1*e415d488SLionel Sambuc /* $NetBSD: fpsetround.c,v 1.6 2012/03/23 09:34:09 skrll Exp $ */ 22fe8fb19SBen Gras 32fe8fb19SBen Gras /* $OpenBSD: fpsetround.c,v 1.3 2002/10/21 18:41:05 mickey Exp $ */ 42fe8fb19SBen Gras 52fe8fb19SBen Gras /* 62fe8fb19SBen Gras * Written by Miodrag Vallat. Public domain 72fe8fb19SBen Gras */ 82fe8fb19SBen Gras 92fe8fb19SBen Gras #include <sys/cdefs.h> 102fe8fb19SBen Gras #if defined(LIBC_SCCS) && !defined(lint) 11*e415d488SLionel Sambuc __RCSID("$NetBSD: fpsetround.c,v 1.6 2012/03/23 09:34:09 skrll Exp $"); 122fe8fb19SBen Gras #endif /* LIBC_SCCS and not lint */ 132fe8fb19SBen Gras 142fe8fb19SBen Gras #include <sys/types.h> 152fe8fb19SBen Gras #include <ieeefp.h> 162fe8fb19SBen Gras 172fe8fb19SBen Gras fp_rnd fpsetround(fp_rnd rnd_dir)182fe8fb19SBen Grasfpsetround(fp_rnd rnd_dir) 192fe8fb19SBen Gras { 202fe8fb19SBen Gras uint64_t fpsr; 212fe8fb19SBen Gras fp_rnd old; 222fe8fb19SBen Gras 232fe8fb19SBen Gras __asm volatile("fstd %%fr0,0(%1)" : "=m" (fpsr) : "r" (&fpsr) : "memory"); 24*e415d488SLionel Sambuc old = (fp_rnd)(fpsr >> 41) & 0x03; 252fe8fb19SBen Gras fpsr = (fpsr & 0xfffff9ff00000000LL) | 262fe8fb19SBen Gras ((uint64_t)(rnd_dir & 0x03) << 41); 272fe8fb19SBen Gras __asm volatile("fldd 0(%0),%%fr0" : : "r" (&fpsr) : "memory"); 282fe8fb19SBen Gras return (old); 292fe8fb19SBen Gras } 30