[PATCH] D132634: [AArch64] Add index check before lowerInterleavedStore() uses ShuffleVectorInst's mask

[Peter Rong via Phabricator via llvm-commits]

Peter added inline comments.


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Comment at: llvm/test/CodeGen/AArch64/aarch64-shuffle-undef.ll:24
+  %B = urem <32 x i16> <i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1>, <i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1, i16 -1>
+  %S = shufflevector <32 x i16> %B, <32 x i16> %B, <32 x i32> undef
+  store <32 x i16> %S, <32 x i16>* %A2, align 64
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fhahn wrote:
> can the vectors be shortened here? Does it also crash with a `poison` mask?
>From my experience, it seems only lengths of 32 will trigger the bug.

I just tested again. `undef` crashes both Debug and Release build. `poison` only crashes Debug build. This just adds the mystery for me...

I checked the failed testcases in Transform, it seems they only considered when part of the Mask is undef or poison, not the whole Mask.


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  https://reviews.llvm.org/D132634/new/

https://reviews.llvm.org/D132634