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binutils-gdb/gold/aarch64.cc
Alan Modra 91a65d2fe8 [GOLD] Relocate::relocate() params 
Some linker code editing needs to change multiple insns.  In some
cases multiple relocations are involved and it is not sufficient to
make the changes independently as relocations are processed, because
doing so might lead to a partial edit.  So in order to safely edit we
need all the relocations available in relocate().  Also, to emit
edited relocs corresponding to the edited code sequence we need some
way to pass information from relocate() to relocate_relocs(),
particularly if the edit depends on insns.  We can't modify input
relocs in relocate() as they are mmapped PROT_READ, nor it is
particularly clean to write relocs to the output at that stage.  So
add a Relocatable_relocs* field to relinfo to mark edited relocs.

Given that relocate is passed the raw reloc pointer, it makes sense to
remove the rel/rela parameter and r_type too.  However, that means the
mips relocate() needs to know whether SHT_REL or SHT_RELA relocs are
being processed.  So add a rel_type for mips, which also has the
benefit of removing relocate() overloading there.

This patch adds the infrastructure without making use of it.

Note that relinfo->rr will be NULL if not outputting relocations.

	* object.h (struct Relocate_info): Add "rr".
	* reloc.h (Relocatable_relocs::set_strategy): New accessor.
	* reloc.cc (Sized_relobj_file::do_relocate_sections): Init
	relinfo.rr for relocate_section and relocate_relocs.
	* powerpc.cc (relocate): Add rel_type and preloc parameters.
	Delete rela and r_type params, instead recalculate these from
	preloc.
	(relocate_relocs): Delete Relocatable_relocs* param, instead
	use relinfo->rr.
	* aarch64.cc: Likewise.
	* arm.cc: Likewise.
	* i386.cc: Likewise.
	* mips.cc: Likewise.
	* s390.cc: Likewise.
	* sparc.cc: Likewise.
	* target.h: Likewise.
	* tilegx.cc: Likewise.
	* x86_64.cc: Likewise.
	* testsuite/testfile.cc: Likewise.
	* target-reloc.h (relocate_section): Adjust to suit.
	(apply_relocation, relocate_relocs): Likewise.
2015-12-09 10:36:43 +10:30

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// aarch64.cc -- aarch64 target support for gold.
// Copyright (C) 2014-2015 Free Software Foundation, Inc.
// Written by Jing Yu <jingyu@google.com> and Han Shen <shenhan@google.com>.
// This file is part of gold.
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 3 of the License, or
// (at your option) any later version.
// This program 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 General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
// MA 02110-1301, USA.
#include "gold.h"
#include <cstring>
#include <map>
#include <set>
#include "elfcpp.h"
#include "dwarf.h"
#include "parameters.h"
#include "reloc.h"
#include "aarch64.h"
#include "object.h"
#include "symtab.h"
#include "layout.h"
#include "output.h"
#include "copy-relocs.h"
#include "target.h"
#include "target-reloc.h"
#include "target-select.h"
#include "tls.h"
#include "freebsd.h"
#include "nacl.h"
#include "gc.h"
#include "icf.h"
#include "aarch64-reloc-property.h"
// The first three .got.plt entries are reserved.
const int32_t AARCH64_GOTPLT_RESERVE_COUNT = 3;
namespace
{
using namespace gold;
template<int size, bool big_endian>
class Output_data_plt_aarch64;
template<int size, bool big_endian>
class Output_data_plt_aarch64_standard;
template<int size, bool big_endian>
class Target_aarch64;
template<int size, bool big_endian>
class AArch64_relocate_functions;
// Utility class dealing with insns. This is ported from macros in
// bfd/elfnn-aarch64.cc, but wrapped inside a class as static members. This
// class is used in erratum sequence scanning.
template<bool big_endian>
class AArch64_insn_utilities
{
public:
typedef typename elfcpp::Swap<32, big_endian>::Valtype Insntype;
static const int BYTES_PER_INSN;
// Zero register encoding - 31.
static const unsigned int AARCH64_ZR;
static unsigned int
aarch64_bit(Insntype insn, int pos)
{ return ((1 << pos) & insn) >> pos; }
static unsigned int
aarch64_bits(Insntype insn, int pos, int l)
{ return (insn >> pos) & ((1 << l) - 1); }
// Get the encoding field "op31" of 3-source data processing insns. "op31" is
// the name defined in armv8 insn manual C3.5.9.
static unsigned int
aarch64_op31(Insntype insn)
{ return aarch64_bits(insn, 21, 3); }
// Get the encoding field "ra" of 3-source data processing insns. "ra" is the
// third source register. See armv8 insn manual C3.5.9.
static unsigned int
aarch64_ra(Insntype insn)
{ return aarch64_bits(insn, 10, 5); }
static bool
is_adr(const Insntype insn)
{ return (insn & 0x9F000000) == 0x10000000; }
static bool
is_adrp(const Insntype insn)
{ return (insn & 0x9F000000) == 0x90000000; }
static unsigned int
aarch64_rm(const Insntype insn)
{ return aarch64_bits(insn, 16, 5); }
static unsigned int
aarch64_rn(const Insntype insn)
{ return aarch64_bits(insn, 5, 5); }
static unsigned int
aarch64_rd(const Insntype insn)
{ return aarch64_bits(insn, 0, 5); }
static unsigned int
aarch64_rt(const Insntype insn)
{ return aarch64_bits(insn, 0, 5); }
static unsigned int
aarch64_rt2(const Insntype insn)
{ return aarch64_bits(insn, 10, 5); }
// Encode imm21 into adr. Signed imm21 is in the range of [-1M, 1M).
static Insntype
aarch64_adr_encode_imm(Insntype adr, int imm21)
{
gold_assert(is_adr(adr));
gold_assert(-(1 << 20) <= imm21 && imm21 < (1 << 20));
const int mask19 = (1 << 19) - 1;
const int mask2 = 3;
adr &= ~((mask19 << 5) | (mask2 << 29));
adr |= ((imm21 & mask2) << 29) | (((imm21 >> 2) & mask19) << 5);
return adr;
}
// Retrieve encoded adrp 33-bit signed imm value. This value is obtained by
// 21-bit signed imm encoded in the insn multiplied by 4k (page size) and
// 64-bit sign-extended, resulting in [-4G, 4G) with 12-lsb being 0.
static int64_t
aarch64_adrp_decode_imm(const Insntype adrp)
{
const int mask19 = (1 << 19) - 1;
const int mask2 = 3;
gold_assert(is_adrp(adrp));
// 21-bit imm encoded in adrp.
uint64_t imm = ((adrp >> 29) & mask2) | (((adrp >> 5) & mask19) << 2);
// Retrieve msb of 21-bit-signed imm for sign extension.
uint64_t msbt = (imm >> 20) & 1;
// Real value is imm multipled by 4k. Value now has 33-bit information.
int64_t value = imm << 12;
// Sign extend to 64-bit by repeating msbt 31 (64-33) times and merge it
// with value.
return ((((uint64_t)(1) << 32) - msbt) << 33) | value;
}
static bool
aarch64_b(const Insntype insn)
{ return (insn & 0xFC000000) == 0x14000000; }
static bool
aarch64_bl(const Insntype insn)
{ return (insn & 0xFC000000) == 0x94000000; }
static bool
aarch64_blr(const Insntype insn)
{ return (insn & 0xFFFFFC1F) == 0xD63F0000; }
static bool
aarch64_br(const Insntype insn)
{ return (insn & 0xFFFFFC1F) == 0xD61F0000; }
// All ld/st ops. See C4-182 of the ARM ARM. The encoding space for
// LD_PCREL, LDST_RO, LDST_UI and LDST_UIMM cover prefetch ops.
