[thirdparty/glibc.git] / sysdeps / s390 / multiarch / strnlen-vx.S

/* 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) */
Commit	Line	Data
fcf40ebe	1	/* Vector optimized 32/64 bit S/390 version of strnlen.
f7a9f785	2	Copyright (C) 2015-2016 Free Software Foundation, Inc.
fcf40ebe SL	3	This file is part of the GNU C Library.
	4
	5	The GNU C Library is free software; you can redistribute it and/or
	6	modify it under the terms of the GNU Lesser General Public
	7	License as published by the Free Software Foundation; either
	8	version 2.1 of the License, or (at your option) any later version.
	9
	10	The GNU C Library is distributed in the hope that it will be useful,
	11	but WITHOUT ANY WARRANTY; without even the implied warranty of
	12	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	13	Lesser General Public License for more details.
	14
	15	You should have received a copy of the GNU Lesser General Public
	16	License along with the GNU C Library; if not, see
	17	<http://www.gnu.org/licenses/>. */
	18
	19	#if defined HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc)
	20
	21	# include "sysdep.h"
	22	# include "asm-syntax.h"
	23
	24	.text
	25
	26	/* size_t strnlen (const char *s, size_t maxlen)
	27	Returns the number of characters in s or at most maxlen.
	28
	29	Register usage:
	30	-r1=tmp
	31	-r2=address of string
	32	-r3=maxlen (number of characters to be read)
	33	-r4=tmp
	34	-r5=current_len and return_value
	35	-v16=part of s
	36	*/
	37	ENTRY(__strnlen_vx)
	38	.machine "z13"
	39	.machinemode "zarch_nohighgprs"
	40
	41	# if !defined __s390x__
	42	llgfr %r3,%r3
	43	# endif /* !defined __s390x__ */
	44
	45	clgfi %r3,0 /* if maxlen == 0, return 0. */
	46	locgre %r2,%r3
	47	ber %r14
	48
	49	vlbb %v16,0(%r2),6 /* Load s until next 4k-byte boundary. */
	50	lcbb %r1,0(%r2),6 /* Get bytes to 4k-byte boundary or 16. */
	51	llgfr %r1,%r1 /* Convert 32bit to 64bit. */
	52
	53	vfenezb %v16,%v16,%v16 /* Find element not equal with zero search. */
	54	clgr %r1,%r3
	55	locgrh %r1,%r3 /* loaded_byte_count
	56	= min (loaded_byte_count, maxlen) */
	57
	58	vlgvb %r5,%v16,7 /* Load zero index or 16 if not found. */
	59	clr %r5,%r1 /* If found zero within loaded bytes? */
	60	locgrl %r2,%r5 /* Then copy return value. */
	61	blr %r14 /* And return. */
	62
	63	clgr %r1,%r3 /* If loaded_byte_count == maxlen? */
	64	locgre %r2,%r3 /* Then copy return value. */
	65	ber %r14 /* And return. */
	66
67	/* Align s to 16 byte. */
68	risbgn %r4,%r2,60,128+63,0 /* %r3 = bits 60-63 of %r2 'and' 15. */
69	lghi %r5,16 /* current_len = 16. */
70	slr %r5,%r4 /* Compute bytes to 16bytes boundary. */
71
72	lgr %r1,%r5 /* If %r5 + 64 < maxlen? -> loop64. */
73	aghi %r1,64
74	clgrjl %r1,%r3,.Lloop64
75
76	/* Find zero in max 64byte with aligned s. */
77	.Llt64:
78	vl %v16,0(%r5,%r2) /* Load s. */
79	vfenezbs %v16,%v16,%v16 /* Find element not equal with zero search. */
80	je .Lfound /* Jump away if zero was found. */
81	aghi %r5,16
82	clgrjhe %r5,%r3,.Lfound /* current_len >= maxlen -> end. */
83	vl %v16,0(%r5,%r2)
84	vfenezbs %v16,%v16,%v16
85	je .Lfound
86	aghi %r5,16
87	clgrjhe %r5,%r3,.Lfound
88	vl %v16,0(%r5,%r2)
89	vfenezbs %v16,%v16,%v16
90	je .Lfound
91	aghi %r5,16
92	clgrjhe %r5,%r3,.Lfound
93	vl %v16,0(%r5,%r2)
94	vfenezbs %v16,%v16,%v16
95	j .Lfound
96
97	.Lfound48:
98	aghi %r5,16
99	.Lfound32:
100	aghi %r5,16
101	.Lfound16:
102	aghi %r5,16
103	.Lfound:
104	vlgvb %r4,%v16,7 /* Load byte index of zero or 16 if no zero. */
105	algr %r5,%r4
106
107	clgr %r5,%r3
108	locgrh %r5,%r3 /* Return min (current_len, maxlen). */
109	lgr %r2,%r5
110	br %r14
111
112	/* Find zero in 16 byte aligned loop. */
113	.Lloop64:
114	vl %v16,0(%r5,%r2) /* Load s. */
115	vfenezbs %v16,%v16,%v16 /* Find element not equal with zero search. */
116	je .Lfound /* Jump away if zero was found. */
117	vl %v16,16(%r5,%r2)
118	vfenezbs %v16,%v16,%v16
119	je .Lfound16
120	vl %v16,32(%r5,%r2)
121	vfenezbs %v16,%v16,%v16
122	je .Lfound32
123	vl %v16,48(%r5,%r2)
124	vfenezbs %v16,%v16,%v16
125	je .Lfound48
126
127	aghi %r5,64
128	lgr %r1,%r5 /* If %r5 + 64 < maxlen? -> loop64. */
129	aghi %r1,64
130	clgrjl %r1,%r3,.Lloop64
131
132	j .Llt64
133	END(__strnlen_vx)
134	#endif /* HAVE_S390_VX_ASM_SUPPORT && IS_IN (libc) */