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/*
* 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)
fxam
fstsw %ax
sahf
jnc .LnoInf
jp .LisInf
.LnoInf:
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
.LisInf:
andb $2, %ah
jz .LpInf
fldz
.LpInf: ret
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