projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| 0c719f13 | 1 | /*- |
| 1ddae302 KB |
2 | * Copyright (c) 1991, 1993 |
| 3 | * The Regents of the University of California. All rights reserved. | |
| 0c719f13 KB |
4 | * |
| 5 | * This code is derived from software contributed to Berkeley by | |
| 6 | * Ralph Campbell. | |
| 7 | * | |
| 8 | * %sccs.include.redist.c% | |
| 9 | */ | |
| 10 | ||
| ad4c803f | 11 | #include <machine/machAsmDefs.h> |
| 3e6938a3 | 12 | |
| 0c719f13 | 13 | #if defined(LIBC_SCCS) && !defined(lint) |
| 1ddae302 | 14 | ASMSTR("@(#)ffs.s 8.1 (Berkeley) %G%") |
| 0c719f13 KB |
15 | #endif /* LIBC_SCCS and not lint */ |
| 16 | ||
| 0c719f13 KB |
17 | /* bit = ffs(value) */ |
| 18 | ||
| 19 | LEAF(ffs) | |
| 20 | move v0, zero | |
| 21 | beq a0, zero, done | |
| 22 | 1: | |
| 23 | and v1, a0, 1 # bit set? | |
| 24 | addu v0, v0, 1 | |
| 25 | srl a0, a0, 1 | |
| 26 | beq v1, zero, 1b # no, continue | |
| 27 | done: | |
| 28 | j ra | |
| 29 | END(ffs) |