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-rw-r--r--usr/src/lib/libm/common/Q/__lgammal.c397
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diff --git a/usr/src/lib/libm/common/Q/__lgammal.c b/usr/src/lib/libm/common/Q/__lgammal.c
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index 0000000000..3b1f8eff75
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+++ b/usr/src/lib/libm/common/Q/__lgammal.c
@@ -0,0 +1,397 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License (the "License").
+ * You may not use this file except in compliance with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+
+/*
+ * Copyright 2011 Nexenta Systems, Inc. All rights reserved.
+ */
+/*
+ * Copyright 2006 Sun Microsystems, Inc. All rights reserved.
+ * Use is subject to license terms.
+ */
+
+/*
+ * long double __k_lgammal(long double x, int *signgamlp);
+ * K.C. Ng, August, 1989.
+ *
+ * We choose [1.5,2.5] to be the primary interval. Our algorithms
+ * are mainly derived from
+ *
+ *
+ * zeta(2)-1 2 zeta(3)-1 3
+ * lgamma(2+s) = s*(1-euler) + --------- * s - --------- * s + ...
+ * 2 3
+ *
+ *
+ * Note 1. Since gamma(1+s)=s*gamma(s), hence
+ * lgamma(1+s) = log(s) + lgamma(s), or
+ * lgamma(s) = lgamma(1+s) - log(s).
+ * When s is really tiny (like roundoff), lgamma(1+s) ~ s(1-enler)
+ * Hence lgamma(s) ~ -log(s) for tiny s
+ *
+ */
+
+#include "libm.h"
+#include "longdouble.h"
+
+static long double neg(long double, int *);
+static long double poly(long double, const long double *, int);
+static long double polytail(long double);
+static long double primary(long double);
+
+static const long double
+c0 = 0.0L,
+ch = 0.5L,
+c1 = 1.0L,
+c2 = 2.0L,
+c3 = 3.0L,
+c4 = 4.0L,
+c5 = 5.0L,
+c6 = 6.0L,
+pi = 3.1415926535897932384626433832795028841971L,
+tiny = 1.0e-40L;
+
+long double
+__k_lgammal(long double x, int *signgamlp) {
+ long double t,y;
+ int i;
+
+ /* purge off +-inf, NaN and negative arguments */
+ if (!finitel(x)) return x*x;
+ *signgamlp = 1;
+ if (signbitl(x)) return (neg(x,signgamlp));
+
+ /* for x < 8.0 */
+ if (x<8.0L) {
+ y = anintl(x);
+ i = (int) y;
+ switch(i) {
+ case 0:
+ if (x<1.0e-40L) return -logl(x); else
+ return (primary(x)-log1pl(x))-logl(x);
+ case 1:
+ return primary(x-y)-logl(x);
+ case 2:
+ return primary(x-y);
+ case 3:
+ return primary(x-y)+logl(x-c1);
+ case 4:
+ return primary(x-y)+logl((x-c1)*(x-c2));
+ case 5:
+ return primary(x-y)+logl((x-c1)*(x-c2)*(x-c3));
+ case 6:
+ return primary(x-y)+logl((x-c1)*(x-c2)*(x-c3)*(x-c4));
+ case 7:
+ return primary(x-y)+logl((x-c1)*(x-c2)*(x-c3)*(x-c4)*(x-c5));
+ case 8:
+ return primary(x-y)+
+ logl((x-c1)*(x-c2)*(x-c3)*(x-c4)*(x-c5)*(x-c6));
+ }
+ }
+
+ /* 8.0 <= x < 1.0e40 */
+ if (x < 1.0e40L) {
+ t = logl(x);
+ return x*(t-c1)-(ch*t-polytail(c1/x));
+ }
+
+ /* 1.0e40 <= x <= inf */
+ return x*(logl(x)-c1);
+}
+
+static const long double an1[] = { /* 20 terms */
+ -0.0772156649015328606065120900824024309741L,
+ 3.224670334241132182362075833230130289059e-0001L,
+ -6.735230105319809513324605383668929964120e-0002L,
+ 2.058080842778454787900092432928910226297e-0002L,
+ -7.385551028673985266273054086081102125704e-0003L,
+ 2.890510330741523285758867304409628648727e-0003L,
+ -1.192753911703260976581414338096267498555e-0003L,
+ 5.096695247430424562831956662855697824035e-0004L,
+ -2.231547584535777978926798502084300123638e-0004L,
+ 9.945751278186384670278268034322157947635e-0005L,
+ -4.492623673665547726647838474125147631082e-0005L,
+ 2.050721280617796810096993154281561168706e-0005L,
