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  • Committer: Package Import Robot
  • Author(s): Sylvestre Ledru
  • Date: 2014-01-19 14:12:40 UTC
  • mfrom: (4.1.2 sid)
  • Revision ID: package-import@ubuntu.com-20140119141240-nfiw0p8033oitpfz
Tags: 1.9.0~20140119~7dc8c2f-1
http://bugs.debian.org/733714
http://bugs.debian.org/735903
* New snapshot release (Closes: #733714)
* Provide sources for javascript and flash. Done in orig-tar.sh
  Available in third_party/websockify/include/web-socket-js/src/
  (Closes: #735903)

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system/lib/libc/musl/src/math/lgammaf_r.c
 
1
/* origin: FreeBSD /usr/src/lib/msun/src/e_lgammaf_r.c */
 
2
/*
 
3
 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
 
4
 */
 
5
/*
 
6
 * ====================================================
 
7
 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
 
8
 *
 
9
 * Developed at SunPro, a Sun Microsystems, Inc. business.
 
10
 * Permission to use, copy, modify, and distribute this
 
11
 * software is freely granted, provided that this notice
 
12
 * is preserved.
 
13
 * ====================================================
 
14
 */
 
15
 
 
16
#include "libm.h"
 
17
#include "libc.h"
 
18
 
 
19
static const float
 
20
two23= 8.3886080000e+06, /* 0x4b000000 */
 
21
pi  =  3.1415927410e+00, /* 0x40490fdb */
 
22
a0  =  7.7215664089e-02, /* 0x3d9e233f */
 
23
a1  =  3.2246702909e-01, /* 0x3ea51a66 */
 
24
a2  =  6.7352302372e-02, /* 0x3d89f001 */
 
25
a3  =  2.0580807701e-02, /* 0x3ca89915 */
 
26
a4  =  7.3855509982e-03, /* 0x3bf2027e */
 
27
a5  =  2.8905137442e-03, /* 0x3b3d6ec6 */
 
28
a6  =  1.1927076848e-03, /* 0x3a9c54a1 */
 
29
a7  =  5.1006977446e-04, /* 0x3a05b634 */
 
30
a8  =  2.2086278477e-04, /* 0x39679767 */
 
31
a9  =  1.0801156895e-04, /* 0x38e28445 */
 
32
a10 =  2.5214456400e-05, /* 0x37d383a2 */
 
33
a11 =  4.4864096708e-05, /* 0x383c2c75 */
 
34
tc  =  1.4616321325e+00, /* 0x3fbb16c3 */
 
35
tf  = -1.2148628384e-01, /* 0xbdf8cdcd */
 
36
/* tt = -(tail of tf) */
 
37
tt  =  6.6971006518e-09, /* 0x31e61c52 */
 
38
t0  =  4.8383611441e-01, /* 0x3ef7b95e */
 
39
t1  = -1.4758771658e-01, /* 0xbe17213c */
 
40
t2  =  6.4624942839e-02, /* 0x3d845a15 */
 
41
t3  = -3.2788541168e-02, /* 0xbd064d47 */
 
42
t4  =  1.7970675603e-02, /* 0x3c93373d */
 
43
t5  = -1.0314224288e-02, /* 0xbc28fcfe */
 
44
t6  =  6.1005386524e-03, /* 0x3bc7e707 */
 
45
t7  = -3.6845202558e-03, /* 0xbb7177fe */
 
46
t8  =  2.2596477065e-03, /* 0x3b141699 */
 
47
t9  = -1.4034647029e-03, /* 0xbab7f476 */
 
48
t10 =  8.8108185446e-04, /* 0x3a66f867 */
 
49
t11 = -5.3859531181e-04, /* 0xba0d3085 */
 
50
t12 =  3.1563205994e-04, /* 0x39a57b6b */
 
51
t13 = -3.1275415677e-04, /* 0xb9a3f927 */
 
52
t14 =  3.3552918467e-04, /* 0x39afe9f7 */
 
53
u0  = -7.7215664089e-02, /* 0xbd9e233f */
 
54
u1  =  6.3282704353e-01, /* 0x3f2200f4 */
 
55
u2  =  1.4549225569e+00, /* 0x3fba3ae7 */
 
56
u3  =  9.7771751881e-01, /* 0x3f7a4bb2 */
 
57
u4  =  2.2896373272e-01, /* 0x3e6a7578 */
 
58
u5  =  1.3381091878e-02, /* 0x3c5b3c5e */
 
59
v1  =  2.4559779167e+00, /* 0x401d2ebe */
 
60
v2  =  2.1284897327e+00, /* 0x4008392d */
 
61
v3  =  7.6928514242e-01, /* 0x3f44efdf */
 
62
v4  =  1.0422264785e-01, /* 0x3dd572af */
 
63
v5  =  3.2170924824e-03, /* 0x3b52d5db */
 
64
s0  = -7.7215664089e-02, /* 0xbd9e233f */
 
65
s1  =  2.1498242021e-01, /* 0x3e5c245a */
 
66
