1/* Copyright (C) 2000-2022 Free Software Foundation, Inc.
2   This file is part of the GNU C Library.
3
4   The GNU C Library is free software; you can redistribute it and/or
5   modify it under the terms of the GNU Lesser General Public
6   License as published by the Free Software Foundation; either
7   version 2.1 of the License, or (at your option) any later version.
8
9   The GNU C Library is distributed in the hope that it will be useful,
10   but WITHOUT ANY WARRANTY; without even the implied warranty of
11   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12   Lesser General Public License for more details.
13
14   You should have received a copy of the GNU Lesser General Public
15   License along with the GNU C Library.  If not, see
16   <https://www.gnu.org/licenses/>.  */
17
18/* Append no more than COUNT characters from the null-terminated string SRC
19   to the null-terminated string DST.  Always null-terminate the new DST.  */
20
21#include <sysdep.h>
22
23	.arch ev6
24	.set noreorder
25	.text
26
27ENTRY(strncat)
28	ldgp	gp, 0(pv)
29#ifdef PROF
30	.set noat
31	lda	AT, _mcount
32	jsr	AT, (AT), _mcount
33	.set at
34#endif
35	.prologue 1
36
37	mov	a0, v0		# set up return value
38	beq	a2, $zerocount	# U :
39	/* Find the end of the string.  */
40	ldq_u   t0, 0(a0)	# L : load first quadword (a0 may be misaligned)
41	lda     t1, -1		# E :
42
43	insqh   t1, v0, t1	# U :
44	andnot  a0, 7, a0	# E :
45	nop			# E :
46	or      t1, t0, t0	# E :
47
48	nop			# E :
49	nop			# E :
50	cmpbge  zero, t0, t1	# E : bits set iff byte == 0
51	bne     t1, $found	# U :
52
53$loop:	ldq     t0, 8(a0)	# L :
54	addq    a0, 8, a0	# E :
55	cmpbge  zero, t0, t1	# E :
56	beq     t1, $loop	# U :
57
58$found:	cttz	t1, t2		# U0 :
59	addq	a0, t2, a0	# E :
60	jsr	t9, __stxncpy	# L0 : Now do the append.
61
62	/* Worry about the null termination.  */
63
64	cttz	t10, t2		# U0: byte offset of end-of-count.
65	bic	a0, 7, a0	# E : word align the last write address.
66	zapnot	t0, t8, t1	# U : was last byte a null?
67	nop			# E :
68
69	bne	t1, 0f		# U :
70	nop			# E :
71	nop			# E :
72	ret			# L0 :
73
740:	addq	t2, a0, a0	# E : address of end-of-count
75	stb	zero, 1(a0)	# L :
76	nop			# E :
77	ret			# L0 :
78
79$zerocount:
80	nop			# E :
81	nop			# E :
82	nop			# E :
83	ret			# L0 :
84
85	END(strncat)
86