aboutsummaryrefslogtreecommitdiff
path: root/sysdeps/ia64/memccpy.S
blob: fbb21e48225e38391757f6cf5560f5649bc6a747 (plain)
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
/* Optimized version of the memccpy() function.
   This file is part of the GNU C Library.
   Copyright (C) 2000, 2001 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 Library General Public License as
   published by the Free Software Foundation; either version 2 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
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with the GNU C Library; see the file COPYING.LIB.  If not,
   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

/* 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 sh2		r28
#define	sh1		r29
#define loopcnt		r30
#define	value		r31

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

#include "softpipe.h"
	.rotr	r[MEMLAT + 3], 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
	.save ar.lc, saved_lc
        mov 	saved_lc = ar.lc	// save the loop counter
	.body
	mov 	dest = in0		// dest
	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
(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	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])	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	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]
(p7)		br.cond.spnt	.gotit
(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
	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
END(memccpy)