about summary refs log tree commit diff
path: root/sysdeps/ia64/memccpy.S
blob: 16c7666e38d3926b2de0eb5ced0e42cb1af16429 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
/* Optimized version of the memccpy() function.
   This file is part of the GNU C Library.
   Copyright (C) 2000-2020 Free Software Foundation, Inc.
   Contributed by Dan Pop <Dan.Pop@cern.ch>.

   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/>.  */

/* Return: a pointer to the next byte after char in dest or NULL

   Inputs:
        in0:    dest
        in1:    src
        in2:    char
        in3:    byte count

   This implementation assumes little endian mode (UM.be = 0).

   This implementation assumes that it is safe to do read ahead
   in the src block, without getting beyond its limit.  */

#include <sysdep.h>
#undef ret

#define OP_T_THRES 	16
#define OPSIZ 		8

#define saved_pr	r17
#define saved_lc	r18
#define dest		r19
#define src		r20
#define len		r21
#define asrc		r22
#define tmp		r23
#define char		r24
#define charx8		r25
#define saved_ec	r26
#define sh2		r28
#define	sh1		r29
#define loopcnt		r30
#define	value		r31

#ifdef GAS_ALIGN_BREAKS_UNWIND_INFO
/* Manually force proper loop-alignment.  Note: be sure to
   double-check the code-layout after making any changes to
   this routine! */
# define ALIGN(n)	{ nop 0 }
#else
# define ALIGN(n)	.align n
#endif

ENTRY(memccpy)
	.prologue
	alloc 	r2 = ar.pfs, 4, 40 - 4, 0, 40

#include "softpipe.h"
	.rotr	r[MEMLAT + 7], tmp1[4], tmp2[4], val[4], tmp3[2], pos0[2]
	.rotp	p[MEMLAT + 6 + 1]

	mov	ret0 = r0		// return NULL if no match
	.save pr, saved_pr
	mov	saved_pr = pr		// save the predicate registers
	mov 	dest = in0		// dest
	.save ar.lc, saved_lc
        mov 	saved_lc = ar.lc	// save the loop counter
        mov 	saved_ec = ar.ec	// save the loop counter
	.body
	mov 	src = in1		// src
	extr.u	char = in2, 0, 8	// char
	mov	len = in3		// len
	sub	tmp = r0, in0		// tmp = -dest
	cmp.ne	p7, p0 = r0, r0		// clear p7
	;;
	and	loopcnt = 7, tmp	// loopcnt = -dest % 8
	cmp.ge	p6, p0 = OP_T_THRES, len	// is len <= OP_T_THRES
	mov	ar.ec = 0		// ec not guaranteed zero on entry
(p6)	br.cond.spnt	.cpyfew		// copy byte by byte
	;;
	cmp.eq	p6, p0 = loopcnt, r0
	mux1	charx8 = char, @brcst
(p6)	br.cond.sptk .dest_aligned
	sub	len = len, loopcnt	// len -= -dest % 8
	adds	loopcnt = -1, loopcnt	// --loopcnt
	;;
	mov	ar.lc = loopcnt
.l1:					// copy -dest % 8 bytes
	ld1	value = [src], 1	// value = *src++
	;;
	st1	[dest] = value, 1	// *dest++ = value
	cmp.eq	p6, p0 = value, char
(p6)	br.cond.spnt .foundit
	br.cloop.dptk .l1
.dest_aligned:
	and	sh1 = 7, src 		// sh1 = src % 8
	and	tmp = -8, len   	// tmp = len & -OPSIZ
	and	asrc = -8, src		// asrc = src & -OPSIZ  -- align src
	shr.u	loopcnt = len, 3	// loopcnt = len / 8
	and	len = 7, len ;;		// len = len % 8
	shl	sh1 = sh1, 3		// sh1 = 8 * (src % 8)
	adds	loopcnt = -1, loopcnt	// --loopcnt
	mov     pr.rot = 1 << 16 ;;	// set rotating predicates
	sub	sh2 = 64, sh1		// sh2 = 64 - sh1
	mov	ar.lc = loopcnt		// set LC
	cmp.eq  p6, p0 = sh1, r0 	// is the src aligned?
(p6)    br.cond.sptk .src_aligned ;;
	add	src = src, tmp		// src += len & -OPSIZ
	mov	ar.ec = MEMLAT + 6 + 1 	// six more passes needed
	ld8	r[1] = [asrc], 8 	// r[1] = w0
	cmp.ne	p6, p0 = r0, r0	;;	// clear p6
	ALIGN(32)
.l2:
(p[0])		ld8.s	r[0] = [asrc], 8		// r[0] = w1
(p[MEMLAT])	shr.u	tmp1[0] = r[1 + MEMLAT], sh1	// tmp1 = w0 >> sh1
(p[MEMLAT])	shl	tmp2[0] = r[0 + MEMLAT], sh2  	// tmp2 = w1 << sh2
(p[MEMLAT+4])	xor	tmp3[0] = val[1], charx8
(p[MEMLAT+5])	czx1.r	pos0[0] = tmp3[1]
(p[MEMLAT+6])	chk.s	r[6 + MEMLAT], .recovery1	// our data isn't
							// valid - rollback!
(p[MEMLAT+6])	cmp.ne	p6, p0 = 8, pos0[1]
(p6)		br.cond.spnt	.gotit
(p[MEMLAT+6])	st8	[dest] = val[3], 8		// store val to dest
(p[MEMLAT+3])	or	val[0] = tmp1[3], tmp2[3] 	// val = tmp1 | tmp2
		br.ctop.sptk    .l2
		br.cond.sptk .cpyfew

