glibc/sysdeps/unix/sysv/linux/aarch64/dl-procinfo.h
Siddhesh Poyarekar 6c85cc2852 aarch64: Fix undefined behavior in _dl_procinfo
1 << 31 is undefined, so replace it with a cleaner check.  Also remove
magic numbers in comments.

	* sysdeps/unix/sysv/linux/aarch64/dl-procinfo.h: Remove
	mention of magic numbers in comments.
	(_dl_procinfo): Fix undefined behavior
2017-06-09 14:18:12 +05:30

87 lines
2.2 KiB
C

/* Processor capability information handling macros - aarch64 version.
Copyright (C) 2017 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#ifndef _DL_PROCINFO_H
#define _DL_PROCINFO_H 1
#include <sys/auxv.h>
#include <unistd.h>
#include <ldsodefs.h>
#include <sysdep.h>
/* We cannot provide a general printing function. */
static inline int
__attribute__ ((unused))
_dl_procinfo (unsigned int type, unsigned long int word)
{
/* This table should match the information from arch/arm64/kernel/cpuinfo.c
in the kernel sources. */
int i;
/* Fallback to unknown output mechanism. */
if (type == AT_HWCAP2)
return -1;
_dl_printf ("AT_HWCAP: ");
for (i = 0; i < 32; ++i)
if ((word >> i) & 1)
_dl_printf (" %s", GLRO(dl_aarch64_cap_flags)[i]);
_dl_printf ("\n");
return 0;
}
static inline const char *
__attribute__ ((unused))
_dl_hwcap_string (int idx)
{
return GLRO(dl_aarch64_cap_flags)[idx];
};
/* Number of HWCAP bits set. */
#define _DL_HWCAP_COUNT 13
/* Offset of the last bit allocated in HWCAP. */
#define _DL_HWCAP_LAST 12
/* HWCAP_CPUID should be available by default to influence IFUNC as well as
library search. */
#define HWCAP_IMPORTANT HWCAP_CPUID
static inline int
__attribute__ ((unused))
_dl_string_hwcap (const char *str)
{
for (int i = 0; i < _DL_HWCAP_COUNT; i++)
{
if (strcmp (str, _dl_hwcap_string (i)) == 0)
return i;
}
return -1;
};
/* There're no platforms to filter out. */
#define _DL_HWCAP_PLATFORM 0
#define _dl_string_platform(str) (-1)
#endif /* dl-procinfo.h */