1/*
  2 * strncpy_from_user.S: Sparc64 strncpy from userspace.
  3 *
  4 *  Copyright (C) 1997, 1999 Jakub Jelinek (jj@ultra.linux.cz)
  5 */
  6
  7#include <asm/asi.h>
  8#include <asm/errno.h>
  9
 10	.data
 11	.align	8
 120:	.xword	0x0101010101010101
 13
 14	.text
 15	.align	32
 16
 17	/* Must return:
 18	 *
 19	 * -EFAULT		for an exception
 20	 * count		if we hit the buffer limit
 21	 * bytes copied		if we hit a null byte
 22	 * (without the null byte)
 23	 *
 24	 * This implementation assumes:
 25	 * %o1 is 8 aligned => !(%o2 & 7)
 26	 * %o0 is 8 aligned (if not, it will be slooooow, but will work)
 27	 *
 28	 * This is optimized for the common case:
 29	 * in my stats, 90% of src are 8 aligned (even on sparc32)
 30	 * and average length is 18 or so.
 31	 */
 32
 33	.globl	__strncpy_from_user
 34	.type	__strncpy_from_user,#function
 35__strncpy_from_user:
 36	/* %o0=dest, %o1=src, %o2=count */
 37	andcc	%o1, 7, %g0		! IEU1	Group
 38	bne,pn	%icc, 30f		! CTI
 39	 add	%o0, %o2, %g3		! IEU0
 4060:	ldxa	[%o1] %asi, %g1		! Load	Group
 41	brlez,pn %o2, 10f		! CTI
 42	 mov	%o0, %o3		! IEU0
 4350:	sethi	%hi(0b), %o4		! IEU0	Group
 44	ldx	[%o4 + %lo(0b)], %o4	! Load
 45	sllx	%o4, 7, %o5		! IEU1	Group
 461:	sub	%g1, %o4, %g2		! IEU0	Group
 47	stx	%g1, [%o0]		! Store
 48	add	%o0, 8, %o0		! IEU1
 49	andcc	%g2, %o5, %g0		! IEU1	Group
 50	bne,pn	%xcc, 5f		! CTI
 51	 add	%o1, 8, %o1		! IEU0
 52	cmp	%o0, %g3		! IEU1	Group
 53	bl,a,pt %xcc, 1b		! CTI
 5461:	 ldxa	[%o1] %asi, %g1		! Load
 5510:	retl				! CTI	Group
 56	 mov	%o2, %o0		! IEU0
 575:	srlx	%g2, 32, %g7		! IEU0	Group
 58	sethi	%hi(0xff00), %o4	! IEU1
 59	andcc	%g7, %o5, %g0		! IEU1	Group
 60	be,pn	%icc, 2f		! CTI
 61	 or	%o4, %lo(0xff00), %o4	! IEU0
 62	srlx	%g1, 48, %g7		! IEU0	Group
 63	andcc	%g7, %o4, %g0		! IEU1	Group
 64	be,pn	%icc, 50f		! CTI
 65	 andcc	%g7, 0xff, %g0		! IEU1	Group
 66	be,pn	%icc, 51f		! CTI
 67	 srlx	%g1, 32, %g7		! IEU0
 68	andcc	%g7, %o4, %g0		! IEU1	Group
 69	be,pn	%icc, 52f		! CTI
 70	 andcc	%g7, 0xff, %g0		! IEU1	Group
 71	be,pn	%icc, 53f		! CTI
 722:	 andcc	%g2, %o5, %g0		! IEU1	Group
 73	be,pn	%icc, 2f		! CTI
 74	 srl	%g1, 16, %g7		! IEU0
 75	andcc	%g7, %o4, %g0		! IEU1	Group
 76	be,pn	%icc, 54f		! CTI
 77	 andcc	%g7, 0xff, %g0		! IEU1	Group
 78	be,pn	%icc, 55f		! CTI
 79	 andcc	%g1, %o4, %g0		! IEU1	Group
 80	be,pn	%icc, 56f		! CTI
 81	 andcc	%g1, 0xff, %g0		! IEU1	Group
 82	be,a,pn	%icc, 57f		! CTI
 83	 sub	%o0, %o3, %o0		! IEU0
 842:	cmp	%o0, %g3		! IEU1	Group
 85	bl,a,pt	%xcc, 50b		! CTI
 8662:	 ldxa	[%o1] %asi, %g1		! Load
 87	retl				! CTI	Group
 88	 mov	%o2, %o0		! IEU0
 8950:	sub	%o0, %o3, %o0
 90	retl
 91	 sub	%o0, 8, %o0
 9251:	sub	%o0, %o3, %o0
 93	retl
 94	 sub	%o0, 7, %o0
 9552:	sub	%o0, %o3, %o0
 96	retl
 97	 sub	%o0, 6, %o0
 9853:	sub	%o0, %o3, %o0
 99	retl
100	 sub	%o0, 5, %o0
10154:	sub	%o0, %o3, %o0
102	retl
103	 sub	%o0, 4, %o0
10455:	sub	%o0, %o3, %o0
105	retl
106	 sub	%o0, 3, %o0
10756:	sub	%o0, %o3, %o0
108	retl
109	 sub	%o0, 2, %o0
11057:	retl
111	 sub	%o0, 1, %o0
11230:	brlez,pn %o2, 3f
113	 sub	%g0, %o2, %o3
114	add	%o0, %o2, %o0
11563:	lduba	[%o1] %asi, %o4
1161:	add	%o1, 1, %o1
117	brz,pn	%o4, 2f
118	 stb	%o4, [%o0 + %o3]
119	addcc	%o3, 1, %o3
120	bne,pt	%xcc, 1b
12164:	 lduba	[%o1] %asi, %o4
1223:	retl
123	 mov	%o2, %o0
1242:	retl
125	 add	%o2, %o3, %o0
126	.size	__strncpy_from_user, .-__strncpy_from_user
127
128	.section __ex_table,"a"
129	.align	4
130	.word	60b, __retl_efault
131	.word	61b, __retl_efault
132	.word	62b, __retl_efault
133	.word	63b, __retl_efault
134	.word	64b, __retl_efault
135	.previous