.src_aligned:
		cmp.ne  p6, p0 = r0, r0			// clear p6
		mov     ar.ec = MEMLAT + 2 + 1 ;;	// set EC
.l3:
(p[0])		ld8.s	r[0] = [src], 8
(p[MEMLAT])	xor	tmp3[0] = r[MEMLAT], charx8
(p[MEMLAT+1])	czx1.r	pos0[0] = tmp3[1]
(p[MEMLAT+2])	cmp.ne	p7, p0 = 8, pos0[1]
(p[MEMLAT+2])	chk.s	r[MEMLAT+2], .recovery2
(p7)		br.cond.spnt	.gotit
.back2:
(p[MEMLAT+2])	st8	[dest] = r[MEMLAT+2], 8
		br.ctop.dptk .l3
.cpyfew:
	cmp.eq	p6, p0 = len, r0	// is len == 0 ?
	adds	len = -1, len		// --len;
(p6)	br.cond.spnt	.restore_and_exit ;;
	mov	ar.lc = len
.l4:
	ld1	value = [src], 1
	;;
	st1	[dest] = value, 1
	cmp.eq	p6, p0 = value, char
(p6)	br.cond.spnt .foundit
	br.cloop.dptk	.l4 ;;
.foundit:
(p6)	mov	ret0 = dest
.restore_and_exit:
	mov     pr = saved_pr, -1    	// restore the predicate registers
	mov 	ar.lc = saved_lc	// restore the loop counter
	mov 	ar.ec = saved_ec ;;	// restore the epilog counter
	br.ret.sptk.many b0
.gotit:
	.pred.rel "mutex" p6, p7
(p6)	mov	value = val[3]		// if coming from l2
(p7)	mov	value = r[MEMLAT+2]	// if coming from l3
	mov	ar.lc = pos0[1] ;;
.l5:
	extr.u	tmp = value, 0, 8 ;;
	st1	[dest] = tmp, 1
	shr.u	value = value, 8
	br.cloop.sptk .l5 ;;
	mov 	ret0 = dest
	mov	pr = saved_pr, -1
	mov	ar.lc = saved_lc
	br.ret.sptk.many b0

.recovery1:
#if MEMLAT != 6
# error "MEMLAT must be 6!"
#endif
	adds	src = -8, asrc
	mov	loopcnt = ar.lc
	mov	tmp = ar.ec
	;;
(p[0])	adds	src = -8, src
	;;
(p[1])	adds	src = -8, src
	sub	sh1 = (MEMLAT + 6 + 1), tmp
	;;
(p[2])	adds	src = -8, src
	;;
(p[3])	adds	src = -8, src
	shl	loopcnt = loopcnt, 3
	;;
(p[4])	adds	src = -8, src
	;;
(p[5])	adds	src = -8, src
	shl	sh1 = sh1, 3
	;;
(p[6])	adds	src = -8, src
	;;
(p[7])	adds	src = -8, src
	shl	tmp = tmp, 3
	;;
(p[8])	adds	src = -8, src
	;;
(p[9])	adds	src = -8, src
	shr.u	sh2 = sh2, 3
	;;
(p[10])	adds	src = -8, src
	;;
(p[11])	adds	src = -8, src
	add	len = len, loopcnt
	;;
	sub	src = src, sh2
	;;
	add	len = tmp, len
	add	src = sh1, src
	br.cond.sptk .cpyfew

.recovery2:
#if MEMLAT != 6
# error "MEMLAT must be 6!"
#endif
	add	tmp = -8, src
(p7)	br.cond.spnt .gotit
	;;
(p[0])	add	tmp = -8, tmp ;;
(p[1])	add	tmp = -8, tmp ;;
(p[2])	add	tmp = -8, tmp ;;
(p[3])	add	tmp = -8, tmp ;;
(p[4])	add	tmp = -8, tmp ;;
(p[5])	add	tmp = -8, tmp ;;
(p[6])	add	tmp = -8, tmp ;;
(p[7])	add	tmp = -8, tmp ;;
	ld8	r[MEMLAT+2] = [tmp] ;;
	xor	pos0[1] = r[MEMLAT+2], charx8 ;;
	czx1.r	pos0[1] = pos0[1] ;;
	cmp.ne	p7, p6 = 8, pos0[1]
(p7)	br.cond.spnt .gotit
	br.cond.sptk .back2
END(memccpy)