s2  =  3.2577878237e-01, /* 0x3ea6cc7a */
 
67
s3  =  1.4635047317e-01, /* 0x3e15dce6 */
 
68
s4  =  2.6642270386e-02, /* 0x3cda40e4 */
 
69
s5  =  1.8402845599e-03, /* 0x3af135b4 */
 
70
s6  =  3.1947532989e-05, /* 0x3805ff67 */
 
71
r1  =  1.3920053244e+00, /* 0x3fb22d3b */
 
72
r2  =  7.2193557024e-01, /* 0x3f38d0c5 */
 
73
r3  =  1.7193385959e-01, /* 0x3e300f6e */
 
74
r4  =  1.8645919859e-02, /* 0x3c98bf54 */
 
75
r5  =  7.7794247773e-04, /* 0x3a4beed6 */
 
76
r6  =  7.3266842264e-06, /* 0x36f5d7bd */
 
77
w0  =  4.1893854737e-01, /* 0x3ed67f1d */
 
78
w1  =  8.3333335817e-02, /* 0x3daaaaab */
 
79
w2  = -2.7777778450e-03, /* 0xbb360b61 */
 
80
w3  =  7.9365057172e-04, /* 0x3a500cfd */
 
81
w4  = -5.9518753551e-04, /* 0xba1c065c */
 
82
w5  =  8.3633989561e-04, /* 0x3a5b3dd2 */
 
83
w6  = -1.6309292987e-03; /* 0xbad5c4e8 */
 
84
 
 
85
static float sin_pif(float x)
 
86
{
 
87
        float y,z;
 
88
        int n,ix;
 
89
 
 
90
        GET_FLOAT_WORD(ix, x);
 
91
        ix &= 0x7fffffff;
 
92
 
 
93
        if(ix < 0x3e800000)
 
94
                return __sindf(pi*x);
 
95
 
 
96
        y = -x;  /* negative x is assumed */
 
97
 
 
98
        /*
 
99
         * argument reduction, make sure inexact flag not raised if input
 
100
         * is an integer
 
101
         */
 
102
        z = floorf(y);
 
103
        if (z != y) {   /* inexact anyway */
 
104
                y *= 0.5f;
 
105
                y  = 2.0f*(y - floorf(y));   /* y = |x| mod 2.0 */
 
106
                n  = (int)(y*4.0f);
 
107
        } else {
 
108
                if (ix >= 0x4b800000) {
 
109
                        y = 0.0f;  /* y must be even */
 
110
                        n = 0;
 
111
                } else {
 
112
                        if (ix < 0x4b000000)
 
113
                                z = y + two23;  /* exact */
 
114
                        GET_FLOAT_WORD(n, z);
 
115
                        n &= 1;
 
116
                        y = n;
 
117
                        n <<= 2;
 
118
                }
 
119
        }
 
120
        switch (n) {
 
121
        case 0:  y =  __sindf(pi*y); break;
 
122
        case 1:
 
123
        case 2:  y =  __cosdf(pi*(0.5f - y)); break;
 
124
        case 3:
 
125
        case 4:  y =  __sindf(pi*(1.0f - y)); break;
 
126
        case 5:
 
127
        case 6:  y = -__cosdf(pi*(y - 1.5f)); break;
 
128
        default: y =  __sindf(pi*(y - 2.0f)); break;
 
129
        }
 
130
        return -y;
 
131
}
 
132
 
 
133
 
 
134
float __lgammaf_r(float x, int *signgamp)
 
135
{
 
136
        float t,y,z,nadj,p,p1,p2,p3,q,r,w;
 
137
        int32_t hx;
 
138
        int i,ix;
 
139
 
 
140
        GET_FLOAT_WORD(hx, x);
 
141
 
 
142
        /* purge off +-inf, NaN, +-0, tiny and negative arguments */
 
143
        *signgamp = 1;
 
144
        ix = hx & 0x7fffffff;
 
145
        if (ix >= 0x7f800000)
 
146
                return x*x;
 
147
        if (ix == 0)
 
148
                return 1.0f/0.0f;
 
149
        if (ix < 0x35000000) {  /* |x| < 2**-21, return -log(|x|) */
 
150
                if (hx < 0) {
 
151
                        *signgamp = -1;
 
152
                        return -logf(-x);
 
153
                }
 
154
                return -logf(x);
 
155
        }
 
156
        if (hx < 0) {
 
157
                if (ix >= 0x4b000000)  /* |x| >= 2**23, must be -integer */
 
158
                        return 1.0f/0.0f;
 
