| /* Determine the length of a string. For SPARC v9. |
| Copyright (C) 1998, 1999, 2003 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| Contributed by Jan Vondrak <jvon4518@ss1000.ms.mff.cuni.cz> and |
| Jakub Jelinek <jj@ultra.linux.cz>. |
| |
| 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. */ |
| |
| #include <asm/asi.h> |
| |
| /* Normally, this uses |
| ((xword - 0x0101010101010101) & 0x8080808080808080) test |
| to find out if any byte in xword could be zero. This is fast, but |
| also gives false alarm for any byte in range 0x81-0xff. It does |
| not matter for correctness, as if this test tells us there could |
| be some zero byte, we check it byte by byte, but if bytes with |
| high bits set are common in the strings, then this will give poor |
| performance. You can #define EIGHTBIT_NOT_RARE and the algorithm |
| will use one tick slower, but more precise test |
| ((xword - 0x0101010101010101) & (~xword) & 0x8080808080808080), |
| which does not give any false alarms (but if some bits are set, |
| one cannot assume from it which bytes are zero and which are not). |
| It is yet to be measured, what is the correct default for glibc |
| in these days for an average user. |
| */ |
| |
| .text |
| .align 32 |
| ENTRY(strlen) |
| sethi %hi(0x01010101), %g1 /* IEU0 Group */ |
| ldub [%o0], %o3 /* Load */ |
| or %g1, %lo(0x01010101), %g1 /* IEU0 Group */ |
| mov %o0, %o1 /* IEU1 */ |
| |
| sllx %g1, 32, %g4 /* IEU0 Group */ |
| andcc %o0, 7, %g0 /* IEU1 */ |
| or %g1, %g4, %g1 /* IEU0 Group */ |
| brz,pn %o3, 13f /* CTI+IEU1 */ |
| |
| sllx %g1, 7, %g4 /* IEU0 Group */ |
| bne,a,pn %icc, 15f /* CTI */ |
| add %o0, 1, %o0 /* IEU1 */ |
| /* %g1 = 0x0101010101010101 * |
| * %g4 = 0x8080808080808080 * |
| * %o0 = string pointer * |
| * %o1 = start of string */ |
| 1: ldx [%o0], %o3 /* Load Group */ |
| |
| add %o0, 8, %o0 /* IEU1 */ |
| 2: sub %o3, %g1, %o2 /* IEU0 Group */ |
| #ifdef EIGHTBIT_NOT_RARE |
| andn %o2, %o3, %o5 /* IEU0 Group */ |
| ldxa [%o0] ASI_PNF, %o3 /* Load */ |
| andcc %o5, %g4, %g0 /* IEU1 Group */ |
| #else |
| ldxa [%o0] ASI_PNF, %o3 /* Load */ |
| andcc %o2, %g4, %g0 /* IEU1 Group */ |
| #endif |
| |
| be,pt %xcc, 2b /* CTI */ |
| add %o0, 8, %o0 /* IEU0 */ |
| addcc %o2, %g1, %g5 /* IEU1 Group */ |
| #ifdef EIGHTBIT_NOT_RARE |
| srlx %o5, 32, %o5 /* IEU0 */ |
| |
| 3: andcc %o5, %g4, %g0 /* IEU1 Group */ |
| #else |
| srlx %o2, 32, %o2 /* IEU0 */ |
| |
| 3: andcc %o2, %g4, %g0 /* IEU1 Group */ |
| #endif |
