X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=src%2Fmath%2F__invtrigl.c;h=ef7f4e1b79ebbe29bb80799e0876438504648466;hb=a2a328bd896fa909542b492601e3689119b95de0;hp=a821842c03c73f3e9f8fb1c9213d8e5a2573372d;hpb=b69f695acedd4ce2798ef9ea28d834ceccc789bd;p=musl

diff --git a/src/math/__invtrigl.c b/src/math/__invtrigl.c
index a821842c..ef7f4e1b 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 <das@FreeBSD.ORG>
- * 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 <float.h>
 #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 +16,48 @@ 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 pio2_hi = 1.57079632679489661926L;
+const long double pio2_lo = -2.50827880633416601173e-20L;
 
-const long double atanlo[] = {
-	 1.18469937025062860669e-20L,
-	-1.25413940316708300586e-20L,
-	 2.55232234165405176172e-20L,
-	-2.50827880633416601173e-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;
+}
+#elif LDBL_MANT_DIG == 113 && LDBL_MAX_EXP == 16384
+static const long double
+pS0 =  1.66666666666666666666666666666700314e-01L,
+pS1 = -7.32816946414566252574527475428622708e-01L,
+pS2 =  1.34215708714992334609030036562143589e+00L,
+pS3 = -1.32483151677116409805070261790752040e+00L,
+pS4 =  7.61206183613632558824485341162121989e-01L,
+pS5 = -2.56165783329023486777386833928147375e-01L,
+pS6 =  4.80718586374448793411019434585413855e-02L,
+pS7 = -4.42523267167024279410230886239774718e-03L,
+pS8 =  1.44551535183911458253205638280410064e-04L,
+pS9 = -2.10558957916600254061591040482706179e-07L,
+qS1 = -4.84690167848739751544716485245697428e+00L,
+qS2 =  9.96619113536172610135016921140206980e+00L,
+qS3 = -1.13177895428973036660836798461641458e+01L,
+qS4 =  7.74004374389488266169304117714658761e+00L,
+qS5 = -3.25871986053534084709023539900339905e+00L,
+qS6 =  8.27830318881232209752469022352928864e-01L,
+qS7 = -1.18768052702942805423330715206348004e-01L,
+qS8 =  8.32600764660522313269101537926539470e-03L,
+qS9 = -1.99407384882605586705979504567947007e-04L;
 
-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 = 1.57079632679489661923132169163975140L;
+const long double pio2_lo = 4.33590506506189051239852201302167613e-35L;
 
-const long double pi_lo = -5.01655761266833202345e-20L;
+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+z*(pS7+z*(pS8+z*pS9)))))))));
+	q = 1.0+z*(qS1+z*(qS2+z*(qS3+z*(qS4+z*(qS5+z*(pS6+z*(pS7+z*(pS8+z*pS9))))))));
+	return p/q;
+}
 #endif