mirror of
https://github.com/torvalds/linux.git
synced 2024-11-18 01:51:53 +00:00
017f161a55
Enable the compiler intrinsic for byte swapping on arch ARM. This allows the compiler to detect and be able to optimize out byte swappings, and has a very modest benefit on vmlinux size (Linaro gcc 4.8): text data bss dec hex filename 2840310 123932 61960 3026202 2e2d1a vmlinux-lart #orig 2840152 123932 61960 3026044 2e2c7c vmlinux-lart #builtin-bswap 6473120 314840 5616016 12403976 bd4508 vmlinux-mxs #orig 6472586 314848 5616016 12403450 bd42fa vmlinux-mxs #builtin-bswap 7419872 318372 379556 8117800 7bde28 vmlinux-imx_v6_v7 #orig 7419170 318364 379556 8117090 7bdb62 vmlinux-imx_v6_v7 #builtin-bswap Signed-off-by: Kim Phillips <kim.phillips@freescale.com> Reviewed-by: Nicolas Pitre <nico@linaro.org> Acked-by: David Woodhouse <David.Woodhouse@intel.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
37 lines
591 B
ArmAsm
37 lines
591 B
ArmAsm
#include <linux/linkage.h>
|
|
|
|
#if __LINUX_ARM_ARCH__ >= 6
|
|
ENTRY(__bswapsi2)
|
|
rev r0, r0
|
|
bx lr
|
|
ENDPROC(__bswapsi2)
|
|
|
|
ENTRY(__bswapdi2)
|
|
rev r3, r0
|
|
rev r0, r1
|
|
mov r1, r3
|
|
bx lr
|
|
ENDPROC(__bswapdi2)
|
|
#else
|
|
ENTRY(__bswapsi2)
|
|
eor r3, r0, r0, ror #16
|
|
mov r3, r3, lsr #8
|
|
bic r3, r3, #0xff00
|
|
eor r0, r3, r0, ror #8
|
|
mov pc, lr
|
|
ENDPROC(__bswapsi2)
|
|
|
|
ENTRY(__bswapdi2)
|
|
mov ip, r1
|
|
eor r3, ip, ip, ror #16
|
|
eor r1, r0, r0, ror #16
|
|
mov r1, r1, lsr #8
|
|
mov r3, r3, lsr #8
|
|
bic r3, r3, #0xff00
|
|
bic r1, r1, #0xff00
|
|
eor r1, r1, r0, ror #8
|
|
eor r0, r3, ip, ror #8
|
|
mov pc, lr
|
|
ENDPROC(__bswapdi2)
|
|
#endif
|