[PATCH] D51240: Add a flag to remap manglings when reading profile data information.

Duncan P. N. Exon Smith via Phabricator via llvm-commits llvm-commits at lists.llvm.org
Mon Aug 27 10:19:03 PDT 2018


dexonsmith added a comment.

In https://reviews.llvm.org/D51240#1213358, @davidxl wrote:

> Re  "Why not":
>
> The common use model of instrumentation based PGO and SamplePGO are quite different. The former usually uses 'fresh' profile that matches the source. If there are massive code refactoring or ABI changes, the user can simply regenerate the profile.  For the latter, the profile data is usually collected from production binaries, so the source is almost always newer than the profile.


Frontend-based instrumentation is designed to degrade gracefully as the source changes.  I don't follow your conclusion that the profile is necessarily fresh.  (I'm fine with the patch being split though.)


https://reviews.llvm.org/D51240





More information about the llvm-commits mailing list