[turbofan] Make IfException projections consume effects.

src/compiler/graph-reducer.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 <functional>
 #include <limits>
 
 #include "src/compiler/graph.h"
 #include "src/compiler/graph-reducer.h"
 #include "src/compiler/node.h"
@@ skipping 213 matching lines @@
 
   // Requires distinguishing between value, effect and control edges.
   for (Edge edge : node->use_edges()) {
     Node* user = edge.from();
     if (NodeProperties::IsControlEdge(edge)) {
       if (user->opcode() == IrOpcode::kIfSuccess) {
         Replace(user, control);
       } else if (user->opcode() == IrOpcode::kIfException) {
         for (Edge e : user->use_edges()) {
           if (NodeProperties::IsValueEdge(e)) e.UpdateTo(dead_value_);
+          if (NodeProperties::IsEffectEdge(e)) e.UpdateTo(graph()->start());
           if (NodeProperties::IsControlEdge(e)) e.UpdateTo(dead_control_);
         }
-        user->Kill();
+        edge.UpdateTo(user);
       } else {
         UNREACHABLE();
       }
     } else if (NodeProperties::IsEffectEdge(edge)) {
       DCHECK_NOT_NULL(effect);
       edge.UpdateTo(effect);
       Revisit(user);
     } else {
+      DCHECK_NOT_NULL(value);
       edge.UpdateTo(value);
       Revisit(user);
     }
   }
 }
 
 
 void GraphReducer::Pop() {
   Node* node = stack_.top().node;
   state_.Set(node, State::kVisited);
@@ skipping 18 matching lines @@
 void GraphReducer::Revisit(Node* node) {
   if (state_.Get(node) == State::kVisited) {
     state_.Set(node, State::kRevisit);
     revisit_.push(node);
   }
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8