*
*/
+#define _GNU_SOURCE
#include "libm.h"
-long double lgammal(long double x)
-{
- return lgammal_r(x, &signgam);
-}
-
#if LDBL_MANT_DIG == 53 && LDBL_MAX_EXP == 1024
-long double lgammal_r(long double x, int *sg)
+double __lgamma_r(double x, int *sg);
+
+long double __lgammal_r(long double x, int *sg)
{
- return lgamma_r(x, sg);
+ return __lgamma_r(x, sg);
}
#elif LDBL_MANT_DIG == 64 && LDBL_MAX_EXP == 16384
static const long double
-half = 0.5L,
-one = 1.0L,
pi = 3.14159265358979323846264L,
two63 = 9.223372036854775808e18L,
w6 = -1.880801938119376907179E-3L,
w7 = 4.885026142432270781165E-3L;
-static const long double zero = 0.0L;
-
static long double sin_pi(long double x)
{
long double y, z;
n = (int) (y*4.0);
} else {
if (ix >= 0x403f8000) { /* 2^64 */
- y = zero; /* y must be even */
+ y = 0.0; /* y must be even */
n = 0;
} else {
if (ix < 0x403e8000) /* 2^63 */
break;
case 1:
case 2:
- y = cosl(pi * (half - y));
+ y = cosl(pi * (0.5 - y));
break;
case 3:
case 4:
- y = sinl(pi * (one - y));
+ y = sinl(pi * (1.0 - y));
break;
case 5:
case 6:
return -y;
}
-long double lgammal_r(long double x, int *sg) {
+long double __lgammal_r(long double x, int *sg) {
long double t, y, z, nadj, p, p1, p2, q, r, w;
int i, ix;
uint32_t se, i0, i1;
if ((ix | i0 | i1) == 0) {
if (se & 0x8000)
*sg = -1;
- return one / fabsl(x);
+ return 1.0 / fabsl(x);
}
ix = (ix << 16) | (i0 >> 16);
}
if (se & 0x8000) {
t = sin_pi (x);
- if (t == zero)
- return one / fabsl(t); /* -integer */
+ if (t == 0.0)
+ return 1.0 / fabsl(t); /* -integer */
nadj = logl(pi / fabsl(t * x));
- if (t < zero)
+ if (t < 0.0)
*sg = -1;
x = -x;
}
else if (ix < 0x40008000) { /* x < 2.0 */
if (ix <= 0x3ffee666) { /* 8.99993896484375e-1 */
/* lgamma(x) = lgamma(x+1) - log(x) */
- r = -logl (x);
+ r = -logl(x);
if (ix >= 0x3ffebb4a) { /* 7.31597900390625e-1 */
- y = x - one;
+ y = x - 1.0;
i = 0;
} else if (ix >= 0x3ffced33) { /* 2.31639862060546875e-1 */
- y = x - (tc - one);
+ y = x - (tc - 1.0);
i = 1;
} else { /* x < 0.23 */
y = x;
i = 2;
}
} else {
- r = zero;
+ r = 0.0;
if (ix >= 0x3fffdda6) { /* 1.73162841796875 */
/* [1.7316,2] */
y = x - 2.0;
i = 1;
} else {
/* [0.9, 1.23] */
- y = x - one;
+ y = x - 1.0;
i = 2;
}
}
case 0:
p1 = a0 + y * (a1 + y * (a2 + y * (a3 + y * (a4 + y * a5))));
p2 = b0 + y * (b1 + y * (b2 + y * (b3 + y * (b4 + y))));
- r += half * y + y * p1/p2;
+ r += 0.5 * y + y * p1/p2;
break;
case 1:
p1 = g0 + y * (g1 + y * (g2 + y * (g3 + y * (g4 + y * (g5 + y * g6)))));
case 2:
p1 = y * (u0 + y * (u1 + y * (u2 + y * (u3 + y * (u4 + y * (u5 + y * u6))))));
p2 = v0 + y * (v1 + y * (v2 + y * (v3 + y * (v4 + y * (v5 + y)))));
- r += (-half * y + p1 / p2);
+ r += (-0.5 * y + p1 / p2);
}
} else if (ix < 0x40028000) { /* 8.0 */
/* x < 8.0 */
i = (int)x;
- t = zero;
+ t = 0.0;
y = x - (double)i;
p = y * (s0 + y * (s1 + y * (s2 + y * (s3 + y * (s4 + y * (s5 + y * s6))))));
q = r0 + y * (r1 + y * (r2 + y * (r3 + y * (r4 + y * (r5 + y * (r6 + y))))));
- r = half * y + p / q;
- z = one;/* lgamma(1+s) = log(s) + lgamma(s) */
+ r = 0.5 * y + p / q;
+ z = 1.0;/* lgamma(1+s) = log(s) + lgamma(s) */
switch (i) {
case 7:
z *= (y + 6.0); /* FALLTHRU */
z *= (y + 3.0); /* FALLTHRU */
case 3:
z *= (y + 2.0); /* FALLTHRU */
- r += logl (z);
+ r += logl(z);
break;
}
} else if (ix < 0x40418000) { /* 2^66 */
/* 8.0 <= x < 2**66 */
- t = logl (x);
- z = one / x;
+ t = logl(x);
+ z = 1.0 / x;
y = z * z;
w = w0 + z * (w1 + y * (w2 + y * (w3 + y * (w4 + y * (w5 + y * (w6 + y * w7))))));
- r = (x - half) * (t - one) + w;
+ r = (x - 0.5) * (t - 1.0) + w;
} else /* 2**66 <= x <= inf */
- r = x * (logl (x) - one);
+ r = x * (logl(x) - 1.0);
if (se & 0x8000)
r = nadj - r;
return r;
}
#endif
+
+extern int __signgam;
+
+long double lgammal(long double x)
+{
+ return __lgammal_r(x, &__signgam);
+}
+
+weak_alias(__lgammal_r, lgammal_r);