[newlib-cygwin.git] / newlib / libc / machine / arc / strcpy-bs.S

/*
   Copyright (c) 2015-2024, 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/strcpy.c will be
   used.  */
#if !defined (__OPTIMIZE_SIZE__) && !defined (PREFER_SIZE_OVER_SPEED) \
    && !defined (__ARC_RF16__)

#include "asm.h"

#if (defined (__ARC700__) || defined (__ARCEM__) || defined (__ARCHS__)) \
    && defined (__ARC_BARREL_SHIFTER__)

/* If dst and src are 4 byte aligned, copy 8 bytes at a time.
   If the src is 4, but not 8 byte aligned, we first read 4 bytes to get
   it 8 byte aligned.  Thus, we can do a little read-ahead, without
   dereferencing a cache line that we should not touch.
   Note that short and long instructions have been scheduled to avoid
   branch stalls.
   The beq_s to r3z could be made unaligned & long to avoid a stall
   there, but the it is not likely to be taken often, and it
   would also be likey to cost an unaligned mispredict at the next call.  */

ENTRY (strcpy)
	or	r2,r0,r1
	bmsk_s	r2,r2,1
	brne.d	r2,0,charloop
	mov_s	r10,r0
	ld_s	r3,[r1,0]
	mov	r8,0x01010101
	bbit0.d	r1,2,loop_start
	ror	r12,r8
	sub	r2,r3,r8
	bic_s	r2,r2,r3
	tst_s	r2,r12
	bne_l	r3z
	mov_s	r4,r3
	.balign 4
loop:
	ld.a	r3,[r1,4]
	st.ab	r4,[r10,4]
loop_start:
	ld.a	r4,[r1,4]
	sub	r2,r3,r8
	bic_s	r2,r2,r3
	tst_l	r2,r12
	bne_l	r3z
	st.ab	r3,[r10,4]
	sub	r2,r4,r8
	bic	r2,r2,r4
	tst_l	r2,r12
	beq_l	loop
	mov_s	r3,r4
#ifdef __LITTLE_ENDIAN__
r3z:	bmsk.f	r1,r3,7
	lsr_s	r3,r3,8
#else
r3z:	lsr.f	r1,r3,24
	asl_s	r3,r3,8
#endif
	bne.d	r3z
	stb.ab	r1,[r10,1]
	j_s	[blink]

	.balign	4
charloop:
	ldb.ab	r3,[r1,1]


	brne.d	r3,0,charloop
	stb.ab	r3,[r10,1]
	j	[blink]
ENDFUNC (strcpy)
#endif /* (__ARC700__ || __ARCEM__ || __ARCHS__) && __ARC_BARREL_SHIFTER__ */

#endif /* !__OPTIMIZE_SIZE__ && !PREFER_SIZE_OVER_SPEED */
Commit	Line	Data
c0a99f02	1	/*
d85bb55f	2	Copyright (c) 2015-2024, Synopsys, Inc. All rights reserved.
c0a99f02 AK	3
	4	Redistribution and use in source and binary forms, with or without
	5	modification, are permitted provided that the following conditions are met:
	6
	7	1) Redistributions of source code must retain the above copyright notice,
	8	this list of conditions and the following disclaimer.
	9
	10	2) Redistributions in binary form must reproduce the above copyright notice,
	11	this list of conditions and the following disclaimer in the documentation
	12	and/or other materials provided with the distribution.
	13
	14	3) Neither the name of the Synopsys, Inc., nor the names of its contributors
	15	may be used to endorse or promote products derived from this software
	16	without specific prior written permission.
	17
	18	THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
	19	AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	20	IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	21	ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
	22	LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
	23	CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
	24	SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
	25	INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
	26	CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
	27	ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
	28	POSSIBILITY OF SUCH DAMAGE.
	29	*/
	30
	31	/* This implementation is optimized for performance. For code size a generic
	32	implementation of this function from newlib/libc/string/strcpy.c will be
	33	used. */
d85bb55f CZ	34	#if !defined (__OPTIMIZE_SIZE__) && !defined (PREFER_SIZE_OVER_SPEED) \
d85bb55f CZ	35	&& !defined (__ARC_RF16__)
c0a99f02 AK	36
	37	#include "asm.h"
	38
06537f05 AK	39	#if (defined (__ARC700__) \|\| defined (__ARCEM__) \|\| defined (__ARCHS__)) \
06537f05 AK	40	&& defined (__ARC_BARREL_SHIFTER__)
c0a99f02 AK	41
	42	/* If dst and src are 4 byte aligned, copy 8 bytes at a time.
	43	If the src is 4, but not 8 byte aligned, we first read 4 bytes to get
	44	it 8 byte aligned. Thus, we can do a little read-ahead, without
	45	dereferencing a cache line that we should not touch.
	46	Note that short and long instructions have been scheduled to avoid
	47	branch stalls.
	48	The beq_s to r3z could be made unaligned & long to avoid a stall
	49	there, but the it is not likely to be taken often, and it
	50	would also be likey to cost an unaligned mispredict at the next call. */
	51
	52	ENTRY (strcpy)
	53	or r2,r0,r1
	54	bmsk_s r2,r2,1
	55	brne.d r2,0,charloop
	56	mov_s r10,r0
	57	ld_s r3,[r1,0]
	58	mov r8,0x01010101
	59	bbit0.d r1,2,loop_start
	60	ror r12,r8
	61	sub r2,r3,r8
	62	bic_s r2,r2,r3
	63	tst_s r2,r12
	64	bne_l r3z
	65	mov_s r4,r3
	66	.balign 4
	67	loop:
	68	ld.a r3,[r1,4]
	69	st.ab r4,[r10,4]
	70	loop_start:
	71	ld.a r4,[r1,4]
	72	sub r2,r3,r8
	73	bic_s r2,r2,r3
	74	tst_l r2,r12
	75	bne_l r3z
	76	st.ab r3,[r10,4]
	77	sub r2,r4,r8
	78	bic r2,r2,r4
	79	tst_l r2,r12
	80	beq_l loop
	81	mov_s r3,r4
	82	#ifdef __LITTLE_ENDIAN__
	83	r3z: bmsk.f r1,r3,7
	84	lsr_s r3,r3,8
	85	#else
	86	r3z: lsr.f r1,r3,24
	87	asl_s r3,r3,8
	88	#endif
	89	bne.d r3z
	90	stb.ab r1,[r10,1]
	91	j_s [blink]
	92
	93	.balign 4
	94	charloop:
	95	ldb.ab r3,[r1,1]
	96
	97
	98	brne.d r3,0,charloop
	99	stb.ab r3,[r10,1]
	100	j [blink]
	101	ENDFUNC (strcpy)
06537f05	102	#endif /* (__ARC700__ \|\| __ARCEM__ \|\| __ARCHS__) && __ARC_BARREL_SHIFTER__ */
c0a99f02 AK	103
c0a99f02 AK	104	#endif /* !__OPTIMIZE_SIZE__ && !PREFER_SIZE_OVER_SPEED */