[thirdparty/glibc.git] / sysdeps / sparc / sparc64 / memmove.S

/* Copy memory to memory until the specified number of bytes
   has been copied.  Overlap is handled correctly.
   For SPARC V9.
   Copyright (C) 2017-2019 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, see
   <https://www.gnu.org/licenses/>.  */

#include <sysdep.h>

#ifndef XCC
# define XCC    xcc
	.register	%g2, #scratch
#endif

ENTRY(memmove)
	mov	%o0, %g2	/* Save pointer to destination  */
	cmp	%o1, %o0	/* if from address is >= to use forward copy  */
	bgeu,a	%XCC, 2f	/* else use backward if ...  */
	 cmp	%o2, 17		/* delay slot, for small counts copy bytes  */

	sub	%o0, %o1, %o4	/* get difference of two addresses  */
	cmp	%o2, %o4	/* compare size and difference of addresses  */
	bgu	%XCC, .Lovbc	/* if size is bigger, have to do overlapped copy  */
	 cmp	%o2, 17		/* delay slot, for small counts copy bytes  */
/*
 * normal, copy forwards
 */
2:	ble	%XCC, .Ldbytecp
	 andcc	%o1, 3, %o5	/* is src word aligned  */
	bz,pn	%icc, .Laldst
	 cmp	%o5, 2		/* is src half-word aligned  */
	be,pn	%icc, .Ls2alg
	 cmp	%o5, 3		/* src is byte aligned  */
	ldub	[%o1], %o3	/* move 1 or 3 bytes to align it  */
	inc	1, %o1
	stb	%o3, [%o0]	/* move a byte to align src  */
	inc	1, %o0
	bne,pn	%icc, .Ls2alg
	 dec	%o2
	b	.Lald		/* now go align dest  */
	 andcc	%o0, 3, %o5

.Ls2alg:
	lduh	[%o1], %o3	/* know src is 2 byte aligned  */
	inc	2, %o1
	srl	%o3, 8, %o4
	stb	%o4, [%o0]	/* have to do bytes,  */
	stb	%o3, [%o0 + 1]	/* don't know dst alingment  */
	inc	2, %o0
	dec	2, %o2

.Laldst:
	andcc	%o0, 3, %o5	/* align the destination address  */
.Lald:	bz,pn	%icc, .Lw4cp
	 cmp	%o5, 2
	bz,pn	%icc, .Lw2cp
	 cmp	%o5, 3
.Lw3cp:
	lduw	[%o1], %o4
	inc	4, %o1
	srl	%o4, 24, %o5
	stb	%o5, [%o0]
	bne,pt	%icc, .Lw1cp
	 inc	%o0
	dec	1, %o2
	andn	%o2, 3, %o3	/* i3 is aligned word count  */
	dec	4, %o3		/* avoid reading beyond tail of src  */
	sub	%o1, %o0, %o1	/* i1 gets the difference  */

1:	sll	%o4, 8, %g1	/* save residual bytes  */
	lduw	[%o1+%o0], %o4
	deccc	4, %o3
	srl	%o4, 24, %o5	/* merge with residual  */
	or	%o5, %g1, %g1
	st	%g1, [%o0]
	bnz,pt	%XCC, 1b
	 inc	4, %o0
	sub	%o1, 3, %o1	/* used one byte of last word read  */
	and	%o2, 3, %o2
	b	7f
	 inc	4, %o2

.Lw1cp:
	srl	%o4, 8, %o5
	sth	%o5, [%o0]
	inc	2, %o0
	dec	3, %o2
	andn	%o2, 3, %o3
	dec	4, %o3		/* avoid reading beyond tail of src  */
	sub	%o1, %o0, %o1	/* i1 gets the difference  */

2:	sll	%o4, 24, %g1	/* save residual bytes  */
	lduw	[%o1+%o0], %o4
	deccc	4, %o3
	srl	%o4, 8, %o5	/* merge with residual  */
	or	%o5, %g1, %g1
	st	%g1, [%o0]
	bnz,pt	%XCC, 2b
	 inc	4, %o0
	sub	%o1, 1, %o1	/* used three bytes of last word read  */
	and	%o2, 3, %o2
	b	7f
	inc	4, %o2

.Lw2cp:
	lduw	[%o1], %o4
	inc	4, %o1
	srl	%o4, 16, %o5
	sth	%o5, [%o0]
	inc	2, %o0
	dec	2, %o2
	andn	%o2, 3, %o3	/* i3 is aligned word count  */
	dec	4, %o3		/* avoid reading beyond tail of src  */
	sub	%o1, %o0, %o1	/* i1 gets the difference  */

