Am 01.07.2016 um 00:59 schrieb Matt Turner: > According to the referenced bug report, gcc-4.5 and newer do not inline > memcmp(). I see no difference in performance of ipers with llvmpipe on a > Sandybridge (which does not have "Enhanced REP MOVSB/STOSB") by removing > this flag. > > I attempted to confirm the problem with gcc-4.4, but it fails to compile > for quite a few different reasons. > --- > configure.ac | 8 -------- > 1 file changed, 8 deletions(-) > > diff --git a/configure.ac b/configure.ac > index bd8842d..95cfc36 100644 > --- a/configure.ac > +++ b/configure.ac > @@ -304,10 +304,6 @@ if test "x$GCC" = xyes; then > # We don't want floating-point math functions to set errno or trap > CFLAGS="$CFLAGS -fno-math-errno -fno-trapping-math" > > - # gcc's builtin memcmp is slower than glibc's > - # http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43052 > - CFLAGS="$CFLAGS -fno-builtin-memcmp" > - > # Flags to help ensure that certain portions of the code -- and only > those > # portions -- can be built with MSVC: > # - src/util, src/gallium/auxiliary, rc/gallium/drivers/llvmpipe, and > @@ -343,10 +339,6 @@ if test "x$GXX" = xyes; then > > # Restore CXXFLAGS; VISIBILITY_CXXFLAGS are added to it where needed. > CXXFLAGS=$save_CXXFLAGS > - > - # gcc's builtin memcmp is slower than glibc's > - # http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43052 > - CXXFLAGS="$CXXFLAGS -fno-builtin-memcmp" > fi > > AC_SUBST([MSVC2013_COMPAT_CFLAGS]) >
FWIW we're using gcc 4.4.3... Technically the configure script only requires gcc 4.2 (albeit some parts have higher requirements) so if it doesn't compile that's a bug. But we're using scons to build so this should be ok (albeit I think different flags in configure.ac and scons are generally not a really good idea). Roland _______________________________________________ mesa-dev mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/mesa-dev
