1/* $OpenBSD: e_acos.S,v 1.6 2018/07/03 22:43:34 mortimer Exp $ */ 2/* 3 * Written by J.T. Conklin <jtc@NetBSD.org>. 4 * Public domain. 5 */ 6 7#include <machine/asm.h> 8 9#include "abi.h" 10 11/* acos = atan (sqrt(1 - x^2) / x) */ 12ENTRY(acos) 13 RETGUARD_SETUP(acos, r11) 14 XMM_ONE_ARG_DOUBLE_PROLOGUE 15 fldl ARG_DOUBLE_ONE /* x */ 16 fld %st(0) 17 fmul %st(0) /* x^2 */ 18 fld1 19 fsubp /* 1 - x^2 */ 20 fsqrt /* sqrt (1 - x^2) */ 21 fxch %st(1) 22 fpatan 23 XMM_DOUBLE_EPILOGUE 24 RETGUARD_CHECK(acos, r11) 25 ret 26END(acos) 27