159
                t = sin_pif(x);
 
160
                if (t == 0.0f) /* -integer */
 
161
                        return 1.0f/0.0f;
 
162
                nadj = logf(pi/fabsf(t*x));
 
163
                if (t < 0.0f)
 
164
                        *signgamp = -1;
 
165
                x = -x;
 
166
        }
 
167
 
 
168
        /* purge off 1 and 2 */
 
169
        if (ix == 0x3f800000 || ix == 0x40000000)
 
170
                r = 0;
 
171
        /* for x < 2.0 */
 
172
        else if (ix < 0x40000000) {
 
173
                if (ix <= 0x3f666666) {  /* lgamma(x) = lgamma(x+1)-log(x) */
 
174
                        r = -logf(x);
 
175
                        if (ix >= 0x3f3b4a20) {
 
176
                                y = 1.0f - x;
 
177
                                i = 0;
 
178
                        } else if (ix >= 0x3e6d3308) {
 
179
                                y = x - (tc-1.0f);
 
180
                                i = 1;
 
181
                        } else {
 
182
                                y = x;
 
183
                                i = 2;
 
184
                        }
 
185
                } else {
 
186
                        r = 0.0f;
 
187
                        if (ix >= 0x3fdda618) {  /* [1.7316,2] */
 
188
                                y = 2.0f - x;
 
189
                                i = 0;
 
190
                        } else if (ix >= 0x3F9da620) {  /* [1.23,1.73] */
 
191
                                y = x - tc;
 
192
                                i = 1;
 
193
                        } else {
 
194
                                y = x - 1.0f;
 
195
                                i = 2;
 
196
                        }
 
197
                }
 
198
                switch(i) {
 
199
                case 0:
 
200
                        z = y*y;
 
201
                        p1 = a0+z*(a2+z*(a4+z*(a6+z*(a8+z*a10))));
 
202
                        p2 = z*(a1+z*(a3+z*(a5+z*(a7+z*(a9+z*a11)))));
 
203
                        p = y*p1+p2;
 
204
                        r += p - 0.5f*y;
 
205
                        break;
 
206
                case 1:
 
207
                        z = y*y;
 
208
                        w = z*y;
 
209
                        p1 = t0+w*(t3+w*(t6+w*(t9 +w*t12)));    /* parallel comp */
 
210
                        p2 = t1+w*(t4+w*(t7+w*(t10+w*t13)));
 
211
                        p3 = t2+w*(t5+w*(t8+w*(t11+w*t14)));
 
212
                        p = z*p1-(tt-w*(p2+y*p3));
 
213
                        r += (tf + p);
 
214
                        break;
 
215
                case 2:
 
216
                        p1 = y*(u0+y*(u1+y*(u2+y*(u3+y*(u4+y*u5)))));
 
217
                        p2 = 1.0f+y*(v1+y*(v2+y*(v3+y*(v4+y*v5))));
 
218
                        r += -0.5f*y + p1/p2;
 
219
                }
 
220
        } else if (ix < 0x41000000) {  /* x < 8.0 */
 
221
                i = (int)x;
 
222
                y = x - (float)i;
 
223
                p = y*(s0+y*(s1+y*(s2+y*(s3+y*(s4+y*(s5+y*s6))))));
 
224
                q = 1.0f+y*(r1+y*(r2+y*(r3+y*(r4+y*(r5+y*r6)))));
 
225
                r = 0.5f*y+p/q;
 
226
                z = 1.0f;    /* lgamma(1+s) = log(s) + lgamma(s) */
 
227
                switch (i) {
 
228
                case 7: z *= y + 6.0f;  /* FALLTHRU */
 
229
                case 6: z *= y + 5.0f;  /* FALLTHRU */
 
230
                case 5: z *= y + 4.0f;  /* FALLTHRU */
 
231
                case 4: z *= y + 3.0f;  /* FALLTHRU */
 
232
                case 3: z *= y + 2.0f;  /* FALLTHRU */
 
233
                        r += logf(z);
 
234
                        break;
 
235
                }
 
236
        } else if (ix < 0x5c800000) {  /* 8.0 <= x < 2**58 */
 
237
                t = logf(x);
 
238
                z = 1.0f/x;
 
239
                y = z*z;
 
240
                w = w0+z*(w1+y*(w2+y*(w3+y*(w4+y*(w5+y*w6)))));
 
241
                r = (x-0.5f)*(t-1.0f)+w;
 
242
        } else                         /* 2**58 <= x <= inf */
 
243
                r =  x*(logf(x)-1.0f);
 
244
        if (hx < 0)
 
245
                r = nadj - r;
 
246
        return r;
 
247
}
 
248
 
 
249
weak_alias(__lgammaf_r, lgammaf_r);