[llvm] [LV] Convert gather loads with constant stride into strided loads (PR #147297)

[Mel Chen via llvm-commits]

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@@ -7904,16 +7908,21 @@ VPlanPtr LoopVectorizationPlanner::tryToBuildVPlanWithVPRecipes(
                    Range);
   }
 
-  for (ElementCount VF : Range)
-    Plan->addVF(VF);
-  Plan->setName("Initial VPlan");
-
   // Interleave memory: for each Interleave Group we marked earlier as relevant
   // for this VPlan, replace the Recipes widening its memory instructions with a
   // single VPInterleaveRecipe at its insertion point.
   RUN_VPLAN_PASS(VPlanTransforms::createInterleaveGroups, *Plan,
                  InterleaveGroups, RecipeBuilder, CM.isEpilogueAllowed());
 
+  // Convert memory recipes to strided access recipes if the strided access is
+  // legal and profitable.
+  RUN_VPLAN_PASS(VPlanTransforms::convertToStridedAccesses, *Plan, PSE,
+                 *OrigLoop, CostCtx, Range);
+
+  for (ElementCount VF : Range)
+    Plan->addVF(VF);
+  Plan->setName("Initial VPlan");
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Mel-Chen wrote:

This just moves VPlanTransforms::createInterleaveGroups forward.

https://github.com/llvm/llvm-project/pull/147297