static bool
aarch64_ld(Insntype insn) { return aarch64_bit(insn, 22) == 1; }
static bool
aarch64_ldst(Insntype insn)
{ return (insn & 0x0a000000) == 0x08000000; }
static bool
aarch64_ldst_ex(Insntype insn)
{ return (insn & 0x3f000000) == 0x08000000; }
static bool
aarch64_ldst_pcrel(Insntype insn)
{ return (insn & 0x3b000000) == 0x18000000; }
static bool
aarch64_ldst_nap(Insntype insn)
{ return (insn & 0x3b800000) == 0x28000000; }
static bool
aarch64_ldstp_pi(Insntype insn)
{ return (insn & 0x3b800000) == 0x28800000; }
static bool
aarch64_ldstp_o(Insntype insn)
{ return (insn & 0x3b800000) == 0x29000000; }
static bool
aarch64_ldstp_pre(Insntype insn)
{ return (insn & 0x3b800000) == 0x29800000; }
static bool
aarch64_ldst_ui(Insntype insn)
{ return (insn & 0x3b200c00) == 0x38000000; }
static bool
aarch64_ldst_piimm(Insntype insn)
{ return (insn & 0x3b200c00) == 0x38000400; }
static bool
aarch64_ldst_u(Insntype insn)
{ return (insn & 0x3b200c00) == 0x38000800; }
static bool
aarch64_ldst_preimm(Insntype insn)
{ return (insn & 0x3b200c00) == 0x38000c00; }
static bool
aarch64_ldst_ro(Insntype insn)
{ return (insn & 0x3b200c00) == 0x38200800; }
static bool
aarch64_ldst_uimm(Insntype insn)
{ return (insn & 0x3b000000) == 0x39000000; }
static bool
aarch64_ldst_simd_m(Insntype insn)
{ return (insn & 0xbfbf0000) == 0x0c000000; }
static bool
aarch64_ldst_simd_m_pi(Insntype insn)
{ return (insn & 0xbfa00000) == 0x0c800000; }
static bool
aarch64_ldst_simd_s(Insntype insn)
{ return (insn & 0xbf9f0000) == 0x0d000000; }
static bool
aarch64_ldst_simd_s_pi(Insntype insn)
{ return (insn & 0xbf800000) == 0x0d800000; }
// Classify an INSN if it is indeed a load/store. Return true if INSN is a
// LD/ST instruction otherwise return false. For scalar LD/ST instructions
// PAIR is FALSE, RT is returned and RT2 is set equal to RT. For LD/ST pair
// instructions PAIR is TRUE, RT and RT2 are returned.
static bool
aarch64_mem_op_p(Insntype insn, unsigned int *rt, unsigned int *rt2,
bool *pair, bool *load)
{
uint32_t opcode;
unsigned int r;
uint32_t opc = 0;
uint32_t v = 0;
uint32_t opc_v = 0;
/* Bail out quickly if INSN doesn't fall into the the load-store
encoding space. */
if (!aarch64_ldst (insn))
return false;
*pair = false;
*load = false;
if (aarch64_ldst_ex (insn))
{
*rt = aarch64_rt (insn);
*rt2 = *rt;
if (aarch64_bit (insn, 21) == 1)
{
*pair = true;
*rt2 = aarch64_rt2 (insn);
}
*load = aarch64_ld (insn);
return true;
}
else if (aarch64_ldst_nap (insn)
|| aarch64_ldstp_pi (insn)
|| aarch64_ldstp_o (insn)
|| aarch64_ldstp_pre (insn))
{
*pair = true;
*rt = aarch64_rt (insn);
*rt2 = aarch64_rt2 (insn);
*load = aarch64_ld (insn);
return true;
}
else if (aarch64_ldst_pcrel (insn)
|| aarch64_ldst_ui (insn)
|| aarch64_ldst_piimm (insn)
|| aarch64_ldst_u (insn)
|| aarch64_ldst_preimm (insn)
|| aarch64_ldst_ro (insn)
|| aarch64_ldst_uimm (insn))
{
*rt = aarch64_rt (insn);
*rt2 = *rt;
if (aarch64_ldst_pcrel (insn))
*load = true;
opc = aarch64_bits (insn, 22, 2);
v = aarch64_bit (insn, 26);
opc_v = opc | (v << 2);
*load = (opc_v == 1 || opc_v == 2 || opc_v == 3
|| opc_v == 5 || opc_v == 7);
return true;
}
else if (aarch64_ldst_simd_m (insn)
|| aarch64_ldst_simd_m_pi (insn))
{
*rt = aarch64_rt (insn);
*load = aarch64_bit (insn, 22);
opcode = (insn >> 12) & 0xf;
switch (opcode)
{
case 0:
case 2:
*rt2 = *rt + 3;
break;
case 4:
case 6:
*rt2 = *rt + 2;
break;
case 7:
*rt2 = *rt;
break;
case 8:
case 10:
*rt2 = *rt + 1;
break;
default:
return false;
}
return true;
}
else if (aarch64_ldst_simd_s (insn)
|| aarch64_ldst_simd_s_pi (insn))
{
*rt = aarch64_rt (insn);
r = (insn >> 21) & 1;
*load = aarch64_bit (insn, 22);
opcode = (insn >> 13) & 0x7;
switch (opcode)
{
case 0:
case 2:
case 4:
*rt2 = *rt + r;
break;
case 1:
case 3:
case 5:
*rt2 = *rt + (r == 0 ? 2 : 3);
break;
case 6:
*rt2 = *rt + r;
break;
case 7:
*rt2 = *rt + (r == 0 ? 2 : 3);
break;
default:
return false;
}
return true;
}
return false;
} // End of "aarch64_mem_op_p".
// Return true if INSN is mac insn.
static bool
aarch64_mac(Insntype insn)
{ return (insn & 0xff000000) == 0x9b000000; }
// Return true if INSN is multiply-accumulate.
// (This is similar to implementaton in elfnn-aarch64.c.)
static bool
aarch64_mlxl(Insntype insn)
{
uint32_t op31 = aarch64_op31(insn);
if (aarch64_mac(insn)
&& (op31 == 0 || op31 == 1 || op31 == 5)
/* Exclude MUL instructions which are encoded as a multiple-accumulate
with RA = XZR. */
&& aarch64_ra(insn) != AARCH64_ZR)
{
return true;
}
return false;
}
}; // End of "AArch64_insn_utilities".
// Insn length in byte.
template<bool big_endian>
const int AArch64_insn_utilities<big_endian>::BYTES_PER_INSN = 4;
// Zero register encoding - 31.
template<bool big_endian>
const unsigned int AArch64_insn_utilities<big_endian>::AARCH64_ZR = 0x1f;
// Output_data_got_aarch64 class.
template<int size, bool big_endian>
class Output_data_got_aarch64 : public Output_data_got<size, big_endian>
{
public:
typedef typename elfcpp::Elf_types<size>::Elf_Addr Valtype;
Output_data_got_aarch64(Symbol_table* symtab, Layout* layout)
: Output_data_got<size, big_endian>(),
symbol_table_(symtab), layout_(layout)
{ }
// Add a static entry for the GOT entry at OFFSET. GSYM is a global
// symbol and R_TYPE is the code of a dynamic relocation that needs to be
// applied in a static link.
void
add_static_reloc(unsigned int got_offset, unsigned int r_type, Symbol* gsym)
{ this->static_relocs_.push_back(Static_reloc(got_offset, r_type, gsym)); }
// Add a static reloc for the GOT entry at OFFSET. RELOBJ is an object
// defining a local symbol with INDEX. R_TYPE is the code of a dynamic
// relocation that needs to be applied in a static link.
void
add_static_reloc(unsigned int got_offset, unsigned int r_type,
Sized_relobj_file<size, big_endian>* relobj,
unsigned int index)
{
this->static_relocs_.push_back(Static_reloc(got_offset, r_type, relobj,
index));
}
protected:
// Write out the GOT table.
void
do_write(Output_file* of) {
// The first entry in the GOT is the address of the .dynamic section.
gold_assert(this->data_size() >= size / 8);
Output_section* dynamic = this->layout_->dynamic_section();
Valtype dynamic_addr = dynamic == NULL ? 0 : dynamic->address();
this->replace_constant(0, dynamic_addr);
Output_data_got<size, big_endian>::do_write(of);
// Handling static relocs
if (this->static_relocs_.empty())
return;
typedef typename elfcpp::Elf_types<size>::Elf_Addr AArch64_address;
gold_assert(parameters->doing_static_link());
const off_t offset = this->offset();
const section_size_type oview_size =
convert_to_section_size_type(this->data_size());
unsigned char* const oview = of->get_output_view(offset, oview_size);
Output_segment* tls_segment = this->layout_->tls_segment();
gold_assert(tls_segment != NULL);
AArch64_address aligned_tcb_address =
align_address(Target_aarch64<size, big_endian>::TCB_SIZE,
tls_segment->maximum_alignment());
for (size_t i = 0; i < this->static_relocs_.size(); ++i)
{
Static_reloc& reloc(this->static_relocs_[i]);
AArch64_address value;
if (!reloc.symbol_is_global())
{
Sized_relobj_file<size, big_endian>* object = reloc.relobj();
const Symbol_value<size>* psymval =
reloc.relobj()->local_symbol(reloc.index());
// We are doing static linking. Issue an error and skip this
// relocation if the symbol is undefined or in a discarded_section.
