[Hexagon] Stop pmpy recognition when shift conversion fails

The conversion of shifts from right shifts to left shifts may fail.
In such case, the pmpy recognition cannot proceed.

llvm-svn: 305289

1 files changed, 2 insertions, 1 deletions

diff --git a/llvm/lib/Target/Hexagon/HexagonLoopIdiomRecognition.cpp b/llvm/lib/Target/Hexagon/HexagonLoopIdiomRecognition.cpp
index b748b58bc0a..f82ad6cb3da 100644
--- a/llvm/lib/Target/Hexagon/HexagonLoopIdiomRecognition.cpp
+++ b/llvm/lib/Target/Hexagon/HexagonLoopIdiomRecognition.cpp
@@ -1744,7 +1744,8 @@ bool PolynomialMultiplyRecognize::recognize() {
     // wide as the target's pmpy instruction.
     if (!promoteTypes(LoopB, ExitB))
       return false;
-    convertShiftsToLeft(LoopB, ExitB, IterCount);
+    if (!convertShiftsToLeft(LoopB, ExitB, IterCount))
+      return false;
     cleanupLoopBody(LoopB);
   }