+ -9.439487785617396552092393234044767313568e-0006L,
+ 4.374872903516051510689234173139793159340e-0006L,
+ -2.039156676413643091040459825776029327487e-0006L,
+ 9.555777181318621470466563543806211523634e-0007L,
+ -4.468344919709630637558538313482398989638e-0007L,
+ 2.216738086090045781773004477831059444178e-0007L,
+ -7.472783403418388455860445842543843485916e-0008L,
+ 8.777317930927149922056782132706238921648e-0008L,
+};
+
+static const long double an2[] = { /* 20 terms */
+ -.0772156649015328606062692723698127607018L,
+ 3.224670334241132182635552349060279118047e-0001L,
+ -6.735230105319809367555642883133994818325e-0002L,
+ 2.058080842778459676880822202762143671813e-0002L,
+ -7.385551028672828216011343150077846918930e-0003L,
+ 2.890510330762060607399561536905727853178e-0003L,
+ -1.192753911419623262328187532759756368041e-0003L,
+ 5.096695278636456678258091134532258618614e-0004L,
+ -2.231547306817535743052975194022893369135e-0004L,
+ 9.945771461633313282744264853986643877087e-0005L,
+ -4.492503279458972037926876061257489481619e-0005L,
+ 2.051311416812082875492678651369394595613e-0005L,
+ -9.415778282365955203915850761537462941165e-0006L,
+ 4.452428829045147098722932981088650055919e-0006L,
+ -1.835024727987632579886951760650722695781e-0006L,
+ 1.379783080658545009579060714946381462565e-0006L,
+ 2.282637532109775156769736768748402175238e-0007L,
+ 1.002577375515900191362119718128149880168e-0006L,
+ 5.177028794262638311939991106423220002463e-0007L,
+ 3.127947245174847104122426445937830555755e-0007L,
+};
+
+static const long double an3[] = { /* 20 terms */
+ -.0772156649015328227870646417729220690875L,
+ 3.224670334241156699881788955959915250365e-0001L,
+ -6.735230105312273571375431059744975563170e-0002L,
+ 2.058080842924464587662846071337083809005e-0002L,
+ -7.385551008677271654723604653956131791619e-0003L,
+ 2.890510536479782086197110272583833176602e-0003L,
+ -1.192752262076857692740571567808259138697e-0003L,
+ 5.096800771149805289371135155128380707889e-0004L,
+ -2.231000836682831335505058492409860123647e-0004L,
+ 9.968912171073936803871803966360595275047e-0005L,
+ -4.412020779327746243544387946167256187258e-0005L,
+ 2.281374113541454151067016632998630209049e-0005L,
+ -4.028361291428629491824694655287954266830e-0006L,
+ 1.470694920619518924598956849226530750139e-0005L,
+ 1.381686137617987197975289545582377713772e-0005L,
+ 2.012493539265777728944759982054970441601e-0005L,
+ 1.723917864208965490251560644681933675799e-0005L,
+ 1.202954035243788300138608765425123713395e-0005L,
+ 5.079851887558623092776296577030850938146e-0006L,
+ 1.220657945824153751555138592006604026282e-0006L,
+};
+
+static const long double an4[] = { /* 21 terms */
+ -.0772156649015732285350261816697540392371L,
+ 3.224670334221752060691751340365212226097e-0001L,
+ -6.735230109744009693977755991488196368279e-0002L,
+ 2.058080778913037626909954141611580783216e-0002L,
+ -7.385557567931505621170483708950557506819e-0003L,
+ 2.890459838416254326340844289785254883436e-0003L,
+ -1.193059036207136762877351596966718455737e-0003L,
+ 5.081914708100372836613371356529568937869e-0004L,
+ -2.289855016133600313131553005982542045338e-0004L,
+ 8.053454537980585879620331053833498511491e-0005L,
+ -9.574620532104845821243493405855672438998e-0005L,
+ -9.269085628207107155601445001196317715686e-0005L,
+ -2.183276779859490461716196344776208220180e-0004L,
+ -3.134834305597571096452454999737269668868e-0004L,
+ -3.973878894951937437018305986901392888619e-0004L,
+ -3.953352414899222799161275564386488057119e-0004L,
+ -3.136740932204038779362660900621212816511e-0004L,