bool is_ordinary;
unsigned int shndx = psymval->input_shndx(&is_ordinary);
if ((shndx == elfcpp::SHN_UNDEF)
|| (is_ordinary
&& shndx != elfcpp::SHN_UNDEF
&& !object->is_section_included(shndx)
&& !this->symbol_table_->is_section_folded(object, shndx)))
{
gold_error(_("undefined or discarded local symbol %u from "
" object %s in GOT"),
reloc.index(), reloc.relobj()->name().c_str());
continue;
}
value = psymval->value(object, 0);
}
else
{
const Symbol* gsym = reloc.symbol();
gold_assert(gsym != NULL);
if (gsym->is_forwarder())
gsym = this->symbol_table_->resolve_forwards(gsym);
// We are doing static linking. Issue an error and skip this
// relocation if the symbol is undefined or in a discarded_section
// unless it is a weakly_undefined symbol.
if ((gsym->is_defined_in_discarded_section()
|| gsym->is_undefined())
&& !gsym->is_weak_undefined())
{
gold_error(_("undefined or discarded symbol %s in GOT"),
gsym->name());
continue;
}
if (!gsym->is_weak_undefined())
{
const Sized_symbol<size>* sym =
static_cast<const Sized_symbol<size>*>(gsym);
value = sym->value();
}
else
value = 0;
}
unsigned got_offset = reloc.got_offset();
gold_assert(got_offset < oview_size);
typedef typename elfcpp::Swap<size, big_endian>::Valtype Valtype;
Valtype* wv = reinterpret_cast<Valtype*>(oview + got_offset);
Valtype x;
switch (reloc.r_type())
{
case elfcpp::R_AARCH64_TLS_DTPREL64:
x = value;
break;
case elfcpp::R_AARCH64_TLS_TPREL64:
x = value + aligned_tcb_address;
break;
default:
gold_unreachable();
}
elfcpp::Swap<size, big_endian>::writeval(wv, x);
}
of->write_output_view(offset, oview_size, oview);
}
private:
// Symbol table of the output object.
Symbol_table* symbol_table_;
// A pointer to the Layout class, so that we can find the .dynamic
// section when we write out the GOT section.
Layout* layout_;
// This class represent dynamic relocations that need to be applied by
// gold because we are using TLS relocations in a static link.
class Static_reloc
{
public:
Static_reloc(unsigned int got_offset, unsigned int r_type, Symbol* gsym)
: got_offset_(got_offset), r_type_(r_type), symbol_is_global_(true)
{ this->u_.global.symbol = gsym; }
Static_reloc(unsigned int got_offset, unsigned int r_type,
Sized_relobj_file<size, big_endian>* relobj, unsigned int index)
: got_offset_(got_offset), r_type_(r_type), symbol_is_global_(false)
{
this->u_.local.relobj = relobj;
this->u_.local.index = index;
}
// Return the GOT offset.
unsigned int
got_offset() const
{ return this->got_offset_; }
// Relocation type.
unsigned int
r_type() const
{ return this->r_type_; }
// Whether the symbol is global or not.
bool
symbol_is_global() const
{ return this->symbol_is_global_; }
// For a relocation against a global symbol, the global symbol.
Symbol*
symbol() const
{
gold_assert(this->symbol_is_global_);
return this->u_.global.symbol;
}
// For a relocation against a local symbol, the defining object.
Sized_relobj_file<size, big_endian>*
relobj() const
{
gold_assert(!this->symbol_is_global_);
return this->u_.local.relobj;
}
// For a relocation against a local symbol, the local symbol index.
unsigned int
index() const
{
gold_assert(!this->symbol_is_global_);
return this->u_.local.index;
}
private:
// GOT offset of the entry to which this relocation is applied.
unsigned int got_offset_;
// Type of relocation.
unsigned int r_type_;
// Whether this relocation is against a global symbol.
bool symbol_is_global_;
// A global or local symbol.
union
{
struct
{
// For a global symbol, the symbol itself.
Symbol* symbol;
} global;
struct
{
// For a local symbol, the object defining the symbol.
Sized_relobj_file<size, big_endian>* relobj;
// For a local symbol, the symbol index.
unsigned int index;
} local;
} u_;
}; // End of inner class Static_reloc
std::vector<Static_reloc> static_relocs_;
}; // End of Output_data_got_aarch64
template<int size, bool big_endian>
class AArch64_input_section;
template<int size, bool big_endian>
class AArch64_output_section;
template<int size, bool big_endian>
class AArch64_relobj;
// Stub type enum constants.
enum
{
ST_NONE = 0,
// Using adrp/add pair, 4 insns (including alignment) without mem access,
// the fastest stub. This has a limited jump distance, which is tested by
// aarch64_valid_for_adrp_p.
ST_ADRP_BRANCH = 1,
// Using ldr-absolute-address/br-register, 4 insns with 1 mem access,
// unlimited in jump distance.
ST_LONG_BRANCH_ABS = 2,
// Using ldr/calculate-pcrel/jump, 8 insns (including alignment) with 1
// mem access, slowest one. Only used in position independent executables.
ST_LONG_BRANCH_PCREL = 3,
// Stub for erratum 843419 handling.
ST_E_843419 = 4,
// Stub for erratum 835769 handling.
ST_E_835769 = 5,
// Number of total stub types.
ST_NUMBER = 6
};
// Struct that wraps insns for a particular stub. All stub templates are
// created/initialized as constants by Stub_template_repertoire.
template<bool big_endian>
struct Stub_template
{
const typename AArch64_insn_utilities<big_endian>::Insntype* insns;
const int insn_num;
};
// Simple singleton class that creates/initializes/stores all types of stub
// templates.
template<bool big_endian>
class Stub_template_repertoire
{
public:
typedef typename AArch64_insn_utilities<big_endian>::Insntype Insntype;
// Single static method to get stub template for a given stub type.
static const Stub_template<big_endian>*
get_stub_template(int type)
{
static Stub_template_repertoire<big_endian> singleton;
return singleton.stub_templates_[type];
}
private:
// Constructor - creates/initializes all stub templates.
Stub_template_repertoire();
~Stub_template_repertoire()
{ }
// Disallowing copy ctor and copy assignment operator.
Stub_template_repertoire(Stub_template_repertoire&);
Stub_template_repertoire& operator=(Stub_template_repertoire&);
// Data that stores all insn templates.
const Stub_template<big_endian>* stub_templates_[ST_NUMBER];
}; // End of "class Stub_template_repertoire".
// Constructor - creates/initilizes all stub templates.
template<bool big_endian>
Stub_template_repertoire<big_endian>::Stub_template_repertoire()
{
// Insn array definitions.
const static Insntype ST_NONE_INSNS[] = {};
const static Insntype ST_ADRP_BRANCH_INSNS[] =
{
0x90000010, /* adrp ip0, X */
/* ADR_PREL_PG_HI21(X) */
0x91000210, /* add ip0, ip0, :lo12:X */
/* ADD_ABS_LO12_NC(X) */
0xd61f0200, /* br ip0 */
0x00000000, /* alignment padding */
};
const static Insntype ST_LONG_BRANCH_ABS_INSNS[] =
{
0x58000050, /* ldr ip0, 0x8 */
0xd61f0200, /* br ip0 */
0x00000000, /* address field */
0x00000000, /* address fields */
};
const static Insntype ST_LONG_BRANCH_PCREL_INSNS[] =
{
0x58000090, /* ldr ip0, 0x10 */
0x10000011, /* adr ip1, #0 */
0x8b110210, /* add ip0, ip0, ip1 */
0xd61f0200, /* br ip0 */
0x00000000, /* address field */
0x00000000, /* address field */
0x00000000, /* alignment padding */
0x00000000, /* alignment padding */
};
const static Insntype ST_E_843419_INSNS[] =
{
0x00000000, /* Placeholder for erratum insn. */
0x14000000, /* b <label> */
};
// ST_E_835769 has the same stub template as ST_E_843419.
const static Insntype* ST_E_835769_INSNS = ST_E_843419_INSNS;
#define install_insn_template(T) \
const static Stub_template<big_endian> template_##T = { \
T##_INSNS, sizeof(T##_INSNS) / sizeof(T##_INSNS[0]) }; \
this->stub_templates_[T] = &template_##T
install_insn_template(ST_NONE);
install_insn_template(ST_ADRP_BRANCH);
install_insn_template(ST_LONG_BRANCH_ABS);
install_insn_template(ST_LONG_BRANCH_PCREL);
install_insn_template(ST_E_843419);
install_insn_template(ST_E_835769);
#undef install_insn_template
}
// Base class for stubs.
template<int size, bool big_endian>
class Stub_base
{
public:
typedef typename elfcpp::Elf_types<size>::Elf_Addr AArch64_address;
typedef typename AArch64_insn_utilities<big_endian>::Insntype Insntype;
static const AArch64_address invalid_address =
static_cast<AArch64_address>(-1);
static const section_offset_type invalid_offset =
static_cast<section_offset_type>(-1);
Stub_base(int type)
: destination_address_(invalid_address),
offset_(invalid_offset),
type_(type)
{}
~Stub_base()
{}
// Get stub type.
int
type() const
{ return this->type_; }
// Get stub template that provides stub insn information.
const Stub_template<big_endian>*
stub_template() const
{
return Stub_template_repertoire<big_endian>::
get_stub_template(this->type());
}
// Get destination address.
