fix broken thread list unlocking after fork

[musl] / src / math / tanl.c

diff --git a/src/math/tanl.c b/src/math/tanl.c
index 3b51e01..6af0671 100644 (file)
--- a/src/math/tanl.c
+++ b/src/math/tanl.c
@@ -1,35 +1,3 @@
-/* origin: FreeBSD /usr/src/lib/msun/src/s_tanl.c */
-/*-
- * Copyright (c) 2007 Steven G. Kargl
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice unmodified, this list of conditions, and the following
- *    disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
- * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
- * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
- * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
- * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
- * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
- * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-/*
- * Limited testing on pseudorandom numbers drawn within [0:4e8] shows
- * an accuracy of <= 1.5 ULP where 247024 values of x out of 40 million
- * possibles resulted in tan(x) that exceeded 0.5 ULP (ie., 0.6%).
- */
-
 #include "libm.h"
 
 #if LDBL_MANT_DIG == 53 && LDBL_MAX_EXP == 1024
@@ -40,27 +8,21 @@ long double tanl(long double x)
 #elif (LDBL_MANT_DIG == 64 || LDBL_MANT_DIG == 113) && LDBL_MAX_EXP == 16384
 long double tanl(long double x)
 {
-       union IEEEl2bits z;
+       union ldshape u = {x};
        long double y[2];
        unsigned n;
 
-       z.e = x;
-       z.bits.sign = 0;
-
-       /* If x = NaN or Inf, then tan(x) = NaN. */
-       if (z.bits.exp == 0x7fff)
-               return (x - x) / (x - x);
-
-       /* |x| < (double)pi/4 */
-       if (z.e < M_PI_4) {
-               /* x = +-0 or x is subnormal */
-               if (z.bits.exp == 0)
-                       /* inexact and underflow if x!=0 */
-                       return x + x*0x1p-120f;
-               /* can raise spurious underflow */
+       u.i.se &= 0x7fff;
+       if (u.i.se == 0x7fff)
+               return x - x;
+       if (u.f < M_PI_4) {
+               if (u.i.se < 0x3fff - LDBL_MANT_DIG/2) {
+                       /* raise inexact if x!=0 and underflow if subnormal */
+                       FORCE_EVAL(u.i.se == 0 ? x*0x1p-120f : x+0x1p120f);
+                       return x;
+               }
                return __tanl(x, 0, 0);
        }
-
        n = __rem_pio2l(x, y);
        return __tanl(y[0], y[1], n&1);
 }