diff options
| author | Emil Velikov <[email protected]> | 2014-11-15 18:37:22 +0000 |
|---|---|---|
| committer | Emil Velikov <[email protected]> | 2014-11-15 20:34:34 +0000 |
| commit | 1a6ae840413d7fb6d2e83f6a83081d5246c7ac9e (patch) | |
| tree | e59c07994487d764e1b176060855e3508b182885 /configure.ac | |
| parent | 3bc42a09e2d13c42e15423a17b5c571049a11224 (diff) | |
configure.ac: roll up a program for the sse4.1 check
So when checking/building sse code we have three possibilities:
1 Old compiler, throws an error when using -msse*
2 New compiler, user disables sse* (-mno-sse*)
3 New compiler, user doesn't disable sse
The original code, added code for #1 but not #2. Later on we patched
around the lack of handling #2 by wrapping the code in __SSE4_1__.
Yet it lead to a missing/undefined symbol in case of #1 or #2, which
might cause an issue for #2 when using the i965 driver.
A bit later we "fixed" the undefined symbol by using #1, rather than
updating it to handle #2. With this commit we set things straight :)
To top it all up, conventions state that in case of conflicting
(-enable-foo -disable-foo) options, the latter one takes precedence.
Thus we need to make sure to prepend -msse4.1 to CFLAGS in our test.
v2: Clean the #includes. Suggested by Ilia, Matt & Siavash.
Cc: "10.3 10.4" <[email protected]>
Tested-by: David Heidelberg <[email protected]>
Tested-by: Siavash Eliasi <[email protected]>
Reviewed-by: Matt Turner <[email protected]>
Signed-off-by: Emil Velikov <[email protected]>
Diffstat (limited to 'configure.ac')
| -rw-r--r-- | configure.ac | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/configure.ac b/configure.ac index 91e111b8eae..8aa070d2125 100644 --- a/configure.ac +++ b/configure.ac @@ -252,7 +252,16 @@ AC_SUBST([VISIBILITY_CXXFLAGS]) dnl dnl Optional flags, check for compiler support dnl -AX_CHECK_COMPILE_FLAG([-msse4.1], [SSE41_SUPPORTED=1], [SSE41_SUPPORTED=0]) +save_CFLAGS="$CFLAGS" +CFLAGS="-msse4.1 $CFLAGS" +AC_COMPILE_IFELSE([AC_LANG_SOURCE([[ +#include <smmintrin.h> +int main () { + __m128i a = _mm_set1_epi32 (0), b = _mm_set1_epi32 (0), c; + c = _mm_max_epu32(a, b); + return 0; +}]])], SSE41_SUPPORTED=1) +CFLAGS="$save_CFLAGS" if test "x$SSE41_SUPPORTED" = x1; then DEFINES="$DEFINES -DUSE_SSE41" fi |