[Bug target/85683] [8 Regression] GCC 8 stopped using RMW (Read Modify Write) instructions on x86[_64]

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85683

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[8/9 Regression] GCC 8      |[8 Regression] GCC 8
                   |stopped using RMW (Read     |stopped using RMW (Read
                   |Modify Write) instructions  |Modify Write) instructions
                   |on x86[_64]                 |on x86[_64]

--- Comment #6 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Fixed for GCC9 so far, will backport to 8.2 after a while.