[turbofan] Connect non-terminating loops via Terminate.

test/unittests/compiler/control-reducer-unittest.cc

 // Copyright 2015 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/control-reducer.h"
 #include "src/compiler/diamond.h"
 #include "src/compiler/graph-visualizer.h"
 #include "src/compiler/js-graph.h"
 #include "src/compiler/js-operator.h"
 #include "src/compiler/machine-operator.h"
@@ skipping 39 matching lines @@
   }
 
   JSGraph* jsgraph() { return &jsgraph_; }
 };
 
 
 TEST_F(ControlReducerTest, NonTerminatingLoop) {
   Node* loop = graph()->NewNode(common()->Loop(2), graph()->start());
   loop->AppendInput(graph()->zone(), loop);
   ReduceGraph();
-  Capture<Node*> branch;
   EXPECT_THAT(
       graph()->end(),
-      IsEnd(IsMerge(
-          graph()->start(),
-          IsReturn(IsUndefinedConstant(), graph()->start(),
-                   IsIfFalse(
-                       AllOf(CaptureEq(&branch),
-                             IsBranch(IsAlways(),
-                                      AllOf(loop, IsLoop(graph()->start(),
-                                                         IsIfTrue(CaptureEq(
-                                                             &branch)))))))))));
+      IsEnd(IsMerge(graph()->start(),
+                    IsTerminate(graph()->start(),
+                                AllOf(loop, IsLoop(graph()->start(), loop))))));
 }
 
 
 TEST_F(ControlReducerTest, NonTerminatingLoopWithEffectPhi) {
   Node* loop = graph()->NewNode(common()->Loop(2), graph()->start());
   loop->AppendInput(graph()->zone(), loop);
   Node* ephi = graph()->NewNode(common()->EffectPhi(2), graph()->start());
   ephi->AppendInput(graph()->zone(), ephi);
   ephi->AppendInput(graph()->zone(), loop);
   ReduceGraph();
-  Capture<Node*> branch;
   EXPECT_THAT(
       graph()->end(),
       IsEnd(IsMerge(
           graph()->start(),
-          IsReturn(IsUndefinedConstant(),
-                   AllOf(ephi, IsEffectPhi(graph()->start(), ephi, loop)),
-                   IsIfFalse(
-                       AllOf(CaptureEq(&branch),
-                             IsBranch(IsAlways(),
-                                      AllOf(loop, IsLoop(graph()->start(),
-                                                         IsIfTrue(CaptureEq(
-                                                             &branch)))))))))));
+          IsTerminate(AllOf(ephi, IsEffectPhi(graph()->start(), ephi, loop)),
+                      AllOf(loop, IsLoop(graph()->start(), loop))))));
 }
 
 
 TEST_F(ControlReducerTest, NonTerminatingLoopWithTwoEffectPhis) {
   Node* loop = graph()->NewNode(common()->Loop(2), graph()->start());
   loop->AppendInput(graph()->zone(), loop);
   Node* ephi1 = graph()->NewNode(common()->EffectPhi(2), graph()->start());
   ephi1->AppendInput(graph()->zone(), ephi1);
   ephi1->AppendInput(graph()->zone(), loop);
   Node* ephi2 = graph()->NewNode(common()->EffectPhi(2), graph()->start());
   ephi2->AppendInput(graph()->zone(), ephi2);
   ephi2->AppendInput(graph()->zone(), loop);
   ReduceGraph();
-  Capture<Node*> branch;
   EXPECT_THAT(
       graph()->end(),
       IsEnd(IsMerge(
           graph()->start(),
-          IsReturn(
-              IsUndefinedConstant(),
+          IsTerminate(
               IsEffectSet(
                   AllOf(ephi1, IsEffectPhi(graph()->start(), ephi1, loop)),
                   AllOf(ephi2, IsEffectPhi(graph()->start(), ephi2, loop))),
-              IsIfFalse(AllOf(
-                  CaptureEq(&branch),
-                  IsBranch(
-                      IsAlways(),
-                      AllOf(loop, IsLoop(graph()->start(),
-                                         IsIfTrue(CaptureEq(&branch)))))))))));
+              AllOf(loop, IsLoop(graph()->start(), loop))))));
 }
 
 
 TEST_F(ControlReducerTest, NonTerminatingLoopWithDeadEnd) {
   Node* loop = graph()->NewNode(common()->Loop(2), graph()->start());
   loop->AppendInput(graph()->zone(), loop);
   graph()->end()->ReplaceInput(0, graph()->NewNode(common()->Dead()));
   ReduceGraph();
-  Capture<Node*> branch;
-  EXPECT_THAT(
-      graph()->end(),
-      IsEnd(IsReturn(
-          IsUndefinedConstant(), graph()->start(),
-          IsIfFalse(AllOf(
-              CaptureEq(&branch),
-              IsBranch(IsAlways(),
-                       AllOf(loop, IsLoop(graph()->start(),
-                                          IsIfTrue(CaptureEq(&branch))))))))));
+  EXPECT_THAT(graph()->end(),
+              IsEnd(IsTerminate(graph()->start(),
+                                AllOf(loop, IsLoop(graph()->start(), loop)))));
 }
 
 
 TEST_F(ControlReducerTest, PhiAsInputToBranch_true) {
   Node* p0 = Parameter(0);
   Node* branch1 = graph()->NewNode(common()->Branch(), p0, graph()->start());
   Node* if_true1 = graph()->NewNode(common()->IfTrue(), branch1);
   Node* if_false1 = graph()->NewNode(common()->IfFalse(), branch1);
   Node* merge1 = graph()->NewNode(common()->Merge(2), if_true1, if_false1);
   Node* phi1 = graph()->NewNode(common()->Phi(kMachInt32, 2),
@@ skipping 193 matching lines @@
                    IsSelect(kType, p0, IsInt32Constant(1), IsInt32Constant(2)),
                    IsSelect(kType, p0, IsInt32Constant(2), IsInt32Constant(3))),
                graph()->start(), graph()->start()));
   EXPECT_THAT(graph()->end(), IsEnd(ret));
 }
 
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8