[turbofan] Connect non-terminating loops via Terminate.

src/compiler/verifier.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/verifier.h"
 
 #include <algorithm>
 #include <deque>
 #include <queue>
 #include <sstream>
@@ skipping 150 matching lines @@
   if (node->op()->ValueOutputCount() > 1) {
     for (Edge edge : node->use_edges()) {
       Node* use = edge.from();
       CHECK(!NodeProperties::IsValueEdge(edge) ||
             use->opcode() == IrOpcode::kProjection ||
             use->opcode() == IrOpcode::kParameter);
     }
   }
 
   switch (node->opcode()) {
-    case IrOpcode::kAlways:
-      // Always has no inputs.
-      CHECK_EQ(0, input_count);
-      // Always uses are Branch.
-      for (auto use : node->uses()) {
-        CHECK(use->opcode() == IrOpcode::kBranch);
-      }
-      // Type is boolean.
-      CheckUpperIs(node, Type::Boolean());
-      break;
     case IrOpcode::kStart:
       // Start has no inputs.
       CHECK_EQ(0, input_count);
       // Type is a tuple.
       // TODO(rossberg): Multiple outputs are currently typed as Internal.
       CheckUpperIs(node, Type::Internal());
       break;
     case IrOpcode::kEnd:
       // End has no outputs.
       CHECK(node->op()->ValueOutputCount() == 0);
@@ skipping 95 matching lines @@
     case IrOpcode::kReturn:
       // TODO(rossberg): check successor is End
       // Type is empty.
       CheckNotTyped(node);
       break;
     case IrOpcode::kThrow:
       // TODO(rossberg): what are the constraints on these?
       // Type is empty.
       CheckNotTyped(node);
       break;
+    case IrOpcode::kTerminate:
+      CHECK_EQ(IrOpcode::kLoop,
+               NodeProperties::GetControlInput(node)->opcode());
+      // Type is empty.
+      CheckNotTyped(node);
+      CHECK_EQ(1, control_count);
+      CHECK_EQ(1, effect_count);
+      CHECK_EQ(2, input_count);
+      break;
     case IrOpcode::kOsrNormalEntry:
     case IrOpcode::kOsrLoopEntry:
       // Osr entries have
       CHECK_EQ(1, effect_count);
       CHECK_EQ(1, control_count);
       // Type is empty.
       CheckNotTyped(node);
       break;
 
     // Common operators
@@ skipping 791 matching lines @@
     // Check inputs for all nodes in the block.
     for (size_t i = 0; i < block->NodeCount(); i++) {
       Node* node = block->NodeAt(i);
       CheckInputsDominate(schedule, block, node, static_cast<int>(i) - 1);
     }
   }
 }
 }
 }
 }  // namespace v8::internal::compiler