AArch64_address
destination_address() const
{
gold_assert(this->destination_address_ != this->invalid_address);
return this->destination_address_;
}
// Set destination address.
void
set_destination_address(AArch64_address address)
{
gold_assert(address != this->invalid_address);
this->destination_address_ = address;
}
// Reset the destination address.
void
reset_destination_address()
{ this->destination_address_ = this->invalid_address; }
// Get offset of code stub. For Reloc_stub, it is the offset from the
// beginning of its containing stub table; for Erratum_stub, it is the offset
// from the end of reloc_stubs.
section_offset_type
offset() const
{
gold_assert(this->offset_ != this->invalid_offset);
return this->offset_;
}
// Set stub offset.
void
set_offset(section_offset_type offset)
{ this->offset_ = offset; }
// Return the stub insn.
const Insntype*
insns() const
{ return this->stub_template()->insns; }
// Return num of stub insns.
unsigned int
insn_num() const
{ return this->stub_template()->insn_num; }
// Get size of the stub.
int
stub_size() const
{
return this->insn_num() *
AArch64_insn_utilities<big_endian>::BYTES_PER_INSN;
}
// Write stub to output file.
void
write(unsigned char* view, section_size_type view_size)
{ this->do_write(view, view_size); }
protected:
// Abstract method to be implemented by sub-classes.
virtual void
do_write(unsigned char*, section_size_type) = 0;
private:
// The last insn of a stub is a jump to destination insn. This field records
// the destination address.
AArch64_address destination_address_;
// The stub offset. Note this has difference interpretations between an
// Reloc_stub and an Erratum_stub. For Reloc_stub this is the offset from the
// beginning of the containing stub_table, whereas for Erratum_stub, this is
// the offset from the end of reloc_stubs.
section_offset_type offset_;
// Stub type.
const int type_;
}; // End of "Stub_base".
// Erratum stub class. An erratum stub differs from a reloc stub in that for
// each erratum occurrence, we generate an erratum stub. We never share erratum
// stubs, whereas for reloc stubs, different branches insns share a single reloc
// stub as long as the branch targets are the same. (More to the point, reloc
// stubs can be shared because they're used to reach a specific target, whereas
// erratum stubs branch back to the original control flow.)
template<int size, bool big_endian>
class Erratum_stub : public Stub_base<size, big_endian>
{
public:
typedef AArch64_relobj<size, big_endian> The_aarch64_relobj;
typedef typename elfcpp::Elf_types<size>::Elf_Addr AArch64_address;
typedef AArch64_insn_utilities<big_endian> Insn_utilities;
typedef typename AArch64_insn_utilities<big_endian>::Insntype Insntype;
static const int STUB_ADDR_ALIGN;
static const Insntype invalid_insn = static_cast<Insntype>(-1);
Erratum_stub(The_aarch64_relobj* relobj, int type,
unsigned shndx, unsigned int sh_offset)
: Stub_base<size, big_endian>(type), relobj_(relobj),
shndx_(shndx), sh_offset_(sh_offset),
erratum_insn_(invalid_insn),
erratum_address_(this->invalid_address)
{}
~Erratum_stub() {}
// Return the object that contains the erratum.
The_aarch64_relobj*
relobj()
{ return this->relobj_; }
// Get section index of the erratum.
unsigned int
shndx() const
{ return this->shndx_; }
// Get section offset of the erratum.
unsigned int
sh_offset() const
{ return this->sh_offset_; }
// Get the erratum insn. This is the insn located at erratum_insn_address.
Insntype
erratum_insn() const
{
gold_assert(this->erratum_insn_ != this->invalid_insn);
return this->erratum_insn_;
}
// Set the insn that the erratum happens to.
void
set_erratum_insn(Insntype insn)
{ this->erratum_insn_ = insn; }
// For 843419, the erratum insn is ld/st xt, [xn, #uimm], which may be a
// relocation spot, in this case, the erratum_insn_ recorded at scanning phase
// is no longer the one we want to write out to the stub, update erratum_insn_
// with relocated version. Also note that in this case xn must not be "PC", so
// it is safe to move the erratum insn from the origin place to the stub. For
// 835769, the erratum insn is multiply-accumulate insn, which could not be a
// relocation spot (assertion added though).
void
update_erratum_insn(Insntype insn)
{
gold_assert(this->erratum_insn_ != this->invalid_insn);
switch (this->type())
{
case ST_E_843419:
gold_assert(Insn_utilities::aarch64_ldst_uimm(insn));
gold_assert(Insn_utilities::aarch64_ldst_uimm(this->erratum_insn()));
gold_assert(Insn_utilities::aarch64_rd(insn) ==
Insn_utilities::aarch64_rd(this->erratum_insn()));
gold_assert(Insn_utilities::aarch64_rn(insn) ==
Insn_utilities::aarch64_rn(this->erratum_insn()));
// Update plain ld/st insn with relocated insn.
this->erratum_insn_ = insn;
break;
case ST_E_835769:
gold_assert(insn == this->erratum_insn());
break;
default:
gold_unreachable();
}
}
// Return the address where an erratum must be done.
AArch64_address
erratum_address() const
{
gold_assert(this->erratum_address_ != this->invalid_address);
return this->erratum_address_;
}
// Set the address where an erratum must be done.
void
set_erratum_address(AArch64_address addr)
{ this->erratum_address_ = addr; }
// Comparator used to group Erratum_stubs in a set by (obj, shndx,
// sh_offset). We do not include 'type' in the calculation, becuase there is
// at most one stub type at (obj, shndx, sh_offset).
bool
operator<(const Erratum_stub<size, big_endian>& k) const
{
if (this == &k)
return false;
// We group stubs by relobj.
if (this->relobj_ != k.relobj_)
return this->relobj_ < k.relobj_;
// Then by section index.
if (this->shndx_ != k.shndx_)
return this->shndx_ < k.shndx_;
// Lastly by section offset.
return this->sh_offset_ < k.sh_offset_;
}
protected:
virtual void
do_write(unsigned char*, section_size_type);
private:
// The object that needs to be fixed.
The_aarch64_relobj* relobj_;
// The shndx in the object that needs to be fixed.
const unsigned int shndx_;
// The section offset in the obejct that needs to be fixed.
const unsigned int sh_offset_;
// The insn to be fixed.
Insntype erratum_insn_;
// The address of the above insn.
AArch64_address erratum_address_;
}; // End of "Erratum_stub".
// Erratum sub class to wrap additional info needed by 843419. In fixing this
// erratum, we may choose to replace 'adrp' with 'adr', in this case, we need
// adrp's code position (two or three insns before erratum insn itself).
template<int size, bool big_endian>
class E843419_stub : public Erratum_stub<size, big_endian>
{
public:
typedef typename AArch64_insn_utilities<big_endian>::Insntype Insntype;
E843419_stub(AArch64_relobj<size, big_endian>* relobj,
unsigned int shndx, unsigned int sh_offset,
unsigned int adrp_sh_offset)
: Erratum_stub<size, big_endian>(relobj, ST_E_843419, shndx, sh_offset),
adrp_sh_offset_(adrp_sh_offset)
{}
unsigned int
adrp_sh_offset() const
{ return this->adrp_sh_offset_; }
private:
// Section offset of "adrp". (We do not need a "adrp_shndx_" field, because we
// can can obtain it from its parent.)
const unsigned int adrp_sh_offset_;
};
template<int size, bool big_endian>
const int Erratum_stub<size, big_endian>::STUB_ADDR_ALIGN = 4;
// Comparator used in set definition.
template<int size, bool big_endian>
struct Erratum_stub_less
{
bool
operator()(const Erratum_stub<size, big_endian>* s1,
const Erratum_stub<size, big_endian>* s2) const
{ return *s1 < *s2; }
};
// Erratum_stub implementation for writing stub to output file.
