[llvm] [LV] Bring isLegalGatherOrScatter in line with existing method (NFC) (PR #221698)

[David Sherwood via llvm-commits]

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@@ -147,19 +147,13 @@ bool VFSelectionContext::isLegalMaskedLoadOrStore(bool IsLoad, Type *ScalarTy,
                  : TTI.isLegalMaskedStore(ScalarTy, Alignment, AddressSpace));
 }
 
-bool VFSelectionContext::isLegalGatherOrScatter(Value *V,
+bool VFSelectionContext::isLegalGatherOrScatter(bool IsLoad, Type *ScalarTy,
+                                                Align Alignment,
                                                 ElementCount VF) const {
-  bool LI = isa<LoadInst>(V);
-  bool SI = isa<StoreInst>(V);
-  if (!LI && !SI)
-    return false;
-  auto *Ty = getLoadStoreType(V);
-  Align Align = getLoadStoreAlignment(V);
-  if (VF.isVector())
-    Ty = VectorType::get(Ty, VF);
+  Type *VectorTy = toVectorTy(ScalarTy, VF);
   return ForceTargetSupportsGatherScatterOps ||
-         (LI && TTI.isLegalMaskedGather(Ty, Align)) ||
-         (SI && TTI.isLegalMaskedScatter(Ty, Align));
+         (IsLoad ? TTI.isLegalMaskedGather(VectorTy, Alignment)
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david-arm wrote:

Perhaps because most targets have all vector variants of masked loads, whereas gathers are more complicated because they also take a vector of pointers. Some targets may not support <8 x i16> variants of gathers because that would require a <8 x ptr> type to also be legal.

https://github.com/llvm/llvm-project/pull/221698