[Bug middle-end/111523] Unexpected performance regression with -ftrivial-auto-var-init=zero for e.g. systemctl unmask

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111523 --- Comment #10 from qinzhao at gcc dot gnu.org --- (In reply to Andrew Pinski from comment #9) > Anways systemd has now changed the buffer to 256 which is much much smaller > and for most calls enough in size before needing to reallocate the

[Bug middle-end/111523] Unexpected performance regression with -ftrivial-auto-var-init=zero for e.g. systemctl unmask

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111523 Andrew Pinski changed: What|Removed |Added Status|UNCONFIRMED |RESOLVED Resolution|---

[Bug middle-end/111523] Unexpected performance regression with -ftrivial-auto-var-init=zero for e.g. systemctl unmask

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111523 --- Comment #8 from Andrew Pinski --- I also looked into extracting greedy_realloc into its own file and I don't see anything which would cause -ftrivial-auto-var-init=zero any difference.

[Bug middle-end/111523] Unexpected performance regression with -ftrivial-auto-var-init=zero for e.g. systemctl unmask

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111523 --- Comment #7 from Andrew Pinski --- One thing I noticed is that malloc_usable_size is used for greedy_realloc but that should not change based on if -ftrivial-auto-var-init is used or not.

[Bug middle-end/111523] Unexpected performance regression with -ftrivial-auto-var-init=zero for e.g. systemctl unmask

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111523 --- Comment #6 from Andrew Pinski --- (In reply to Sam James from comment #3) > manager_deserialize takes ~1s instead of ~0.2s I looked into manager-serialize.c and its code generation with and without -ftrivial-auto-var-init=zero and

[Bug middle-end/111523] Unexpected performance regression with -ftrivial-auto-var-init=zero for e.g. systemctl unmask

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111523 --- Comment #5 from Andrew Pinski --- Hmm, systemd uses the cleanup attribute ...

[Bug middle-end/111523] Unexpected performance regression with -ftrivial-auto-var-init=zero for e.g. systemctl unmask

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111523 --- Comment #4 from Andrew Pinski --- >From that github issue: Internal memory management to take exponentially longer on at least ARM platforms. This narrows things down slightly. But it also makes me think there is some brokenness inside

[Bug middle-end/111523] Unexpected performance regression with -ftrivial-auto-var-init=zero for e.g. systemctl unmask

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111523 --- Comment #3 from Sam James --- There's some trace output at https://github.com/systemd/systemd/issues/26950#issue-1637752077 but it's not quite the same as perf output. But they do identify some bad functions: """ Observations:

[Bug middle-end/111523] Unexpected performance regression with -ftrivial-auto-var-init=zero for e.g. systemctl unmask

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111523 qinzhao at gcc dot gnu.org changed: What|Removed |Added CC||qinzhao at gcc dot gnu.org

[Bug middle-end/111523] Unexpected performance regression with -ftrivial-auto-var-init=zero for e.g. systemctl unmask

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111523 Sam James changed: What|Removed |Added CC||siddhesh at gcc dot gnu.org --- Comment #1