On Wed, Dec 9, 2015 at 8:30 PM, Matt Turner <matts...@gmail.com> wrote: > On Tue, Dec 8, 2015 at 9:37 PM, Jonathan Gray <j...@jsg.id.au> wrote: >> Change the __m128i variables to be volatile so gcc 4.9 won't optimise >> all of them out with -O1 or greater. The _mm_set1_epi32/pinsrd calls >> still get optimised out but now there is at least one SSE4.1 instruction >> generated via _mm_max_epu32/pmaxud. When all of the sse4.1 instructions >> got optimised out the configure test would incorrectly pass when the >> compiler supported the intrinsics and the assembler didn't support the >> instructions. >> >> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=91806 >> Signed-off-by: Jonathan Gray <j...@jsg.id.au> >> Cc: "11.0 11.1" <mesa-sta...@lists.freedesktop.org> >> --- >> configure.ac | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/configure.ac b/configure.ac >> index 260934d..1d82e47 100644 >> --- a/configure.ac >> +++ b/configure.ac >> @@ -384,7 +384,7 @@ CFLAGS="$SSE41_CFLAGS $CFLAGS" >> AC_COMPILE_IFELSE([AC_LANG_SOURCE([[ >> #include <smmintrin.h> >> int main () { >> - __m128i a = _mm_set1_epi32 (0), b = _mm_set1_epi32 (0), c; >> + volatile __m128i a = _mm_set1_epi32 (0), b = _mm_set1_epi32 (0), c; >> c = _mm_max_epu32(a, b); >> return 0; > > I would have extracted an int from the result of _mm_max_epu32 and > returned that instead of 0.
Instead of the volatile I assume ? > _______________________________________________ > mesa-stable mailing list > mesa-sta...@lists.freedesktop.org > http://lists.freedesktop.org/mailman/listinfo/mesa-stable _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
