diff options
Diffstat (limited to 'lib/libc/aarch64/gen/flt_rounds.c')
-rw-r--r-- | lib/libc/aarch64/gen/flt_rounds.c | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/lib/libc/aarch64/gen/flt_rounds.c b/lib/libc/aarch64/gen/flt_rounds.c new file mode 100644 index 0000000..6f8eeeb --- /dev/null +++ b/lib/libc/aarch64/gen/flt_rounds.c @@ -0,0 +1,49 @@ +/*- + * Copyright (c) 2012 Ian Lepore <freebsd@damnhippie.dyndns.org> + * 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. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include <sys/types.h> + +#include <fenv.h> +#include <float.h> + +static int map[] = { + 1, /* round to nearest */ + 2, /* round to positive infinity */ + 3, /* round to negative infinity */ + 0 /* round to zero */ +}; + +int +__flt_rounds(void) +{ + uint64_t fpcr; + + asm volatile("mrs %0, fpcr" : "=r" (fpcr)); + return map[(fpcr >> 22) & 3]; +} |