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+/* Vector optimized 32/64 bit S/390 version of strlen.
+ Copyright (C) 2015 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 strlen (const char *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(__strlen_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. */
+
+ vfenezb %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. */
+ blr %r14 /* 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 16 byte aligned loop. */
+.Lloop:
+ 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
+ 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
+ br %r14
+END(__strlen_vx)
+#endif /* HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc) */