projects / thirdparty / glibc.git / blame
| Commit | Line | Data |
|---|---|---|
| a92599ea | 1 | /* Compute the hypothenuse of X and Y. |
| 2b778ceb | 2 | Copyright (C) 1998-2021 Free Software Foundation, Inc. |
| a92599ea 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. | |
| a92599ea 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. |
| a92599ea | 15 | |
| 41bdb6e2 | 16 | You should have received a copy of the GNU Lesser General Public |
| 59ba27a6 | 17 | License along with the GNU C Library; if not, see |
| 5a82c748 | 18 | <https://www.gnu.org/licenses/>. */ |
| a92599ea UD |
19 | |
| 20 | #include <sysdep.h> | |
| 6f0f237b | 21 | #include <i386-math-asm.h> |
| 220622dd | 22 | #include <libm-alias-finite.h> |
| a92599ea | 23 | |
| f6987f5a JM |
24 | DEFINE_DBL_MIN |
| 25 | ||
| 26 | #ifdef PIC | |
| 27 | # define MO(op) op##@GOTOFF(%edx) | |
| 28 | #else | |
| 29 | # define MO(op) op | |
| 30 | #endif | |
| 31 | ||
| a92599ea UD |
32 | .text |
| 33 | ENTRY(__ieee754_hypot) | |
| f6987f5a JM |
34 | #ifdef PIC |
| 35 | LOAD_PIC_REG (dx) | |
| 36 | #endif | |
| a92599ea UD |
37 | fldl 4(%esp) // x |
| 38 | fxam | |
| 39 | fnstsw | |
| 40 | fldl 12(%esp) // y : x | |
| 41 | movb %ah, %ch | |
| 42 | fxam | |
| 43 | fnstsw | |
| 44 | movb %ah, %al | |
| 45 | orb %ch, %ah | |
| 46 | sahf | |
| 47 | jc 1f | |
| 48 | fmul %st(0) // y * y : x | |
| 49 | fxch // x : y * y | |
| 50 | fmul %st(0) // x * x : y * y | |
| 51 | faddp // x * x + y * y | |
| 52 | fsqrt | |
| f6987f5a | 53 | DBL_NARROW_EVAL_UFLOW_NONNEG |
| a92599ea UD |
54 | 2: ret |
| 55 | ||
| 56 | // We have to test whether any of the parameters is Inf. | |
| 57 | // In this case the result is infinity. | |
| 58 | 1: andb $0x45, %al | |
| 59 | cmpb $5, %al | |
| 60 | je 3f // jump if y is Inf | |
| 61 | andb $0x45, %ch | |
| 62 | cmpb $5, %ch | |
| 63 | jne 4f // jump if x is not Inf | |
| 64 | fxch | |
| 65 | 3: fstp %st(1) | |
| 66 | fabs | |
| 67 | jmp 2b | |
| 68 | ||
| 69 | 4: testb $1, %al | |
| 70 | jnz 5f // y is NaN | |
| 71 | fxch | |
| 72 | 5: fstp %st(1) | |
| 73 | jmp 2b | |
| 0ac5ae23 | 74 | |
| a92599ea | 75 | END(__ieee754_hypot) |
| 220622dd | 76 | libm_alias_finite (__ieee754_hypot, __hypot) |