I'm quite sure there are g965 boards around which indeed support Pentium 4 (and P4-based Celerons) (but yes I guess cmov and at least sse2 are safe - not that the p4 had a usable cmov implementation as it was incredibly slow IIRC but it should at least work).
Roland Am 25.01.2013 04:33, schrieb Eric Anholt: > While most of our development and testing is on x86-64, some of our > major consumers of the driver are on i386 still. This meant they aren't > taking advantage of SSE for floating point math or cmov instructions, > unless the user went out of their way to choose a -march flag > (unlikely). Given that the driver can only get probed on i965 and newer > chipsets, which only support core2 and above CPUs, this is safe. > > Improves (32-bit) GLbenchmark 2.1 offscreen performance by .76 +/- 0.35% > (n=19) > --- > configure.ac | 17 +++++++++++++++++ > src/mesa/drivers/dri/i965/Makefile.am | 3 ++- > 2 files changed, 19 insertions(+), 1 deletion(-) > > diff --git a/configure.ac b/configure.ac > index e769eda..0af3176 100644 > --- a/configure.ac > +++ b/configure.ac > @@ -492,6 +492,23 @@ if test "x$enable_asm" = xyes; then > fi > AC_SUBST([MESA_ASM_FILES]) > > +# If the user hasn't set an explicit -march flag, then autodetect a few for > +# use by the i965 driver. > +if echo $CFLAGS | grep -v march > /dev/null; then > + case "$host_cpu" in > + i?86 | x86_64) > + save_CFLAGS="$CFLAGS" > + AC_MSG_CHECKING([whether $CC supports -march=core2]) > + CFLAGS="$save_CFLAGS -march=core2" > + AC_COMPILE_IFELSE([AC_LANG_PROGRAM([], [[]])], > + [AC_MSG_RESULT([yes]); > MARCH_CORE2="-march=core2"], > + [AC_MSG_RESULT([no]); MARCH_CORE2=""]) > + CFLAGS="$save_CFLAGS" > + ;; > + esac > +fi > +AC_SUBST([MARCH_CORE2]) > + > dnl Check to see if dlopen is in default libraries (like Solaris, which > dnl has it in libc), or if libdl is needed to get it. > AC_CHECK_FUNC([dlopen], [DEFINES="$DEFINES -DHAVE_DLOPEN"], > diff --git a/src/mesa/drivers/dri/i965/Makefile.am > b/src/mesa/drivers/dri/i965/Makefile.am > index dc140df..d5d0631 100644 > --- a/src/mesa/drivers/dri/i965/Makefile.am > +++ b/src/mesa/drivers/dri/i965/Makefile.am > @@ -38,7 +38,8 @@ AM_CFLAGS = \ > $(DEFINES) \ > $(API_DEFINES) \ > $(VISIBILITY_CFLAGS) \ > - $(INTEL_CFLAGS) > + $(INTEL_CFLAGS) \ > + $(MARCH_CORE2) > > AM_CXXFLAGS = $(AM_CFLAGS) > > _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
