2 * strncpy_from_user.S: Sparc64 strncpy from userspace.
4 * Copyright (C) 1997, 1999 Jakub Jelinek (jj@ultra.linux.cz)
7 #include <linux/linkage.h>
13 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 ENTRY(__strncpy_from_user)
34 /* %o0=dest, %o1=src, %o2=count */
35 andcc %o1, 7, %g0 ! IEU1 Group
36 bne,pn %icc, 30f ! CTI
37 add %o0, %o2, %g3 ! IEU0
38 60: ldxa [%o1] %asi, %g1 ! Load Group
39 brlez,pn %o2, 10f ! CTI
41 50: sethi %hi(0b), %o4 ! IEU0 Group
42 ldx [%o4 + %lo(0b)], %o4 ! Load
43 sllx %o4, 7, %o5 ! IEU1 Group
44 1: sub %g1, %o4, %g2 ! IEU0 Group
45 stx %g1, [%o0] ! Store
46 add %o0, 8, %o0 ! IEU1
47 andcc %g2, %o5, %g0 ! IEU1 Group
49 add %o1, 8, %o1 ! IEU0
50 cmp %o0, %g3 ! IEU1 Group
51 bl,a,pt %xcc, 1b ! CTI
52 61: ldxa [%o1] %asi, %g1 ! Load
55 5: srlx %g2, 32, %g7 ! IEU0 Group
56 sethi %hi(0xff00), %o4 ! IEU1
57 andcc %g7, %o5, %g0 ! IEU1 Group
59 or %o4, %lo(0xff00), %o4 ! IEU0
60 srlx %g1, 48, %g7 ! IEU0 Group
61 andcc %g7, %o4, %g0 ! IEU1 Group
63 andcc %g7, 0xff, %g0 ! IEU1 Group
65 srlx %g1, 32, %g7 ! IEU0
66 andcc %g7, %o4, %g0 ! IEU1 Group
68 andcc %g7, 0xff, %g0 ! IEU1 Group
70 2: andcc %g2, %o5, %g0 ! IEU1 Group
72 srl %g1, 16, %g7 ! IEU0
73 andcc %g7, %o4, %g0 ! IEU1 Group
75 andcc %g7, 0xff, %g0 ! IEU1 Group
77 andcc %g1, %o4, %g0 ! IEU1 Group
79 andcc %g1, 0xff, %g0 ! IEU1 Group
80 be,a,pn %icc, 57f ! CTI
81 sub %o0, %o3, %o0 ! IEU0
82 2: cmp %o0, %g3 ! IEU1 Group
83 bl,a,pt %xcc, 50b ! CTI
84 62: ldxa [%o1] %asi, %g1 ! Load
102 55: sub %o0, %o3, %o0
105 56: sub %o0, %o3, %o0
113 63: lduba [%o1] %asi, %o4
119 64: lduba [%o1] %asi, %o4
124 ENDPROC(__strncpy_from_user)
126 .section __ex_table,"a"
128 .word 60b, __retl_efault
129 .word 61b, __retl_efault
130 .word 62b, __retl_efault
131 .word 63b, __retl_efault
132 .word 64b, __retl_efault