[llvm] [VPlan] Extract reverse operation for reverse accesses (PR #146525)

[Luke Lau via llvm-commits]

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@@ -2151,6 +2151,22 @@ void VPlanTransforms::addActiveLaneMask(
   HeaderMask->eraseFromParent();
 }
 
+/// If \p R is a VPInstruction::Reverse, return a VPWidenIntrinsicRecipe
+/// for the vp.reverse intrinsic using \p EVL. Returns nullptr otherwise.
+static VPWidenIntrinsicRecipe *
+getEVLReverse(VPRecipeBase &R, VPTypeAnalysis &TypeInfo, VPValue &EVL) {
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lukel97 wrote:

I think we want to reuse a TypeInfo as long as possible as it preserves the cache and prevents unnecessary traversal of the VPlan to find the scalar type

https://github.com/llvm/llvm-project/pull/146525