/* Vector Optimized 32/64 bit S/390 version of wmemcmp.

   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/>.  */

#include <ifunc-wmemcmp.h>

#if HAVE_WMEMCMP_Z13

# include "sysdep.h"

# include "asm-syntax.h"

	.text

/* int wmemcmp (const wchar_t *s1, const wchar_t *s2, size_t n)

   Compare at most n characters of two wchar_t-arrays.

   Register usage:

   -r0=tmp

   -r1=number of blocks

   -r2=s1

   -r3=s2

   -r4=n

   -r5=current_len

   -v16=part of s1

   -v17=part of s2

   -v18=index of unequal

*/

ENTRY(WMEMCMP_Z13)

	.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 maxlen 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.  */

	lghi	%r5,0		/* current_len = 0.  */

	clgijh	%r4,16,.Lgt16

.Lremaining:

	aghi	%r4,-1		/* vstl needs highest index.  */

	vll	%v16,%r4,0(%r2)

	vll	%v17,%r4,0(%r3)

	vfenef	%v18,%v16,%v17	/* Compare not equal.  */

	vlgvb	%r1,%v18,7	/* Load unequal index or 16 if not found.  */

	clrj	%r1,%r4,12,.Lfound2 /* r1 <= r4 -> unequal within loaded

					bytes.  */

.Lend_equal:

	lghi	%r2,0

	br	%r14

.Lfound:

	/* 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	%r1,%v18,7	/* Extract not equal byte-index.  */

.Lfound2:

	srl	%r1,2		/* And convert it to character-index.  */

	vlgvf	%r0,%v16,0(%r1)	/* Load character-values.  */

	vlgvf	%r1,%v17,0(%r1)

	cr	%r0,%r1

	je	.Lend_equal

	lghi	%r2,1

	lghi	%r1,-1

	locgrl	%r2,%r1

	br	%r14

.Lgt16:

	clgijh	%r4,64,.Lpreloop64

.Lpreloop16:

	srlg	%r1,%r4,4	/* Split into 16byte blocks */

.Lloop16:

	vl	%v16,0(%r5,%r2)

	vl	%v17,0(%r5,%r3)

	aghi	%r5,16

	vfenefs	%v18,%v16,%v17	/* Compare not equal.  */

	jno	.Lfound

	brctg	%r1,.Lloop16	/* Loop until all blocks are processed.  */

	llgfr	%r4,%r4

	nilf	%r4,15		/* Get remaining bytes */

	locgre	%r2,%r4

	ber	%r14

	la	%r2,0(%r5,%r2)

	la	%r3,0(%r5,%r3)

	j	.Lremaining

.Lpreloop64:

	srlg	%r1,%r4,6	/* Split into 64byte blocks */

.Lloop64:

	vl	%v16,0(%r5,%r2)

	vl	%v17,0(%r5,%r3)

	vfenefs	%v18,%v16,%v17	/* Compare not equal.  */

	jno	.Lfound

	vl	%v16,16(%r5,%r2)

	vl	%v17,16(%r5,%r3)

	vfenefs	%v18,%v16,%v17

	jno	.Lfound

	vl	%v16,32(%r5,%r2)

	vl	%v17,32(%r5,%r3)

	vfenefs	%v18,%v16,%v17

	jno	.Lfound

	vl	%v16,48(%r5,%r2)

	vl	%v17,48(%r5,%r3)

	aghi	%r5,64

	vfenefs	%v18,%v16,%v17

	jno	.Lfound

	brctg	%r1,.Lloop64	/* Loop until all blocks are processed.  */

	llgfr	%r4,%r4

	nilf	%r4,63		/* Get remaining bytes */

	locgre	%r2,%r4

	ber	%r14

	clgijh	%r4,16,.Lpreloop16

	la	%r2,0(%r5,%r2)

	la	%r3,0(%r5,%r3)

	j	.Lremaining

END(WMEMCMP_Z13)

# if ! HAVE_WMEMCMP_IFUNC

strong_alias (WMEMCMP_Z13, wmemcmp)

# endif

#endif