Retro68/gcc/newlib/libc/machine/arc/strcmp-archs.S
2017-10-07 02:16:47 +02:00

110 lines
2.9 KiB
ArmAsm

/*
Copyright (c) 2015, Synopsys, Inc. All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
1) Redistributions of source code must retain the above copyright notice,
this list of conditions and the following disclaimer.
2) Redistributions in binary form must reproduce the above copyright notice,
this list of conditions and the following disclaimer in the documentation
and/or other materials provided with the distribution.
3) Neither the name of the Synopsys, Inc., nor the names of its contributors
may be used to endorse or promote products derived from this software
without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
POSSIBILITY OF SUCH DAMAGE.
*/
/* This implementation is optimized for performance. For code size a generic
implementation of this function from newlib/libc/string/strcmp.c will be
used. */
#if !defined (__OPTIMIZE_SIZE__) && !defined (PREFER_SIZE_OVER_SPEED)
#include "asm.h"
#ifdef __ARCHS__
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
ENDFUNC (strcmp)
#endif /* __ARCHS__ */
#endif /* !__OPTIMIZE_SIZE__ && !PREFER_SIZE_OVER_SPEED */