template<int size, bool big_endian>
void
Erratum_stub<size, big_endian>::do_write(unsigned char* view, section_size_type)
{
typedef typename elfcpp::Swap<32, big_endian>::Valtype Insntype;
const Insntype* insns = this->insns();
uint32_t num_insns = this->insn_num();
Insntype* ip = reinterpret_cast<Insntype*>(view);
// For current implemented erratum 843419 and 835769, the first insn in the
// stub is always a copy of the problematic insn (in 843419, the mem access
// insn, in 835769, the mac insn), followed by a jump-back.
elfcpp::Swap<32, big_endian>::writeval(ip, this->erratum_insn());
for (uint32_t i = 1; i < num_insns; ++i)
elfcpp::Swap<32, big_endian>::writeval(ip + i, insns[i]);
}
// Reloc stub class.
template<int size, bool big_endian>
class Reloc_stub : public Stub_base<size, big_endian>
{
public:
typedef Reloc_stub<size, big_endian> This;
typedef typename elfcpp::Elf_types<size>::Elf_Addr AArch64_address;
// Branch range. This is used to calculate the section group size, as well as
// determine whether a stub is needed.
static const int MAX_BRANCH_OFFSET = ((1 << 25) - 1) << 2;
static const int MIN_BRANCH_OFFSET = -((1 << 25) << 2);
// Constant used to determine if an offset fits in the adrp instruction
// encoding.
static const int MAX_ADRP_IMM = (1 << 20) - 1;
static const int MIN_ADRP_IMM = -(1 << 20);
static const int BYTES_PER_INSN = 4;
static const int STUB_ADDR_ALIGN;
// Determine whether the offset fits in the jump/branch instruction.
static bool
aarch64_valid_branch_offset_p(int64_t offset)
{ return offset >= MIN_BRANCH_OFFSET && offset <= MAX_BRANCH_OFFSET; }
// Determine whether the offset fits in the adrp immediate field.
static bool
aarch64_valid_for_adrp_p(AArch64_address location, AArch64_address dest)
{
typedef AArch64_relocate_functions<size, big_endian> Reloc;
int64_t adrp_imm = (Reloc::Page(dest) - Reloc::Page(location)) >> 12;
return adrp_imm >= MIN_ADRP_IMM && adrp_imm <= MAX_ADRP_IMM;
}
// Determine the stub type for a certain relocation or ST_NONE, if no stub is
// needed.
static int
stub_type_for_reloc(unsigned int r_type, AArch64_address address,
AArch64_address target);
Reloc_stub(int type)
: Stub_base<size, big_endian>(type)
{ }
~Reloc_stub()
{ }
// The key class used to index the stub instance in the stub table's stub map.
class Key
{
public:
Key(int type, const Symbol* symbol, const Relobj* relobj,
unsigned int r_sym, int32_t addend)
: type_(type), addend_(addend)
{
if (symbol != NULL)
{
this->r_sym_ = Reloc_stub::invalid_index;
this->u_.symbol = symbol;
}
else
{
gold_assert(relobj != NULL && r_sym != invalid_index);
this->r_sym_ = r_sym;
this->u_.relobj = relobj;
}
}
~Key()
{ }
// Return stub type.
int
type() const
{ return this->type_; }
// Return the local symbol index or invalid_index.
unsigned int
r_sym() const
{ return this->r_sym_; }
// Return the symbol if there is one.
const Symbol*
symbol() const
{ return this->r_sym_ == invalid_index ? this->u_.symbol : NULL; }
// Return the relobj if there is one.
const Relobj*
relobj() const
{ return this->r_sym_ != invalid_index ? this->u_.relobj : NULL; }
// Whether this equals to another key k.
bool
eq(const Key& k) const
{
return ((this->type_ == k.type_)
&& (this->r_sym_ == k.r_sym_)
&& ((this->r_sym_ != Reloc_stub::invalid_index)
? (this->u_.relobj == k.u_.relobj)
: (this->u_.symbol == k.u_.symbol))
&& (this->addend_ == k.addend_));
}
// Return a hash value.
size_t
hash_value() const
{
size_t name_hash_value = gold::string_hash<char>(
(this->r_sym_ != Reloc_stub::invalid_index)
? this->u_.relobj->name().c_str()
: this->u_.symbol->name());
// We only have 4 stub types.
size_t stub_type_hash_value = 0x03 & this->type_;
return (name_hash_value
^ stub_type_hash_value
^ ((this->r_sym_ & 0x3fff) << 2)
^ ((this->addend_ & 0xffff) << 16));
}
// Functors for STL associative containers.
struct hash
{
size_t
operator()(const Key& k) const
{ return k.hash_value(); }
};
struct equal_to
{
bool
operator()(const Key& k1, const Key& k2) const
{ return k1.eq(k2); }
};
private:
// Stub type.
const int type_;
// If this is a local symbol, this is the index in the defining object.
// Otherwise, it is invalid_index for a global symbol.
unsigned int r_sym_;
// If r_sym_ is an invalid index, this points to a global symbol.
// Otherwise, it points to a relobj. We used the unsized and target
// independent Symbol and Relobj classes instead of Sized_symbol<32> and
// Arm_relobj, in order to avoid making the stub class a template
// as most of the stub machinery is endianness-neutral. However, it
// may require a bit of casting done by users of this class.
union
{
const Symbol* symbol;
const Relobj* relobj;
} u_;
// Addend associated with a reloc.
int32_t addend_;
}; // End of inner class Reloc_stub::Key
protected:
// This may be overridden in the child class.
virtual void
do_write(unsigned char*, section_size_type);
private:
static const unsigned int invalid_index = static_cast<unsigned int>(-1);
}; // End of Reloc_stub
template<int size, bool big_endian>
const int Reloc_stub<size, big_endian>::STUB_ADDR_ALIGN = 4;
// Write data to output file.
template<int size, bool big_endian>
void
Reloc_stub<size, big_endian>::
do_write(unsigned char* view, section_size_type)
{
typedef typename elfcpp::Swap<32, big_endian>::Valtype Insntype;
const uint32_t* insns = this->insns();
uint32_t num_insns = this->insn_num();
Insntype* ip = reinterpret_cast<Insntype*>(view);
for (uint32_t i = 0; i < num_insns; ++i)
elfcpp::Swap<32, big_endian>::writeval(ip + i, insns[i]);
}
// Determine the stub type for a certain relocation or ST_NONE, if no stub is
// needed.
template<int size, bool big_endian>
inline int
Reloc_stub<size, big_endian>::stub_type_for_reloc(
unsigned int r_type, AArch64_address location, AArch64_address dest)
{
int64_t branch_offset = 0;
switch(r_type)
{
case elfcpp::R_AARCH64_CALL26:
case elfcpp::R_AARCH64_JUMP26:
branch_offset = dest - location;
break;
default:
gold_unreachable();
}
if (aarch64_valid_branch_offset_p(branch_offset))
return ST_NONE;
if (aarch64_valid_for_adrp_p(location, dest))
return ST_ADRP_BRANCH;
if (parameters->options().output_is_position_independent()
&& parameters->options().output_is_executable())
return ST_LONG_BRANCH_PCREL;
return ST_LONG_BRANCH_ABS;
}
// A class to hold stubs for the ARM target.
template<int size, bool big_endian>
class Stub_table : public Output_data
{
public:
typedef Target_aarch64<size, big_endian> The_target_aarch64;
typedef typename elfcpp::Elf_types<size>::Elf_Addr AArch64_address;
typedef AArch64_relobj<size, big_endian> The_aarch64_relobj;
typedef AArch64_input_section<size, big_endian> The_aarch64_input_section;
typedef Reloc_stub<size, big_endian> The_reloc_stub;
typedef typename The_reloc_stub::Key The_reloc_stub_key;
typedef Erratum_stub<size, big_endian> The_erratum_stub;
typedef Erratum_stub_less<size, big_endian> The_erratum_stub_less;
typedef typename The_reloc_stub_key::hash The_reloc_stub_key_hash;
typedef typename The_reloc_stub_key::equal_to The_reloc_stub_key_equal_to;
typedef Stub_table<size, big_endian> The_stub_table;
typedef Unordered_map<The_reloc_stub_key, The_reloc_stub*,
The_reloc_stub_key_hash, The_reloc_stub_key_equal_to>
Reloc_stub_map;
typedef typename Reloc_stub_map::const_iterator Reloc_stub_map_const_iter;
typedef Relocate_info<size, big_endian> The_relocate_info;
typedef std::set<The_erratum_stub*, The_erratum_stub_less> Erratum_stub_set;
typedef typename Erratum_stub_set::iterator Erratum_stub_set_iter;
Stub_table(The_aarch64_input_section* owner)
: Output_data(), owner_(owner), reloc_stubs_size_(0),
erratum_stubs_size_(0), prev_data_size_(0)
{ }
~Stub_table()
{ }
The_aarch64_input_section*
owner() const
{ return owner_; }
// Whether this stub table is empty.
bool
empty() const
{ return reloc_stubs_.empty() && erratum_stubs_.empty(); }
// Return the current data size.
off_t
current_data_size() const
{ return this->current_data_size_for_child(); }
// Add a STUB using KEY. The caller is responsible for avoiding addition
// if a STUB with the same key has already been added.
void
add_reloc_stub(The_reloc_stub* stub, const The_reloc_stub_key& key);
// Add an erratum stub into the erratum stub set. The set is ordered by
// (relobj, shndx, sh_offset).
void
add_erratum_stub(The_erratum_stub* stub);
// Find if such erratum exists for any given (obj, shndx, sh_offset).
