1 /* Optimized version of the standard strchr() function.
2 This file is part of the GNU C Library.
3 Copyright (C) 2000 Free Software Foundation, Inc.
4 Contributed by Dan Pop <Dan.Pop@cern.ch>.
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Library General Public License as
8 published by the Free Software Foundation; either version 2 of the
9 License, or (at your option) any later version.
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Library General Public License for more details.
16 You should have received a copy of the GNU Library General Public
17 License along with the GNU C Library; see the file COPYING.LIB. If not,
18 write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
21 /* Return: the address of the first occurence of chr in str or NULL
27 A modified version of memchr.S, the search ends when the character is
28 found or the terminating null character is encountered.
30 This implementation assumes little endian mode. For big endian mode,
31 the instruction czx1.r should be replaced by czx1.l. */
50 alloc saved_pfs = ar.pfs, 2, 0, 0, 0
51 mov saved_lc = ar.lc // save the loop counter
53 and tmp = 7, str // tmp = str % 8
54 mux1 chrx8 = chr, @brcst
55 extr.u chr = chr, 0, 8 // retain only the last byte
56 cmp.ne p8, p0 = r0, r0 // clear p8
58 sub loopcnt = 8, tmp // loopcnt = 8 - tmp
59 cmp.eq p6, p0 = tmp, r0
60 (p6) br.cond.sptk .str_aligned;;
61 adds loopcnt = -1, loopcnt;;
66 cmp.eq p6, p0 = val2, chr
67 cmp.eq p7, p0 = val2, r0
68 (p6) br.cond.spnt .restore_and_exit
69 (p7) br.cond.spnt .notfound
72 ld8 val1 = [ret0], 8;;
76 ld8.s val2 = [ret0], 8 // don't bomb out here
78 xor tmp = val1, chrx8 // if val1 contains chr, tmp will
79 ;; // contain a zero in its position
81 cmp.ne p6, p0 = 8, pos0
83 cmp.ne p7, p0 = 8, poschr
84 (p7) br.cond.spnt .foundit
85 (p6) br.cond.spnt .notfound
91 (p6) cmp.lt p8, p0 = pos0, poschr // we found chr and null in the word
92 (p8) br.cond.spnt .notfound // null was found before chr
93 add ret0 = ret0, poschr ;;
94 adds ret0 = -15, ret0 ;; // should be -16, but we decrement
95 .restore_and_exit: // ret0 in the next instruction
96 adds ret0 = -1, ret0 // ret0 was pointing 1 char too far
97 mov ar.pfs = saved_pfs // restore the PFS
98 mov ar.lc = saved_lc // restore the loop counter
101 mov ret0 = r0 // return NULL if null was found
102 mov ar.pfs = saved_pfs // first
106 adds ret0 = -8, ret0;;
107 ld8 val2 = [ret0], 8 // bomb out here
111 weak_alias(strchr, index)