From f9646d138f568ced95b29c20efdf902063c7ea96 Mon Sep 17 00:00:00 2001 From: Adhemerval Zanella Date: Tue, 28 Sep 2021 17:53:28 +0000 Subject: arm: Enable USE_ATOMIC_COMPILER_BUILTINS (BZ #24774) As per other architectures. I have checked on a armv8 hardware with the following configurations: arm-linux-gnueabihf (gcc built with --with-float=hard --with-cpu=arm926ej-s) armv5-linux-gnueabihf (-march=armv5te -mfpu=vfpv3) armv7-linux-gnueabihf (-march=armv7-a -mfpu=vfpv3) armv7-thumb-linux-gnueabihf (-march=armv7-a -mfpu=vfpv3 -mthumb) armv7-neon-linux-gnueabihf (-march=armv7-a -mfpu=neon) armv7-neonhard-linux-gnueabihf (-march=armv7-a -mfpu=neon -mfloat-abi=hard) Without any regression. I haven't dig into the code, but since Linux atomic-machine.h handle pre-ARMv6 and ARMv6 I expect the compiler might have some small room to optimize. The code size also improves is most of the configurations: * master text data bss dec hex filename 1727801 9720 37928 1775449 1b1759 arm-linux-gnueabihf/libc.so 1691729 9720 37928 1739377 1a8a71 arm-linux-gnueabihf-armv7-disable-multi-arch/libc.so 1725509 9720 37928 1773157 1b0e65 armv5-linux-gnueabihf/libc.so 1700757 9720 37928 1748405 1aadb5 armv6-linux-gnueabihf/libc.so 1698973 9720 37928 1746621 1aa6bd armv6t2-linux-gnueabihf/libc.so 1695481 9752 37928 1743161 1a9939 armv7-linux-gnueabihf/libc.so 1692917 9744 37928 1740589 1a8f2d armv7-neonhard-linux-gnueabihf/libc.so 1692917 9744 37928 1740589 1a8f2d armv7-neon-linux-gnueabihf/libc.so 1225353 9752 37928 1273033 136cc9 armv7-thumb-linux-gnueabihf/libc.so * patched text data bss dec hex filename 1726805 9720 37928 1774453 1b1375 arm-linux-gnueabihf/libc.so 1689321 9720 37928 1736969 1a8109 arm-linux-gnueabihf-armv7-disable-multi-arch/libc.so 1724433 9720 37928 1772081 1b0a31 armv5-linux-gnueabihf/libc.so 1698301 9720 37928 1745949 1aa41d armv6-linux-gnueabihf/libc.so 1696525 9720 37928 1744173 1a9d2d armv6t2-linux-gnueabihf/libc.so 1693009 9752 37928 1740689 1a8f91 armv7-linux-gnueabihf/libc.so 1690493 9744 37928 1738165 1a85b5 armv7-neonhard-linux-gnueabihf/libc.so 1690493 9744 37928 1738165 1a85b5 armv7-neon-linux-gnueabihf/libc.so 1223837 9752 37928 1271517 1366dd armv7-thumb-linux-gnueabihf/libc.so The idea is eventually move all architectures to use compiler builtins. Reviewed-by: Aurelien Jarno Tested-by: Aurelien Jarno --- sysdeps/arm/atomic-machine.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/sysdeps/arm/atomic-machine.h b/sysdeps/arm/atomic-machine.h index 9524043797..e1f7731df0 100644 --- a/sysdeps/arm/atomic-machine.h +++ b/sysdeps/arm/atomic-machine.h @@ -17,7 +17,7 @@ . */ #define __HAVE_64B_ATOMICS 0 -#define USE_ATOMIC_COMPILER_BUILTINS 0 +#define USE_ATOMIC_COMPILER_BUILTINS 1 #define ATOMIC_EXCHANGE_USES_CAS 1 void __arm_link_error (void); -- cgit 1.4.1