3:	sll	%o4, 16, %g1	/* save residual bytes  */
	lduw	[%o1+%o0], %o4
	deccc	4, %o3
	srl	%o4, 16, %o5	/* merge with residual  */
	or	%o5, %g1, %g1
	st	%g1, [%o0]
	bnz,pt	%XCC, 3b
	 inc	4, %o0
	sub	%o1, 2, %o1	/* used two bytes of last word read  */
	and	%o2, 3, %o2
	b	7f
	 inc	4, %o2

.Lw4cp:
	andn	%o2, 3, %o3	/* i3 is aligned word count  */
	sub	%o1, %o0, %o1	/* i1 gets the difference  */

1:	lduw	[%o1+%o0], %o4	/* read from address  */
	deccc	4, %o3		/* decrement count  */
	st	%o4, [%o0]	/* write at destination address  */
	bg,pt	%XCC, 1b
	 inc	4, %o0		/* increment to address  */
	b	7f
	 and	%o2, 3, %o2	/* number of leftover bytes, if any  */

/*
 * differenced byte copy, works with any alignment
 */
.Ldbytecp:
	b	7f
	 sub	%o1, %o0, %o1	/* i1 gets the difference  */

4:	stb	%o4, [%o0]	/* write to address  */
	inc	%o0		/* inc to address  */
7:	deccc	%o2		/* decrement count  */
	bge,a	%XCC, 4b	/* loop till done  */
	 ldub	[%o1+%o0], %o4	/* read from address  */
	retl
	 mov	%g2, %o0	/* return pointer to destination  */

/*
 * an overlapped copy that must be done "backwards"
 */
.Lovbc:
	add	%o1, %o2, %o1	/* get to end of source space  */
	add	%o0, %o2, %o0	/* get to end of destination space  */
	sub	%o1, %o0, %o1	/* i1 gets the difference  */

5:	dec	%o0		/* decrement to address  */
	ldub	[%o1+%o0], %o3	/* read a byte  */
	deccc	%o2		/* decrement count  */
	bg,pt	%XCC, 5b 	/* loop until done  */
	 stb	%o3, [%o0]	/* write byte  */
	retl
	 mov	%g2, %o0	/* return pointer to destination  */
END(memmove)

