[Constants] don't die processing non-ConstantInt GEP indices in isGEPWithNoNotionalOverIndexing() (PR31262)

This should fix:
https://llvm.org/bugs/show_bug.cgi?id=31262

llvm-svn: 289401

1 files changed, 8 insertions, 6 deletions

diff --git a/llvm/lib/IR/Constants.cpp b/llvm/lib/IR/Constants.cpp
index 6a6820234a0..a3db1525931 100644
--- a/llvm/lib/IR/Constants.cpp
+++ b/llvm/lib/IR/Constants.cpp
@@ -1071,13 +1071,15 @@ bool ConstantExpr::isGEPWithNoNotionalOverIndexing() const {
   gep_type_iterator GEPI = gep_type_begin(this), E = gep_type_end(this);
   User::const_op_iterator OI = std::next(this->op_begin());
 
-  // The remaining indices must be compile-time known integers within the
-  // bounds of the corresponding notional static array types.
+  // The remaining indices may be compile-time known integers within the bounds
+  // of the corresponding notional static array types.
   for (; GEPI != E; ++GEPI, ++OI) {
-    ConstantInt *CI = dyn_cast<ConstantInt>(*OI);
-    if (GEPI.isBoundedSequential() &&
-        (CI->getValue().getActiveBits() > 64 ||
-         CI->getZExtValue() >= GEPI.getSequentialNumElements()))
+    if (isa<UndefValue>(*OI))
+      continue;
+    auto *CI = dyn_cast<ConstantInt>(*OI);
+    if (!CI || (GEPI.isBoundedSequential() &&
+                (CI->getValue().getActiveBits() > 64 ||
+                 CI->getZExtValue() >= GEPI.getSequentialNumElements())))
       return false;
   }