[SCCP][PredicateInfo] Do not predicate argument of lifetime intrinsic

Replacing the argument with a no-op bitcast violates a verifier
constraint, even if only temporarily. Any replacement based on it
would result in a violation even after the copy has been removed.

Fixes https://github.com/llvm/llvm-project/issues/153013.

1 files changed, 5 insertions, 0 deletions

diff --git a/llvm/lib/Transforms/Utils/PredicateInfo.cpp b/llvm/lib/Transforms/Utils/PredicateInfo.cpp
index 38a312a..13c7ad2 100644
--- a/llvm/lib/Transforms/Utils/PredicateInfo.cpp
+++ b/llvm/lib/Transforms/Utils/PredicateInfo.cpp
@@ -291,6 +291,11 @@ void PredicateInfoBuilder::convertUsesToDFSOrdered(
     Value *Op, SmallVectorImpl<ValueDFS> &DFSOrderedSet) {
   for (auto &U : Op->uses()) {
     if (auto *I = dyn_cast<Instruction>(U.getUser())) {
+      // Lifetime intrinsics must work directly on alloca, do not replace them
+      // with a predicated copy.
+      if (I->isLifetimeStartOrEnd())
+        continue;
+
       ValueDFS VD;
       // Put the phi node uses in the incoming block.
       BasicBlock *IBlock;