[llvm] [VPlan] Handle canonical VPWidenIntOrFpInduction in branch-condition simplification (PR #153539)

[Mel Chen via llvm-commits]

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@@ -1498,10 +1498,21 @@ static bool simplifyBranchConditionForVFAndUF(VPlan &Plan, ElementCount BestVF,
   // the region, otherwise replace the terminator controlling the latch with
   // (BranchOnCond true).
   auto *Header = cast<VPBasicBlock>(VectorRegion->getEntry());
-  if (all_of(Header->phis(),
-             IsaPred<VPCanonicalIVPHIRecipe, VPEVLBasedIVPHIRecipe,
-                     VPFirstOrderRecurrencePHIRecipe, VPPhi>)) {
+  if (all_of(Header->phis(), [](VPRecipeBase &Phi) {
+        if (auto *R = dyn_cast<VPWidenIntOrFpInductionRecipe>(&Phi))
+          return R->isCanonical();
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Mel-Chen wrote:

Could we simplify it if it’s not canonical? If so, could we mark a TODO comment?

https://github.com/llvm/llvm-project/pull/153539