1 /* $Id: strncpy_from_user.S,v 1.6 1999/05/25 16:53:05 jj Exp $
2 * strncpy_from_user.S: Sparc64 strncpy from userspace.
4 * Copyright (C) 1997, 1999 Jakub Jelinek (jj@ultra.linux.cz)
12 0: .xword 0x0101010101010101
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)
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)
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.
33 .globl __strncpy_from_user
35 /* %o0=dest, %o1=src, %o2=count */
36 sethi %hi(0b), %o5 ! IEU0 Group
37 andcc %o1, 7, %g0 ! IEU1
38 bne,pn %icc, 30f ! CTI
39 ldx [%o5 + %lo(0b)], %o4 ! Load Group
40 add %o0, %o2, %g3 ! IEU0
41 60: ldxa [%o1] %asi, %g1 ! Load Group
42 brlez,pn %o2, 10f ! CTI
43 sllx %o4, 7, %o5 ! IEU0 Group
45 1: sub %g1, %o4, %g2 ! IEU0 Group
46 stx %g1, [%o0] ! Store
47 add %o0, 8, %o0 ! IEU1
48 andcc %g2, %o5, %g0 ! IEU1 Group
50 add %o1, 8, %o1 ! IEU0
51 cmp %o0, %g3 ! IEU1 Group
52 bl,a,pt %xcc, 1b ! CTI
53 61: ldxa [%o1] %asi, %g1 ! Load
56 5: srlx %g2, 32, %g7 ! IEU0 Group
57 sethi %hi(0xff00), %g5 ! IEU1
58 andcc %g7, %o5, %g0 ! IEU1 Group
60 or %g5, %lo(0xff00), %g5 ! IEU0
61 srlx %g1, 48, %g7 ! IEU0 Group
62 andcc %g7, %g5, %g0 ! IEU1 Group
64 andcc %g7, 0xff, %g0 ! IEU1 Group
66 srlx %g1, 32, %g7 ! IEU0
67 andcc %g7, %g5, %g0 ! IEU1 Group
69 andcc %g7, 0xff, %g0 ! IEU1 Group
71 2: andcc %g2, %o5, %g0 ! IEU1 Group
73 srl %g1, 16, %g7 ! IEU0
74 andcc %g7, %g5, %g0 ! IEU1 Group
76 andcc %g7, 0xff, %g0 ! IEU1 Group
78 andcc %g1, %g5, %g0 ! IEU1 Group
80 andcc %g1, 0xff, %g0 ! IEU1 Group
81 be,a,pn %icc, 57f ! CTI
82 sub %o0, %o3, %o0 ! IEU0
83 2: cmp %o0, %g3 ! IEU1 Group
84 bl,a,pt %xcc, 1b ! CTI
85 62: ldxa [%o1] %asi, %g1 ! Load
100 54: sub %o0, %o3, %o0
103 55: sub %o0, %o3, %o0
106 56: sub %o0, %o3, %o0
114 63: lduba [%o1] %asi, %o4
120 64: lduba [%o1] %asi, %o4
126 .section .fixup,#alloc,#execinstr
131 .section __ex_table,#alloc