[PATCH] D129137: [NFC][LoopVectorize] Explicitly disable tail-folding on some SVE tests

Mon Jul 18 08:17:08 PDT 2022

david-arm added a comment.

Hi @sdesmalen, I've updated the patch to only include those tests that would fail when tail-folding is enabled by default for SVE. The tests changed in D129986 <https://reviews.llvm.org/D129986> now represent a subset of these. The reasons for the mismatch between D129137 <https://reviews.llvm.org/D129137> and D129986 <https://reviews.llvm.org/D129986> are as follows:

1. scalable-strict-fadd.ll. There is already a RUN line for tail-folding, which was added by https://reviews.llvm.org/D129550.
2. sve-epilog-vect-* - these fail when TF is enabled because we no longer create epilogues. However, it doesn't really make much sense to add new tail-folding RUN lines for these because then we won't perform epilogue vectorisation.
3. scalarize-store-with-predication.ll. This tests a case where VF=1,IC=2. When we enable tail-folding for these tests, forcing VF=1 and IC=2, we then crash. At the moment this is an artificial case because it wouldn't normally happen in practice since when tail-folding is enabled we don't bother interleaving. However, we should probably fix this at some point. :)

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D129137/new/

https://reviews.llvm.org/D129137