projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| a0c6fdb9 NP |
1 | /* |
| 2 | * linux/arch/arm/lib/clear_user.S | |
| 3 | * | |
| 4 | * Copyright (C) 1995, 1996,1997,1998 Russell King | |
| 5 | * | |
| 6 | * This program is free software; you can redistribute it and/or modify | |
| 7 | * it under the terms of the GNU General Public License version 2 as | |
| 8 | * published by the Free Software Foundation. | |
| 9 | */ | |
| 10 | #include <linux/linkage.h> | |
| 11 | #include <asm/assembler.h> | |
| 12 | ||
| 13 | .text | |
| 14 | ||
| 15 | /* Prototype: int __arch_clear_user(void *addr, size_t sz) | |
| 16 | * Purpose : clear some user memory | |
| 17 | * Params : addr - user memory address to clear | |
| 18 | * : sz - number of bytes to clear | |
| 19 | * Returns : number of bytes NOT cleared | |
| 20 | */ | |
| 21 | ENTRY(__arch_clear_user) | |
| 22 | stmfd sp!, {r1, lr} | |
| 23 | mov r2, #0 | |
| 24 | cmp r1, #4 | |
| 25 | blt 2f | |
| 26 | ands ip, r0, #3 | |
| 27 | beq 1f | |
| 28 | cmp ip, #2 | |
| 29 | USER( strbt r2, [r0], #1) | |
| 30 | USER( strlebt r2, [r0], #1) | |
| 31 | USER( strltbt r2, [r0], #1) | |
| 32 | rsb ip, ip, #4 | |
| 33 | sub r1, r1, ip @ 7 6 5 4 3 2 1 | |
| 34 | 1: subs r1, r1, #8 @ -1 -2 -3 -4 -5 -6 -7 | |
| 35 | USER( strplt r2, [r0], #4) | |
| 36 | USER( strplt r2, [r0], #4) | |
| 37 | bpl 1b | |
| 38 | adds r1, r1, #4 @ 3 2 1 0 -1 -2 -3 | |
| 39 | USER( strplt r2, [r0], #4) | |
| 40 | 2: tst r1, #2 @ 1x 1x 0x 0x 1x 1x 0x | |
| 41 | USER( strnebt r2, [r0], #1) | |
| 42 | USER( strnebt r2, [r0], #1) | |
| 43 | tst r1, #1 @ x1 x0 x1 x0 x1 x0 x1 | |
| 44 | USER( strnebt r2, [r0], #1) | |
| 45 | mov r0, #0 | |
| 46 | LOADREGS(fd,sp!, {r1, pc}) | |
| 47 | ||
| 48 | .section .fixup,"ax" | |
| 49 | .align 0 | |
| 50 | 9001: LOADREGS(fd,sp!, {r0, pc}) | |
| 51 | .previous | |
| 52 |