Fix indvars to not assume that a loop with a single unique exit
block has a single unique exiting block.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75579 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/IndVarSimplify.cpp b/lib/Transforms/Scalar/IndVarSimplify.cpp
index 365589d..911545d 100644
--- a/lib/Transforms/Scalar/IndVarSimplify.cpp
+++ b/lib/Transforms/Scalar/IndVarSimplify.cpp
@@ -281,17 +281,15 @@
// If this instruction is dead now, delete it.
RecursivelyDeleteTriviallyDeadInstructions(Inst);
- // If we're inserting code into the exit block rather than the
- // preheader, we can (and have to) remove the PHI entirely.
- // This is safe, because the NewVal won't be variant
- // in the loop, so we don't need an LCSSA phi node anymore.
- if (ExitBlocks.size() == 1) {
+ if (NumPreds == 1) {
+ // Completely replace a single-pred PHI. This is safe, because the
+ // NewVal won't be variant in the loop, so we don't need an LCSSA phi
+ // node anymore.
PN->replaceAllUsesWith(ExitVal);
RecursivelyDeleteTriviallyDeadInstructions(PN);
- break;
}
}
- if (ExitBlocks.size() != 1) {
+ if (NumPreds != 1) {
// Clone the PHI and delete the original one. This lets IVUsers and
// any other maps purge the original user from their records.
PHINode *NewPN = PN->clone(*Context);