xref: /freebsd/lib/libc/riscv/gen/fpsetmask.c (revision 5ca8e32633c4ffbbcd6762e5888b6a4ba0708c6c)
1 /*-
2  * Copyright (c) 2020 Axiado
3  * All rights reserved.
4  *
5  * This software was developed by Kristof Provost under
6  * sponsorship from Axiado.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/types.h>
31 #include <ieeefp.h>
32 
33 /**
34  * RISC-V doesn't support floating-point exceptions: RISC-V Instruction Set
35  * Manual: Volume I: User-Level ISA, 11.2 Floating-Point Control and Status
36  * Register: "As allowed by the standard, we do not support traps on
37  * floating-point exceptions in the base ISA, but instead require explicit
38  * checks of the flags in software. We considered adding branches controlled
39  * directly by the contents of the floating-point accrued exception flags, but
40  * ultimately chose to omit these instructions to keep the ISA simple."
41  *
42  * We still need this function, because some applications (notably Perl) call
43  * it, but we cannot provide a meaningful implementation.
44  **/
45 fp_except_t
46 fpsetmask(fp_except_t mask)
47 {
48 
49 	return (0);
50 }
51