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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 */
+ fld %st /* x : x */
+ fmul %st(0) /* x^2 : x */
+ fld1 /* 1 : x^2 : x */
+ fsubp /* 1 - x^2 : x */
+ fsqrt /* sqrt (1 - x^2) : x */
+ fxch %st(1) /* x : sqrt (1 - x^2) */
+ fpatan /* atan (sqrt(1 - x^2) / x) */
+ ret
+END (__ieee754_acos)