projects / thirdparty / glibc.git / blame
| Commit | Line | Data |
|---|---|---|
| 85f72e9c | 1 | /* Compute hash alue for given string according to ELF standard. |
| bfff8b1b | 2 | Copyright (C) 1998-2017 Free Software Foundation, Inc. |
| 85f72e9c UD |
3 | This file is part of the GNU C Library. |
| 4 | Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998. | |
| 5 | ||
| 6 | The GNU C Library is free software; you can redistribute it and/or | |
| 41bdb6e2 AJ |
7 | modify it under the terms of the GNU Lesser General Public |
| 8 | License as published by the Free Software Foundation; either | |
| 9 | version 2.1 of the License, or (at your option) any later version. | |
| 85f72e9c UD |
10 | |
| 11 | The GNU C Library is distributed in the hope that it will be useful, | |
| 12 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 41bdb6e2 | 14 | Lesser General Public License for more details. |
| 85f72e9c | 15 | |
| 41bdb6e2 | 16 | You should have received a copy of the GNU Lesser General Public |
| 59ba27a6 PE |
17 | License along with the GNU C Library; if not, see |
| 18 | <http://www.gnu.org/licenses/>. */ | |
| 85f72e9c UD |
19 | |
| 20 | #ifndef _DL_HASH_H | |
| 21 | #define _DL_HASH_H 1 | |
| 22 | ||
| 23 | ||
| 24 | /* This is the hashing function specified by the ELF ABI. It is highly | |
| 25 | optimized for the PII processors. Though it will run on i586 it | |
| 26 | would be much slower than the generic C implementation. So don't | |
| 27 | use it. */ | |
| 50441a98 | 28 | static unsigned int |
| b4f518ec | 29 | __attribute__ ((unused)) |
| 9cfe5381 | 30 | _dl_elf_hash (const char *name) |
| 85f72e9c UD |
31 | { |
| 32 | unsigned int result; | |
| 33 | unsigned int temp0; | |
| 34 | unsigned int temp1; | |
| 35 | ||
| 36 | __asm__ __volatile__ | |
| 37 | ("movzbl (%1),%2\n\t" | |
| 38 | "testl %2, %2\n\t" | |
| 39 | "jz 1f\n\t" | |
| 40 | "movl %2, %0\n\t" | |
| 41 | "movzbl 1(%1), %2\n\t" | |
| 42 | "jecxz 1f\n\t" | |
| 43 | "shll $4, %0\n\t" | |
| 44 | "addl %2, %0\n\t" | |
| 45 | "movzbl 2(%1), %2\n\t" | |
| 46 | "jecxz 1f\n\t" | |
| 47 | "shll $4, %0\n\t" | |
| 48 | "addl %2, %0\n\t" | |
| 49 | "movzbl 3(%1), %2\n\t" | |
| 50 | "jecxz 1f\n\t" | |
| 51 | "shll $4, %0\n\t" | |
| 52 | "addl %2, %0\n\t" | |
| 53 | "movzbl 4(%1), %2\n\t" | |
| 54 | "jecxz 1f\n\t" | |
| 55 | "shll $4, %0\n\t" | |
| 56 | "addl $5, %1\n\t" | |
| 57 | "addl %2, %0\n\t" | |
| 58 | "movzbl (%1), %2\n\t" | |
| 59 | "jecxz 1f\n" | |
| 60 | "2:\t" | |
| 61 | "shll $4, %0\n\t" | |
| 62 | "movl $0xf0000000, %3\n\t" | |
| 63 | "incl %1\n\t" | |
| 64 | "addl %2, %0\n\t" | |
| 65 | "andl %0, %3\n\t" | |
| 66 | "andl $0x0fffffff, %0\n\t" | |
| 67 | "shrl $24, %3\n\t" | |
| 68 | "movzbl (%1), %2\n\t" | |
| 69 | "xorl %3, %0\n\t" | |
| 70 | "testl %2, %2\n\t" | |
| 71 | "jnz 2b\n" | |
| 72 | "1:\t" | |
| 73 | : "=&r" (result), "=r" (name), "=&c" (temp0), "=&r" (temp1) | |
| 9cfe5381 | 74 | : "0" (0), "1" ((const unsigned char *) name)); |
| 85f72e9c UD |
75 | |
| 76 | return result; | |
| 77 | } | |
| 78 | ||
| 79 | #endif /* dl-hash.h */ |