| /* Vector optimized 32/64 bit S/390 version of wcsncmp. |
| 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 |
| |
| /* int wcsncmp (const wchar_t *s1, const wchar_t *s2, size_t n) |
| Compare at most n characters of two strings. |
| |
| Register usage: |
| -r0=tmp |
| -r1=tmp |
| -r2=s1 |
| -r3=s2 |
| -r4=n |
| -r5=current_len |
| -v16=part of s1 |
| -v17=part of s2 |
| -v18=index of unequal |
| */ |
| ENTRY(__wcsncmp_vx) |
| .machine "z13" |
| .machinemode "zarch_nohighgprs" |
| |
| # if !defined __s390x__ |
| llgfr %r4,%r4 |
| # endif /* !defined __s390x__ */ |
| |
| clgije %r4,0,.Lend_equal /* Nothing to do if n == 0. */ |
| |
| /* Check range of n and convert to byte-count. */ |
| # ifdef __s390x__ |
| tmhh %r4,49152 /* Test bit 0 or 1 of maxlen. */ |
| lghi %r1,-4 /* Max byte-count is 18446744073709551612. */ |
| # else |
| tmlh %r4,49152 /* Test bit 0 or 1 of maxlen. */ |
| llilf %r1,4294967292 /* Max byte-count is 4294967292. */ |
| # endif /* !__s390x__ */ |
| sllg %r4,%r4,2 /* Convert character-count to byte-count. */ |
| locgrne %r4,%r1 /* Use max byte-count, if bit 0/1 was one. */ |
| |
| /* Check first character without vector load. */ |
| lghi %r5,4 /* current_len = 4 bytes. */ |
| /* Check s1/2[0]. */ |
| lt %r0,0(%r2) |
| l %r1,0(%r3) |
| je .Lend_cmp_one_char |
| crjne %r0,%r1,.Lend_cmp_one_char |
| |
| .Lloop: |
| vlbb %v17,0(%r5,%r3),6 /* Load s2 to block boundary. */ |
| vlbb %v16,0(%r5,%r2),6 /* Load s1 to block boundary. */ |
| lcbb %r0,0(%r5,%r2),6 /* Get loaded byte count of s1. */ |
| jo .Llt16_1 /* Jump away if vector not fully loaded. */ |
| lcbb %r1,0(%r5,%r3),6 /* Get loaded byte count of s2. */ |
| jo .Llt16_2 /* Jump away if vector not fully loaded. */ |
| aghi %r5,16 /* Both vectors are fully loaded. */ |
| vfenezfs %v18,%v16,%v17 /* Compare not equal with zero search. */ |
| clgrjhe %r5,%r4,.Llastcmp /* If current_len >= n ->last compare. */ |
| jno .Lfound |
| |
| vlbb %v17,0(%r5,%r3),6 |
| vlbb %v16,0(%r5,%r2),6 |
| lcbb %r0,0(%r5,%r2),6 |
| jo .Llt16_1 |
| lcbb %r1,0(%r5,%r3),6 |
| jo .Llt16_2 |
| aghi %r5,16 |
| vfenezfs %v18,%v16,%v17 |
| clgrjhe %r5,%r4,.Llastcmp |
| jno .Lfound |
| |
| vlbb %v17,0(%r5,%r3),6 |
| vlbb %v16,0(%r5,%r2),6 |
| lcbb %r0,0(%r5,%r2),6 |
| jo .Llt16_1 |
| lcbb %r1,0(%r5,%r3),6 |
| jo .Llt16_2 |
| aghi %r5,16 |
| vfenezfs %v18,%v16,%v17 |
| clgrjhe %r5,%r4,.Llastcmp |
| jno .Lfound |
| |
| vlbb %v17,0(%r5,%r3),6 |
| vlbb %v16,0(%r5,%r2),6 |
| lcbb %r0,0(%r5,%r2),6 |
| jo .Llt16_1 |
| lcbb %r1,0(%r5,%r3),6 |
| jo .Llt16_2 |
| aghi %r5,16 |
| vfenezfs %v18,%v16,%v17 |
| clgrjhe %r5,%r4,.Llastcmp |
| jno .Lfound |
| |
| j .Lloop |
| |
| .Llt16_1: |
| lcbb %r1,0(%r5,%r3),6 /* Get loaded byte count of s2. */ |
| .Llt16_2: |
| clr %r0,%r1 /* Compare logical. */ |
| locrh %r0,%r1 /* Compute minimum of bytes loaded. */ |
| nill %r0,65532 /* Align bytes loaded to full characters. */ |
| jz .Lcmp_one_char /* Jump away if no full char is available. */ |
| .Llt_cmp: |
| algfr %r5,%r0 /* Add smallest loaded bytes to current_len. */ |
| vfenezfs %v18,%v16,%v17 /* Compare not equal with zero search. */ |
| clgrj %r5,%r4,10,.Llastcmp /* If current_len >= n -> last compare */ |
| vlgvb %r1,%v18,7 /* Get not equal index or 16 if all equal. */ |
| clrjl %r1,%r0,.Lfound /* Jump away if miscompare is within |
| loaded bytes; (index < loaded-bytes) */ |
| j .Lloop |
| |
| .Lcmp_one_char: |
| /* At least one of both strings is not 4-byte aligned |
| and there is no full character before next block-boundary. |
| Compare one character to get over the boundary and |
| proceed with normal loop! */ |
| vlef %v16,0(%r5,%r2),0 /* Load one character. */ |
| lghi %r0,4 /* Loaded byte count is 4. */ |
| vlef %v17,0(%r5,%r3),0 |
| j .Llt_cmp /* Proceed with comparision. */ |
| |
| .Llastcmp: |
| /* Use comparision result only if located within first n characters. |
| %r0: loaded byte count in vreg; |
| %r5: current_len; |
| %r4: n; |
| (current_len - n): [0...16[ |
| First ignored match index: loaded bytes - (current_len-n): ]0...16] |
| */ |
| slgr %r5,%r4 /* %r5 = current_len - n. */ |
| slr %r0,%r5 /* %r0 = first ignored match index. */ |
| vlgvb %r4,%v18,7 /* Get not equal index or 16 if all equal. */ |
| clrjl %r4,%r0,.Lfound2 /* Jump away if miscompare is within |
| loaded bytes and below n bytes. */ |
| .Lend_equal: |
| lghi %r2,0 |
| br %r14 |
| |
| .Lfound: |
| /* Difference or end of string. */ |
| /* vfenezf found an unequal element or zero. |
| This instruction compares unsigned words, but wchar_t is signed. |
| Thus we have to compare the found element again. */ |
| vlgvb %r4,%v18,7 /* Extract not equal byte-index. */ |
| .Lfound2: |
| srl %r4,2 /* And convert it to character-index. */ |
| vlgvf %r0,%v16,0(%r4) /* Load character-values. */ |
| vlgvf %r1,%v17,0(%r4) |
| .Lend_cmp_one_char: |
| cr %r0,%r1 |
| je .Lend_equal |
| lghi %r2,1 |
| lghi %r1,-1 |
| locgrl %r2,%r1 |
| br %r14 |
| END(__wcsncmp_vx) |
| #endif /* HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc) */ |
