mirror of https://gitee.com/openkylin/linux.git
1ee3630a3e
ARCH_USE_BUILTIN_BSWAP will use __builtin_bswap16(), __builtin_bswap32() and __builtin_bswap64() where available. This allows better instruction scheduling. On pre-R2 processors it will result in 32 bit and 64 bit swapping being performed in a call to a __bswapsi2() rsp. __bswapdi2() functions, so we add these, too. For a 4.2 kernel with GCC 4.9 this yields the following kernel sizes: text data bss dec hex filename 3996071 155804 88992 4240867 40b5e3 vmlinux ip22 baseline 3985687 159900 88992 4234579 409d53 vmlinux ip22 + bswap patch 6913157 378552 251024 7542733 7317cd vmlinux ip27 baseline 6878581 378552 251024 7508157 7290bd vmlinux ip27 + bswap patch 5773777 268752 187424 6229953 5f0fc1 vmlinux malta baseline 5773401 268752 187424 6229577 5f0e49 vmlinux malta + bswap patch Presumably the code size improvments yield better cache hit rate thus better performance compensating for the extra function call but this will still need to be benchmarked. Signed-off-by: Ralf Baechle <ralf@linux-mips.org> |
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| .. | ||
| Makefile | ||
| ashldi3.c | ||
| ashrdi3.c | ||
| bitops.c | ||
| bswapdi.c | ||
| bswapsi.c | ||
| cmpdi2.c | ||
| csum_partial.S | ||
| delay.c | ||
| dump_tlb.c | ||
| iomap-pci.c | ||
| iomap.c | ||
| libgcc.h | ||
| lshrdi3.c | ||
| memcpy.S | ||
| memset.S | ||
| mips-atomic.c | ||
| r3k_dump_tlb.c | ||
| strlen_user.S | ||
| strncpy_user.S | ||
| strnlen_user.S | ||
| ucmpdi2.c | ||
| uncached.c | ||