| be,pn %xcc, 4f /* CTI */ |
| srlx %g5, 56, %o2 /* IEU0 */ |
| andcc %o2, 0xff, %g0 /* IEU1 Group */ |
| |
| be,pn %icc, 12f /* CTI */ |
| srlx %g5, 48, %o2 /* IEU0 */ |
| andcc %o2, 0xff, %g0 /* IEU1 Group */ |
| be,pn %icc, 11f /* CTI */ |
| |
| srlx %g5, 40, %o2 /* IEU0 */ |
| andcc %o2, 0xff, %g0 /* IEU1 Group */ |
| be,pn %icc, 10f /* CTI */ |
| srlx %g5, 32, %o2 /* IEU0 */ |
| |
| andcc %o2, 0xff, %g0 /* IEU1 Group */ |
| be,pn %icc, 9f /* CTI */ |
| 4: srlx %g5, 24, %o2 /* IEU0 */ |
| andcc %o2, 0xff, %g0 /* IEU1 Group */ |
| |
| be,pn %icc, 8f /* CTI */ |
| srlx %g5, 16, %o2 /* IEU0 */ |
| andcc %o2, 0xff, %g0 /* IEU1 Group */ |
| be,pn %icc, 7f /* CTI */ |
| |
| srlx %g5, 8, %o2 /* IEU0 */ |
| andcc %o2, 0xff, %g0 /* IEU1 Group */ |
| be,pn %icc, 6f /* CTI */ |
| sub %o3, %g1, %o2 /* IEU0 */ |
| |
| andcc %g5, 0xff, %g0 /* IEU1 Group */ |
| be,pn %icc, 5f /* CTI */ |
| ldxa [%o0] ASI_PNF, %o3 /* Load */ |
| andcc %o2, %g4, %g0 /* IEU1 Group */ |
| |
| be,pt %xcc, 2b /* CTI */ |
| add %o0, 8, %o0 /* IEU0 */ |
| addcc %o2, %g1, %g5 /* IEU1 Group */ |
| ba,pt %xcc, 3b /* CTI */ |
| |
| srlx %o2, 32, %o2 /* IEU0 */ |
| 5: add %o0, -9, %o0 /* IEU0 Group */ |
| retl /* CTI+IEU1 Group */ |
| sub %o0, %o1, %o0 /* IEU0 */ |
| |
| 6: add %o0, -10, %o0 /* IEU0 Group */ |
| retl /* CTI+IEU1 Group */ |
| sub %o0, %o1, %o0 /* IEU0 */ |
| 7: add %o0, -11, %o0 /* IEU0 Group */ |
| |
| retl /* CTI+IEU1 Group */ |
| sub %o0, %o1, %o0 /* IEU0 */ |
| 8: add %o0, -12, %o0 /* IEU0 Group */ |
| retl /* CTI+IEU1 Group */ |
| |
| sub %o0, %o1, %o0 /* IEU0 */ |
| 9: add %o0, -13, %o0 /* IEU0 Group */ |
| retl /* CTI+IEU1 Group */ |
| sub %o0, %o1, %o0 /* IEU0 */ |
| |
| 10: add %o0, -14, %o0 /* IEU0 Group */ |
| retl /* CTI+IEU1 Group */ |
| sub %o0, %o1, %o0 /* IEU0 */ |
| 11: add %o0, -15, %o0 /* IEU0 Group */ |
| |
| retl /* CTI+IEU1 Group */ |
| sub %o0, %o1, %o0 /* IEU0 */ |
| 12: add %o0, -16, %o0 /* IEU0 Group */ |
| retl /* CTI+IEU1 Group */ |
| |
| sub %o0, %o1, %o0 /* IEU0 */ |
| 13: retl /* CTI+IEU1 Group */ |
| mov 0, %o0 /* IEU0 */ |
| nop |
| |
| 15: ldub [%o0], %o3 /* Load Group */ |
| 16: andcc %o0, 7, %g0 /* IEU1 */ |
| be,pn %icc, 1b /* CTI */ |
| nop /* IEU0 Group */ |
| |
| add %o0, 1, %o0 /* IEU1 */ |
| andcc %o3, 0xff, %g0 /* IEU1 Group */ |
| bne,a,pt %icc, 16b /* CTI */ |
| lduba [%o0] ASI_PNF, %o3 /* Load */ |
| |
| add %o0, -1, %o0 /* IEU0 Group */ |
| retl /* CTI+IEU1 Group */ |
| sub %o0, %o1, %o0 /* IEU0 */ |
| END(strlen) |
| libc_hidden_def(strlen) |