diff options
Diffstat (limited to 'libc/string/ia64/strchr.S')
| -rw-r--r-- | libc/string/ia64/strchr.S | 112 |
1 files changed, 112 insertions, 0 deletions
diff --git a/libc/string/ia64/strchr.S b/libc/string/ia64/strchr.S new file mode 100644 index 000000000..24001eea6 --- /dev/null +++ b/libc/string/ia64/strchr.S @@ -0,0 +1,112 @@ +/* Optimized version of the standard strchr() function. + This file is part of the GNU C Library. + Copyright (C) 2000, 2001, 2003 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, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +/* Return: the address of the first occurence of chr in str or NULL + + Inputs: + in0: str + in1: chr + + A modified version of memchr.S, the search ends when the character is + found or the terminating null character is encountered. + + This implementation assumes little endian mode. For big endian mode, + the instruction czx1.r should be replaced by czx1.l. */ + +#include <sysdep.h> +#undef ret + +#define saved_lc r18 +#define poschr r19 +#define pos0 r20 +#define val1 r21 +#define val2 r22 +#define tmp r24 +#define chrx8 r25 +#define loopcnt r30 + +#define str in0 +#define chr in1 + +ENTRY(strchr) + .prologue + alloc r2 = ar.pfs, 2, 0, 0, 0 + .save ar.lc, saved_lc + mov saved_lc = ar.lc // save the loop counter + .body + mov ret0 = str + and tmp = 7, str // tmp = str % 8 + mux1 chrx8 = chr, @brcst + extr.u chr = chr, 0, 8 // retain only the last byte + cmp.ne p8, p0 = r0, r0 // clear p8 + ;; + sub loopcnt = 8, tmp // loopcnt = 8 - tmp + cmp.eq p6, p0 = tmp, r0 +(p6) br.cond.sptk .str_aligned;; + adds loopcnt = -1, loopcnt;; + mov ar.lc = loopcnt +.l1: + ld1 val2 = [ret0], 1 + ;; + cmp.eq p6, p0 = val2, chr + cmp.eq p7, p0 = val2, r0 +(p6) br.cond.spnt .restore_and_exit +(p7) br.cond.spnt .notfound + br.cloop.sptk .l1 +.str_aligned: + ld8 val1 = [ret0], 8;; + nop.b 0 + nop.b 0 +.l2: + ld8.s val2 = [ret0], 8 // don't bomb out here + czx1.r pos0 = val1 + xor tmp = val1, chrx8 // if val1 contains chr, tmp will + ;; // contain a zero in its position + czx1.r poschr = tmp + cmp.ne p6, p0 = 8, pos0 + ;; + cmp.ne p7, p0 = 8, poschr +(p7) br.cond.spnt .foundit +(p6) br.cond.spnt .notfound + chk.s val2, .recovery +.back: + mov val1 = val2 + br.cond.dptk .l2 +.foundit: +(p6) cmp.lt p8, p0 = pos0, poschr // we found chr and null in the word +(p8) br.cond.spnt .notfound // null was found before chr + add ret0 = ret0, poschr ;; + adds ret0 = -15, ret0 ;; // should be -16, but we decrement +.restore_and_exit: // ret0 in the next instruction + adds ret0 = -1, ret0 // ret0 was pointing 1 char too far + mov ar.lc = saved_lc // restore the loop counter + br.ret.sptk.many b0 +.notfound: + mov ret0 = r0 // return NULL if null was found + mov ar.lc = saved_lc + br.ret.sptk.many b0 +.recovery: + adds ret0 = -8, ret0;; + ld8 val2 = [ret0], 8 // bomb out here + br.cond.sptk .back +END(strchr) + +weak_alias (strchr, index) +libc_hidden_def (strchr) |