var();
   VariableMode mode = decl->mode();
   bool hole_init = mode == CONST || mode == CONST_LEGACY || mode == LET;
@@ skipping 716 matching lines @@
       case VARIABLE: {
         Variable* variable = expr->target()->AsVariableProxy()->var();
         old_value = BuildVariableLoad(variable, expr->target()->id());
         break;
       }
       case NAMED_PROPERTY: {
         Node* object = environment()->Top();
         PrintableUnique<Name> name =
             MakeUnique(property->key()->AsLiteral()->AsPropertyName());
         old_value = NewNode(javascript()->LoadNamed(name), object);
-        BuildLazyBailoutWithPushedNode(old_value, property->LoadId());
+        BuildLazyBailout(old_value, property->LoadId(), PUSH_OUTPUT);
         break;
       }
       case KEYED_PROPERTY: {
         Node* key = environment()->Top();
         Node* object = environment()->Peek(1);
         old_value = NewNode(javascript()->LoadProperty(), object, key);
-        BuildLazyBailoutWithPushedNode(old_value, property->LoadId());
+        BuildLazyBailout(old_value, property->LoadId(), PUSH_OUTPUT);
         break;
       }
     }
     environment()->Push(old_value);
     VisitForValue(expr->value());
     Node* right = environment()->Pop();
     Node* left = environment()->Pop();
     Node* value = BuildBinaryOp(left, right, expr->binary_op());
     environment()->Push(value);
     BuildLazyBailout(value, expr->binary_operation()->id());
@@ skipping 58 matching lines @@
     PrintableUnique<Name> name =
         MakeUnique(expr->key()->AsLiteral()->AsPropertyName());
     value = NewNode(javascript()->LoadNamed(name), object);
   } else {
     VisitForValue(expr->obj());
     VisitForValue(expr->key());
     Node* key = environment()->Pop();
     Node* object = environment()->Pop();
     value = NewNode(javascript()->LoadProperty(), object, key);
   }
-  ast_context()->ProduceValueWithLazyBailout(value);
+  BuildLazyBailout(value, expr->id(), StateCombineFromAstContext());
+  ast_context()->ProduceValue(value);
 }
 
 
 void AstGraphBuilder::VisitCall(Call* expr) {
   Expression* callee = expr->expression();
   Call::CallType call_type = expr->GetCallType(isolate());
 
   // Prepare the callee and the receiver to the function call. This depends on
   // the semantics of the underlying call type.
   CallFunctionFlags flags = NO_CALL_FUNCTION_FLAGS;
@@ skipping 23 matching lines @@
       Node* object = environment()->Top();
       if (property->key()->IsPropertyName()) {
         PrintableUnique<Name> name =
             MakeUnique(property->key()->AsLiteral()->AsPropertyName());
         callee_value = NewNode(javascript()->LoadNamed(name), object);
       } else {
         VisitForValue(property->key());
         Node* key = environment()->Pop();
         callee_value = NewNode(javascript()->LoadProperty(), object, key);
       }
-      BuildLazyBailoutWithPushedNode(callee_value, property->LoadId());
+      BuildLazyBailout(callee_value, property->LoadId(), PUSH_OUTPUT);
       receiver_value = environment()->Pop();
       // Note that a PROPERTY_CALL requires the receiver to be wrapped into an
       // object for sloppy callees. This could also be modeled explicitly here,
       // thereby obsoleting the need for a flag to the call operator.
       flags = CALL_AS_METHOD;
       break;
     }
     case Call::POSSIBLY_EVAL_CALL:
       possibly_eval = true;
     // Fall through.
@@ skipping 34 matching lines @@
     Node* new_receiver = NewNode(common()->Projection(1), pair);
 
     // Patch callee and receiver on the environment.
     environment()->Poke(arg_count + 1, new_callee);
     environment()->Poke(arg_count + 0, new_receiver);
   }
 
   // Create node to perform the function call.
   Operator* call = javascript()->Call(args->length() + 2, flags);
   Node* value = ProcessArguments(call, args->length() + 2);
-  ast_context()->ProduceValueWithLazyBailout(value);
+  BuildLazyBailout(value, expr->id(), StateCombineFromAstContext());
+  ast_context()->ProduceValue(value);
 }
 
 
 void AstGraphBuilder::VisitCallNew(CallNew* expr) {
   VisitForValue(expr->expression());
 
