1 files changed, 5 insertions, 2 deletions
diff --git a/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp b/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp
index 9996ebc2e7..497c0b49ab 100644
--- a/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp
+++ b/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp
@@ -203,8 +203,11 @@ Instruction *InstCombiner::visitMul(BinaryOperator &I) {
       Value *X;
       Constant *C1;
       if (match(Op0, m_OneUse(m_Add(m_Value(X), m_Constant(C1))))) {
-        Value *Add = Builder->CreateMul(X, Op1);
-        return BinaryOperator::CreateAdd(Add, Builder->CreateMul(C1, Op1));
+        Value *Mul = Builder->CreateMul(C1, Op1);
+        // Only go forward with the transform if C1*CI simplifies to a tidier
+        // constant.
+        if (!match(Mul, m_Mul(m_Value(), m_Value())))
+          return BinaryOperator::CreateAdd(Builder->CreateMul(X, Op1), Mul);
       }
     }
   }