Verify that phi instructions refer to MBBs in the CFG.

The machine code verifier no longer tolerates phi instructions with noop
operands. All MBBs on a phi instruction must be in the CFG.

llvm-svn: 82448

1 files changed, 8 insertions, 7 deletions

diff --git a/llvm/lib/CodeGen/MachineVerifier.cpp b/llvm/lib/CodeGen/MachineVerifier.cpp
index f43a3703458..b4d6588bf43 100644
--- a/llvm/lib/CodeGen/MachineVerifier.cpp
+++ b/llvm/lib/CodeGen/MachineVerifier.cpp
@@ -592,13 +592,14 @@ MachineVerifier::visitMachineOperand(const MachineOperand *MO, unsigned MONum)
     }
     break;
   }
-    // Can PHI instrs refer to MBBs not in the CFG? X86 and ARM do.
-    // case MachineOperand::MO_MachineBasicBlock:
-    //   if (MI->getOpcode() == TargetInstrInfo::PHI) {
-    //     if (!MO->getMBB()->isSuccessor(MI->getParent()))
-    //       report("PHI operand is not in the CFG", MO, MONum);
-    //   }
-    //   break;
+
+  case MachineOperand::MO_MachineBasicBlock:
+    if (MI->getOpcode() == TargetInstrInfo::PHI) {
+      if (!MO->getMBB()->isSuccessor(MI->getParent()))
+        report("PHI operand is not in the CFG", MO, MONum);
+    }
+    break;
+
   default:
     break;
   }