diff options
Diffstat (limited to 'lib/libc/arm/gen/arm_initfini.c')
-rw-r--r-- | lib/libc/arm/gen/arm_initfini.c | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/lib/libc/arm/gen/arm_initfini.c b/lib/libc/arm/gen/arm_initfini.c new file mode 100644 index 0000000..9def8c8 --- /dev/null +++ b/lib/libc/arm/gen/arm_initfini.c @@ -0,0 +1,78 @@ +/*- + * Copyright (c) 2013 The NetBSD Foundation, Inc. + * Copyright (c) 2013 Andrew Turner + * All rights reserved. + * + * This code is derived from software contributed to The NetBSD Foundation + * by Matt Thomas of 3am Software Foundry. + * + * 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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. + * + * Bases on NetBSD lib/libc/arch/arm/misc/arm_initfini.c + * $NetBSD: arm_initfini.c,v 1.2 2013/01/31 06:47:55 matt Exp $ + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +/* + * To properly implement setjmp/longjmp for the ARM AAPCS ABI, it has to be + * aware of whether there is a FPU is present or not. Regardless of whether + * the hard-float ABI is being used, setjmp needs to save D8-D15. But it can + * only do this if those instructions won't cause an exception. + */ + +#include <sys/param.h> +#include <sys/sysctl.h> + +#include <stdbool.h> +#include <stddef.h> + +extern int __sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp, + void *newp, size_t newlen); + +int _libc_arm_fpu_present; +static bool _libc_aapcs_initialized; + +void _libc_aapcs_init(void) __attribute__((__constructor__, __used__)); + +void +_libc_aapcs_init(void) +{ + int mib[2]; + size_t len; + + if (_libc_aapcs_initialized) + return; + + mib[0] = CTL_HW; + mib[1] = HW_FLOATINGPT; + + len = sizeof(_libc_arm_fpu_present); + if (__sysctl(mib, 2, &_libc_arm_fpu_present, &len, NULL, 0) == -1 || + len != sizeof(_libc_arm_fpu_present)) { + /* sysctl failed, assume no vfp */ + _libc_arm_fpu_present = 0; + } + + _libc_aapcs_initialized = true; +} |