Fix polarity of a CFG check in machine verifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@88704 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/MachineVerifier.cpp b/lib/CodeGen/MachineVerifier.cpp
index 99812e0..c056d1c 100644
--- a/lib/CodeGen/MachineVerifier.cpp
+++ b/lib/CodeGen/MachineVerifier.cpp
@@ -287,7 +287,18 @@
markReachable(&MF->front());
}
-void MachineVerifier::visitMachineBasicBlockBefore(const MachineBasicBlock *MBB) {
+// Does iterator point to a and b as the first two elements?
+bool matchPair(MachineBasicBlock::const_succ_iterator i,
+ const MachineBasicBlock *a, const MachineBasicBlock *b) {
+ if (*i == a)
+ return *++i == b;
+ if (*i == b)
+ return *++i == a;
+ return false;
+}
+
+void
+MachineVerifier::visitMachineBasicBlockBefore(const MachineBasicBlock *MBB) {
const TargetInstrInfo *TII = MF->getTarget().getInstrInfo();
// Start with minimal CFG sanity checks.
@@ -379,8 +390,7 @@
} if (MBB->succ_size() != 2) {
report("MBB exits via conditional branch/fall-through but doesn't have "
"exactly two CFG successors!", MBB);
- } else if ((MBB->succ_begin()[0] == TBB && MBB->succ_end()[1] == MBBI) ||
- (MBB->succ_begin()[1] == TBB && MBB->succ_end()[0] == MBBI)) {
+ } else if (!matchPair(MBB->succ_begin(), TBB, MBBI)) {
report("MBB exits via conditional branch/fall-through but the CFG "
"successors don't match the actual successors!", MBB);
}
@@ -400,8 +410,7 @@
if (MBB->succ_size() != 2) {
report("MBB exits via conditional branch/branch but doesn't have "
"exactly two CFG successors!", MBB);
- } else if ((MBB->succ_begin()[0] == TBB && MBB->succ_end()[1] == FBB) ||
- (MBB->succ_begin()[1] == TBB && MBB->succ_end()[0] == FBB)) {
+ } else if (!matchPair(MBB->succ_begin(), TBB, FBB)) {
report("MBB exits via conditional branch/branch but the CFG "
"successors don't match the actual successors!", MBB);
}