lh | 9ed821d | 2023-04-07 01:36:19 -0700 | [diff] [blame^] | 1 | /* Copyright (C) 1998 Free Software Foundation, Inc. |
| 2 | This file is part of the GNU C Library. |
| 3 | Contributed by Philip Blundell <philb@gnu.org> |
| 4 | |
| 5 | The GNU C Library is free software; you can redistribute it and/or |
| 6 | modify it under the terms of the GNU Lesser General Public |
| 7 | License as published by the Free Software Foundation; either |
| 8 | version 2.1 of the License, or (at your option) any later version. |
| 9 | |
| 10 | The GNU C Library is distributed in the hope that it will be useful, |
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 13 | Lesser General Public License for more details. |
| 14 | |
| 15 | You should have received a copy of the GNU Lesser General Public |
| 16 | License along with the GNU C Library; if not, write to the Free |
| 17 | Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 18 | 02111-1307 USA. */ |
| 19 | |
| 20 | #include <features.h> |
| 21 | #include <sys/syscall.h> |
| 22 | #include <bits/arm_asm.h> |
| 23 | |
| 24 | .text |
| 25 | .global memset |
| 26 | .type memset,%function |
| 27 | .align 4 |
| 28 | |
| 29 | #if defined(THUMB1_ONLY) |
| 30 | .thumb_func |
| 31 | memset: |
| 32 | mov ip, r0 |
| 33 | cmp r2, #8 @ at least 8 bytes to do? |
| 34 | bcc 2f |
| 35 | |
| 36 | lsl r3, r1, #8 |
| 37 | orr r1, r3 |
| 38 | lsl r3, r1, #16 |
| 39 | orr r1, r3 |
| 40 | |
| 41 | mov r3, #3 |
| 42 | 1: @ Fill up to the first word boundary |
| 43 | tst r0, r3 |
| 44 | beq 1f |
| 45 | strb r1, [r0] |
| 46 | add r0, r0, #1 |
| 47 | sub r2, r2, #1 |
| 48 | b 1b |
| 49 | 1: @ Fill aligned words |
| 50 | str r1, [r0] |
| 51 | add r0, r0, #4 |
| 52 | sub r2, r2, #4 |
| 53 | cmp r2, #4 |
| 54 | bcs 1b |
| 55 | |
| 56 | 2: @ Fill the remaining bytes |
| 57 | cmp r2, #0 |
| 58 | beq 2f |
| 59 | 1: |
| 60 | strb r1, [r0] |
| 61 | add r0, r0, #1 |
| 62 | sub r2, r2, #1 |
| 63 | bne 1b |
| 64 | 2: |
| 65 | mov r0, ip |
| 66 | bx lr |
| 67 | #else |
| 68 | memset: |
| 69 | mov a4, a1 |
| 70 | cmp a3, $8 @ at least 8 bytes to do? |
| 71 | blt 2f |
| 72 | orr a2, a2, a2, lsl $8 |
| 73 | orr a2, a2, a2, lsl $16 |
| 74 | 1: |
| 75 | tst a4, $3 @ aligned yet? |
| 76 | #if defined(__thumb2__) |
| 77 | itt ne |
| 78 | strbne a2, [a4], $1 |
| 79 | subne a3, a3, $1 |
| 80 | #else |
| 81 | strneb a2, [a4], $1 |
| 82 | subne a3, a3, $1 |
| 83 | #endif |
| 84 | bne 1b |
| 85 | mov ip, a2 |
| 86 | 1: |
| 87 | cmp a3, $8 @ 8 bytes still to do? |
| 88 | blt 2f |
| 89 | stmia a4!, {a2, ip} |
| 90 | sub a3, a3, $8 |
| 91 | cmp a3, $8 @ 8 bytes still to do? |
| 92 | blt 2f |
| 93 | stmia a4!, {a2, ip} |
| 94 | sub a3, a3, $8 |
| 95 | cmp a3, $8 @ 8 bytes still to do? |
| 96 | blt 2f |
| 97 | stmia a4!, {a2, ip} |
| 98 | sub a3, a3, $8 |
| 99 | cmp a3, $8 @ 8 bytes still to do? |
| 100 | #if defined(__thumb2__) |
| 101 | itt ge |
| 102 | stmiage a4!, {a2, ip} |
| 103 | subge a3, a3, $8 |
| 104 | #else |
| 105 | stmgeia a4!, {a2, ip} |
| 106 | subge a3, a3, $8 |
| 107 | #endif |
| 108 | bge 1b |
| 109 | 2: |
| 110 | movs a3, a3 @ anything left? |
| 111 | IT(t, eq) |
| 112 | #if defined(__USE_BX__) |
| 113 | bxeq lr |
| 114 | #else |
| 115 | moveq pc, lr @ nope |
| 116 | #endif |
| 117 | #if defined (__thumb2__) |
| 118 | 1: |
| 119 | strb a2, [a4], #1 |
| 120 | subs a3, a3, #1 |
| 121 | bne 1b |
| 122 | bx lr |
| 123 | #else |
| 124 | rsb a3, a3, $7 |
| 125 | add pc, pc, a3, lsl $2 |
| 126 | mov r0, r0 |
| 127 | strb a2, [a4], $1 |
| 128 | strb a2, [a4], $1 |
| 129 | strb a2, [a4], $1 |
| 130 | strb a2, [a4], $1 |
| 131 | strb a2, [a4], $1 |
| 132 | strb a2, [a4], $1 |
| 133 | strb a2, [a4], $1 |
| 134 | #if defined(__USE_BX__) |
| 135 | bx lr |
| 136 | #else |
| 137 | mov pc, lr |
| 138 | #endif |
| 139 | #endif |
| 140 | #endif |
| 141 | |
| 142 | .size memset,.-memset |
| 143 | |
| 144 | libc_hidden_def(memset) |