[Bug middle-end/72795] Missed optimization of external-linkage variables in presence of barriers

2016-08-04 Thread rguenth at gcc dot gnu.org
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=72795 Richard Biener changed: What|Removed |Added Status|UNCONFIRMED |RESOLVED Resolution|---

[Bug middle-end/72795] Missed optimization of external-linkage variables in presence of barriers

2016-08-03 Thread peter at cordes dot ca
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=72795 --- Comment #3 from Peter Cordes --- Based on further discussion (http://chat.stackoverflow.com/rooms/119045/discussion-between-a3f-and-peter-cordes), the only bug (or feature?) here is that asm("":::"memory") doesn't count as a reference for

[Bug middle-end/72795] Missed optimization of external-linkage variables in presence of barriers

2016-08-03 Thread ahmad at a3f dot at
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=72795 --- Comment #2 from Ahmad Fatoum --- The write that can't be optimized away is the final assignment to x. The `movl$1, x(%rip)` prior to the barrier should've been optimized out, IMO.

[Bug middle-end/72795] Missed optimization of external-linkage variables in presence of barriers

2016-08-03 Thread peter at cordes dot ca
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=72795 Peter Cordes changed: What|Removed |Added CC||peter at cordes dot ca --- Comment #1