   // Evaluate all arguments to the construct call.
   ZoneList<Expression*>* args = expr->arguments();
   VisitForValues(args);
 
   // Create node to perform the construct call.
   Operator* call = javascript()->CallNew(args->length() + 1);
   Node* value = ProcessArguments(call, args->length() + 1);
-  ast_context()->ProduceValueWithLazyBailout(value);
+  BuildLazyBailout(value, expr->id(), StateCombineFromAstContext());
+  ast_context()->ProduceValue(value);
 }
 
 
 void AstGraphBuilder::VisitCallJSRuntime(CallRuntime* expr) {
   Handle<String> name = expr->name();
 
   // The callee and the receiver both have to be pushed onto the operand stack
   // before arguments are being evaluated.
   CallFunctionFlags flags = NO_CALL_FUNCTION_FLAGS;
   Node* receiver_value = BuildLoadBuiltinsObject();
   PrintableUnique<String> unique = MakeUnique(name);
   Node* callee_value = NewNode(javascript()->LoadNamed(unique), receiver_value);
   environment()->Push(callee_value);
   // TODO(jarin): Find/create a bailout id to deoptimize to (crankshaft
   // refuses to optimize functions with jsruntime calls).
   BuildLazyBailout(callee_value, BailoutId::None());
   environment()->Push(receiver_value);
 
   // Evaluate all arguments to the JS runtime call.
   ZoneList<Expression*>* args = expr->arguments();
   VisitForValues(args);
 
   // Create node to perform the JS runtime call.
   Operator* call = javascript()->Call(args->length() + 2, flags);
   Node* value = ProcessArguments(call, args->length() + 2);
-  ast_context()->ProduceValueWithLazyBailout(value);
+  BuildLazyBailout(value, expr->id(), StateCombineFromAstContext());
+  ast_context()->ProduceValue(value);
 }
 
 
 void AstGraphBuilder::VisitCallRuntime(CallRuntime* expr) {
   const Runtime::Function* function = expr->function();
 
   // Handle calls to runtime functions implemented in JavaScript separately as
   // the call follows JavaScript ABI and the callee is statically unknown.
   if (expr->is_jsruntime()) {
     DCHECK(function == NULL && expr->name()->length() > 0);
     return VisitCallJSRuntime(expr);
   }
 
   // Evaluate all arguments to the runtime call.
   ZoneList<Expression*>* args = expr->arguments();
   VisitForValues(args);
 
   // Create node to perform the runtime call.
   Runtime::FunctionId functionId = function->function_id;
   Operator* call = javascript()->Runtime(functionId, args->length());
   Node* value = ProcessArguments(call, args->length());
-  ast_context()->ProduceValueWithLazyBailout(value);
+  BuildLazyBailout(value, expr->id(), StateCombineFromAstContext());
+  ast_context()->ProduceValue(value);
 }
 
 
 void AstGraphBuilder::VisitUnaryOperation(UnaryOperation* expr) {
   switch (expr->op()) {
     case Token::DELETE:
       return VisitDelete(expr);
     case Token::VOID:
       return VisitVoid(expr);
     case Token::TYPEOF:
@@ skipping 26 matching lines @@
       old_value = BuildVariableLoad(variable, expr->expression()->id());
       stack_depth = 0;
       break;
     }
     case NAMED_PROPERTY: {
       VisitForValue(property->obj());
       Node* object = environment()->Top();
       PrintableUnique<Name> name =
           MakeUnique(property->key()->AsLiteral()->AsPropertyName());
       old_value = NewNode(javascript()->LoadNamed(name), object);
-      BuildLazyBailoutWithPushedNode(old_value, property->LoadId());
+      BuildLazyBailout(old_value, property->LoadId(), PUSH_OUTPUT);
       stack_depth = 1;
       break;
     }
     case KEYED_PROPERTY: {
       VisitForValue(property->obj());
       VisitForValue(property->key());
       Node* key = environment()->Top();
       Node* object = environment()->Peek(1);
       old_value = NewNode(javascript()->LoadProperty(), object, key);
-      BuildLazyBailoutWithPushedNode(old_value, property->LoadId());
+      BuildLazyBailout(old_value, property->LoadId(), PUSH_OUTPUT);
       stack_depth = 2;
       break;
     }
   }
 
