1 /* 2 * Written by Michael Shalayeff. Public Domain 3 */ 4 5 #include <sys/types.h> 6 #include <machine/ieeefp.h> 7 #include "math.h" 8 9 double 10 trunc(double x) 11 { 12 u_int64_t ofpsr, fpsr; 13 14 __asm__ __volatile__("fstds %%fr0,0(%0)" :: "r" (&ofpsr) : "memory"); 15 fpsr = (ofpsr & ~((u_int64_t)FP_RM << (9 + 32))) | 16 ((u_int64_t)FP_RZ << (9 + 32)); 17 __asm__ __volatile__("fldds 0(%0), %%fr0" :: "r" (&fpsr) : "memory"); 18 19 __asm__ __volatile__("frnd,dbl %0,%0" : "+f" (x)); 20 21 __asm__ __volatile__("fldds 0(%0), %%fr0" :: "r" (&ofpsr) : "memory"); 22 return (x); 23 } 24