| /* Vector optimized 32/64 bit S/390 version of wcslen. |
| Copyright (C) 2015-2018 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| |
| 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/>. */ |
| |
| #if defined HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc) |
| |
| # include "sysdep.h" |
| # include "asm-syntax.h" |
| |
| .text |
| |
| /* size_t wcslen (const wchar_t *s) |
| Returns length of string s. |
| |
| Register usage: |
| -r1=bytes to 4k-byte boundary |
| -r2=s |
| -r3=tmp |
| -r4=tmp |
| -r5=current_len and return_value |
| -v16=part of s |
| */ |
| ENTRY(__wcslen_vx) |
| .machine "z13" |
| .machinemode "zarch_nohighgprs" |
| |
| vlbb %v16,0(%r2),6 /* Load s until next 4k-byte boundary. */ |
| lcbb %r1,0(%r2),6 /* Get bytes to 4k-byte boundary or 16. */ |
| |
| tmll %r2,3 /* Test if s is 4-byte aligned? */ |
| jne .Lfallback /* And use common-code variant if not. */ |
| |
| vfenezf %v16,%v16,%v16 /* Find element not equal with zero search. */ |
| vlgvb %r4,%v16,7 /* Load zero index or 16 if not found. */ |
| clr %r4,%r1 /* If found zero within loaded bytes? */ |
| locgrl %r2,%r4 /* Then copy return value. */ |
| jl .Lend /* And return. */ |
| |
| /* Align s to 16 byte. */ |
| risbgn %r3,%r2,60,128+63,0 /* %r3 = bits 60-63 of %r2 'and' 15. */ |
| lghi %r5,16 /* current_len = 16. */ |
| slr %r5,%r3 /* Compute bytes to 16bytes boundary. */ |
| |
| /* Find zero in 16byte aligned loop. */ |
| .Lloop: |
| vl %v16,0(%r5,%r2) /* Load s. */ |
| vfenezfs %v16,%v16,%v16 /* Find element not equal with zero search. */ |
| je .Lfound /* Jump away if zero was found. */ |
| vl %v16,16(%r5,%r2) |
| vfenezfs %v16,%v16,%v16 |
| je .Lfound16 |
| vl %v16,32(%r5,%r2) |
| vfenezfs %v16,%v16,%v16 |
| je .Lfound32 |
| vl %v16,48(%r5,%r2) |
| vfenezfs %v16,%v16,%v16 |
| je .Lfound48 |
| |
| aghi %r5,64 |
| j .Lloop /* No zero found -> loop. */ |
| |
| .Lfound48: |
| aghi %r5,16 |
| .Lfound32: |
| aghi %r5,16 |
| .Lfound16: |
| aghi %r5,16 |
| .Lfound: |
| vlgvb %r2,%v16,7 /* Load byte index of zero. */ |
| algr %r2,%r5 |
| .Lend: |
| srlg %r2,%r2,2 /* Convert byte-count to character-count. */ |
| br %r14 |
| .Lfallback: |
| jg __wcslen_c |
| END(__wcslen_vx) |
| #endif /* HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc) */ |
