Bug 2156679

Summary:	Build Clang with PGO
Product:	[Fedora] Fedora	Reporter:	Alexander Zaitsev <zamazan4ik>
Component:	clang	Assignee:	Tom Stellard <tstellar>
Status:	NEW ---	QA Contact:	Fedora Extras Quality Assurance <extras-qa>
Severity:	unspecified	Docs Contact:
Priority:	unspecified
Version:	38	CC:	airlied, jchecahi, kkleine, npopov, sbergman, serge.guelton, siddharth.kde, tstellar, tuliom
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Description Alexander Zaitsev 2022-12-28 06:22:01 UTC

Description of problem:

Clang supports (https://llvm.org/docs/HowToBuildWithPGO.html) bootstrapping with PGO. It increases Clang performance. The same thing is already enabled for GCC in Fedora (profiledbootstrap option). I think the same thing could be done for Clang since in the current build script I don't see that Clang is built with PGO.


Expected results:
Provided Clang binaries with Fedora are built with PGO.

Additional option:
Also you could try to build binary with LLVM BOLT (https://github.com/facebookincubator/BOLT/blob/main/bolt/docs/OptimizingClang.md) but I guess it's another question and it's much more complicated topic.

Comment 1 Ben Cotton 2023-02-07 15:04:14 UTC

This bug appears to have been reported against 'rawhide' during the Fedora Linux 38 development cycle.
Changing version to 38.