VEX/test/x87fxam.c

   1
   2 #include <stdio.h>
   3 #include <math.h>
   4
   5 double d;
   6 int i;
   7
   8 extern void do_fxam ( void );
   9
  10 asm(
  11 "\n"
  12 "do_fxam:\n"
  13 "\txorl %eax,%eax\n"
  14 "\tfld d\n"
  15 "\tfxam\n"
  16 "\tfnstsw %ax\n"
  17 "\tffree %st(0)\n"
  18 "\tmovl %eax, i\n"
  19 "\tret\n"
  20 );
  21
  22
  23 double inf ( void ) { return 1.0 / 0.0; }
  24 double nAn ( void ) { return 0.0 / 0.0; }
  25 double den ( void ) { return 9.1e-220 / 1e100; }
  26
  27 /* Try positive and negative variants of: zero, infinity,
  28    nAn, and denorm */
  29
  30 int main ( void )
  31 {
  32    d =  0.0;   do_fxam(); printf("0x%4x: %f\n", i, d );
  33    d = -0.0;   do_fxam(); printf("0x%4x: %f\n", i, d );
  34
  35    d =  inf(); do_fxam(); printf("0x%4x: %f\n", i, d );
  36    d = -inf(); do_fxam(); printf("0x%4x: %f\n", i, d );
  37
  38    d =  nAn(); do_fxam(); printf("0x%4x: %f\n", i, d );
  39    d = -nAn(); do_fxam(); printf("0x%4x: %f\n", i, d );
  40
  41    d =  den(); do_fxam(); printf("0x%4x: %f\n", i, d );
  42    d = -den(); do_fxam(); printf("0x%4x: %f\n", i, d );
  43    return 0;
  44 }