The_erratum_stub*
find_erratum_stub(The_aarch64_relobj* a64relobj,
unsigned int shndx, unsigned int sh_offset);
// Find all the erratums for a given input section. The return value is a pair
// of iterators [begin, end).
std::pair<Erratum_stub_set_iter, Erratum_stub_set_iter>
find_erratum_stubs_for_input_section(The_aarch64_relobj* a64relobj,
unsigned int shndx);
// Compute the erratum stub address.
AArch64_address
erratum_stub_address(The_erratum_stub* stub) const
{
AArch64_address r = align_address(this->address() + this->reloc_stubs_size_,
The_erratum_stub::STUB_ADDR_ALIGN);
r += stub->offset();
return r;
}
// Finalize stubs. No-op here, just for completeness.
void
finalize_stubs()
{ }
// Look up a relocation stub using KEY. Return NULL if there is none.
The_reloc_stub*
find_reloc_stub(The_reloc_stub_key& key)
{
Reloc_stub_map_const_iter p = this->reloc_stubs_.find(key);
return (p != this->reloc_stubs_.end()) ? p->second : NULL;
}
// Relocate stubs in this stub table.
void
relocate_stubs(const The_relocate_info*,
The_target_aarch64*,
Output_section*,
unsigned char*,
AArch64_address,
section_size_type);
// Update data size at the end of a relaxation pass. Return true if data size
// is different from that of the previous relaxation pass.
bool
update_data_size_changed_p()
{
// No addralign changed here.
off_t s = align_address(this->reloc_stubs_size_,
The_erratum_stub::STUB_ADDR_ALIGN)
+ this->erratum_stubs_size_;
bool changed = (s != this->prev_data_size_);
this->prev_data_size_ = s;
return changed;
}
protected:
// Write out section contents.
void
do_write(Output_file*);
// Return the required alignment.
uint64_t
do_addralign() const
{
return std::max(The_reloc_stub::STUB_ADDR_ALIGN,
The_erratum_stub::STUB_ADDR_ALIGN);
}
// Reset address and file offset.
void
do_reset_address_and_file_offset()
{ this->set_current_data_size_for_child(this->prev_data_size_); }
// Set final data size.
void
set_final_data_size()
{ this->set_data_size(this->current_data_size()); }
private:
// Relocate one stub.
void
relocate_stub(The_reloc_stub*,
const The_relocate_info*,
The_target_aarch64*,
Output_section*,
unsigned char*,
AArch64_address,
section_size_type);
private:
// Owner of this stub table.
The_aarch64_input_section* owner_;
// The relocation stubs.
Reloc_stub_map reloc_stubs_;
// The erratum stubs.
Erratum_stub_set erratum_stubs_;
// Size of reloc stubs.
off_t reloc_stubs_size_;
// Size of erratum stubs.
off_t erratum_stubs_size_;
// data size of this in the previous pass.
off_t prev_data_size_;
}; // End of Stub_table
// Add an erratum stub into the erratum stub set. The set is ordered by
// (relobj, shndx, sh_offset).
template<int size, bool big_endian>
void
Stub_table<size, big_endian>::add_erratum_stub(The_erratum_stub* stub)
{
std::pair<Erratum_stub_set_iter, bool> ret =
this->erratum_stubs_.insert(stub);
gold_assert(ret.second);
this->erratum_stubs_size_ = align_address(
this->erratum_stubs_size_, The_erratum_stub::STUB_ADDR_ALIGN);
stub->set_offset(this->erratum_stubs_size_);
this->erratum_stubs_size_ += stub->stub_size();
}
// Find if such erratum exists for given (obj, shndx, sh_offset).
template<int size, bool big_endian>
Erratum_stub<size, big_endian>*
Stub_table<size, big_endian>::find_erratum_stub(
The_aarch64_relobj* a64relobj, unsigned int shndx, unsigned int sh_offset)
{
// A dummy object used as key to search in the set.
The_erratum_stub key(a64relobj, ST_NONE,
shndx, sh_offset);
Erratum_stub_set_iter i = this->erratum_stubs_.find(&key);
if (i != this->erratum_stubs_.end())
{
The_erratum_stub* stub(*i);
gold_assert(stub->erratum_insn() != 0);
return stub;
}
return NULL;
}
// Find all the errata for a given input section. The return value is a pair of
// iterators [begin, end).
template<int size, bool big_endian>
std::pair<typename Stub_table<size, big_endian>::Erratum_stub_set_iter,
typename Stub_table<size, big_endian>::Erratum_stub_set_iter>
Stub_table<size, big_endian>::find_erratum_stubs_for_input_section(
The_aarch64_relobj* a64relobj, unsigned int shndx)
{
typedef std::pair<Erratum_stub_set_iter, Erratum_stub_set_iter> Result_pair;
Erratum_stub_set_iter start, end;
The_erratum_stub low_key(a64relobj, ST_NONE, shndx, 0);
start = this->erratum_stubs_.lower_bound(&low_key);
if (start == this->erratum_stubs_.end())
return Result_pair(this->erratum_stubs_.end(),
this->erratum_stubs_.end());
end = start;
while (end != this->erratum_stubs_.end() &&
(*end)->relobj() == a64relobj && (*end)->shndx() == shndx)
++end;
return Result_pair(start, end);
}
// Add a STUB using KEY. The caller is responsible for avoiding addition
// if a STUB with the same key has already been added.
template<int size, bool big_endian>
void
Stub_table<size, big_endian>::add_reloc_stub(
The_reloc_stub* stub, const The_reloc_stub_key& key)
{
gold_assert(stub->type() == key.type());
this->reloc_stubs_[key] = stub;
// Assign stub offset early. We can do this because we never remove
// reloc stubs and they are in the beginning of the stub table.
this->reloc_stubs_size_ = align_address(this->reloc_stubs_size_,
The_reloc_stub::STUB_ADDR_ALIGN);
stub->set_offset(this->reloc_stubs_size_);
this->reloc_stubs_size_ += stub->stub_size();
}
// Relocate all stubs in this stub table.
template<int size, bool big_endian>
void
Stub_table<size, big_endian>::
relocate_stubs(const The_relocate_info* relinfo,
The_target_aarch64* target_aarch64,
Output_section* output_section,
unsigned char* view,
AArch64_address address,
section_size_type view_size)
{
// "view_size" is the total size of the stub_table.
gold_assert(address == this->address() &&
view_size == static_cast<section_size_type>(this->data_size()));
for(Reloc_stub_map_const_iter p = this->reloc_stubs_.begin();
p != this->reloc_stubs_.end(); ++p)
relocate_stub(p->second, relinfo, target_aarch64, output_section,
view, address, view_size);
// Just for convenience.
const int BPI = AArch64_insn_utilities<big_endian>::BYTES_PER_INSN;
// Now 'relocate' erratum stubs.
for(Erratum_stub_set_iter i = this->erratum_stubs_.begin();
i != this->erratum_stubs_.end(); ++i)
{
AArch64_address stub_address = this->erratum_stub_address(*i);
// The address of "b" in the stub that is to be "relocated".
