X-Git-Url: http://nsz.repo.hu/git/?p=musl;a=blobdiff_plain;f=src%2Fmath%2F__invtrigl.c;h=f2d33d3e5314fc458164b080d28c5a05deec6096;hp=a821842c03c73f3e9f8fb1c9213d8e5a2573372d;hb=697acde67e0da4d73b46445ed536fe9923d515c7;hpb=b69f695acedd4ce2798ef9ea28d834ceccc789bd diff --git a/src/math/__invtrigl.c b/src/math/__invtrigl.c index a821842c..f2d33d3e 100644 --- a/src/math/__invtrigl.c +++ b/src/math/__invtrigl.c @@ -1,37 +1,8 @@ -/* origin: FreeBSD /usr/src/lib/msun/src/ld80/invtrig.c */ -/*- - * Copyright (c) 2008 David Schultz - * All rights reserved. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * 2. Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in the - * documentation and/or other materials provided with the distribution. - * - * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND - * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE - * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE - * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE - * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL - * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS - * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) - * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT - * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY - * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF - * SUCH DAMAGE. - */ - #include "__invtrigl.h" #if LDBL_MANT_DIG == 64 && LDBL_MAX_EXP == 16384 -/* - * asinl() and acosl() - */ -const long double + +static const long double pS0 = 1.66666666666666666631e-01L, pS1 = -4.16313987993683104320e-01L, pS2 = 3.69068046323246813704e-01L, @@ -45,38 +16,16 @@ qS3 = -1.68285799854822427013e+00L, qS4 = 3.90699412641738801874e-01L, qS5 = -3.14365703596053263322e-02L; -/* - * atanl() - */ -const long double atanhi[] = { - 4.63647609000806116202e-01L, - 7.85398163397448309628e-01L, - 9.82793723247329067960e-01L, - 1.57079632679489661926e+00L, -}; - -const long double atanlo[] = { - 1.18469937025062860669e-20L, - -1.25413940316708300586e-20L, - 2.55232234165405176172e-20L, - -2.50827880633416601173e-20L, -}; - -const long double aT[] = { - 3.33333333333333333017e-01L, - -1.99999999999999632011e-01L, - 1.42857142857046531280e-01L, - -1.11111111100562372733e-01L, - 9.09090902935647302252e-02L, - -7.69230552476207730353e-02L, - 6.66661718042406260546e-02L, - -5.88158892835030888692e-02L, - 5.25499891539726639379e-02L, - -4.70119845393155721494e-02L, - 4.03539201366454414072e-02L, - -2.91303858419364158725e-02L, - 1.24822046299269234080e-02L, -}; +const long double pio2_hi = 1.57079632679489661926L; +const long double pio2_lo = -2.50827880633416601173e-20L; -const long double pi_lo = -5.01655761266833202345e-20L; +/* used in asinl() and acosl() */ +/* R(x^2) is a rational approximation of (asin(x)-x)/x^3 with Remez algorithm */ +long double __invtrigl_R(long double z) +{ + long double p, q; + p = z*(pS0+z*(pS1+z*(pS2+z*(pS3+z*(pS4+z*(pS5+z*pS6)))))); + q = 1.0+z*(qS1+z*(qS2+z*(qS3+z*(qS4+z*qS5)))); + return p/q; +} #endif