[PredicateInfo] Do not process unreachable operands.

Summary: We should excluded unreachable operands from processing as their DFS visitation order is undefined. When `renameUses` function sorts `OpsToRename` (https://fburl.com/d2wubn60), the comparator assumes that the parent block of the operand has a corresponding dominator tree node. This is not the case for unreachable operands and crashes the compiler.

Reviewers: dberlin, mgrang, davide

Subscribers: efriedma, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D61154

llvm-svn: 360796

1 files changed, 2 insertions, 1 deletions

diff --git a/llvm/lib/Transforms/Utils/PredicateInfo.cpp b/llvm/lib/Transforms/Utils/PredicateInfo.cpp
index 6f041ace6d1..bdf24d80bd1 100644
--- a/llvm/lib/Transforms/Utils/PredicateInfo.cpp
+++ b/llvm/lib/Transforms/Utils/PredicateInfo.cpp
@@ -473,7 +473,8 @@ void PredicateInfo::buildPredicateInfo() {
   }
   for (auto &Assume : AC.assumptions()) {
     if (auto *II = dyn_cast_or_null<IntrinsicInst>(Assume))
-      processAssume(II, II->getParent(), OpsToRename);
+      if (DT.isReachableFromEntry(II->getParent()))
+        processAssume(II, II->getParent(), OpsToRename);
   }
   // Now rename all our operations.
   renameUses(OpsToRename);