xref: /freebsd/lib/libc/arm/gen/arm_initfini.c (revision 559a218c9b257775fb249b67945fe4a05b7a6b9f)
18e03dd59SAndrew Turner /*-
2*b61a5730SWarner Losh  * SPDX-License-Identifier: BSD-2-Clause
3d915a14eSPedro F. Giffuni  *
48e03dd59SAndrew Turner  * Copyright (c) 2013 The NetBSD Foundation, Inc.
58e03dd59SAndrew Turner  * Copyright (c) 2013 Andrew Turner
68e03dd59SAndrew Turner  * All rights reserved.
78e03dd59SAndrew Turner  *
88e03dd59SAndrew Turner  * This code is derived from software contributed to The NetBSD Foundation
98e03dd59SAndrew Turner  * by Matt Thomas of 3am Software Foundry.
108e03dd59SAndrew Turner  *
118e03dd59SAndrew Turner  * Redistribution and use in source and binary forms, with or without
128e03dd59SAndrew Turner  * modification, are permitted provided that the following conditions
138e03dd59SAndrew Turner  * are met:
148e03dd59SAndrew Turner  * 1. Redistributions of source code must retain the above copyright
158e03dd59SAndrew Turner  *    notice, this list of conditions and the following disclaimer.
168e03dd59SAndrew Turner  * 2. Redistributions in binary form must reproduce the above copyright
178e03dd59SAndrew Turner  *    notice, this list of conditions and the following disclaimer in the
188e03dd59SAndrew Turner  *    documentation and/or other materials provided with the distribution.
198e03dd59SAndrew Turner  *
208e03dd59SAndrew Turner  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
218e03dd59SAndrew Turner  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
228e03dd59SAndrew Turner  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
238e03dd59SAndrew Turner  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
248e03dd59SAndrew Turner  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
258e03dd59SAndrew Turner  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
268e03dd59SAndrew Turner  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
278e03dd59SAndrew Turner  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
288e03dd59SAndrew Turner  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
298e03dd59SAndrew Turner  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
308e03dd59SAndrew Turner  * POSSIBILITY OF SUCH DAMAGE.
318e03dd59SAndrew Turner  *
328e03dd59SAndrew Turner  * Bases on NetBSD lib/libc/arch/arm/misc/arm_initfini.c
338e03dd59SAndrew Turner  * $NetBSD: arm_initfini.c,v 1.2 2013/01/31 06:47:55 matt Exp $
348e03dd59SAndrew Turner  */
358e03dd59SAndrew Turner 
368e03dd59SAndrew Turner /*
378e03dd59SAndrew Turner  * To properly implement setjmp/longjmp for the ARM AAPCS ABI, it has to be
388e03dd59SAndrew Turner  * aware of whether there is a FPU is present or not.  Regardless of whether
398e03dd59SAndrew Turner  * the hard-float ABI is being used, setjmp needs to save D8-D15.  But it can
408e03dd59SAndrew Turner  * only do this if those instructions won't cause an exception.
418e03dd59SAndrew Turner  */
428e03dd59SAndrew Turner 
438e03dd59SAndrew Turner #include <sys/param.h>
448e03dd59SAndrew Turner #include <sys/sysctl.h>
458e03dd59SAndrew Turner 
468e03dd59SAndrew Turner #include <stdbool.h>
478e03dd59SAndrew Turner #include <stddef.h>
488e03dd59SAndrew Turner 
498e03dd59SAndrew Turner extern int __sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp,
508e03dd59SAndrew Turner     void *newp, size_t newlen);
518e03dd59SAndrew Turner 
528e03dd59SAndrew Turner int _libc_arm_fpu_present;
538e03dd59SAndrew Turner static bool _libc_aapcs_initialized;
548e03dd59SAndrew Turner 
558e03dd59SAndrew Turner void	_libc_aapcs_init(void) __attribute__((__constructor__, __used__));
568e03dd59SAndrew Turner 
578e03dd59SAndrew Turner void
_libc_aapcs_init(void)588e03dd59SAndrew Turner _libc_aapcs_init(void)
598e03dd59SAndrew Turner {
608e03dd59SAndrew Turner 	int mib[2];
618e03dd59SAndrew Turner 	size_t len;
628e03dd59SAndrew Turner 
638e03dd59SAndrew Turner 	if (_libc_aapcs_initialized)
648e03dd59SAndrew Turner 		return;
658e03dd59SAndrew Turner 
668e03dd59SAndrew Turner 	mib[0] = CTL_HW;
678e03dd59SAndrew Turner 	mib[1] = HW_FLOATINGPT;
688e03dd59SAndrew Turner 
698e03dd59SAndrew Turner 	len = sizeof(_libc_arm_fpu_present);
708e03dd59SAndrew Turner 	if (__sysctl(mib, 2, &_libc_arm_fpu_present, &len, NULL, 0) == -1 ||
718e03dd59SAndrew Turner 	    len != sizeof(_libc_arm_fpu_present)) {
728e03dd59SAndrew Turner 		/* sysctl failed, assume no vfp */
738e03dd59SAndrew Turner 		_libc_arm_fpu_present = 0;
748e03dd59SAndrew Turner 	}
758e03dd59SAndrew Turner 
768e03dd59SAndrew Turner 	_libc_aapcs_initialized = true;
778e03dd59SAndrew Turner }
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