[llvm] [LV] Factor costInterleaveGatherScatter (NFC) (PR #215857)

[Luke Lau via llvm-commits]

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@@ -2369,6 +2433,13 @@ bool LoopVectorizationCostModel::isLegalMaskedLoadOrStore(
                                          getLoadStoreAddressSpace(I));
 }
 
+bool LoopVectorizationCostModel::isLegalGatherOrScatter(Instruction *I,
+                                                        ElementCount VF) const {
+  assert((isa<LoadInst, StoreInst>(I)));
+  return Config.isLegalGatherOrScatter(isa<LoadInst>(I), getLoadStoreType(I),
+                                       getLoadStoreAlignment(I), VF);
+}
+
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lukel97 wrote:

This plus the `VFSelectionContext::isLegalGatherOrScatter` change could probably be split off and landed on their own, seeing as it brings the gather/scatter interface in line with isLegalMaskedLoadOrStore

https://github.com/llvm/llvm-project/pull/215857