[llvm] [LV] Support tail-folded epilogue loops (PR #208764)

[Florian Hahn via llvm-commits]

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@@ -7489,6 +7792,28 @@ static SmallVector<Instruction *> preparePlanForEpilogueVectorLoop(
           continue;
         }
       }
+    } else if (isa<VPActiveLaneMaskPHIRecipe>(&R)) {
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fhahn wrote:

I think it would probably help to simplify the patch if we limit the initial commit to `DataAndControlFlow`. I think there is another crash  with RISCV: https://llvm.godbolt.org/z/6rsrrxen1

https://github.com/llvm/llvm-project/pull/208764