xref: /freebsd/lib/libc/arm/gen/flt_rounds.c (revision 7082a2cf72f2af64cd8554012cac6427a0c8e641)
186d131a0SDavid Schultz /*-
286d131a0SDavid Schultz  * Copyright (c) 2012 Ian Lepore <freebsd@damnhippie.dyndns.org>
386d131a0SDavid Schultz  * All rights reserved.
486d131a0SDavid Schultz  *
586d131a0SDavid Schultz  * Redistribution and use in source and binary forms, with or without
686d131a0SDavid Schultz  * modification, are permitted provided that the following conditions
786d131a0SDavid Schultz  * are met:
886d131a0SDavid Schultz  * 1. Redistributions of source code must retain the above copyright
986d131a0SDavid Schultz  *    notice, this list of conditions and the following disclaimer.
1086d131a0SDavid Schultz  * 2. Redistributions in binary form must reproduce the above copyright
1186d131a0SDavid Schultz  *    notice, this list of conditions and the following disclaimer in the
1286d131a0SDavid Schultz  *    documentation and/or other materials provided with the distribution.
1386d131a0SDavid Schultz  *
1486d131a0SDavid Schultz  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
1586d131a0SDavid Schultz  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
1686d131a0SDavid Schultz  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
1786d131a0SDavid Schultz  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
1886d131a0SDavid Schultz  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
1986d131a0SDavid Schultz  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
2086d131a0SDavid Schultz  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
2186d131a0SDavid Schultz  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
2286d131a0SDavid Schultz  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
2386d131a0SDavid Schultz  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
2486d131a0SDavid Schultz  * SUCH DAMAGE.
2586d131a0SDavid Schultz  */
2686d131a0SDavid Schultz 
2786d131a0SDavid Schultz #include <sys/cdefs.h>
2886d131a0SDavid Schultz __FBSDID("$FreeBSD$");
2986d131a0SDavid Schultz 
3086d131a0SDavid Schultz #include <fenv.h>
3186d131a0SDavid Schultz #include <float.h>
3286d131a0SDavid Schultz 
33*7082a2cfSDavid Schultz #include "softfloat-for-gcc.h"
34*7082a2cfSDavid Schultz #include "milieu.h"
3586d131a0SDavid Schultz #include "softfloat.h"
3686d131a0SDavid Schultz 
3786d131a0SDavid Schultz int
3886d131a0SDavid Schultz __flt_rounds(void)
3986d131a0SDavid Schultz {
4086d131a0SDavid Schultz 
4186d131a0SDavid Schultz #ifndef ARM_HARD_FLOAT
4286d131a0SDavid Schultz 	/*
4386d131a0SDavid Schultz 	 * Translate our rounding modes to the unnamed
4486d131a0SDavid Schultz 	 * manifest constants required by C99 et. al.
4586d131a0SDavid Schultz 	 */
4686d131a0SDavid Schultz 	switch (__softfloat_float_rounding_mode) {
4786d131a0SDavid Schultz 	case FE_TOWARDZERO:
4886d131a0SDavid Schultz 		return (0);
4986d131a0SDavid Schultz 	case FE_TONEAREST:
5086d131a0SDavid Schultz 		return (1);
5186d131a0SDavid Schultz 	case FE_UPWARD:
5286d131a0SDavid Schultz 		return (2);
5386d131a0SDavid Schultz 	case FE_DOWNWARD:
5486d131a0SDavid Schultz 		return (3);
5586d131a0SDavid Schultz 	}
5686d131a0SDavid Schultz 	return (-1);
5786d131a0SDavid Schultz #else /* ARM_HARD_FLOAT */
5886d131a0SDavid Schultz 	/*
5986d131a0SDavid Schultz 	 * Apparently, the rounding mode is specified as part of the
6086d131a0SDavid Schultz 	 * instruction format on ARM, so the dynamic rounding mode is
6186d131a0SDavid Schultz 	 * indeterminate.  Some FPUs may differ.
6286d131a0SDavid Schultz 	 */
6386d131a0SDavid Schultz 	return (-1);
6486d131a0SDavid Schultz #endif /* ARM_HARD_FLOAT */
6586d131a0SDavid Schultz }
66