81 lines
1.5 KiB
ArmAsm
81 lines
1.5 KiB
ArmAsm
/* strlen.S: Sparc optimized strlen code
|
|
* Hand optimized from GNU libc's strlen
|
|
* Copyright (C) 1991,1996 Free Software Foundation
|
|
* Copyright (C) 1996,2008 David S. Miller (davem@davemloft.net)
|
|
* Copyright (C) 1996, 1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
|
|
*/
|
|
|
|
#include <linux/linkage.h>
|
|
#include <asm/asm.h>
|
|
|
|
#define LO_MAGIC 0x01010101
|
|
#define HI_MAGIC 0x80808080
|
|
|
|
.text
|
|
ENTRY(strlen)
|
|
mov %o0, %o1
|
|
andcc %o0, 3, %g0
|
|
BRANCH32(be, pt, 9f)
|
|
sethi %hi(HI_MAGIC), %o4
|
|
ldub [%o0], %o5
|
|
BRANCH_REG_ZERO(pn, %o5, 11f)
|
|
add %o0, 1, %o0
|
|
andcc %o0, 3, %g0
|
|
BRANCH32(be, pn, 4f)
|
|
or %o4, %lo(HI_MAGIC), %o3
|
|
ldub [%o0], %o5
|
|
BRANCH_REG_ZERO(pn, %o5, 12f)
|
|
add %o0, 1, %o0
|
|
andcc %o0, 3, %g0
|
|
BRANCH32(be, pt, 5f)
|
|
sethi %hi(LO_MAGIC), %o4
|
|
ldub [%o0], %o5
|
|
BRANCH_REG_ZERO(pn, %o5, 13f)
|
|
add %o0, 1, %o0
|
|
BRANCH32(ba, pt, 8f)
|
|
or %o4, %lo(LO_MAGIC), %o2
|
|
9:
|
|
or %o4, %lo(HI_MAGIC), %o3
|
|
4:
|
|
sethi %hi(LO_MAGIC), %o4
|
|
5:
|
|
or %o4, %lo(LO_MAGIC), %o2
|
|
8:
|
|
ld [%o0], %o5
|
|
2:
|
|
sub %o5, %o2, %o4
|
|
andcc %o4, %o3, %g0
|
|
BRANCH32(be, pt, 8b)
|
|
add %o0, 4, %o0
|
|
|
|
/* Check every byte. */
|
|
srl %o5, 24, %g7
|
|
andcc %g7, 0xff, %g0
|
|
BRANCH32(be, pn, 1f)
|
|
add %o0, -4, %o4
|
|
srl %o5, 16, %g7
|
|
andcc %g7, 0xff, %g0
|
|
BRANCH32(be, pn, 1f)
|
|
add %o4, 1, %o4
|
|
srl %o5, 8, %g7
|
|
andcc %g7, 0xff, %g0
|
|
BRANCH32(be, pn, 1f)
|
|
add %o4, 1, %o4
|
|
andcc %o5, 0xff, %g0
|
|
BRANCH32_ANNUL(bne, pt, 2b)
|
|
ld [%o0], %o5
|
|
add %o4, 1, %o4
|
|
1:
|
|
retl
|
|
sub %o4, %o1, %o0
|
|
11:
|
|
retl
|
|
mov 0, %o0
|
|
12:
|
|
retl
|
|
mov 1, %o0
|
|
13:
|
|
retl
|
|
mov 2, %o0
|
|
ENDPROC(strlen)
|