Mesa (master): util: Prefer atomic intrinsics to inline assembly.

[Matt Turner]

Module: Mesa
Branch: master
Commit: 024db256d446668e65d39ca988b00ba16e3a88bc
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=024db256d446668e65d39ca988b00ba16e3a88bc

Author: Matt Turner <mattst88 at gmail.com>
Date:   Fri Nov 21 14:29:41 2014 -0800

util: Prefer atomic intrinsics to inline assembly.

Cuts a little more than 1k of .text size from i915g.

This was previously done in commit 5f66b340 and subsequently reverted in
commit 3661f757 after bug 30514 was filed. I believe the cause of bug
30514 wasn't anything related to cross compiling, but rather that the
toolchain used defaulted to -march=i386, and i386 doesn't have the
CMPXCHG or XADD instructions used to implement the intrinsics.

So we reverted a patch that improved things so that we didn't break
compilation for a platform that never could have worked anyway.

---

 src/gallium/auxiliary/util/u_atomic.h |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/gallium/auxiliary/util/u_atomic.h b/src/gallium/auxiliary/util/u_atomic.h
index 9731aa0..2500bc7 100644
--- a/src/gallium/auxiliary/util/u_atomic.h
+++ b/src/gallium/auxiliary/util/u_atomic.h
@@ -24,12 +24,12 @@
 #define PIPE_ATOMIC_MSVC_INTRINSIC
 #elif (defined(PIPE_CC_MSVC) && defined(PIPE_ARCH_X86))
 #define PIPE_ATOMIC_ASM_MSVC_X86                
+#elif defined(PIPE_CC_GCC) && (PIPE_CC_GCC_VERSION >= 401)
+#define PIPE_ATOMIC_GCC_INTRINSIC
 #elif (defined(PIPE_CC_GCC) && defined(PIPE_ARCH_X86))
 #define PIPE_ATOMIC_ASM_GCC_X86
 #elif (defined(PIPE_CC_GCC) && defined(PIPE_ARCH_X86_64))
 #define PIPE_ATOMIC_ASM_GCC_X86_64
-#elif defined(PIPE_CC_GCC) && (PIPE_CC_GCC_VERSION >= 401)
-#define PIPE_ATOMIC_GCC_INTRINSIC
 #else
 #error "Unsupported platform"
 #endif