86 lines
3.2 KiB
C
86 lines
3.2 KiB
C
/*
|
|
(c) Copyright 2017 Michael R. Neilly
|
|
All rights reserved.
|
|
|
|
Redistribution and use in source and binary forms, with or without
|
|
modification, are permitted provided that the following conditions
|
|
are met:
|
|
|
|
* Redistributions of source code must retain the above copyright
|
|
notice, this list of conditions and the following disclaimer.
|
|
|
|
* 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.
|
|
|
|
* Neither the names of the copyright holders nor the names of their
|
|
contributors may be used to endorse or promote products derived from
|
|
this software without specific prior written permission.
|
|
|
|
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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
|
|
COPYRIGHT OWNER 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 <fenv.h>
|
|
|
|
/* This implementation is intended to comply with the following
|
|
* specification:
|
|
*
|
|
* http://pubs.opengroup.org/onlinepubs/009695399/functions/feraiseexcept.html
|
|
* Referred to as 'feraiseexcept.html below.
|
|
*
|
|
* "The feraiseexcept() function shall attempt to raise the supported
|
|
* floating-point exceptions represented by the excepts argument. The
|
|
* order in which these floating-point exceptions are raised is
|
|
* unspecified, except that if the excepts argument represents IEC
|
|
* 60559 valid coincident floating-point exceptions for atomic
|
|
* operations (namely overflow and inexact, or underflow and inexact),
|
|
* then overflow or underflow shall be raised before inexact. Whether
|
|
* the feraiseexcept() function additionally raises the inexact
|
|
* floating-point exception whenever it raises the overflow or
|
|
* underflow floating-point exception is implementation-defined."
|
|
*/
|
|
|
|
int feraiseexcept(int excepts)
|
|
{
|
|
|
|
/* Mask excepts to be sure only supported flag bits are set */
|
|
|
|
excepts &= FE_ALL_EXCEPT;
|
|
|
|
#if __riscv_flen
|
|
|
|
/* Set the requested exception flags */
|
|
|
|
asm volatile("csrs fflags, %0" : : "r"(excepts));
|
|
|
|
/* Per 'feraiseexcept.html:
|
|
* "If the argument is zero or if all the specified exceptions were
|
|
* successfully raised, feraiseexcept() shall return
|
|
* zero. Otherwise, it shall return a non-zero value."
|
|
*/
|
|
|
|
/* Per "The RISC-V Instruction Set Manual: Volume I: User-Level ISA:
|
|
* Version 2.1":
|
|
*
|
|
* "As allowed by the standard, we do not support traps on
|
|
* floating-point exceptions in the base ISA, but instead require
|
|
* explicit checks of the flags in software."
|
|
*
|
|
*/
|
|
|
|
#endif
|
|
|
|
return (excepts != 0);
|
|
}
|