| commit | 47a9eeb9ba72fd30766bdf4faa7d46b8ca33a7fd | |
| author | Adhemerval Zanella <adhemerval.zanella@linaro.org> | |
| Tue, 24 Oct 2023 11:37:15 +0000 (24 08:37 -0300) | ||
| committer | Adhemerval Zanella <adhemerval.zanella@linaro.org> | |
| Tue, 19 Dec 2023 18:12:38 +0000 (19 15:12 -0300) | ||
| tree | 4ca5baa3c7cee9c6e40b0bfc583d8c0d2e3ccbe4 | treesnapshot (tar.gz zip) |
| parent | ecb1e7220ddc7a4845bbd1b6fd7fcf17aba566bd | commitdiff |
i686: Do not raise exception traps on fesetexcept (BZ 30989)
According to ISO C23 (7.6.4.4), fesetexcept is supposed to set
floating-point exception flags without raising a trap (unlike
feraiseexcept, which is supposed to raise a trap if feenableexcept
was called with the appropriate argument).
The flags can be set in the 387 unit or in the SSE unit. To set
a flag, it is sufficient to do it in the SSE unit, because that is
guaranteed to not trap. However, on i386 CPUs that have only a
387 unit, set the flags in the 387, as long as this cannot trap.
Checked on i686-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
According to ISO C23 (7.6.4.4), fesetexcept is supposed to set
floating-point exception flags without raising a trap (unlike
feraiseexcept, which is supposed to raise a trap if feenableexcept
was called with the appropriate argument).
The flags can be set in the 387 unit or in the SSE unit. To set
a flag, it is sufficient to do it in the SSE unit, because that is
guaranteed to not trap. However, on i386 CPUs that have only a
387 unit, set the flags in the 387, as long as this cannot trap.
Checked on i686-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>