diff options
Diffstat (limited to 'winsup/mingw/mingwex/math/acosf.c')
| -rw-r--r-- | winsup/mingw/mingwex/math/acosf.c | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/winsup/mingw/mingwex/math/acosf.c b/winsup/mingw/mingwex/math/acosf.c new file mode 100644 index 000000000..364f6a90c --- /dev/null +++ b/winsup/mingw/mingwex/math/acosf.c @@ -0,0 +1,23 @@ +/* + * 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; +} |