[SLP][REVEC] Apply RunSLPReVectorization to the existing code.

Author: HanKuanChen

llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp

@@ -231,12 +231,17 @@ static const unsigned MaxPHINumOperands = 128;
 /// avoids spending time checking the cost model and realizing that they will
 /// be inevitably scalarized.
 static bool isValidElementType(Type *Ty) {
+  if (RunSLPReVectorization && isa<FixedVectorType>(Ty))
+    Ty = Ty->getScalarType();
   return VectorType::isValidElementType(Ty) && !Ty->isX86_FP80Ty() &&
          !Ty->isPPC_FP128Ty();
 }
 
 /// \returns the vector type of ScalarTy based on vectorization factor.
 static FixedVectorType *getWidenedType(Type *ScalarTy, unsigned VF) {
+  if (auto *VecTy = dyn_cast<FixedVectorType>(ScalarTy))
+    return FixedVectorType::get(VecTy->getElementType(),
+                                VF * VecTy->getNumElements());
   return FixedVectorType::get(ScalarTy, VF);
 }
 
@@ -6783,21 +6788,23 @@ void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
     return;
   }
 
-  // Don't handle vectors.
-  if (S.OpValue->getType()->isVectorTy() &&
-      !isa<InsertElementInst>(S.OpValue)) {
-    LLVM_DEBUG(dbgs() << "SLP: Gathering due to vector type.\n");
-    newTreeEntry(VL, std::nullopt /*not vectorized*/, S, UserTreeIdx);
-    return;
-  }
-
-  if (StoreInst *SI = dyn_cast<StoreInst>(S.OpValue))
-    if (SI->getValueOperand()->getType()->isVectorTy()) {
-      LLVM_DEBUG(dbgs() << "SLP: Gathering due to store vector type.\n");
+  if (!RunSLPReVectorization) {
+    // Don't handle vectors.
+    if (S.OpValue->getType()->isVectorTy() &&
+        !isa<InsertElementInst>(S.OpValue)) {
+      LLVM_DEBUG(dbgs() << "SLP: Gathering due to vector type.\n");
       newTreeEntry(VL, std::nullopt /*not vectorized*/, S, UserTreeIdx);
       return;
     }
 
+    if (StoreInst *SI = dyn_cast<StoreInst>(S.OpValue))
+      if (SI->getValueOperand()->getType()->isVectorTy()) {
+        LLVM_DEBUG(dbgs() << "SLP: Gathering due to store vector type.\n");
+        newTreeEntry(VL, std::nullopt /*not vectorized*/, S, UserTreeIdx);
+        return;
+      }
+  }
+
   // If all of the operands are identical or constant we have a simple solution.
   // If we deal with insert/extract instructions, they all must have constant
   // indices, otherwise we should gather them, not try to vectorize.