Commit Graph

2 Commits

Author SHA1 Message Date
Hongtao Yu bd52495518 [CSSPGO] Undoing the concept of dangling pseudo probe
As a follow-up to https://reviews.llvm.org/D104129, I'm cleaning up the danling probe related code in both the compiler and llvm-profgen.

I'm seeing a 5% size win for the pseudo_probe section for SPEC2017 and 10% for Ciner. Certain benchmark such as 602.gcc has a 20% size win. No obvious difference seen on build time for SPEC2017 and Cinder.

Reviewed By: wenlei

Differential Revision: https://reviews.llvm.org/D104477
2021-06-18 15:14:11 -07:00
Hongtao Yu 3b51b51877 [CSSPGO][llvm-profgen] Report samples for untrackable frames.
Fixing an issue where samples collected for an untrackable frame is not reported. An untrackable frame refers to a frame whose caller is untrackable due to missing debug info or pseudo probe. Though the frame is connected to its parent frame through the frame pointer chain at runtime, the compiler cannot build the connection without debug info or pseudo probe. In such case we just need to report the untrackable frame as the base frame and all of its child frames.

With more samples reported I'm seeing this improves the performance of an internal benchmark by 2.5%.

Reviewed By: wenlei, wlei

Differential Revision: https://reviews.llvm.org/D102961
2021-05-24 12:39:12 -07:00