[llvm] [VPlan] Explicitly reassociate header mask in logical and (PR #180898)

[Ramkumar Ramachandra via llvm-commits]

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@@ -2758,12 +2770,14 @@ void VPlanTransforms::optimize(VPlan &Plan) {
   RUN_VPLAN_PASS(removeRedundantCanonicalIVs, Plan);
   RUN_VPLAN_PASS(removeRedundantInductionCasts, Plan);
 
+  RUN_VPLAN_PASS(reassociateHeaderMask, Plan);
   RUN_VPLAN_PASS(simplifyRecipes, Plan);
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artagnon wrote:

I would have expected reassociateHeaderMask to be called _after_ simplifyRecipes, for functional equivalence?

https://github.com/llvm/llvm-project/pull/180898