xref: /minix/common/lib/libc/arch/sh3/string/memset.S (revision ebfedea0)
1/*	$NetBSD: memset.S,v 1.2 2008/02/16 17:37:13 apb Exp $	*/
2
3/*-
4 * Copyright (c) 2002 SHIMIZU Ryo.  All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 * 3. The name of the author may not be used to endorse or promote products
15 *    derived from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29#include <machine/asm.h>
30
31#if defined(LIBC_SCCS) && !defined(lint)
32	RCSID("$NetBSD: memset.S,v 1.2 2008/02/16 17:37:13 apb Exp $")
33#endif
34
35#define	REG_PTR				r0
36#define	REG_TMP1			r1
37
38#ifdef BZERO
39# define	REG_C			r2
40# define	REG_DST			r4
41# define	REG_LEN			r5
42#else
43# define	REG_DST0		r3
44# define	REG_DST			r4
45# define	REG_C			r5
46# define	REG_LEN			r6
47#endif
48
49#ifdef BZERO
50ENTRY(bzero)
51#else
52ENTRY(memset)
53	mov	REG_DST,REG_DST0	/* for return value */
54#endif
55	/* small amount to fill ? */
56	mov	#28,REG_TMP1
57	cmp/hs	REG_TMP1,REG_LEN	/* if (len >= 28) goto large; */
58	bt/s	large
59	mov	#12,REG_TMP1		/* if (len >= 12) goto small; */
60	cmp/hs	REG_TMP1,REG_LEN
61	bt/s	small
62#ifdef BZERO
63	mov	#0,REG_C
64#endif
65	/* very little fill (0 ~ 11 bytes) */
66	tst	REG_LEN,REG_LEN
67	add	REG_DST,REG_LEN
68	bt/s	done
69	add	#1,REG_DST
70
71	/* unroll 4 loops */
72	cmp/eq	REG_DST,REG_LEN
731:	mov.b	REG_C,@-REG_LEN
74	bt/s	done
75	cmp/eq	REG_DST,REG_LEN
76	mov.b	REG_C,@-REG_LEN
77	bt/s	done
78	cmp/eq	REG_DST,REG_LEN
79	mov.b	REG_C,@-REG_LEN
80	bt/s	done
81	cmp/eq	REG_DST,REG_LEN
82	mov.b	REG_C,@-REG_LEN
83	bf/s	1b
84	cmp/eq	REG_DST,REG_LEN
85done:
86#ifdef BZERO
87	rts
88	nop
89#else
90	rts
91	mov	REG_DST0,r0
92#endif
93
94
95small:
96	mov	REG_DST,r0
97	tst	#1,r0
98	bt/s	small_aligned
99	mov	REG_DST,REG_TMP1
100	shll	REG_LEN
101	mova	1f,r0			/* 1f must be 4bytes aligned! */
102	add	#16,REG_TMP1		/* REG_TMP1 = dst+16; */
103	sub	REG_LEN,r0
104	jmp	@r0
105	mov	REG_C,r0
106
107	.align	2
108	mov.b	r0,@(15,REG_TMP1)
109	mov.b	r0,@(14,REG_TMP1)
110	mov.b	r0,@(13,REG_TMP1)
111	mov.b	r0,@(12,REG_TMP1)
112	mov.b	r0,@(11,REG_TMP1)
113	mov.b	r0,@(10,REG_TMP1)
114	mov.b	r0,@(9,REG_TMP1)
115	mov.b	r0,@(8,REG_TMP1)
116	mov.b	r0,@(7,REG_TMP1)
117	mov.b	r0,@(6,REG_TMP1)
118	mov.b	r0,@(5,REG_TMP1)
119	mov.b	r0,@(4,REG_TMP1)
120	mov.b	r0,@(3,REG_TMP1)
121	mov.b	r0,@(2,REG_TMP1)
122	mov.b	r0,@(1,REG_TMP1)
123	mov.b	r0,@REG_TMP1
124	mov.b	r0,@(15,REG_DST)
125	mov.b	r0,@(14,REG_DST)
126	mov.b	r0,@(13,REG_DST)
127	mov.b	r0,@(12,REG_DST)
128	mov.b	r0,@(11,REG_DST)
129	mov.b	r0,@(10,REG_DST)
130	mov.b	r0,@(9,REG_DST)
131	mov.b	r0,@(8,REG_DST)
132	mov.b	r0,@(7,REG_DST)
133	mov.b	r0,@(6,REG_DST)
134	mov.b	r0,@(5,REG_DST)
135	mov.b	r0,@(4,REG_DST)
136	mov.b	r0,@(3,REG_DST)
137	mov.b	r0,@(2,REG_DST)
138	mov.b	r0,@(1,REG_DST)
139#ifdef BZERO
140	rts
1411:	mov.b	r0,@REG_DST
142#else
143	mov.b	r0,@REG_DST
1441:	rts
145	mov	REG_DST0,r0
146#endif
147
148
149/* 2 bytes aligned small fill */
150small_aligned:
151#ifndef BZERO
152	extu.b	REG_C,REG_TMP1		/* REG_C = ??????xx, REG_TMP1 = ????00xx */
153	shll8	REG_C			/* REG_C = ????xx00, REG_TMP1 = ????00xx */
154	or	REG_TMP1,REG_C		/* REG_C = ????xxxx */
155#endif
156
157	mov	REG_LEN,r0
158	tst	#1,r0			/* len is aligned? */
159	bt/s	1f
160	add	#-1,r0
161	mov.b	REG_C,@(r0,REG_DST)	/* fill last a byte */
