diff options
Diffstat (limited to 'sysdeps/libm-i387/e_exp.S')
| -rw-r--r-- | sysdeps/libm-i387/e_exp.S | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/sysdeps/libm-i387/e_exp.S b/sysdeps/libm-i387/e_exp.S new file mode 100644 index 0000000000..8c41ce09dd --- /dev/null +++ b/sysdeps/libm-i387/e_exp.S @@ -0,0 +1,23 @@ +/* + * Written by J.T. Conklin <jtc@netbsd.org>. + * Public domain. + */ + +#include <machine/asm.h> + +RCSID("$NetBSD: e_exp.S,v 1.4 1995/05/08 23:47:04 jtc Exp $") + +/* e^x = 2^(x * log2(e)) */ +ENTRY(__ieee754_exp) + fldl 4(%esp) + fldl2e + fmulp /* x * log2(e) */ + fstl %st(1) + frndint /* int(x * log2(e)) */ + fstl %st(2) + fsubrp /* fract(x * log2(e)) */ + f2xm1 /* 2^(fract(x * log2(e))) - 1 */ + fld1 + faddp /* 2^(fract(x * log2(e))) */ + fscale /* e^x */ + ret |