+++ /dev/null
-/* 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, see
- <http://www.gnu.org/licenses/>. */
-
-#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)
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