162	mov	r0,REG_LEN
1631:
164
165	mova	1f,r0			/* 1f must be 4bytes aligned! */
166	sub	REG_LEN,r0
167	jmp	@r0
168	mov	REG_C,r0
169
170	.align	2
171	mov.w	r0,@(30,REG_DST)
172	mov.w	r0,@(28,REG_DST)
173	mov.w	r0,@(26,REG_DST)
174	mov.w	r0,@(24,REG_DST)
175	mov.w	r0,@(22,REG_DST)
176	mov.w	r0,@(20,REG_DST)
177	mov.w	r0,@(18,REG_DST)
178	mov.w	r0,@(16,REG_DST)
179	mov.w	r0,@(14,REG_DST)
180	mov.w	r0,@(12,REG_DST)
181	mov.w	r0,@(10,REG_DST)
182	mov.w	r0,@(8,REG_DST)
183	mov.w	r0,@(6,REG_DST)
184	mov.w	r0,@(4,REG_DST)
185	mov.w	r0,@(2,REG_DST)
186#ifdef BZERO
187	rts
1881:	mov.w	r0,@REG_DST
189#else
190	mov.w	r0,@REG_DST
1911:	rts
192	mov	REG_DST0,r0
193#endif
194
195
196
197	.align	2
198large:
199#ifdef BZERO
200	mov	#0,REG_C
201#else
202	extu.b	REG_C,REG_TMP1		/* REG_C = ??????xx, REG_TMP1 = ????00xx */
203	shll8	REG_C			/* REG_C = ????xx00, REG_TMP1 = ????00xx */
204	or	REG_C,REG_TMP1		/* REG_C = ????xx00, REG_TMP1 = ????xxxx */
205	swap.w	REG_TMP1,REG_C		/* REG_C = xxxx????, REG_TMP1 = ????xxxx */
206	xtrct	REG_TMP1,REG_C		/* REG_C = xxxxxxxx */
207#endif
208
209	mov	#3,REG_TMP1
210	tst	REG_TMP1,REG_DST
211	mov	REG_DST,REG_PTR
212	bf/s	unaligned_dst
213	add	REG_LEN,REG_PTR		/* REG_PTR = dst + len; */
214	tst	REG_TMP1,REG_LEN
215	bf/s	unaligned_len
216
217aligned:
218	/* fill 32*n bytes */
219	mov	#32,REG_TMP1
220	cmp/hi	REG_LEN,REG_TMP1
221	bt	9f
222	.align	2
2231:	sub	REG_TMP1,REG_PTR
224	mov.l	REG_C,@REG_PTR
225	sub	REG_TMP1,REG_LEN
226	mov.l	REG_C,@(4,REG_PTR)
227	cmp/hi	REG_LEN,REG_TMP1
228	mov.l	REG_C,@(8,REG_PTR)
229	mov.l	REG_C,@(12,REG_PTR)
230	mov.l	REG_C,@(16,REG_PTR)
231	mov.l	REG_C,@(20,REG_PTR)
232	mov.l	REG_C,@(24,REG_PTR)
233	bf/s	1b
234	mov.l	REG_C,@(28,REG_PTR)
2359:
236
237	/* fill left 4*n bytes */
238	cmp/eq	REG_DST,REG_PTR
239	bt	9f
240	add	#4,REG_DST
241	cmp/eq	REG_DST,REG_PTR
2421:	mov.l	REG_C,@-REG_PTR
243	bt/s	9f
244	cmp/eq	REG_DST,REG_PTR
245	mov.l	REG_C,@-REG_PTR
246	bt/s	9f
247	cmp/eq	REG_DST,REG_PTR
248	mov.l	REG_C,@-REG_PTR
249	bt/s	9f
250	cmp/eq	REG_DST,REG_PTR
251	mov.l	REG_C,@-REG_PTR
252	bf/s	1b
253	cmp/eq	REG_DST,REG_PTR
2549:
255#ifdef BZERO
256	rts
257	nop
258#else
259	rts
260	mov	REG_DST0,r0
261#endif
262
263
264unaligned_dst:
265	mov	#1,REG_TMP1
266	tst	REG_TMP1,REG_DST	/* if (dst & 1) {               */
267	add	#1,REG_TMP1
268	bt/s	2f
269	tst	REG_TMP1,REG_DST
270	mov.b	REG_C,@REG_DST		/*   *dst++ = c;                */
271	add	#1,REG_DST
272	tst	REG_TMP1,REG_DST
2732:					/* }                            */
274					/* if (dst & 2) {               */
275	bt	4f
276	mov.w	REG_C,@REG_DST		/*   *(uint16_t*)dst++ = c;    */
277	add	#2,REG_DST
2784:					/* }                            */
279
280
281	tst	#3,REG_PTR		/* if (ptr & 3) {               */
282	bt/s	4f			/*                              */
283unaligned_len:
284	tst	#1,REG_PTR		/*   if (ptr & 1) {             */
285	bt/s	2f
286	tst	#2,REG_PTR
287	mov.b	REG_C,@-REG_PTR		/*     --ptr = c;               */
2882:					/*   }                          */
289					/*   if (ptr & 2) {             */
290	bt	4f
291	mov.w	REG_C,@-REG_PTR		/*     *--(uint16_t*)ptr = c;  */
2924:					/*   }                          */
293					/* }                            */
294
295	mov	REG_PTR,REG_LEN
296	bra	aligned
297	sub	REG_DST,REG_LEN
298
299