fix PR9215, preventing -reassociate from clearing nsw/nuw when
it swaps the LHS/RHS of a single binop.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125700 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/Reassociate.cpp b/lib/Transforms/Scalar/Reassociate.cpp
index 5df6f37..e093b52 100644
--- a/lib/Transforms/Scalar/Reassociate.cpp
+++ b/lib/Transforms/Scalar/Reassociate.cpp
@@ -348,9 +348,10 @@
I->setOperand(0, Ops[i].Op);
I->setOperand(1, Ops[i+1].Op);
- // Conservatively clear all the optional flags, which may not hold
- // after the reassociation.
- I->clearSubclassOptionalData();
+ // Clear all the optional flags, which may not hold after the
+ // reassociation if the expression involved more than just this operation.
+ if (Ops.size() != 2)
+ I->clearSubclassOptionalData();
DEBUG(dbgs() << "TO: " << *I << '\n');
MadeChange = true;