1*5b9a4216Sskrll /* $NetBSD: fpsetround.c,v 1.6 2012/03/23 09:34:09 skrll Exp $ */ 295a63d48Schs 395a63d48Schs /* $OpenBSD: fpsetround.c,v 1.3 2002/10/21 18:41:05 mickey Exp $ */ 495a63d48Schs 595a63d48Schs /* 695a63d48Schs * Written by Miodrag Vallat. Public domain 795a63d48Schs */ 895a63d48Schs 988c3eadbSlukem #include <sys/cdefs.h> 1088c3eadbSlukem #if defined(LIBC_SCCS) && !defined(lint) 11*5b9a4216Sskrll __RCSID("$NetBSD: fpsetround.c,v 1.6 2012/03/23 09:34:09 skrll Exp $"); 1288c3eadbSlukem #endif /* LIBC_SCCS and not lint */ 1388c3eadbSlukem 1495a63d48Schs #include <sys/types.h> 1595a63d48Schs #include <ieeefp.h> 1695a63d48Schs 1795a63d48Schs fp_rnd fpsetround(fp_rnd rnd_dir)1895a63d48Schsfpsetround(fp_rnd rnd_dir) 1995a63d48Schs { 2095a63d48Schs uint64_t fpsr; 2195a63d48Schs fp_rnd old; 2295a63d48Schs 2314c5fc5dSskrll __asm volatile("fstd %%fr0,0(%1)" : "=m" (fpsr) : "r" (&fpsr) : "memory"); 24*5b9a4216Sskrll old = (fp_rnd)(fpsr >> 41) & 0x03; 2595a63d48Schs fpsr = (fpsr & 0xfffff9ff00000000LL) | 2695a63d48Schs ((uint64_t)(rnd_dir & 0x03) << 41); 2714c5fc5dSskrll __asm volatile("fldd 0(%0),%%fr0" : : "r" (&fpsr) : "memory"); 2895a63d48Schs return (old); 2995a63d48Schs } 30