| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* strlen_user.S: Sparc optimized strlen_user code |
| 2 | * |
| 3 | * Return length of string in userspace including terminating 0 |
| 4 | * or 0 for error |
| 5 | * |
| 6 | * Copyright (C) 1991,1996 Free Software Foundation |
| 7 | * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu) |
| 8 | * Copyright (C) 1996 Jakub Jelinek (jj@sunsite.mff.cuni.cz) |
| 9 | */ |
| 10 | |
| 11 | #define LO_MAGIC 0x01010101 |
| 12 | #define HI_MAGIC 0x80808080 |
| 13 | |
| 14 | 10: |
| 15 | ldub [%o0], %o5 |
| 16 | cmp %o5, 0 |
| 17 | be 1f |
| 18 | add %o0, 1, %o0 |
| 19 | andcc %o0, 3, %g0 |
| 20 | be 4f |
| 21 | or %o4, %lo(HI_MAGIC), %o3 |
| 22 | 11: |
| 23 | ldub [%o0], %o5 |
| 24 | cmp %o5, 0 |
| 25 | be 2f |
| 26 | add %o0, 1, %o0 |
| 27 | andcc %o0, 3, %g0 |
| 28 | be 5f |
| 29 | sethi %hi(LO_MAGIC), %o4 |
| 30 | 12: |
| 31 | ldub [%o0], %o5 |
| 32 | cmp %o5, 0 |
| 33 | be 3f |
| 34 | add %o0, 1, %o0 |
| 35 | b 13f |
| 36 | or %o4, %lo(LO_MAGIC), %o2 |
| 37 | 1: |
| 38 | retl |
| 39 | mov 1, %o0 |
| 40 | 2: |
| 41 | retl |
| 42 | mov 2, %o0 |
| 43 | 3: |
| 44 | retl |
| 45 | mov 3, %o0 |
| 46 | |
| 47 | .align 4 |
| 48 | .global __strlen_user, __strnlen_user |
| 49 | __strlen_user: |
| 50 | sethi %hi(32768), %o1 |
| 51 | __strnlen_user: |
| 52 | mov %o1, %g1 |
| 53 | mov %o0, %o1 |
| 54 | andcc %o0, 3, %g0 |
| 55 | bne 10b |
| 56 | sethi %hi(HI_MAGIC), %o4 |
| 57 | or %o4, %lo(HI_MAGIC), %o3 |
| 58 | 4: |
| 59 | sethi %hi(LO_MAGIC), %o4 |
| 60 | 5: |
| 61 | or %o4, %lo(LO_MAGIC), %o2 |
| 62 | 13: |
| 63 | ld [%o0], %o5 |
| 64 | 2: |
| 65 | sub %o5, %o2, %o4 |
| 66 | andcc %o4, %o3, %g0 |
| 67 | bne 82f |
| 68 | add %o0, 4, %o0 |
| 69 | sub %o0, %o1, %g2 |
| 70 | 81: cmp %g2, %g1 |
| 71 | blu 13b |
| 72 | mov %o0, %o4 |
| 73 | ba,a 1f |
| 74 | |
| 75 | /* Check every byte. */ |
| 76 | 82: srl %o5, 24, %g5 |
| 77 | andcc %g5, 0xff, %g0 |
| 78 | be 1f |
| 79 | add %o0, -3, %o4 |
| 80 | srl %o5, 16, %g5 |
| 81 | andcc %g5, 0xff, %g0 |
| 82 | be 1f |
| 83 | add %o4, 1, %o4 |
| 84 | srl %o5, 8, %g5 |
| 85 | andcc %g5, 0xff, %g0 |
| 86 | be 1f |
| 87 | add %o4, 1, %o4 |
| 88 | andcc %o5, 0xff, %g0 |
| 89 | bne 81b |
| 90 | sub %o0, %o1, %g2 |
| 91 | |
| 92 | add %o4, 1, %o4 |
| 93 | 1: |
| 94 | retl |
| 95 | sub %o4, %o1, %o0 |
| 96 | |
| 97 | .section .fixup,#alloc,#execinstr |
| 98 | .align 4 |
| 99 | 9: |
| 100 | retl |
| 101 | clr %o0 |
| 102 | |
| 103 | .section __ex_table,#alloc |
| 104 | .align 4 |
| 105 | |
| 106 | .word 10b, 9b |
| 107 | .word 11b, 9b |
| 108 | .word 12b, 9b |
| 109 | .word 13b, 9b |