[llvm] [SLP][REVEC] Support more mask pattern usage in shufflevector. (PR #106212)

[Alexey Bataev via llvm-commits]

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@@ -318,12 +317,11 @@ static unsigned getShufflevectorNumGroups(ArrayRef<Value *> VL) {
           int Index;
           if (!SV->isExtractSubvectorMask(Index))
             return false;
-          for (int I : seq<int>(Index, Index + SV->getShuffleMask().size()))
-            ExtractionIndex.push_back(I);
+          UsedIndex.set(Index, Index + SV->getShuffleMask().size());
           return true;
         }))
       return 0;
-    if (!is_sorted(ExtractionIndex))
+    if (!UsedIndex.all())
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alexey-bataev wrote:

I mean, <0,1> extracted several time, while <2,3> is not extracted at all 

https://github.com/llvm/llvm-project/pull/106212