Mesa (master): scons: Use -fno-builtin-memcmp.

[Jose Fonseca]

Module: Mesa
Branch: master
Commit: 983fa4ad523535debf2e94cf6ac1fd4c5630c0d2
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=983fa4ad523535debf2e94cf6ac1fd4c5630c0d2

Author: José Fonseca <jfonseca at vmware.com>
Date:   Wed Oct 12 20:42:05 2011 +0100

scons: Use -fno-builtin-memcmp.

ipers framerate on llmvpipe improves 60%.

Issue spotted by Adam Jackson <ajax at redhat.com>.

http://lists.freedesktop.org/archives/mesa-dev/2011-June/009077.html

---

 scons/gallium.py |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/scons/gallium.py b/scons/gallium.py
index 1c9c0ea..c3350b3 100755
--- a/scons/gallium.py
+++ b/scons/gallium.py
@@ -361,6 +361,9 @@ def generate(env):
             ccflags += ['-O0']
         else:
             ccflags += ['-O3']
+        # gcc's builtin memcmp is slower than glibc's
+        # http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43052
+        ccflags += ['-fno-builtin-memcmp']
         # Work around aliasing bugs - developers should comment this out
         ccflags += ['-fno-strict-aliasing']
         ccflags += ['-g']