AArch64_address stub_b_insn_address;
// Branch offset that is to be filled in "b" insn.
int b_offset = 0;
switch ((*i)->type())
{
case ST_E_843419:
case ST_E_835769:
// The 1st insn of the erratum could be a relocation spot,
// in this case we need to fix it with
// "(*i)->erratum_insn()".
elfcpp::Swap<32, big_endian>::writeval(
view + (stub_address - this->address()),
(*i)->erratum_insn());
// For the erratum, the 2nd insn is a b-insn to be patched
// (relocated).
stub_b_insn_address = stub_address + 1 * BPI;
b_offset = (*i)->destination_address() - stub_b_insn_address;
AArch64_relocate_functions<size, big_endian>::construct_b(
view + (stub_b_insn_address - this->address()),
((unsigned int)(b_offset)) & 0xfffffff);
break;
default:
gold_unreachable();
break;
}
}
}
// Relocate one stub. This is a helper for Stub_table::relocate_stubs().
template<int size, bool big_endian>
void
Stub_table<size, big_endian>::
relocate_stub(The_reloc_stub* stub,
const The_relocate_info* relinfo,
The_target_aarch64* target_aarch64,
Output_section* output_section,
unsigned char* view,
AArch64_address address,
section_size_type view_size)
{
// "offset" is the offset from the beginning of the stub_table.
section_size_type offset = stub->offset();
section_size_type stub_size = stub->stub_size();
// "view_size" is the total size of the stub_table.
gold_assert(offset + stub_size <= view_size);
target_aarch64->relocate_stub(stub, relinfo, output_section,
view + offset, address + offset, view_size);
}
// Write out the stubs to file.
template<int size, bool big_endian>
void
Stub_table<size, big_endian>::do_write(Output_file* of)
{
off_t offset = this->offset();
const section_size_type oview_size =
convert_to_section_size_type(this->data_size());
unsigned char* const oview = of->get_output_view(offset, oview_size);
// Write relocation stubs.
for (typename Reloc_stub_map::const_iterator p = this->reloc_stubs_.begin();
p != this->reloc_stubs_.end(); ++p)
{
The_reloc_stub* stub = p->second;
AArch64_address address = this->address() + stub->offset();
gold_assert(address ==
align_address(address, The_reloc_stub::STUB_ADDR_ALIGN));
stub->write(oview + stub->offset(), stub->stub_size());
}
// Write erratum stubs.
unsigned int erratum_stub_start_offset =
align_address(this->reloc_stubs_size_, The_erratum_stub::STUB_ADDR_ALIGN);
for (typename Erratum_stub_set::iterator p = this->erratum_stubs_.begin();
p != this->erratum_stubs_.end(); ++p)
{
The_erratum_stub* stub(*p);
stub->write(oview + erratum_stub_start_offset + stub->offset(),
stub->stub_size());
}
of->write_output_view(this->offset(), oview_size, oview);
}
// AArch64_relobj class.
template<int size, bool big_endian>
class AArch64_relobj : public Sized_relobj_file<size, big_endian>
{
public:
typedef AArch64_relobj<size, big_endian> This;
typedef Target_aarch64<size, big_endian> The_target_aarch64;
typedef AArch64_input_section<size, big_endian> The_aarch64_input_section;
typedef typename elfcpp::Elf_types<size>::Elf_Addr AArch64_address;
typedef Stub_table<size, big_endian> The_stub_table;
typedef Erratum_stub<size, big_endian> The_erratum_stub;
typedef typename The_stub_table::Erratum_stub_set_iter Erratum_stub_set_iter;
typedef std::vector<The_stub_table*> Stub_table_list;
static const AArch64_address invalid_address =
static_cast<AArch64_address>(-1);
AArch64_relobj(const std::string& name, Input_file* input_file, off_t offset,
const typename elfcpp::Ehdr<size, big_endian>& ehdr)
: Sized_relobj_file<size, big_endian>(name, input_file, offset, ehdr),
stub_tables_()
{ }
~AArch64_relobj()
{ }
// Return the stub table of the SHNDX-th section if there is one.
The_stub_table*
stub_table(unsigned int shndx) const
{
gold_assert(shndx < this->stub_tables_.size());
return this->stub_tables_[shndx];
}
// Set STUB_TABLE to be the stub_table of the SHNDX-th section.
void
set_stub_table(unsigned int shndx, The_stub_table* stub_table)
{
gold_assert(shndx < this->stub_tables_.size());
this->stub_tables_[shndx] = stub_table;
}
// Entrance to errata scanning.
void
scan_errata(unsigned int shndx,
const elfcpp::Shdr<size, big_endian>&,
Output_section*, const Symbol_table*,
The_target_aarch64*);
// Scan all relocation sections for stub generation.
void
scan_sections_for_stubs(The_target_aarch64*, const Symbol_table*,
const Layout*);
// Whether a section is a scannable text section.
bool
text_section_is_scannable(const elfcpp::Shdr<size, big_endian>&, unsigned int,
const Output_section*, const Symbol_table*);
// Convert regular input section with index SHNDX to a relaxed section.
void
convert_input_section_to_relaxed_section(unsigned /* shndx */)
{
// The stubs have relocations and we need to process them after writing
// out the stubs. So relocation now must follow section write.
this->set_relocs_must_follow_section_writes();
}
// Structure for mapping symbol position.
struct Mapping_symbol_position
{
Mapping_symbol_position(unsigned int shndx, AArch64_address offset):
shndx_(shndx), offset_(offset)
{}
// "<" comparator used in ordered_map container.
bool
operator<(const Mapping_symbol_position& p) const
{
return (this->shndx_ < p.shndx_
|| (this->shndx_ == p.shndx_ && this->offset_ < p.offset_));
}
// Section index.
unsigned int shndx_;
// Section offset.
AArch64_address offset_;
};
typedef std::map<Mapping_symbol_position, char> Mapping_symbol_info;
protected:
// Post constructor setup.
void
do_setup()
{
// Call parent's setup method.
Sized_relobj_file<size, big_endian>::do_setup();
// Initialize look-up tables.
this->stub_tables_.resize(this->shnum());
}
virtual void
do_relocate_sections(
const Symbol_table* symtab, const Layout* layout,
const unsigned char* pshdrs, Output_file* of,
typename Sized_relobj_file<size, big_endian>::Views* pviews);
// Count local symbols and (optionally) record mapping info.
virtual void
do_count_local_symbols(Stringpool_template<char>*,
Stringpool_template<char>*);
private:
// Fix all errata in the object.
void
fix_errata(typename Sized_relobj_file<size, big_endian>::Views* pviews);
// Try to fix erratum 843419 in an optimized way. Return true if patch is
// applied.
bool
try_fix_erratum_843419_optimized(
The_erratum_stub*,
typename Sized_relobj_file<size, big_endian>::View_size&);
// Whether a section needs to be scanned for relocation stubs.
bool
section_needs_reloc_stub_scanning(const elfcpp::Shdr<size, big_endian>&,
const Relobj::Output_sections&,
const Symbol_table*, const unsigned char*);
// List of stub tables.
Stub_table_list stub_tables_;
// Mapping symbol information sorted by (section index, section_offset).
Mapping_symbol_info mapping_symbol_info_;
}; // End of AArch64_relobj
// Override to record mapping symbol information.
template<int size, bool big_endian>
void
AArch64_relobj<size, big_endian>::do_count_local_symbols(
Stringpool_template<char>* pool, Stringpool_template<char>* dynpool)
{
Sized_relobj_file<size, big_endian>::do_count_local_symbols(pool, dynpool);
// Only erratum-fixing work needs mapping symbols, so skip this time consuming
// processing if not fixing erratum.
if (!parameters->options().fix_cortex_a53_843419()
&& !parameters->options().fix_cortex_a53_835769())
return;
const unsigned int loccount = this->local_symbol_count();
if (loccount == 0)
return;
// Read the symbol table section header.
const unsigned int symtab_shndx = this->symtab_shndx();
elfcpp::Shdr<size, big_endian>
symtabshdr(this, this->elf_file()->section_header(symtab_shndx));
gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
// Read the local symbols.
const int sym_size =elfcpp::Elf_sizes<size>::sym_size;
gold_assert(loccount == symtabshdr.get_sh_info());
off_t locsize = loccount * sym_size;
const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(),
locsize, true, true);
// For mapping symbol processing, we need to read the symbol names.
unsigned int strtab_shndx = this->adjust_shndx(symtabshdr.get_sh_link());
if (strtab_shndx >= this->shnum())
{
this->error(_("invalid symbol table name index: %u"), strtab_shndx);
return;
}
elfcpp::Shdr<size, big_endian>
strtabshdr(this, this->elf_file()->section_header(strtab_shndx));
if (strtabshdr.get_sh_type() != elfcpp::SHT_STRTAB)
{
this->error(_("symbol table name section has wrong type: %u"),
static_cast<unsigned int>(strtabshdr.get_sh_type()));
return;
}
const char* pnames =
reinterpret_cast<const char*>(this->get_view(strtabshdr.get_sh_offset(),
strtabshdr.get_sh_size(),
false, false));
// Skip the first dummy symbol.
psyms += sym_size;
typename Sized_relobj_file<size, big_endian>::Local_values*
plocal_values = this->local_values();
for (unsigned int i = 1; i < loccount; ++i, psyms += sym_size)
{
elfcpp::Sym<size, big_endian> sym(psyms);
Symbol_value<size>& lv((*plocal_values)[i]);
AArch64_address input_value = lv.input_value();
// Check to see if this is a mapping symbol. AArch64 mapping symbols are
// defined in "ELF for the ARM 64-bit Architecture", Table 4-4, Mapping
// symbols.
