WSL2-Linux-Kernel/arch/arc/lib/strcmp-archs.S

79 строки
1.3 KiB
ArmAsm

/*
* Copyright (C) 2014-15 Synopsys, Inc. (www.synopsys.com)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/linkage.h>
ENTRY(strcmp)
or r2, r0, r1
bmsk_s r2, r2, 1
brne r2, 0, @.Lcharloop
;;; s1 and s2 are word aligned
ld.ab r2, [r0, 4]
mov_s r12, 0x01010101
ror r11, r12
.align 4
.LwordLoop:
ld.ab r3, [r1, 4]
;; Detect NULL char in str1
sub r4, r2, r12
ld.ab r5, [r0, 4]
bic r4, r4, r2
and r4, r4, r11
brne.d.nt r4, 0, .LfoundNULL
;; Check if the read locations are the same
cmp r2, r3
beq.d .LwordLoop
mov.eq r2, r5
;; A match is found, spot it out
#ifdef __LITTLE_ENDIAN__
swape r3, r3
mov_s r0, 1
swape r2, r2
#else
mov_s r0, 1
#endif
cmp_s r2, r3
j_s.d [blink]
bset.lo r0, r0, 31
.align 4
.LfoundNULL:
#ifdef __BIG_ENDIAN__
swape r4, r4
swape r2, r2
swape r3, r3
#endif
;; Find null byte
ffs r0, r4
bmsk r2, r2, r0
bmsk r3, r3, r0
swape r2, r2
swape r3, r3
;; make the return value
sub.f r0, r2, r3
mov.hi r0, 1
j_s.d [blink]
bset.lo r0, r0, 31
.align 4
.Lcharloop:
ldb.ab r2, [r0, 1]
ldb.ab r3, [r1, 1]
nop
breq r2, 0, .Lcmpend
breq r2, r3, .Lcharloop
.align 4
.Lcmpend:
j_s.d [blink]
sub r0, r2, r3
END(strcmp)