]> git.ipfire.org Git - thirdparty/gcc.git/blame - libitm/config/arm/hwcap.cc
Update copyright years.
[thirdparty/gcc.git] / libitm / config / arm / hwcap.cc
CommitLineData
a945c346 1/* Copyright (C) 2011-2024 Free Software Foundation, Inc.
aebac0ca
RH
2 Contributed by Richard Henderson <rth@redhat.com>.
3
4 This file is part of the GNU Transactional Memory Library (libitm).
5
6 Libitm is free software; you can redistribute it and/or modify it
7 under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
10
11 Libitm is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
13 FOR A PARTICULAR PURPOSE. See the GNU General Public License for
14 more details.
15
16 Under Section 7 of GPL version 3, you are granted additional
17 permissions described in the GCC Runtime Library Exception, version
18 3.1, as published by the Free Software Foundation.
19
20 You should have received a copy of the GNU General Public License and
21 a copy of the GCC Runtime Library Exception along with this program;
22 see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23 <http://www.gnu.org/licenses/>. */
24
25/* This file initializes GTM_hwcap in some os-specific way to indicate
26 what ISA extensions are present for ARM. */
27
28#include "libitm_i.h"
29#include "hwcap.h"
30
31/* Begin by defaulting to whatever options were given to the compiler. */
32int GTM_hwcap HIDDEN = 0
33#ifdef __VFP_FP__
34 | HWCAP_ARM_VFP
35#endif
36#ifdef __IWMMXT__
37 | HWCAP_ARM_IWMMXT
38#endif
39 ;
40
41#ifdef __linux__
42#include <unistd.h>
96ce40cb 43#include <fcntl.h>
aebac0ca
RH
44#include <elf.h>
45
46static void __attribute__((constructor))
47init_gtm_hwcap(void)
48{
49 int fd = open ("/proc/self/auxv", O_RDONLY);
50 if (fd < 0)
51 return;
52
53 Elf32_auxv_t pairs[512];
54 ssize_t rlen = read (fd, pairs, sizeof(pairs));
55 close (fd);
56 if (rlen < 0)
57 return;
58
59 size_t n = (size_t)rlen / sizeof(pairs[0]);
60 for (size_t i = 0; i < n; ++i)
61 if (pairs[i].a_type == AT_HWCAP)
62 {
63 GTM_hwcap = pairs[i].a_un.a_val;
64 return;
65 }
66}
67#endif