[VPlan] Move logic to create interleave groups to VPlanTransforms (NFC).

This is a step towards further breaking up the rather large
tryToBuildVPlanWithVPRecipes. It moves logic create interleave groups to
VPlanTransforms.cpp, where similar replacements for other recipes are
defined as well (e.g. EVL-based ones)

Author: fhahn

llvm/lib/Transforms/Vectorize/LoopVectorize.cpp

@@ -8988,35 +8988,8 @@ LoopVectorizationPlanner::tryToBuildVPlanWithVPRecipes(VFRange &Range) {
   // 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.
-  for (const auto *IG : InterleaveGroups) {
-    auto *Recipe =
-        cast<VPWidenMemoryRecipe>(RecipeBuilder.getRecipe(IG->getInsertPos()));
-    SmallVector<VPValue *, 4> StoredValues;
-    for (unsigned i = 0; i < IG->getFactor(); ++i)
-      if (auto *SI = dyn_cast_or_null<StoreInst>(IG->getMember(i))) {
-        auto *StoreR = cast<VPWidenStoreRecipe>(RecipeBuilder.getRecipe(SI));
-        StoredValues.push_back(StoreR->getStoredValue());
-      }
-
-    bool NeedsMaskForGaps =
-        IG->requiresScalarEpilogue() && !CM.isScalarEpilogueAllowed();
-    assert((!NeedsMaskForGaps || useMaskedInterleavedAccesses(CM.TTI)) &&
-           "masked interleaved groups are not allowed.");
-    auto *VPIG = new VPInterleaveRecipe(IG, Recipe->getAddr(), StoredValues,
-                                        Recipe->getMask(), NeedsMaskForGaps);
-    VPIG->insertBefore(Recipe);
-    unsigned J = 0;
-    for (unsigned i = 0; i < IG->getFactor(); ++i)
-      if (Instruction *Member = IG->getMember(i)) {
-        VPRecipeBase *MemberR = RecipeBuilder.getRecipe(Member);
-        if (!Member->getType()->isVoidTy()) {
-          VPValue *OriginalV = MemberR->getVPSingleValue();
-          OriginalV->replaceAllUsesWith(VPIG->getVPValue(J));
-          J++;
-        }
-        MemberR->eraseFromParent();
-      }
-  }
+  VPlanTransforms::createInterleaveGroups(InterleaveGroups, RecipeBuilder,
+                                          CM.isScalarEpilogueAllowed());
 
   for (ElementCount VF : Range)
     Plan->addVF(VF);

llvm/lib/Transforms/Vectorize/VPlanTransforms.cpp

@@ -1520,3 +1520,38 @@ void VPlanTransforms::dropPoisonGeneratingRecipes(
     }
   }
 }
+
+void VPlanTransforms::createInterleaveGroups(
+    const SmallPtrSetImpl<const InterleaveGroup<Instruction> *> &InterleaveGroups,
+    VPRecipeBuilder &RecipeBuilder, bool ScalarEpilogueAllowed) {
+  // 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.
+  for (const auto *IG : InterleaveGroups) {
+    auto *Recipe =
+        cast<VPWidenMemoryRecipe>(RecipeBuilder.getRecipe(IG->getInsertPos()));
+    SmallVector<VPValue *, 4> StoredValues;
+    for (unsigned i = 0; i < IG->getFactor(); ++i)
+      if (auto *SI = dyn_cast_or_null<StoreInst>(IG->getMember(i))) {
+        auto *StoreR = cast<VPWidenStoreRecipe>(RecipeBuilder.getRecipe(SI));
+        StoredValues.push_back(StoreR->getStoredValue());
+      }
+
+    bool NeedsMaskForGaps =
+        IG->requiresScalarEpilogue() && !ScalarEpilogueAllowed;
+    auto *VPIG = new VPInterleaveRecipe(IG, Recipe->getAddr(), StoredValues,
+                                        Recipe->getMask(), NeedsMaskForGaps);
+    VPIG->insertBefore(Recipe);
+    unsigned J = 0;
+    for (unsigned i = 0; i < IG->getFactor(); ++i)
+      if (Instruction *Member = IG->getMember(i)) {
+        VPRecipeBase *MemberR = RecipeBuilder.getRecipe(Member);
+        if (!Member->getType()->isVoidTy()) {
+          VPValue *OriginalV = MemberR->getVPSingleValue();
+          OriginalV->replaceAllUsesWith(VPIG->getVPValue(J));
+          J++;
+        }
+        MemberR->eraseFromParent();
+      }
+  }
+}

llvm/lib/Transforms/Vectorize/VPlanTransforms.h

@@ -25,6 +25,7 @@ class ScalarEvolution;
 class PredicatedScalarEvolution;
 class TargetLibraryInfo;
 class VPBuilder;
+class VPRecipeBuilder;
 
 struct VPlanTransforms {
   /// Replaces the VPInstructions in \p Plan with corresponding
@@ -106,6 +107,13 @@ struct VPlanTransforms {
   /// this transformation.
   /// \returns true if the transformation succeeds, or false if it doesn't.
   static bool tryAddExplicitVectorLength(VPlan &Plan);
+
+  // For each Interleave Group in \p InterleaveGroups replace the Recipes
+  // widening its memory instructions with a single VPInterleaveRecipe at its
+  // insertion point.
+  static void createInterleaveGroups(
+      const SmallPtrSetImpl<const InterleaveGroup<Instruction> *> &InterleaveGroups,
+      VPRecipeBuilder &RecipeBuilder, bool ScalarEpilogueAllowed);
 };
 
 } // namespace llvm