gnu/dist/gdb6/libiberty/copysign.c

   1 #include <ansidecl.h>
   2
   3 #ifdef __IEEE_BIG_ENDIAN
   4
   5 typedef union
   6 {
   7   double value;
   8   struct
   9   {
  10     unsigned int sign : 1;
  11     unsigned int exponent: 11;
  12     unsigned int fraction0:4;
  13     unsigned int fraction1:16;
  14     unsigned int fraction2:16;
  15     unsigned int fraction3:16;
  16
  17   } number;
  18   struct
  19   {
  20     unsigned int sign : 1;
  21     unsigned int exponent: 11;
  22     unsigned int quiet:1;
  23     unsigned int function0:3;
  24     unsigned int function1:16;
  25     unsigned int function2:16;
  26     unsigned int function3:16;
  27   } nan;
  28   struct
  29   {
  30     unsigned long msw;
  31     unsigned long lsw;
  32   } parts;
  33     long aslong[2];
  34 } __ieee_double_shape_type;
  35
  36 #endif
  37
  38 #ifdef __IEEE_LITTLE_ENDIAN
  39
  40 typedef union
  41 {
  42   double value;
  43   struct
  44   {
  45 #ifdef __SMALL_BITFIELDS
  46     unsigned int fraction3:16;
  47     unsigned int fraction2:16;
  48     unsigned int fraction1:16;
  49     unsigned int fraction0: 4;
  50 #else
  51     unsigned int fraction1:32;
  52     unsigned int fraction0:20;
  53 #endif
  54     unsigned int exponent :11;
  55     unsigned int sign     : 1;
  56   } number;
  57   struct
  58   {
  59 #ifdef __SMALL_BITFIELDS
  60     unsigned int function3:16;
  61     unsigned int function2:16;
  62     unsigned int function1:16;
  63     unsigned int function0:3;
  64 #else
  65     unsigned int function1:32;
  66     unsigned int function0:19;
  67 #endif
  68     unsigned int quiet:1;
  69     unsigned int exponent: 11;
  70     unsigned int sign : 1;
  71   } nan;
  72   struct
  73   {
  74     unsigned long lsw;
  75     unsigned long msw;
  76   } parts;
  77
  78   long aslong[2];
  79
  80 } __ieee_double_shape_type;
  81
  82 #endif
  83
  84 #ifdef __IEEE_BIG_ENDIAN
  85 typedef union
  86 {
  87   float value;
  88   struct
  89   {
  90     unsigned int sign : 1;
  91     unsigned int exponent: 8;
  92     unsigned int fraction0: 7;
  93     unsigned int fraction1: 16;
  94   } number;
  95   struct
  96   {
  97     unsigned int sign:1;
  98     unsigned int exponent:8;
  99     unsigned int quiet:1;
 100     unsigned int function0:6;
 101     unsigned int function1:16;
 102   } nan;
 103   long p1;
 104
 105 } __ieee_float_shape_type;
 106 #endif
 107
 108 #ifdef __IEEE_LITTLE_ENDIAN
 109 typedef union
 110 {
 111   float value;
 112   struct
 113   {
 114     unsigned int fraction0: 7;
 115     unsigned int fraction1: 16;
 116     unsigned int exponent: 8;
 117     unsigned int sign : 1;
 118   } number;
 119   struct
 120   {
 121     unsigned int function1:16;
 122     unsigned int function0:6;
 123     unsigned int quiet:1;
 124     unsigned int exponent:8;
 125     unsigned int sign:1;
 126   } nan;
 127   long p1;
 128
 129 } __ieee_float_shape_type;
 130 #endif
 131
 132 #if defined(__IEEE_BIG_ENDIAN) || defined(__IEEE_LITTLE_ENDIAN)
 133
 134 double
 135 copysign (double x, double y)
 136 {
 137   __ieee_double_shape_type a,b;
 138   b.value = y;
 139   a.value = x;
 140   a.number.sign =b.number.sign;
 141   return a.value;
 142 }
 143
 144 #else
 145
 146 double
 147 copysign (double x, double y)
 148 {
 149   if ((x < 0 && y > 0) || (x > 0 && y < 0))
 150     return -x;
 151   return x;
 152 }
 153
 154 #endif