[PATCH] D105065: RegAlloc: Fix "SubRange for this mask not found" unreachable in SplitKit

[Krzysztof Parzyszek via Phabricator via llvm-commits]

kparzysz added a comment.

Sorry, the emails that I'm getting from the @-mentions look exactly the same as any other email from phabricator to llvm-commits, and with hundreds of these per day I only look at a few...

The special handling of PHIs (with the exact mask) was added in D88020 <https://reviews.llvm.org/D88020>.  It used to be finding a match that covered the given mask, but that commit made it look for an exact cover.  It appears that it's essentially incompatible with the call to `refineSubRanges`.

Testcases for the more complex scenarios are accumulated as bug reproducers.  There is no comprehensive coverage of all possible situations, so only one test failing with the removal of some piece of code is still pretty good (better than nothing).


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D105065/new/

https://reviews.llvm.org/D105065