1 /* 2 * Written by J.T. Conklin, Apr 10, 1995 3 * Public domain. 4 * 5 * $FreeBSD: head/lib/libc/amd64/gen/flt_rounds.c 132383 2004-07-19 08:17:25Z das $ 6 */ 7 8 #include <float.h> 9 10 static const int map[] = { 11 1, /* round to nearest */ 12 3, /* round to zero */ 13 2, /* round to negative infinity */ 14 0 /* round to positive infinity */ 15 }; 16 17 int 18 __flt_rounds(void) 19 { 20 int x; 21 22 /* Assume that the x87 and the SSE unit agree on the rounding mode. */ 23 __asm("fnstcw %0" : "=m" (x)); 24 return (map[(x >> 10) & 0x03]); 25 } 26