/* $OpenBSD: s_truncf.c,v 1.6 2023/01/27 16:43:33 miod Exp $ */ /* * Written by Michael Shalayeff. Public Domain */ #include #include #include "math.h" float truncf(float x) { u_int64_t ofpsr, fpsr; __asm__ volatile("fstds %%fr0,0(%1)" : "=m" (ofpsr) : "r" (&ofpsr)); fpsr = (ofpsr & ~((u_int64_t)FP_RM << (9 + 32))) | ((u_int64_t)FP_RZ << (9 + 32)); __asm__ volatile("fldds 0(%0), %%fr0" :: "r" (&fpsr), "m" (fpsr)); __asm__ volatile("frnd,sgl %0,%0" : "+f" (x)); __asm__ volatile("fldds 0(%0), %%fr0" :: "r" (&ofpsr), "m" (ofpsr)); return (x); }