From: David Woodhouse <David.Woodhouse@xxxxxxxxx> By using the compiler intrinsics instead of hand-crafted opaque inline assembler for byte-swapping, we let the compiler see what's actually happening and it gets to use lwbrx/stwbrx instructions instead of a normal load/store coupled with a sequence of rlwimi instructions to move bits around. Compiled-tested only. It gave a code size reduction of almost 4% for ext2, and more like 2.5% for ext3/ext4. Signed-off-by: David Woodhouse <David.Woodhouse@xxxxxxxxx> --- arch/powerpc/Kconfig | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index a902a5c..b4ea516 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -78,6 +78,9 @@ config ARCH_HAS_ILOG2_U64 bool default y if 64BIT +config ARCH_USE_BUILTIN_BSWAP + def_bool y + config GENERIC_HWEIGHT bool default y -- 1.8.0 -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
