1 2#include <stdio.h> 3#include <math.h> 4 5double d; 6int i; 7 8extern void do_fxam ( void ); 9 10asm( 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 23double inf ( void ) { return 1.0 / 0.0; } 24double nAn ( void ) { return 0.0 / 0.0; } 25double den ( void ) { return 9.1e-220 / 1e100; } 26 27/* Try positive and negative variants of: zero, infinity, 28 nAn, and denorm */ 29 30int 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} 45