diff --git a/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp b/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp
--- a/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp
@@ -5157,9 +5157,11 @@
   // still being dominated by the input positions.
   BasicBlock::iterator IP = HoistInsertPosition(LowestIP, Inputs);
 
-  // Don't insert instructions before PHI nodes.
+  // Don't insert instructions before PHI nodes and Allocas.
   while (isa<PHINode>(IP)) ++IP;
 
+  while (isa<AllocaInst>(IP)) ++IP;
+
   // Ignore landingpad instructions.
   while (IP->isEHPad()) ++IP;