/* Vector optimized 32/64 bit S/390 version of memmem.

   Copyright (C) 2019 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-memmem.h>

#if HAVE_MEMMEM_ARCH13

# include "sysdep.h"

# include "asm-syntax.h"

	.text

/* void *memmem(const void *haystack=r2, size_t haystacklen=r3,

		const void *needle=r4, size_t needlelen=r5);

   Locate a substring.  */

ENTRY(MEMMEM_ARCH13)

	.machine "arch13"

	.machinemode "zarch_nohighgprs"

# if ! defined __s390x__

	llgfr	%r3,%r3

	llgfr	%r5,%r5

	llgfr	%r4,%r4

	llgfr	%r2,%r2

# endif /* ! defined __s390x__ */

	clgrjl	%r3,%r5,.Lend_no_match	/* Haystack < needle?  */

	/* Jump to fallback if needle > 9.  See also strstr-arch13.S.  */

# if ! HAVE_MEMMEM_Z13

#  error The arch13 variant of memmem needs the z13 variant of memmem!

# endif

	clgfi	%r5,9

	jh	MEMMEM_Z13

	aghik	%r0,%r5,-1		/* vll needs highest index.  */

	bc	4,0(%r14)		/* cc==1: return if needle-len == 0.  */

	vll	%v18,%r0,0(%r4)		/* Load needle.  */

	vlvgb	%v19,%r5,7		/* v19[7] contains length of needle.  */

	clgijh	%r3,16,.Lhaystack_larger_16

.Lhaystack_smaller_16_on_bb:

	aghik	%r0,%r3,-1		/* vll needs highest index.  */

	vll	%v16,%r0,0(%r2)		/* Load haystack.  */

.Lhaystack_smaller_16:

	sgr	%r3,%r5			/* r3 = largest valid match-index.  */

	jl	.Lend_no_match		/* Haystack-len < needle-len?  */

	vstrs	%v20,%v16,%v18,%v19,0,0

	/* Vector string search without zero search where v20 will contain

	   the index of a partial/full match or 16 (index is named k).

	   cc=0 (no match; k=16): .Lend_no_match

	   cc=1 (only available with zero-search): Ignore

	   cc=2 (full match; k<16): Needle found, but could be beyond haystack!

	   cc=3 (partial match; k<16): Always at end of v16 and thus beyond!  */

	brc	9,.Lend_no_match	/* Jump away if cc == 0 || cc == 3.  */

	vlgvb	%r1,%v20,7

	/* Verify that the full-match (cc=2) is valid!  */

	clgrjh	%r1,%r3,.Lend_no_match	/* Jump away if match is beyond.  */

	la	%r2,0(%r1,%r2)

	br	%r14

.Lend_no_match:

	lghi	%r2,0

	br	%r14

.Lhaystack_larger_16:

	vl	%v16,0(%r2)

	lghi	%r1,17

	lay	%r4,-16(%r3,%r2)	/* Boundary for loading with vl.  */

	lay	%r0,-64(%r3,%r2)	/* Boundary for loading with 4xvl.  */

	/* See also strstr-arch13.S:

	   min-skip-partial-match-index = (16 - n_len) + 1  */

	sgr	%r1,%r5

	clgfi	%r3,64			/* Set Boundary to zero ...  */

	la	%r3,0(%r3,%r2)

	locghil	%r0,0			/* ... if haystack < 64bytes.  */

	jh	.Lloop64

.Lloop:

	la	%r2,16(%r2)

	/* Vector string search with zero search.  cc=0 => no match.  */

	vstrs	%v20,%v16,%v18,%v19,0,0

	jne	.Lloop_vstrs_nonzero_cc

	clgrjh	%r2,%r4,.Lhaystack_too_small

.Lloop16:

	vl	%v16,0(%r2)

	la	%r2,16(%r2)

	vstrs	%v20,%v16,%v18,%v19,0,0

	jne	.Lloop_vstrs_nonzero_cc

	clgrjle	%r2,%r4,.Lloop16

.Lhaystack_too_small:

	sgr	%r3,%r2			/* r3 = (haystack + len) - curr_pos  */

	je	.Lend_no_match		/* Remaining haystack is empty.  */

	lcbb	%r0,0(%r2),6

	jo	.Lhaystack_smaller_16_on_bb

	vl	%v16,0(%r2)		/* Load haystack.  */

	j	.Lhaystack_smaller_16

.Lend_match_found:

	vlgvb	%r4,%v20,7

	sgr	%r2,%r1

	la	%r2,0(%r4,%r2)

	br	%r14

.Lloop_vstrs_nonzero_cc32:

	la	%r2,16(%r2)

.Lloop_vstrs_nonzero_cc16:

	la	%r2,16(%r2)

.Lloop_vstrs_nonzero_cc0:

	la	%r2,16(%r2)

.Lloop_vstrs_nonzero_cc:

	lay	%r2,-16(%r1,%r2)	/* Compute next load address.  */

	jh	.Lend_match_found	/* cc == 2 (full match)  */

	clgrjh	%r2,%r4,.Lhaystack_too_small

	vl	%v16,0(%r2)

.Lloop_vstrs_nonzero_cc_loop:

	la	%r2,0(%r1,%r2)

	vstrs	%v20,%v16,%v18,%v19,0,0

	jh	.Lend_match_found

	clgrjh	%r2,%r4,.Lhaystack_too_small

	vl	%v16,0(%r2)		/* Next part of haystack.  */

	jo	.Lloop_vstrs_nonzero_cc_loop

	/* Case: no-match.  */

	clgrjh	%r2,%r0,.Lloop	/* Jump away if haystack has less than 64b.  */

.Lloop64:

	vstrs	%v20,%v16,%v18,%v19,0,0

	jne	.Lloop_vstrs_nonzero_cc0

	vl	%v16,16(%r2)		/* Next part of haystack.  */

	vstrs	%v20,%v16,%v18,%v19,0,0

	jne	.Lloop_vstrs_nonzero_cc16

	vl	%v16,32(%r2)		/* Next part of haystack.  */

	vstrs	%v20,%v16,%v18,%v19,0,0

	jne	.Lloop_vstrs_nonzero_cc32

	vl	%v16,48(%r2)		/* Next part of haystack.  */

	la	%r2,64(%r2)

	vstrs	%v20,%v16,%v18,%v19,0,0

	jne	.Lloop_vstrs_nonzero_cc

	clgrjh	%r2,%r4,.Lhaystack_too_small

	vl	%v16,0(%r2)		/* Next part of haystack.  */

	clgrjle	%r2,%r0,.Lloop64

	j	.Lloop

END(MEMMEM_ARCH13)

# if ! HAVE_MEMMEM_IFUNC

strong_alias (MEMMEM_ARCH13, __memmem)

weak_alias (__memmem, memmem)

# endif

# if MEMMEM_Z13_ONLY_USED_AS_FALLBACK && defined SHARED && IS_IN (libc)

weak_alias (MEMMEM_ARCH13, __GI_memmem)

strong_alias (MEMMEM_ARCH13, __GI___memmem)

# endif

#endif