[PATCH] D90098: [BasicAA] Don't pass through AA metadata (NFCI)

Nikita Popov via Phabricator via llvm-commits llvm-commits at lists.llvm.org
Sat Oct 24 08:11:30 PDT 2020


nikic created this revision.
nikic added reviewers: asbirlea, fhahn, dmgreen, hfinkel.
Herald added subscribers: llvm-commits, kosarev, hiraditya.
Herald added a project: LLVM.
nikic requested review of this revision.

BasicAA itself doesn't make use of AA metadata, but passes it through to recursive queries and makes it part of the cache key. Aliasing decisions that are based on AA metadata (i.e. TBAA and ScopedAA) are based *only* on AA metadata, so checking them with different pointer values or sizes is not useful, the result will always be the same.

By itself, this change is a mild compile-time improvement (https://llvm-compile-time-tracker.com/compare.php?from=93127a4d7350261ed9ee2ccaa9c369eda2b60198&to=f4d0c5f01dc446f0c40e8dd81e6b9e9b02217c4d&stat=instructions). However, the actual goal here is to remove the AA metadata from the cache key and thus reduce it's size significantly (from 96 to 32 bytes), which will be the more impactful change. I plan to do that as a followup, but could also include it here.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D90098

Files:
  llvm/include/llvm/Analysis/BasicAliasAnalysis.h
  llvm/lib/Analysis/BasicAliasAnalysis.cpp

-------------- next part --------------
A non-text attachment was scrubbed...
Name: D90098.300486.patch
Type: text/x-patch
Size: 12228 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20201024/435b5bef/attachment.bin>


More information about the llvm-commits mailing list