newlib-cygwin/winsup/mingw/mingwex/math/asinl.c

22 lines
445 B
C

/*
* Written by J.T. Conklin <jtc@netbsd.org>.
* Public domain.
* Adapted for long double type by Danny Smith <dannysmith@users.sourceforge.net>.
*/
/* asin = atan (x / sqrt(1 - x^2)) */
long double asinl (long double x)
{
long double res;
asm ( "fld %%st\n\t"
"fmul %%st(0)\n\t" /* x^2 */
"fld1\n\t"
"fsubp\n\t" /* 1 - x^2 */
"fsqrt\n\t" /* sqrt (1 - x^2) */
"fpatan"
: "=t" (res) : "0" (x) : "st(1)");
return res;
}