sysdeps/ieee754/dbl-64/s_finite.c

   1 /*
   2  * ====================================================
   3  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
   4  *
   5  * Developed at SunPro, a Sun Microsystems, Inc. business.
   6  * Permission to use, copy, modify, and distribute this
   7  * software is freely granted, provided that this notice
   8  * is preserved.
   9  * ====================================================
  10  */
  11
  12 /*
  13  * finite(x) returns 1 is x is finite, else 0;
  14  * no branching!
  15  */
  16
  17 #include <math.h>
  18 #include <math_private.h>
  19 #include <ldbl-classify-compat.h>
  20 #include <shlib-compat.h>
  21 #include <stdint.h>
  22
  23 int
  24 __finite (double x)
  25 {
  26   int64_t lx;
  27   EXTRACT_WORDS64 (lx,x);
  28   return (int)((uint64_t)((lx & INT64_C(0x7ff0000000000000))
  29                           - INT64_C (0x7ff0000000000000)) >> 63);
  30 }
  31 hidden_def (__finite)
  32 weak_alias (__finite, finite)
  33 #ifdef NO_LONG_DOUBLE
  34 # if LDBL_CLASSIFY_COMPAT
  35 #  if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_23)
  36 compat_symbol (libc, __finite, __finitel, GLIBC_2_0);
  37 #  endif
  38 #  if SHLIB_COMPAT (libm, GLIBC_2_1, GLIBC_2_23)
  39 compat_symbol (libm, __finite, __finitel, GLIBC_2_1);
  40 #  endif
  41 # endif
  42 weak_alias (__finite, finitel)
  43 #endif