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Diffstat (limited to 'sysdeps/s390/multiarch/strnlen-vx.S')
| -rw-r--r-- | sysdeps/s390/multiarch/strnlen-vx.S | 134 |
1 files changed, 134 insertions, 0 deletions
diff --git a/sysdeps/s390/multiarch/strnlen-vx.S b/sysdeps/s390/multiarch/strnlen-vx.S new file mode 100644 index 0000000000..3e3a31dd9c --- /dev/null +++ b/sysdeps/s390/multiarch/strnlen-vx.S @@ -0,0 +1,134 @@ +/* Vector optimized 32/64 bit S/390 version of strnlen. + Copyright (C) 2015-2016 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 strnlen (const char *s, size_t maxlen) + Returns the number of characters in s or at most maxlen. + + Register usage: + -r1=tmp + -r2=address of string + -r3=maxlen (number of characters to be read) + -r4=tmp + -r5=current_len and return_value + -v16=part of s +*/ +ENTRY(__strnlen_vx) + .machine "z13" + .machinemode "zarch_nohighgprs" + +# if !defined __s390x__ + llgfr %r3,%r3 +# endif /* !defined __s390x__ */ + + clgfi %r3,0 /* if maxlen == 0, return 0. */ + locgre %r2,%r3 + ber %r14 + + 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. */ + llgfr %r1,%r1 /* Convert 32bit to 64bit. */ + + vfenezb %v16,%v16,%v16 /* Find element not equal with zero search. */ + clgr %r1,%r3 + locgrh %r1,%r3 /* loaded_byte_count + = min (loaded_byte_count, maxlen) */ + + vlgvb %r5,%v16,7 /* Load zero index or 16 if not found. */ + clr %r5,%r1 /* If found zero within loaded bytes? */ + locgrl %r2,%r5 /* Then copy return value. */ + blr %r14 /* And return. */ + + clgr %r1,%r3 /* If loaded_byte_count == maxlen? */ + locgre %r2,%r3 /* Then copy return value. */ + ber %r14 /* And return. */ + + /* Align s to 16 byte. */ + risbgn %r4,%r2,60,128+63,0 /* %r3 = bits 60-63 of %r2 'and' 15. */ + lghi %r5,16 /* current_len = 16. */ + slr %r5,%r4 /* Compute bytes to 16bytes boundary. */ + + lgr %r1,%r5 /* If %r5 + 64 < maxlen? -> loop64. */ + aghi %r1,64 + clgrjl %r1,%r3,.Lloop64 + + /* Find zero in max 64byte with aligned s. */ +.Llt64: + vl %v16,0(%r5,%r2) /* Load s. */ + vfenezbs %v16,%v16,%v16 /* Find element not equal with zero search. */ + je .Lfound /* Jump away if zero was found. */ + aghi %r5,16 + clgrjhe %r5,%r3,.Lfound /* current_len >= maxlen -> end. */ + vl %v16,0(%r5,%r2) + vfenezbs %v16,%v16,%v16 + je .Lfound + aghi %r5,16 + clgrjhe %r5,%r3,.Lfound + vl %v16,0(%r5,%r2) + vfenezbs %v16,%v16,%v16 + je .Lfound + aghi %r5,16 + clgrjhe %r5,%r3,.Lfound + vl %v16,0(%r5,%r2) + vfenezbs %v16,%v16,%v16 + j .Lfound + +.Lfound48: + aghi %r5,16 +.Lfound32: + aghi %r5,16 +.Lfound16: + aghi %r5,16 +.Lfound: + vlgvb %r4,%v16,7 /* Load byte index of zero or 16 if no zero. */ + algr %r5,%r4 + + clgr %r5,%r3 + locgrh %r5,%r3 /* Return min (current_len, maxlen). */ + lgr %r2,%r5 + br %r14 + + /* Find zero in 16 byte aligned loop. */ +.Lloop64: + vl %v16,0(%r5,%r2) /* Load s. */ + vfenezbs %v16,%v16,%v16 /* Find element not equal with zero search. */ + je .Lfound /* Jump away if zero was found. */ + vl %v16,16(%r5,%r2) + vfenezbs %v16,%v16,%v16 + je .Lfound16 + vl %v16,32(%r5,%r2) + vfenezbs %v16,%v16,%v16 + je .Lfound32 + vl %v16,48(%r5,%r2) + vfenezbs %v16,%v16,%v16 + je .Lfound48 + + aghi %r5,64 + lgr %r1,%r5 /* If %r5 + 64 < maxlen? -> loop64. */ + aghi %r1,64 + clgrjl %r1,%r3,.Lloop64 + + j .Llt64 +END(__strnlen_vx) +#endif /* HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc) */ |