1 /* rawmemchr (str, ch) -- Return pointer to first occurrence of CH in STR.
3 Copyright (C) 1999-2013 Free Software Foundation, Inc.
4 This file is part of the GNU C Library.
5 Contributed by Jakub Jelinek <jj@ultra.linux.cz>.
6 This version is developed using the same algorithm as the fast C
7 version which carries the following introduction:
8 Based on strlen implementation by Torbjorn Granlund (tege@sics.se),
9 with help from Dan Sahlin (dan@sics.se) and
10 commentary by Jim Blandy (jimb@ai.mit.edu);
11 adaptation to memchr suggested by Dick Karpinski (dick@cca.ucsf.edu),
12 and implemented by Roland McGrath (roland@ai.mit.edu).
14 The GNU C Library is free software; you can redistribute it and/or
15 modify it under the terms of the GNU Lesser General Public
16 License as published by the Free Software Foundation; either
17 version 2.1 of the License, or (at your option) any later version.
19 The GNU C Library is distributed in the hope that it will be useful,
20 but WITHOUT ANY WARRANTY; without even the implied warranty of
21 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
22 Lesser General Public License for more details.
24 You should have received a copy of the GNU Lesser General Public
25 License along with the GNU C Library; if not, see
26 <http://www.gnu.org/licenses/>. */
33 .register %g2, #scratch
34 .register %g3, #scratch
37 /* Normally, this uses
38 ((xword - 0x0101010101010101) & 0x8080808080808080) test
39 to find out if any byte in xword could be zero. This is fast, but
40 also gives false alarm for any byte in range 0x81-0xff. It does
41 not matter for correctness, as if this test tells us there could
42 be some zero byte, we check it byte by byte, but if bytes with
43 high bits set are common in the strings, then this will give poor
44 performance. You can #define EIGHTBIT_NOT_RARE and the algorithm
45 will use one tick slower, but more precise test
46 ((xword - 0x0101010101010101) & (~xword) & 0x8080808080808080),
47 which does not give any false alarms (but if some bits are set,
48 one cannot assume from it which bytes are zero and which are not).
49 It is yet to be measured, what is the correct default for glibc
50 in these days for an average user.
56 and %o1, 0xff, %o1 /* IEU0 Group */
57 sethi %hi(0x01010101), %g1 /* IEU1 */
58 ldub [%o0], %o3 /* Load */
59 sll %o1, 8, %o4 /* IEU0 Group */
61 or %g1, %lo(0x01010101), %g1 /* IEU1 */
62 sllx %g1, 32, %g2 /* IEU0 Group */
63 or %o4, %o1, %o4 /* IEU1 */
64 andcc %o0, 7, %g0 /* IEU1 Group */
66 sll %o4, 16, %g5 /* IEU0 */
67 or %o4, %g5, %o4 /* IEU0 Group */
68 or %g1, %g2, %g1 /* IEU1 */
69 bne,pn %icc, 32f /* CTI */
71 sllx %o4, 32, %g5 /* IEU0 Group */
72 cmp %o3, %o1 /* IEU1 */
73 be,pn %icc, 30f /* CTI */
