mirror of
https://github.com/KolibriOS/kolibrios.git
synced 2024-12-24 23:56:49 +03:00
41 lines
723 B
C
41 lines
723 B
C
|
/*
|
||
|
|
* Written by J.T. Conklin <jtc@netbsd.org>.
|
||
|
|
* Public domain.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include <math.h>
|
||
|
|
|
||
|
|
float
|
||
|
|
acosf (float x)
|
||
|
|
{
|
||
|
|
float res;
|
||
|
|
|
||
|
|
/* acosl = atanl (sqrtl(1 - x^2) / x) */
|
||
|
|
asm ( "fld %%st\n\t"
|
||
|
|
"fmul %%st(0)\n\t" /* x^2 */
|
||
|
|
"fld1\n\t"
|
||
|
|
"fsubp\n\t" /* 1 - x^2 */
|
||
|
|
"fsqrt\n\t" /* sqrtl (1 - x^2) */
|
||
|
|
"fxch %%st(1)\n\t"
|
||
|
|
"fpatan"
|
||
|
|
: "=t" (res) : "0" (x) : "st(1)");
|
||
|
|
return res;
|
||
|
|
}
|
||
|
|
|
||
|
|
double
|
||
|
|
acos (double x)
|
||
|
|
{
|
||
|
|
double res;
|
||
|
|
|
||
|
|
/* acosl = atanl (sqrtl(1 - x^2) / x) */
|
||
|
|
asm ( "fld %%st\n\t"
|
||
|
|
"fmul %%st(0)\n\t" /* x^2 */
|
||
|
|
"fld1\n\t"
|
||
|
|
"fsubp\n\t" /* 1 - x^2 */
|
||
|
|
"fsqrt\n\t" /* sqrtl (1 - x^2) */
|
||
|
|
"fxch %%st(1)\n\t"
|
||
|
|
"fpatan"
|
||
|
|
: "=t" (res) : "0" (x) : "st(1)");
|
||
|
|
return res;
|
||
|
|
}
|