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/* Pointer obfuscation implenentation. i386 version.
Copyright (C) 2005-2023 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
<https://www.gnu.org/licenses/>. */
#ifndef POINTER_GUARD_H
#define POINTER_GUARD_H
#include <tcb-offsets.h>
#if IS_IN (rtld)
/* We cannot use the thread descriptor because in ld.so we use setjmp
earlier than the descriptor is initialized. Using a global variable
is too complicated here since we have no PC-relative addressing mode. */
# include <sysdeps/generic/pointer_guard.h>
#else
# ifdef __ASSEMBLER__
# define PTR_MANGLE(reg) xorl %gs:POINTER_GUARD, reg; \
roll $9, reg
# define PTR_DEMANGLE(reg) rorl $9, reg; \
xorl %gs:POINTER_GUARD, reg
# else
# define PTR_MANGLE(var) asm ("xorl %%gs:%c2, %0\n" \
"roll $9, %0" \
: "=r" (var) \
: "0" (var), \
"i" (POINTER_GUARD))
# define PTR_DEMANGLE(var) asm ("rorl $9, %0\n" \
"xorl %%gs:%c2, %0" \
: "=r" (var) \
: "0" (var), \
"i" (POINTER_GUARD))
# endif
#endif
#endif /* POINTER_GUARD_H */
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