https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70821
Jakub Jelinek <jakub at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|NEW |ASSIGNED
Assignee|unassigned at gcc dot gnu.org |jakub at gcc dot gnu.org
--- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Created attachment 38356
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=38356&action=edit
gcc7-pr70821.patch
For -Os, the problem is that peephole2 pass first replaces the movl $-1, %eax
instruction with orl $-1, %eax as the latter is 2 bytes shorter, and then the
peephole2 for the atomic decrement + comparison doesn't trigger anymore.
