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/*
* Various assembly language/system dependent hacks that are required
* so that we can minimize the amount of platform specific code.
* Copyright (C) 2000-2004 by Erik Andersen <andersen@codepoet.org>
* Copyright (C) 2017 by Waldemar Brodkorb <wbx@uclibc-ng.org>
* Ported from GNU C Library
* Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
*/
/* Copyright (C) 1995-2016 Free Software Foundation, Inc.
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/>. */
/* Define this if the system uses RELOCA. */
#define ELF_USES_RELOCA
#include <elf.h>
#include <link.h>
/* Initialization sequence for the GOT. */
#define INIT_GOT(GOT_BASE,MODULE) \
{ \
GOT_BASE[2] = (unsigned long) _dl_linux_resolve; \
GOT_BASE[1] = (unsigned long) MODULE; \
}
/* Here we define the magic numbers that this dynamic loader should accept */
#define MAGIC1 EM_AARCH64
#undef MAGIC2
/* Used for error messages */
#define ELF_TARGET "aarch64"
struct elf_resolve;
unsigned long _dl_linux_resolver(struct elf_resolve * tpnt, int reloc_entry);
#define elf_machine_type_class(type) \
((((type) == R_AARCH64_JUMP_SLOT \
|| (type) == R_AARCH64_TLS_DTPMOD \
|| (type) == R_AARCH64_TLS_DTPREL \
|| (type) == R_AARCH64_TLS_TPREL \
|| (type) == R_AARCH64_TLSDESC) * ELF_RTYPE_CLASS_PLT) \
| (((type) == R_AARCH64_COPY) * ELF_RTYPE_CLASS_COPY))
/* Return the link-time address of _DYNAMIC. Conveniently, this is the
first element of the GOT. */
extern const ElfW(Addr) _GLOBAL_OFFSET_TABLE_[] attribute_hidden;
static __always_inline ElfW(Addr) __attribute__ ((unused))
elf_machine_dynamic (void)
{
return _GLOBAL_OFFSET_TABLE_[0];
}
/* Return the run-time load address of the shared object. */
static __always_inline ElfW(Addr) __attribute__ ((unused))
elf_machine_load_address (void)
{
/* To figure out the load address we use the definition that for any symbol:
dynamic_addr(symbol) = static_addr(symbol) + load_addr
The choice of symbol is arbitrary. The static address we obtain
by constructing a non GOT reference to the symbol, the dynamic
address of the symbol we compute using adrp/add to compute the
symbol's address relative to the PC.
This depends on 32/16bit relocations being resolved at link time
and that the static address fits in the 32/16 bits. */
ElfW(Addr) static_addr;
ElfW(Addr) dynamic_addr;
__asm__(" \n"
" adrp %1, _dl_start; \n"
" add %1, %1, #:lo12:_dl_start \n"
" ldr %w0, 1f \n"
" b 2f \n"
"1: \n"
" .word _dl_start \n"
"2: \n"
: "=r" (static_addr), "=r" (dynamic_addr));
return dynamic_addr - static_addr;
}
static __always_inline void
elf_machine_relative(Elf64_Addr load_off, const Elf64_Addr rel_addr,
Elf64_Word relative_count)
{
Elf64_Rela *rpnt = (Elf64_Rela*)rel_addr;
--rpnt;
do {
Elf64_Addr *const reloc_addr = (Elf64_Addr*)(load_off + (++rpnt)->r_offset);
*reloc_addr = load_off + rpnt->r_addend;
} while (--relative_count);
}
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