[llvm] [SCEV] Return a SCEVUse from getAddExpr and propagate use flags. (PR #220007)

[Nikita Popov via llvm-commits]

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@@ -3002,7 +2985,11 @@ const SCEV *ScalarEvolution::getAddExpr(SmallVectorImpl<SCEVUse> &Ops,
 
   // Okay, it looks like we really DO need an add expr.  Check to see if we
   // already have one, otherwise create a new one.
-  return getOrCreateAddExpr(Ops, ComputeFlags(Ops));
+  assert((UseFlags == SCEV::FlagAnyWrap ||
+          std::is_permutation(OrigOps.begin(), OrigOps.end(), Ops.begin(),
+                              Ops.end())) &&
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nikic wrote:

Do we actually need is_permutation here? Is something reordering the operands (after complexity sorting)?

https://github.com/llvm/llvm-project/pull/220007