   // Convert old value into a number.
   old_value = NewNode(javascript()->ToNumber(), old_value);
 
   // Save result for postfix expressions at correct stack depth.
   if (is_postfix) environment()->Poke(stack_depth, old_value);
@@ skipping 43 matching lines @@
       return VisitComma(expr);
     case Token::OR:
     case Token::AND:
       return VisitLogicalExpression(expr);
     default: {
       VisitForValue(expr->left());
       VisitForValue(expr->right());
       Node* right = environment()->Pop();
       Node* left = environment()->Pop();
       Node* value = BuildBinaryOp(left, right, expr->op());
-      ast_context()->ProduceValueWithLazyBailout(value);
+      BuildLazyBailout(value, expr->id(), StateCombineFromAstContext());
+      ast_context()->ProduceValue(value);
     }
   }
 }
 
 
 void AstGraphBuilder::VisitCompareOperation(CompareOperation* expr) {
   Operator* op;
   switch (expr->op()) {
     case Token::EQ:
       op = javascript()->Equal();
@@ skipping 259 matching lines @@
                                          ContextualMode contextual_mode) {
   Node* the_hole = jsgraph()->TheHoleConstant();
   VariableMode mode = variable->mode();
   switch (variable->location()) {
     case Variable::UNALLOCATED: {
       // Global var, const, or let variable.
       Node* global = BuildLoadGlobalObject();
       PrintableUnique<Name> name = MakeUnique(variable->name());
       Operator* op = javascript()->LoadNamed(name, contextual_mode);
       Node* node = NewNode(op, global);
-      BuildLazyBailoutWithPushedNode(node, bailout_id);
+      BuildLazyBailout(node, bailout_id, PUSH_OUTPUT);
       return node;
     }
     case Variable::PARAMETER:
     case Variable::LOCAL: {
       // Local var, const, or let variable.
       Node* value = environment()->Lookup(variable);
       if (mode == CONST_LEGACY) {
         // Perform check for uninitialized legacy const variables.
         if (value->op() == the_hole->op()) {
           value = jsgraph()->UndefinedConstant();
@@ skipping 232 matching lines @@
       js_op = javascript()->Modulus();
       break;
     default:
       UNREACHABLE();
       js_op = NULL;
   }
   return NewNode(js_op, left, right);
 }
 
 
-void AstGraphBuilder::BuildLazyBailout(Node* node, BailoutId ast_id) {
+void AstGraphBuilder::BuildLazyBailout(Node* node, BailoutId ast_id,
+                                       OutputFrameStateCombine combine) {
   if (OperatorProperties::CanLazilyDeoptimize(node->op())) {
     // The deopting node should have an outgoing control dependency.
     DCHECK(environment()->GetControlDependency() == node);
 
+    if (combine == PUSH_OUTPUT) {
+      environment()->Push(node);
+    }
+
     StructuredGraphBuilder::Environment* continuation_env = environment();
     // Create environment for the deoptimization block, and build the block.
     StructuredGraphBuilder::Environment* deopt_env =
         CopyEnvironment(continuation_env);
     set_environment(deopt_env);
 
     NewNode(common()->LazyDeoptimization());
 
     // TODO(jarin) If ast_id.IsNone(), perhaps we should generate an empty
     // deopt block and make sure there is no patch entry for this (so
     // that the deoptimizer dies when trying to deoptimize here).
 
     Node* state_node = environment()->Checkpoint(ast_id);
 
     Node* deoptimize_node = NewNode(common()->Deoptimize(), state_node);
 
     UpdateControlDependencyToLeaveFunction(deoptimize_node);
 
     // Continue with the original environment.
     set_environment(continuation_env);
 
+    if (combine == PUSH_OUTPUT) {
+      environment()->Pop();
+    }
+
     NewNode(common()->Continuation());
   }
 }
 
 
-void AstGraphBuilder::BuildLazyBailoutWithPushedNode(Node* node,
-                                                     BailoutId ast_id) {
-  environment()->Push(node);
-  BuildLazyBailout(node, ast_id);
-  environment()->Pop();
+AstGraphBuilder::OutputFrameStateCombine
+AstGraphBuilder::StateCombineFromAstContext() {
+  return ast_context()->IsEffect() ? IGNORE_OUTPUT : PUSH_OUTPUT;
 }
 }
 }
 }  // namespace v8::internal::compiler