74 sllx %g1, 7, %g2 /* IEU0 Group */
76 18: ldx [%o0], %o3 /* Load */
77 or %o4, %g5, %o4 /* IEU1 */
78 add %o0, 8, %o0 /* IEU0 Group */
79 19: xor %o3, %o4, %o3 /* IEU0 Group */
81 sub %o3, %g1, %o2 /* IEU0 Group */
82 #ifdef EIGHTBIT_NOT_RARE
83 andn %o2, %o3, %o5 /* IEU0 Group */
84 ldxa [%o0] ASI_PNF, %o3 /* Load */
85 andcc %o5, %g2, %g0 /* IEU1 Group */
87 ldxa [%o0] ASI_PNF, %o3 /* Load */
88 andcc %o2, %g2, %g0 /* IEU1 Group */
90 be,pt %xcc, 19b /* CTI */
92 add %o0, 8, %o0 /* IEU0 */
93 addcc %o2, %g1, %g3 /* IEU1 Group */
94 srlx %o2, 32, %o2 /* IEU0 */
95 20: andcc %o2, %g2, %g0 /* IEU1 Group */
97 be,pn %xcc, 21f /* CTI */
98 srlx %g3, 56, %o2 /* IEU0 */
99 andcc %o2, 0xff, %g0 /* IEU1 Group */
100 be,pn %icc, 29f /* CTI */
102 srlx %g3, 48, %o2 /* IEU0 */
103 andcc %o2, 0xff, %g0 /* IEU1 Group */
104 be,pn %icc, 28f /* CTI */
105 srlx %g3, 40, %o2 /* IEU0 */
107 andcc %o2, 0xff, %g0 /* IEU1 Group */
108 be,pn %icc, 27f /* CTI */
109 srlx %g3, 32, %o2 /* IEU0 */
110 andcc %o2, 0xff, %g0 /* IEU1 Group */
112 be,pn %icc, 26f /* CTI */
113 21: srlx %g3, 24, %o2 /* IEU0 */
114 andcc %o2, 0xff, %g0 /* IEU1 Group */
115 be,pn %icc, 25f /* CTI */
117 srlx %g3, 16, %o2 /* IEU0 */
118 andcc %o2, 0xff, %g0 /* IEU1 Group */
119 be,pn %icc, 24f /* CTI */
120 srlx %g3, 8, %o2 /* IEU0 */
122 andcc %o2, 0xff, %g0 /* IEU1 Group */
123 be,pn %icc, 23f /* CTI */
124 xor %o3, %o4, %o3 /* IEU0 */
125 andcc %g3, 0xff, %g0 /* IEU1 Group */
127 be,pn %icc, 22f /* CTI */
128 sub %o3, %g1, %o2 /* IEU0 */
129 ldxa [%o0] ASI_PNF, %o3 /* Load */
130 andcc %o2, %g2, %g0 /* IEU1 Group */
132 be,pt %xcc, 19b /* CTI */
133 add %o0, 8, %o0 /* IEU0 */
134 addcc %o2, %g1, %g3 /* IEU1 Group */
135 ba,pt %xcc, 20b /* CTI */
137 srlx %o2, 32, %o2 /* IEU0 */
140 22: retl /* CTI+IEU1 Group */
141 add %o0, -9, %o0 /* IEU0 */
142 23: retl /* CTI+IEU1 Group */
143 add %o0, -10, %o0 /* IEU0 */
145 24: retl /* CTI+IEU1 Group */
146 add %o0, -11, %o0 /* IEU0 */
147 25: retl /* CTI+IEU1 Group */
148 add %o0, -12, %o0 /* IEU0 */
150 26: retl /* CTI+IEU1 Group */
151 add %o0, -13, %o0 /* IEU0 */
152 27: retl /* CTI+IEU1 Group */
153 add %o0, -14, %o0 /* IEU0 */
155 28: retl /* CTI+IEU1 Group */
156 add %o0, -15, %o0 /* IEU0 */
157 29: retl /* CTI+IEU1 Group */
158 add %o0, -16, %o0 /* IEU0 */
160 30: retl /* CTI+IEU1 Group */
164 32: andcc %o0, 7, %g0 /* IEU1 Group */
165 be,a,pn %icc, 18b /* CTI */
166 sllx %g1, 7, %g2 /* IEU0 */
167 add %o0, 1, %o0 /* IEU0 Group */
169 cmp %o3, %o1 /* IEU1 */
170 bne,a,pt %icc, 32b /* CTI */
171 lduba [%o0] ASI_PNF, %o3 /* Load */
172 retl /* CTI+IEU1 Group */
174 add %o0, -1, %o0 /* IEU0 */
177 libc_hidden_def (__rawmemchr)
178 weak_alias (__rawmemchr, rawmemchr)