[debug] use catch prediction flag for promise rejections.

src/ast/ast-numbering.cc

 // Copyright 2012 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/ast/ast-numbering.h"
 
 #include "src/ast/ast.h"
 #include "src/ast/scopes.h"
 
 namespace v8 {
 namespace internal {
 
 class AstNumberingVisitor final : public AstVisitor<AstNumberingVisitor> {
  public:
   AstNumberingVisitor(Isolate* isolate, Zone* zone)
       : isolate_(isolate),
         zone_(zone),
         next_id_(BailoutId::FirstUsable().ToInt()),
         yield_count_(0),
         properties_(zone),
         slot_cache_(zone),
         dont_optimize_reason_(kNoReason),
-        catch_predicted_(false) {
+        catch_prediction_(HandlerTable::UNCAUGHT) {
     InitializeAstVisitor(isolate);
   }
 
   bool Renumber(FunctionLiteral* node);
 
  private:
 // AST node visitor interface.
 #define DEFINE_VISIT(type) void Visit##type(type* node);
   AST_NODE_LIST(DEFINE_VISIT)
 #undef DEFINE_VISIT
@@ skipping 39 matching lines @@
   BailoutReason dont_optimize_reason() const { return dont_optimize_reason_; }
 
   Isolate* isolate_;
   Zone* zone_;
   int next_id_;
   int yield_count_;
   AstProperties properties_;
   // The slot cache allows us to reuse certain feedback vector slots.
   FeedbackVectorSlotCache slot_cache_;
   BailoutReason dont_optimize_reason_;
-  bool catch_predicted_;
+  HandlerTable::CatchPrediction catch_prediction_;
 
   DEFINE_AST_VISITOR_SUBCLASS_MEMBERS();
   DISALLOW_COPY_AND_ASSIGN(AstNumberingVisitor);
 };
 
 
 void AstNumberingVisitor::VisitVariableDeclaration(VariableDeclaration* node) {
   IncrementNodeCount();
   VisitVariableProxy(node->proxy());
 }
@@ skipping 191 matching lines @@
   Visit(node->cond());
   Visit(node->body());
   node->set_yield_count(yield_count_ - node->first_yield_id());
 }
 
 
 void AstNumberingVisitor::VisitTryCatchStatement(TryCatchStatement* node) {
   IncrementNodeCount();
   DisableCrankshaft(kTryCatchStatement);
   {
-    const bool old_catch_predicted = catch_predicted_;
-    // If the node's clear_pending_message flag is unset, we assume that the
-    // catch block is a ReThrow and hence predict uncaught (unless caught by
-    // outer handlers).  Otherwise, we predict caught.
-    const bool not_rethrow = node->clear_pending_message();
-    catch_predicted_ = catch_predicted_ || not_rethrow;
-    node->set_catch_predicted(catch_predicted_);
+    const HandlerTable::CatchPrediction old_prediction = catch_prediction_;
+    // This node uses its own prediction, unless it's "uncaught", in which case
+    // we adopt the prediction of the outer try-block.

[Michael Starzinger, 2016/07/20 09:20:18]

nit: s/outer/surrounding/

+    HandlerTable::CatchPrediction catch_prediction = node->catch_prediction();
+    if (catch_prediction != HandlerTable::UNCAUGHT) {
+      catch_prediction_ = catch_prediction;
+    }
+    node->set_catch_prediction(catch_prediction_);
     Visit(node->try_block());
-    catch_predicted_ = old_catch_predicted;
+    catch_prediction_ = old_prediction;
   }
   Visit(node->catch_block());
 }
 
 
 void AstNumberingVisitor::VisitTryFinallyStatement(TryFinallyStatement* node) {
   IncrementNodeCount();
   DisableCrankshaft(kTryFinallyStatement);
   // We can't know whether the finally block will override ("catch") an
   // exception thrown in the try block, so we just adopt the outer prediction.
-  node->set_catch_predicted(catch_predicted_);
+  node->set_catch_prediction(catch_prediction_);
   Visit(node->try_block());
   Visit(node->finally_block());
 }
 
 
 void AstNumberingVisitor::VisitPropertyReference(Property* node) {
   IncrementNodeCount();
   node->set_base_id(ReserveIdRange(Property::num_ids()));
   Visit(node->key());
   Visit(node->obj());
@@ skipping 267 matching lines @@
 }
 
 
 bool AstNumbering::Renumber(Isolate* isolate, Zone* zone,
                             FunctionLiteral* function) {
   AstNumberingVisitor visitor(isolate, zone);
   return visitor.Renumber(function);
 }
 }  // namespace internal
 }  // namespace v8