[llvm] [VPlan] Remove loop region in optimizeForVFAndUF. (PR #108378)

[via llvm-commits]

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@@ -794,11 +794,14 @@ static void simplifyRecipe(VPRecipeBase &R, VPTypeAnalysis &TypeInfo) {
     return R.getVPSingleValue()->replaceAllUsesWith(R.getOperand(1));
 }
 
-/// Try to simplify the recipes in \p Plan
-static void simplifyRecipes(VPlan &Plan) {
+/// Try to simplify the recipes in \p Plan. If \p CanonicalIVTy is not nullptr,
+/// use it directly instead of retrieving the canonical IV type from the plan
+/// which may not exist any longer.
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ayalz wrote:

Simpler to always pass in this Type, which is essentially the type of all "symbolic live-ins" - those whose underlying IR value will be generated later / at code-gen. Or find a way for each such live-in to provide its type.

https://github.com/llvm/llvm-project/pull/108378