diff options
Diffstat (limited to 'lib/libc/alpha/gen/fpsetround.c')
-rw-r--r-- | lib/libc/alpha/gen/fpsetround.c | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/lib/libc/alpha/gen/fpsetround.c b/lib/libc/alpha/gen/fpsetround.c new file mode 100644 index 0000000..c28093c --- /dev/null +++ b/lib/libc/alpha/gen/fpsetround.c @@ -0,0 +1,58 @@ +/* $NetBSD: fpsetround.c,v 1.1 1995/04/29 05:09:57 cgd Exp $ */ + +/* + * Copyright (c) 1995 Christopher G. Demetriou + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by Christopher G. Demetriou + * for the NetBSD Project. + * 4. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include <sys/types.h> +#include <ieeefp.h> + +fp_rnd +fpsetround(rnd_dir) + fp_rnd rnd_dir; +{ + double fpcrval; + u_int64_t old, new; + + __asm__("trapb"); + __asm__("mf_fpcr %0" : "=f" (fpcrval)); + __asm__("trapb"); + old = *(u_int64_t *)&fpcrval; + + new = old & ~(long)0x0c00000000000000; + new = (long)rnd_dir << 58; + *(u_int64_t *)&fpcrval = new; + + __asm__("trapb"); + __asm__("mt_fpcr %0" : : "f" (fpcrval)); + __asm__("trapb"); + + return ((old >> 58) & 0x3); +} |