projects / thirdparty / glibc.git / blame
| Commit | Line | Data |
|---|---|---|
| 26dee9c4 | 1 | /* ix87 specific frexp implementation for double. |
| 04277e02 | 2 | Copyright (C) 1997-2019 Free Software Foundation, Inc. |
| 26dee9c4 UD |
3 | This file is part of the GNU C Library. |
| 4 | Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997. | |
| 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. | |
| 26dee9c4 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. |
| 26dee9c4 | 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/>. */ | |
| 26dee9c4 UD |
19 | |
| 20 | #include <machine/asm.h> | |
| bc4e8f9b | 21 | #include <libm-alias-double.h> |
| 26dee9c4 | 22 | |
| 26dee9c4 | 23 | .section .rodata |
| 26dee9c4 UD |
24 | |
| 25 | .align ALIGNARG(4) | |
| b67e9372 | 26 | .type two54,@object |
| 26dee9c4 UD |
27 | two54: .byte 0, 0, 0, 0, 0, 0, 0x50, 0x43 |
| 28 | ASM_SIZE_DIRECTIVE(two54) | |
| 29 | ||
| 30 | #ifdef PIC | |
| 31 | #define MO(op) op##@GOTOFF(%edx) | |
| 32 | #else | |
| 33 | #define MO(op) op | |
| 34 | #endif | |
| 35 | ||
| 2366713d | 36 | #define PARMS 4 /* no space for saved regs */ |
| 9e25f6e2 GM |
37 | #define VAL0 PARMS |
| 38 | #define VAL1 VAL0+4 | |
| 39 | #define EXPP VAL1+4 | |
| 40 | ||
| 26dee9c4 | 41 | .text |
| 2366713d | 42 | ENTRY (__frexp) |
| 9e25f6e2 GM |
43 | |
| 44 | movl VAL0(%esp), %ecx | |
| 45 | movl VAL1(%esp), %eax | |
| 26dee9c4 UD |
46 | movl %eax, %edx |
| 47 | andl $0x7fffffff, %eax | |
| 48 | orl %eax, %ecx | |
| 49 | jz 1f | |
| 50 | xorl %ecx, %ecx | |
| 51 | cmpl $0x7ff00000, %eax | |
| 52 | jae 1f | |
| 53 | ||
| 54 | cmpl $0x00100000, %eax | |
| 55 | jae 2f | |
| 56 | ||
| 9e25f6e2 | 57 | fldl VAL0(%esp) |
| 26dee9c4 | 58 | #ifdef PIC |
| fee732e5 | 59 | LOAD_PIC_REG (dx) |
| 26dee9c4 UD |
60 | #endif |
| 61 | fmull MO(two54) | |
| 62 | movl $-54, %ecx | |
| 9e25f6e2 | 63 | fstpl VAL0(%esp) |
| 00f5fcbb | 64 | fwait |
| 9e25f6e2 | 65 | movl VAL1(%esp), %eax |
| 26dee9c4 UD |
66 | movl %eax, %edx |
| 67 | andl $0x7fffffff, %eax | |
| 68 | ||
| 69 | 2: shrl $20, %eax | |
| 70 | andl $0x800fffff, %edx | |
| 71 | subl $1022, %eax | |
| 72 | orl $0x3fe00000, %edx | |
| 73 | addl %eax, %ecx | |
| 9e25f6e2 | 74 | movl %edx, VAL1(%esp) |
| 26dee9c4 UD |
75 | |
| 76 | /* Store %ecx in the variable pointed to by the second argument, | |
| 77 | get the factor from the stack and return. */ | |
| 9e25f6e2 | 78 | 1: movl EXPP(%esp), %eax |
| 9e25f6e2 | 79 | fldl VAL0(%esp) |
| 26dee9c4 | 80 | movl %ecx, (%eax) |
| 9e25f6e2 | 81 | |
| 26dee9c4 | 82 | ret |
| 2366713d | 83 | END (__frexp) |
| bc4e8f9b | 84 | libm_alias_double (__frexp, frexp) |