math: raise invalid flag in ilogb*.c on +-0, +-inf and nan

[musl] / src / math / lgammal.c

diff --git a/src/math/lgammal.c b/src/math/lgammal.c
index a33707a..56d7866 100644 (file)
--- a/src/math/lgammal.c
+++ b/src/math/lgammal.c
@@ -88,20 +88,15 @@
 #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,
 
@@ -205,8 +200,6 @@ w5 =  8.412723297322498080632E-4L,
 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;
@@ -231,7 +224,7 @@ static long double sin_pi(long double x)
                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 */
@@ -249,11 +242,11 @@ static long double sin_pi(long double x)
                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:
@@ -266,7 +259,7 @@ static long double sin_pi(long double x)
        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;
@@ -278,7 +271,7 @@ long double lgammal_r(long double x, int *sg) {
        if ((ix | i0 | i1) == 0) {
                if (se & 0x8000)
                        *sg = -1;
-               return one / fabsl(x);
+               return 1.0 / fabsl(x);
        }
 
        ix = (ix << 16) | (i0 >> 16);
@@ -296,10 +289,10 @@ long double lgammal_r(long double x, int *sg) {
        }
        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;
        }
@@ -311,19 +304,19 @@ long double lgammal_r(long double x, int *sg) {
        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;
@@ -334,7 +327,7 @@ long double lgammal_r(long double x, int *sg) {
                                i = 1;
                        } else {
                                /* [0.9, 1.23] */
-                               y = x - one;
+                               y = x - 1.0;
                                i = 2;
                        }
                }
@@ -342,7 +335,7 @@ long double lgammal_r(long double x, int *sg) {
                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)))));
@@ -353,17 +346,17 @@ long double lgammal_r(long double x, int *sg) {
                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 */
@@ -375,20 +368,29 @@ long double lgammal_r(long double x, int *sg) {
                        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);