fix double-processing of DT_RELR relocations in ldso relocating itself

[musl] / src / math / lgammal.c

diff --git a/src/math/lgammal.c b/src/math/lgammal.c
index 58054e5..abbd4fc 100644 (file)
--- a/src/math/lgammal.c
+++ b/src/math/lgammal.c
@@ -87,11 +87,8 @@
 
 #define _GNU_SOURCE
 #include "libm.h"
-#include "libc.h"
 
 #if LDBL_MANT_DIG == 53 && LDBL_MAX_EXP == 1024
-double __lgamma_r(double x, int *sg);
-
 long double __lgammal_r(long double x, int *sg)
 {
        return __lgamma_r(x, sg);
@@ -99,7 +96,6 @@ long double __lgammal_r(long double x, int *sg)
 #elif LDBL_MANT_DIG == 64 && LDBL_MAX_EXP == 16384
 static const long double
 pi = 3.14159265358979323846264L,
-two63 = 9.223372036854775808e18L,
 
 /* lgam(1+x) = 0.5 x + x a(x)/b(x)
     -0.268402099609375 <= x <= 0
@@ -201,61 +197,27 @@ w5 =  8.412723297322498080632E-4L,
 w6 = -1.880801938119376907179E-3L,
 w7 =  4.885026142432270781165E-3L;
 
+/* sin(pi*x) assuming x > 2^-1000, if sin(pi*x)==0 the sign is arbitrary */
 static long double sin_pi(long double x)
 {
-       union ldshape u = {x};
-       uint32_t ix = (u.i.se & 0x7fffU)<<16 | u.i.m>>48;
-       long double y, z;
        int n;
 
-       if (ix < 0x3ffd8000)  /* 0.25 */
-               return sinl(pi * x);
-       y = -x;  /* x is assume negative */
+       /* spurious inexact if odd int */
+       x *= 0.5;
+       x = 2.0*(x - floorl(x));  /* x mod 2.0 */
 
-       /*
-        * argument reduction, make sure inexact flag not raised if input
-        * is an integer
-        */
-       z = floorl(y);
-       if (z != y) {  /* inexact anyway */
-               y *= 0.5;
-               y = 2.0*(y - floorl(y));/* y = |x| mod 2.0 */
-               n = (int) (y*4.0);
-       } else {
-               if (ix >= 0x403f8000) {  /* 2^64 */
-                       y = 0.0;  /* y must be even */
-                       n = 0;
-               } else {
-                       if (ix < 0x403e8000)  /* 2^63 */
-                               z = y + two63;  /* exact */
-                       u.f = z;
-                       n = u.i.m & 1;
-                       y = n;
-                       n <<= 2;
-               }
-       }
+       n = (int)(x*4.0);
+       n = (n+1)/2;
+       x -= n*0.5f;
+       x *= pi;
 
        switch (n) {
-       case 0:
-               y = sinl(pi * y);
-               break;
-       case 1:
-       case 2:
-               y = cosl(pi * (0.5 - y));
-               break;
-       case 3:
-       case 4:
-               y = sinl(pi * (1.0 - y));
-               break;
-       case 5:
-       case 6:
-               y = -cosl(pi * (y - 1.5));
-               break;
-       default:
-               y = sinl(pi * (y - 2.0));
-               break;
+       default: /* case 4: */
+       case 0: return __sinl(x, 0.0, 0);
+       case 1: return __cosl(x, 0.0);
+       case 2: return __sinl(-x, 0.0, 0);
+       case 3: return -__cosl(x, 0.0);
        }
-       return -y;
 }
 
 long double __lgammal_r(long double x, int *sg) {
@@ -267,31 +229,32 @@ long double __lgammal_r(long double x, int *sg) {
 
        *sg = 1;
 
-       /* purge off +-inf, NaN, +-0, and negative arguments */
+       /* purge off +-inf, NaN, +-0, tiny and negative arguments */
        if (ix >= 0x7fff0000)
                return x * x;
-       if (x == 0) {
-               *sg -= 2*sign;
-               return 1.0 / fabsl(x);
-       }
        if (ix < 0x3fc08000) {  /* |x|<2**-63, return -log(|x|) */
                if (sign) {
                        *sg = -1;
-                       return -logl(-x);
+                       x = -x;
                }
                return -logl(x);
        }
        if (sign) {
-               t = sin_pi (x);
+               x = -x;
+               t = sin_pi(x);
                if (t == 0.0)
-                       return 1.0 / fabsl(t); /* -integer */
-               nadj = logl(pi / fabsl(t * x));
-               if (t < 0.0)
+                       return 1.0 / (x-x); /* -integer */
+               if (t > 0.0)
                        *sg = -1;
-               x = -x;
+               else
+                       t = -t;
+               nadj = logl(pi / (t * x));
        }
 
-       if (ix < 0x40008000) {  /* x < 2.0 */
+       /* purge off 1 and 2 (so the sign is ok with downward rounding) */
+       if ((ix == 0x3fff8000 || ix == 0x40008000) && u.i.m == 0) {
+               r = 0;
+       } else if (ix < 0x40008000) {  /* x < 2.0 */
                if (ix <= 0x3ffee666) {  /* 8.99993896484375e-1 */
                        /* lgamma(x) = lgamma(x+1) - log(x) */
                        r = -logl(x);
@@ -374,10 +337,14 @@ long double __lgammal_r(long double x, int *sg) {
                r = nadj - r;
        return r;
 }
+#elif LDBL_MANT_DIG == 113 && LDBL_MAX_EXP == 16384
+// TODO: broken implementation to make things compile
+long double __lgammal_r(long double x, int *sg)
+{
+       return __lgamma_r(x, sg);
+}
 #endif
 
-extern int __signgam;
-
 long double lgammal(long double x)
 {
        return __lgammal_r(x, &__signgam);