renegade-project/linux-next
2
0
Fork 0
mirror of https://github.com/edk2-porting/linux-next.git synced 2024-11-19 16:14:13 +08:00
Code

[ARM] 3239/1: Add ARM optimised swab32

Browse Source 
Patch from Andre McCurdy

Replaces generic swab32 routine with a more ARM friendly version.
Reduces kernel text size by approx 1200 bytes when compiled with
3.4.4 and approx 2400 bytes with 4.0.2

Probably some performance benefit as well.

Signed-off-by: Andre McCurdy <armccurdy@yahoo.co.uk>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This commit is contained in:
Andre McCurdy 2006-01-07 11:39:20 +00:00 committed by Russell King
parent 2c041f4b9b
commit 6351610d69
1 changed files with 14 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

15
include/asm-arm/byteorder.h
View File

@ -15,9 +15,22 @@
#ifndef __ASM_ARM_BYTEORDER_H
#define __ASM_ARM_BYTEORDER_H
#include <asm/types.h>
static inline __attribute_const__ __u32 ___arch__swab32(__u32 x)
{
__u32 t;
t = x ^ ((x << 16) | (x >> 16)); /* eor r1,r0,r0,ror #16 */
x = (x << 24) | (x >> 8); /* mov r0,r0,ror #8 */
t &= ~0x00FF0000; /* bic r1,r1,#0x00FF0000 */
x ^= (t >> 8); /* eor r0,r0,r1,lsr #8 */
return x;
}
#define __arch__swab32(x) ___arch__swab32(x)
#if !defined(__STRICT_ANSI__) || defined(__KERNEL__)
# define __BYTEORDER_HAS_U64__
# define __SWAB_64_THRU_32__