libc_hidden_builtin_def (memmove)
Commit	Line	Data
767a26d6 JM	1	/* Copy memory to memory until the specified number of bytes
	2	has been copied. Overlap is handled correctly.
	3	For SPARC V9.
04277e02	4	Copyright (C) 2017-2019 Free Software Foundation, Inc.
767a26d6 JM	5	This file is part of the GNU C Library.
	6
	7	The GNU C Library is free software; you can redistribute it and/or
	8	modify it under the terms of the GNU Lesser General Public
	9	License as published by the Free Software Foundation; either
	10	version 2.1 of the License, or (at your option) any later version.
	11
	12	The GNU C Library is distributed in the hope that it will be useful,
	13	but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	15	Lesser General Public License for more details.
	16
	17	You should have received a copy of the GNU Lesser General Public
	18	License along with the GNU C Library; if not, see
5a82c748	19	<https://www.gnu.org/licenses/>. */
767a26d6 JM	20
	21	#include <sysdep.h>
	22
	23	#ifndef XCC
	24	# define XCC xcc
	25	.register %g2, #scratch
	26	#endif
	27
	28	ENTRY(memmove)
	29	mov %o0, %g2 /* Save pointer to destination */
	30	cmp %o1, %o0 /* if from address is >= to use forward copy */
	31	bgeu,a %XCC, 2f /* else use backward if ... */
	32	cmp %o2, 17 /* delay slot, for small counts copy bytes */
	33
	34	sub %o0, %o1, %o4 /* get difference of two addresses */
	35	cmp %o2, %o4 /* compare size and difference of addresses */
	36	bgu %XCC, .Lovbc /* if size is bigger, have to do overlapped copy */
	37	cmp %o2, 17 /* delay slot, for small counts copy bytes */
	38	/*
	39	* normal, copy forwards
	40	*/
	41	2: ble %XCC, .Ldbytecp
	42	andcc %o1, 3, %o5 /* is src word aligned */
	43	bz,pn %icc, .Laldst
	44	cmp %o5, 2 /* is src half-word aligned */
	45	be,pn %icc, .Ls2alg
	46	cmp %o5, 3 /* src is byte aligned */
	47	ldub [%o1], %o3 /* move 1 or 3 bytes to align it */
	48	inc 1, %o1
	49	stb %o3, [%o0] /* move a byte to align src */
	50	inc 1, %o0
	51	bne,pn %icc, .Ls2alg
	52	dec %o2
	53	b .Lald /* now go align dest */
	54	andcc %o0, 3, %o5
	55
	56	.Ls2alg:
	57	lduh [%o1], %o3 /* know src is 2 byte aligned */
	58	inc 2, %o1
	59	srl %o3, 8, %o4
	60	stb %o4, [%o0] /* have to do bytes, */
	61	stb %o3, [%o0 + 1] /* don't know dst alingment */
	62	inc 2, %o0
	63	dec 2, %o2
	64
	65	.Laldst:
	66	andcc %o0, 3, %o5 /* align the destination address */
	67	.Lald: bz,pn %icc, .Lw4cp
	68	cmp %o5, 2
	69	bz,pn %icc, .Lw2cp
	70	cmp %o5, 3
	71	.Lw3cp:
	72	lduw [%o1], %o4
	73	inc 4, %o1
	74	srl %o4, 24, %o5
	75	stb %o5, [%o0]
	76	bne,pt %icc, .Lw1cp
	77	inc %o0
	78	dec 1, %o2
	79	andn %o2, 3, %o3 /* i3 is aligned word count */
	80	dec 4, %o3 /* avoid reading beyond tail of src */
	81	sub %o1, %o0, %o1 /* i1 gets the difference */
	82
	83	1: sll %o4, 8, %g1 /* save residual bytes */
84	lduw [%o1+%o0], %o4
85	deccc 4, %o3
86	srl %o4, 24, %o5 /* merge with residual */
87	or %o5, %g1, %g1
88	st %g1, [%o0]
89	bnz,pt %XCC, 1b
90	inc 4, %o0
91	sub %o1, 3, %o1 /* used one byte of last word read */
92	and %o2, 3, %o2
93	b 7f
94	inc 4, %o2
95
96	.Lw1cp:
97	srl %o4, 8, %o5
98	sth %o5, [%o0]
99	inc 2, %o0
100	dec 3, %o2
101	andn %o2, 3, %o3
102	dec 4, %o3 /* avoid reading beyond tail of src */
103	sub %o1, %o0, %o1 /* i1 gets the difference */
104
105	2: sll %o4, 24, %g1 /* save residual bytes */
106	lduw [%o1+%o0], %o4
107	deccc 4, %o3
108	srl %o4, 8, %o5 /* merge with residual */
109	or %o5, %g1, %g1
110	st %g1, [%o0]
111	bnz,pt %XCC, 2b
112	inc 4, %o0
113	sub %o1, 1, %o1 /* used three bytes of last word read */
114	and %o2, 3, %o2
115	b 7f
116	inc 4, %o2
117
118	.Lw2cp:
119	lduw [%o1], %o4
120	inc 4, %o1
121	srl %o4, 16, %o5
122	sth %o5, [%o0]
123	inc 2, %o0
124	dec 2, %o2
125	andn %o2, 3, %o3 /* i3 is aligned word count */
126	dec 4, %o3 /* avoid reading beyond tail of src */
127	sub %o1, %o0, %o1 /* i1 gets the difference */
128
129	3: sll %o4, 16, %g1 /* save residual bytes */
130	lduw [%o1+%o0], %o4
131	deccc 4, %o3
132	srl %o4, 16, %o5 /* merge with residual */
133	or %o5, %g1, %g1
134	st %g1, [%o0]
135	bnz,pt %XCC, 3b
136	inc 4, %o0
137	sub %o1, 2, %o1 /* used two bytes of last word read */
138	and %o2, 3, %o2
139	b 7f
140	inc 4, %o2
141
142	.Lw4cp:
143	andn %o2, 3, %o3 /* i3 is aligned word count */
144	sub %o1, %o0, %o1 /* i1 gets the difference */
145
146	1: lduw [%o1+%o0], %o4 /* read from address */
147	deccc 4, %o3 /* decrement count */
148	st %o4, [%o0] /* write at destination address */
149	bg,pt %XCC, 1b
150	inc 4, %o0 /* increment to address */
151	b 7f
152	and %o2, 3, %o2 /* number of leftover bytes, if any */
153
154	/*
155	* differenced byte copy, works with any alignment
156	*/
157	.Ldbytecp:
158	b 7f
159	sub %o1, %o0, %o1 /* i1 gets the difference */
160
161	4: stb %o4, [%o0] /* write to address */
162	inc %o0 /* inc to address */
163	7: deccc %o2 /* decrement count */
164	bge,a %XCC, 4b /* loop till done */
165	ldub [%o1+%o0], %o4 /* read from address */
166	retl
167	mov %g2, %o0 /* return pointer to destination */
168
169	/*
170	* an overlapped copy that must be done "backwards"
171	*/
172	.Lovbc:
173	add %o1, %o2, %o1 /* get to end of source space */
174	add %o0, %o2, %o0 /* get to end of destination space */
175	sub %o1, %o0, %o1 /* i1 gets the difference */
176
177	5: dec %o0 /* decrement to address */
178	ldub [%o1+%o0], %o3 /* read a byte */
179	deccc %o2 /* decrement count */
180	bg,pt %XCC, 5b /* loop until done */
181	stb %o3, [%o0] /* write byte */
182	retl
183	mov %g2, %o0 /* return pointer to destination */
184	END(memmove)
185
186	libc_hidden_builtin_def (memmove)