1 /* $NetBSD: flt_rounds.c,v 1.4 2005/12/24 21:42:32 perry Exp $ */ 2 3 /* $OpenBSD: flt_rounds.c,v 1.3 2002/10/21 18:41:05 mickey Exp $ */ 4 5 /* 6 * Written by Miodrag Vallat. Public domain. 7 */ 8 9 #include <sys/cdefs.h> 10 #if defined(LIBC_SCCS) && !defined(lint) 11 __RCSID("$NetBSD: flt_rounds.c,v 1.4 2005/12/24 21:42:32 perry Exp $"); 12 #endif /* LIBC_SCCS and not lint */ 13 14 #include <sys/types.h> 15 #include <machine/float.h> 16 17 static const int map[] = { 18 1, /* round to nearest */ 19 0, /* round to zero */ 20 2, /* round to positive infinity */ 21 3 /* round to negative infinity */ 22 }; 23 24 int 25 __flt_rounds(void) 26 { 27 uint64_t fpsr; 28 29 __asm volatile("fstd %%fr0,0(%1)" : "=m" (fpsr) : "r" (&fpsr)); 30 return map[(fpsr >> 41) & 0x03]; 31 } 32