+ -1.884502253819634073946130825196078627664e-0004L,
+ -8.192655799958926853585332542123631379301e-0005L,
+ -2.292183750010571062891605074281744854436e-0005L,
+ -3.223980628729716864927724265781406614294e-0006L,
+};
+
+static const long double ap1[] = { /* 19 terms */
+ -0.0772156649015328606065120900824024296961L,
+ 3.224670334241132182362075833230047956465e-0001L,
+ -6.735230105319809513324605382963943777301e-0002L,
+ 2.058080842778454787900092126606252375465e-0002L,
+ -7.385551028673985266272518231365020063941e-0003L,
+ 2.890510330741523285681704570797770736423e-0003L,
+ -1.192753911703260971285304221165990244515e-0003L,
+ 5.096695247430420878696018188830886972245e-0004L,
+ -2.231547584535654004647639737841526025095e-0004L,
+ 9.945751278137201960636098805852315982919e-0005L,
+ -4.492623672777606053587919463929044226280e-0005L,
+ 2.050721258703289487603702670753053765201e-0005L,
+ -9.439485626565616989352750672499008021041e-0006L,
+ 4.374838162403994645138200419356844574219e-0006L,
+ -2.038979492862555348577006944451002161496e-0006L,
+ 9.536763152382263548086981191378885102802e-0007L,
+ -4.426111214332434049863595231916564014913e-0007L,
+ 1.911148847512947464234633846270287546882e-0007L,
+ -5.788673944861923038157839080272303519671e-0008L,
+};
+
+static const long double ap2[] = { /* 19 terms */
+ -0.077215664901532860606428624449354836087L,
+ 3.224670334241132182271948744265855440139e-0001L,
+ -6.735230105319809467356126599005051676203e-0002L,
+ 2.058080842778453315716389815213496002588e-0002L,
+ -7.385551028673653323064118422580096222959e-0003L,
+ 2.890510330735923572088003424849289006039e-0003L,
+ -1.192753911629952368606185543945790688144e-0003L,
+ 5.096695239806718875364547587043220998766e-0004L,
+ -2.231547520600616108991867127392089144886e-0004L,
+ 9.945746913898151120612322833059416008973e-0005L,
+ -4.492599307461977003570224943054585729684e-0005L,
+ 2.050609891889165453592046505651759999090e-0005L,
+ -9.435329866734193796540515247917165988579e-0006L,
+ 4.362267138522223236241016136585565144581e-0006L,
+ -2.008556356653246579300491601497510230557e-0006L,
+ 8.961498103387207161105347118042844354395e-0007L,
+ -3.614187228330216282235692806488341157741e-0007L,
+ 1.136978988247816860500420915014777753153e-0007L,
+ -2.000532786387196664019286514899782691776e-0008L,
+};
+
+static const long double ap3[] = { /* 19 terms */
+ -0.077215664901532859888521470795348856446L,
+ 3.224670334241131733364048614484228443077e-0001L,
+ -6.735230105319676541660495145259038151576e-0002L,
+ 2.058080842775975461837768839015444273830e-0002L,
+ -7.385551028347615729728618066663566606906e-0003L,
+ 2.890510327517954083379032008643080256676e-0003L,
+ -1.192753886919470728001821137439430882603e-0003L,
+ 5.096693728898932234814903769146577482912e-0004L,
+ -2.231540055048827662528594010961874258037e-0004L,
+ 9.945446210018649311491619999438833843723e-0005L,
+ -4.491608206598064519190236245753867697750e-0005L,
+ 2.047939071322271016498065052853746466669e-0005L,
+ -9.376824046522786006677541036631536790762e-0006L,
+ 4.259329829498149111582277209189150127347e-0006L,
+ -1.866064770421594266702176289764212873428e-0006L,
+ 7.462066721137579592928128104534957135669e-0007L,
+ -2.483546217529077735074007138457678727371e-0007L,
+ 5.915166576378161473299324673649144297574e-0008L,
+ -7.334139641706988966966252333759604701905e-0009L,
+};
+
+static const long double ap4[] = { /* 19 terms */
+ -0.0772156649015326785569313252637238673675L,
+ 3.224670334241051435008842685722468344822e-0001L,
