sysdeps/libm-i387/e_acos.S


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/*
 * Written by J.T. Conklin <jtc@netbsd.org>.
 * Public domain.
 */

#include <machine/asm.h>

RCSID("$NetBSD: e_acos.S,v 1.4 1995/05/08 23:44:37 jtc Exp $")

/* acos = atan (sqrt(1 - x^2) / x) */
ENTRY(__ieee754_acos)
	fldl	4(%esp)			/* x */
	fst	%st(1)
	fmul	%st(0)			/* x^2 */
	fld1
	fsubp				/* 1 - x^2 */
	fsqrt				/* sqrt (1 - x^2) */
	fxch	%st(1)
	fpatan
	ret
PSEUDO_END (__ieee754_acos)