Hi! On 1/21/22 15:00, John Paul Adrian Glaubitz wrote: > While playing around with the compiler options trying to find a solution, I > made an interesting > discovery which is that GCC support 64-bit compare and swap on SPARCv8plus > but not on 32-bit > SPARCv9: > > glaubitz@gcc202:~$ echo | gcc -mv8plus -E -dM -|grep -i SWAP > #define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_1 1 > #define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_2 1 > #define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_4 1 > #define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_8 1 > glaubitz@gcc202:~$ echo | gcc -mcpu=v9 -m32 -E -dM -|grep -i SWAP > #define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_1 1 > #define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_2 1 > #define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_4 1 > glaubitz@gcc202:~$
It gets even more confusing since on Solaris, gcc will actually support 64-bit atomic operations when setting -mcpu=v9: sysadmin@deimos:~$ echo | gcc -m32 -mcpu=v9 -E -dM -|grep -i SWAP #define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_1 1 #define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_2 1 #define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_4 1 #define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_8 1 sysadmin@deimos:~$ Does anyone know the reasoning behind this? Adrian PS: Please CC me, I'm not subscribed. -- .''`. John Paul Adrian Glaubitz : :' : Debian Developer - glaub...@debian.org `. `' Freie Universitaet Berlin - glaub...@physik.fu-berlin.de `- GPG: 62FF 8A75 84E0 2956 9546 0006 7426 3B37 F5B5 F913