+ -6.735230105302832007479431772160948499254e-0002L,
+ 2.058080842553481183648529360967441889912e-0002L,
+ -7.385551007602909242024706804659879199244e-0003L,
+ 2.890510182473907253939821312248303471206e-0003L,
+ -1.192753098427856770847894497586825614450e-0003L,
+ 5.096659636418811568063339214203693550804e-0004L,
+ -2.231421144004355691166194259675004483639e-0004L,
+ 9.942073842343832132754332881883387625136e-0005L,
+ -4.483809261973204531263252655050701205397e-0005L,
+ 2.033260142610284888319116654931994447173e-0005L,
+ -9.153539544026646699870528191410440585796e-0006L,
+ 3.988460469925482725894144688699584997971e-0006L,
+ -1.609692980087029172567957221850825977621e-0006L,
+ 5.634916377249975825399706694496688803488e-0007L,
+ -1.560065465929518563549083208482591437696e-0007L,
+ 2.961350193868935325526962209019387821584e-0008L,
+ -2.834602215195368130104649234505033159842e-0009L,
+};
+
+static long double
+primary(long double s) { /* assume |s|<=0.5 */
+ int i;
+
+ i = (int) (8.0L * (s + 0.5L));
+ switch(i) {
+ case 0: return ch*s+s*poly(s,an4,21);
+ case 1: return ch*s+s*poly(s,an3,20);
+ case 2: return ch*s+s*poly(s,an2,20);
+ case 3: return ch*s+s*poly(s,an1,20);
+ case 4: return ch*s+s*poly(s,ap1,19);
+ case 5: return ch*s+s*poly(s,ap2,19);
+ case 6: return ch*s+s*poly(s,ap3,19);
+ case 7: return ch*s+s*poly(s,ap4,19);
+ }
+ /* NOTREACHED */
+ return 0.0L;
+}
+
+static long double
+poly(long double s, const long double *p, int n) {
+ long double y;
+ int i;
+ y = p[n-1];
+ for (i=n-2;i>=0;i--) y = p[i]+s*y;
+ return y;
+}
+
+static const long double pt[] = {
+ 9.189385332046727417803297364056176804663e-0001L,
+ 8.333333333333333333333333333331286969123e-0002L,
+ -2.777777777777777777777777553194796036402e-0003L,
+ 7.936507936507936507927283071433584248176e-0004L,
+ -5.952380952380952362351042163192634108297e-0004L,
+ 8.417508417508395661774286645578379460131e-0004L,
+ -1.917526917525263651186066417934685675649e-0003L,
+ 6.410256409395203164659292973142293199083e-0003L,
+ -2.955065327248303301763594514012418438188e-0002L,
+ 1.796442830099067542945998615411893822886e-0001L,
+ -1.392413465829723742489974310411118662919e+0000L,
+ 1.339984238037267658352656597960492029261e+0001L,
+ -1.564707657605373662425785904278645727813e+0002L,
+ 2.156323807499211356127813962223067079300e+0003L,
+ -3.330486427626223184647299834137041307569e+0004L,
+ 5.235535072011889213611369254140123518699e+0005L,
+ -7.258160984602220710491988573430212593080e+0006L,
+ 7.316526934569686459641438882340322673357e+0007L,
+ -3.806450279064900548836571789284896711473e+0008L,
+};
+
+static long double
+polytail(long double s) {
+ long double t,z;
+ int i;
+ z = s*s;
+ t = pt[18];
+ for (i=17;i>=1;i--) t = pt[i]+z*t;
+ return pt[0]+s*t;
+}
+
+static long double
+neg(long double z, int *signgamlp) {
+ long double t,p;
+
+ /*
+ * written by K.C. Ng, Feb 2, 1989.
+ *
+ * Since
+ * -z*G(-z)*G(z) = pi/sin(pi*z),
+ * we have
+ * G(-z) = -pi/(sin(pi*z)*G(z)*z)
+ * = pi/(sin(pi*(-z))*G(z)*z)
+ * Algorithm
+ * z = |z|
+ * t = sinpi(z); ...note that when z>2**112, z is an int
+ * and hence t=0.
+ *
+ * if (t == 0.0) return 1.0/0.0;
+ * if (t< 0.0) *signgamlp = -1; else t= -t;
+ * if (z<1.0e-40) ...tiny z
+ * return -log(z);
+ * else
+ * return log(pi/(t*z))-lgamma(z);
+ *
+ */
+
+ t = sinpil(z); /* t := sin(pi*z) */
+ if (t == c0) /* return 1.0/0.0 = +INF */
+ return c1/c0;
+
+ z = -z;
+ if (z<=tiny)
+ p = -logl(z);
+ else
+ p = logl(pi/(fabsl(t)*z))-__k_lgammal(z,signgamlp);
+ if (t<c0) *signgamlp = -1;
+ return p;
+}