[turbofan] Connect non-terminating loops via Terminate.

src/compiler/instruction-selector.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/instruction-selector.h"
 
 #include <limits>
 
 #include "src/base/adapters.h"
 #include "src/compiler/instruction-selector-impl.h"
@@ skipping 456 matching lines @@
     }
     case BasicBlock::kTailCall: {
       DCHECK_EQ(IrOpcode::kTailCall, input->opcode());
       return VisitTailCall(input);
     }
     case BasicBlock::kBranch: {
       DCHECK_EQ(IrOpcode::kBranch, input->opcode());
       BasicBlock* tbranch = block->SuccessorAt(0);
       BasicBlock* fbranch = block->SuccessorAt(1);
       if (tbranch == fbranch) return VisitGoto(tbranch);
-      // Treat special Branch(Always, IfTrue, IfFalse) as Goto(IfTrue).
-      Node* const condition = input->InputAt(0);
-      if (condition->opcode() == IrOpcode::kAlways) return VisitGoto(tbranch);
       return VisitBranch(input, tbranch, fbranch);
     }
     case BasicBlock::kSwitch: {
       DCHECK_EQ(IrOpcode::kSwitch, input->opcode());
       SwitchInfo sw;
       // Last successor must be Default.
       sw.default_branch = block->successors().back();
       DCHECK_EQ(IrOpcode::kIfDefault, sw.default_branch->front()->opcode());
       // All other successors must be cases.
       sw.case_count = block->SuccessorCount() - 1;
@@ skipping 53 matching lines @@
     case IrOpcode::kEnd:
     case IrOpcode::kBranch:
     case IrOpcode::kIfTrue:
     case IrOpcode::kIfFalse:
     case IrOpcode::kIfSuccess:
     case IrOpcode::kSwitch:
     case IrOpcode::kIfValue:
     case IrOpcode::kIfDefault:
     case IrOpcode::kEffectPhi:
     case IrOpcode::kMerge:
+    case IrOpcode::kTerminate:
       // No code needed for these graph artifacts.
       return;
     case IrOpcode::kIfException:
       return MarkAsReference(node), VisitIfException(node);
     case IrOpcode::kFinish:
       return MarkAsReference(node), VisitFinish(node);
     case IrOpcode::kParameter: {
       MachineType type =
           linkage()->GetParameterType(ParameterIndexOf(node->op()));
       MarkAsRepresentation(type, node);
@@ skipping 583 matching lines @@
 MachineOperatorBuilder::Flags
 InstructionSelector::SupportedMachineOperatorFlags() {
   return MachineOperatorBuilder::Flag::kNoFlags;
 }
 
 #endif  // !V8_TURBOFAN_BACKEND
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8