// Mapping symbols could be one of the following 4 forms -
// a) $x
// b) $x.<any...>
// c) $d
// d) $d.<any...>
const char* sym_name = pnames + sym.get_st_name();
if (sym_name[0] == '$' && (sym_name[1] == 'x' || sym_name[1] == 'd')
&& (sym_name[2] == '\0' || sym_name[2] == '.'))
{
bool is_ordinary;
unsigned int input_shndx =
this->adjust_sym_shndx(i, sym.get_st_shndx(), &is_ordinary);
gold_assert(is_ordinary);
Mapping_symbol_position msp(input_shndx, input_value);
// Insert mapping_symbol_info into map whose ordering is defined by
// (shndx, offset_within_section).
this->mapping_symbol_info_[msp] = sym_name[1];
}
}
}
// Fix all errata in the object.
template<int size, bool big_endian>
void
AArch64_relobj<size, big_endian>::fix_errata(
typename Sized_relobj_file<size, big_endian>::Views* pviews)
{
typedef typename elfcpp::Swap<32,big_endian>::Valtype Insntype;
unsigned int shnum = this->shnum();
for (unsigned int i = 1; i < shnum; ++i)
{
The_stub_table* stub_table = this->stub_table(i);
if (!stub_table)
continue;
std::pair<Erratum_stub_set_iter, Erratum_stub_set_iter>
ipair(stub_table->find_erratum_stubs_for_input_section(this, i));
Erratum_stub_set_iter p = ipair.first, end = ipair.second;
while (p != end)
{
The_erratum_stub* stub = *p;
typename Sized_relobj_file<size, big_endian>::View_size&
pview((*pviews)[i]);
// Double check data before fix.
gold_assert(pview.address + stub->sh_offset()
== stub->erratum_address());
// Update previously recorded erratum insn with relocated
// version.
Insntype* ip =
reinterpret_cast<Insntype*>(pview.view + stub->sh_offset());
Insntype insn_to_fix = ip[0];
stub->update_erratum_insn(insn_to_fix);
// First try to see if erratum is 843419 and if it can be fixed
// without using branch-to-stub.
if (!try_fix_erratum_843419_optimized(stub, pview))
{
// Replace the erratum insn with a branch-to-stub.
AArch64_address stub_address =
stub_table->erratum_stub_address(stub);
unsigned int b_offset = stub_address - stub->erratum_address();
AArch64_relocate_functions<size, big_endian>::construct_b(
pview.view + stub->sh_offset(), b_offset & 0xfffffff);
}
++p;
}
}
}
// This is an optimization for 843419. This erratum requires the sequence begin
// with 'adrp', when final value calculated by adrp fits in adr, we can just
// replace 'adrp' with 'adr', so we save 2 jumps per occurrence. (Note, however,
// in this case, we do not delete the erratum stub (too late to do so), it is
// merely generated without ever being called.)
template<int size, bool big_endian>
bool
AArch64_relobj<size, big_endian>::try_fix_erratum_843419_optimized(
The_erratum_stub* stub,
typename Sized_relobj_file<size, big_endian>::View_size& pview)
{
if (stub->type() != ST_E_843419)
return false;
typedef AArch64_insn_utilities<big_endian> Insn_utilities;
typedef typename elfcpp::Swap<32,big_endian>::Valtype Insntype;
E843419_stub<size, big_endian>* e843419_stub =
reinterpret_cast<E843419_stub<size, big_endian>*>(stub);
AArch64_address pc = pview.address + e843419_stub->adrp_sh_offset();
Insntype* adrp_view = reinterpret_cast<Insntype*>(
pview.view + e843419_stub->adrp_sh_offset());
Insntype adrp_insn = adrp_view[0];
gold_assert(Insn_utilities::is_adrp(adrp_insn));
// Get adrp 33-bit signed imm value.
int64_t adrp_imm = Insn_utilities::
aarch64_adrp_decode_imm(adrp_insn);
// adrp - final value transferred to target register is calculated as:
// PC[11:0] = Zeros(12)
// adrp_dest_value = PC + adrp_imm;
int64_t adrp_dest_value = (pc & ~((1 << 12) - 1)) + adrp_imm;
// adr -final value transferred to target register is calucalted as:
// PC + adr_imm
// So we have:
// PC + adr_imm = adrp_dest_value
// ==>
// adr_imm = adrp_dest_value - PC
int64_t adr_imm = adrp_dest_value - pc;
// Check if imm fits in adr (21-bit signed).
if (-(1 << 20) <= adr_imm && adr_imm < (1 << 20))
{
// Convert 'adrp' into 'adr'.
Insntype adr_insn = adrp_insn & ((1u << 31) - 1);
adr_insn = Insn_utilities::
aarch64_adr_encode_imm(adr_insn, adr_imm);
elfcpp::Swap<32, big_endian>::writeval(adrp_view, adr_insn);
return true;
}
return false;
}
// Relocate sections.
template<int size, bool big_endian>
void
AArch64_relobj<size, big_endian>::do_relocate_sections(
const Symbol_table* symtab, const Layout* layout,
const unsigned char* pshdrs, Output_file* of,
typename Sized_relobj_file<size, big_endian>::Views* pviews)
{
// Call parent to relocate sections.
Sized_relobj_file<size, big_endian>::do_relocate_sections(symtab, layout,
pshdrs, of, pviews);
// We do not generate stubs if doing a relocatable link.
if (parameters->options().relocatable())
return;
if (parameters->options().fix_cortex_a53_843419()
|| parameters->options().fix_cortex_a53_835769())
this->fix_errata(pviews);
Relocate_info<size, big_endian> relinfo;
relinfo.symtab = symtab;
relinfo.layout = layout;
relinfo.object = this;
// Relocate stub tables.
unsigned int shnum = this->shnum();
The_target_aarch64* target = The_target_aarch64::current_target();
for (unsigned int i = 1; i < shnum; ++i)
{
The_aarch64_input_section* aarch64_input_section =
target->find_aarch64_input_section(this, i);
if (aarch64_input_section != NULL
&& aarch64_input_section->is_stub_table_owner()
&& !aarch64_input_section->stub_table()->empty())
{
Output_section* os = this->output_section(i);
gold_assert(os != NULL);
relinfo.reloc_shndx = elfcpp::SHN_UNDEF;
relinfo.reloc_shdr = NULL;
relinfo.data_shndx = i;
relinfo.data_shdr = pshdrs + i * elfcpp::Elf_sizes<size>::shdr_size;
typename Sized_relobj_file<size, big_endian>::View_size&
view_struct = (*pviews)[i];
gold_assert(view_struct.view != NULL);
The_stub_table* stub_table = aarch64_input_section->stub_table();
off_t offset = stub_table->address() - view_struct.address;
unsigned char* view = view_struct.view + offset;
AArch64_address address = stub_table->address();
section_size_type view_size = stub_table->data_size();
stub_table->relocate_stubs(&relinfo, target, os, view, address,
view_size);
}
}
}
// Determine if an input section is scannable for stub processing. SHDR is
// the header of the section and SHNDX is the section index. OS is the output
// section for the input section and SYMTAB is the global symbol table used to
// look up ICF information.
template<int size, bool big_endian>
bool
AArch64_relobj<size, big_endian>::text_section_is_scannable(
const elfcpp::Shdr<size, big_endian>& text_shdr,
unsigned int text_shndx,
const Output_section* os,
const Symbol_table* symtab)
{
// Skip any empty sections, unallocated sections or sections whose
// type are not SHT_PROGBITS.
if (text_shdr.get_sh_size() == 0
|| (text_shdr.get_sh_flags() & elfcpp::SHF_ALLOC) == 0
|| text_shdr.get_sh_type() != elfcpp::SHT_PROGBITS)
return false;
// Skip any discarded or ICF'ed sections.
if (os == NULL || symtab->is_section_folded(this, text_shndx))
return false;
// Skip exception frame.
if (strcmp(os->name(), ".eh_frame") == 0)
return false ;
gold_assert(!this->is_output_section_offset_invalid(text_shndx) ||
os->find_relaxed_input_section(this, text_shndx) != NULL);
return true;
}
// Determine if we want to scan the SHNDX-th section for relocation stubs.
// This is a helper for AArch64_relobj::scan_sections_for_stubs().
template<int size, bool big_endian>
bool
AArch64_relobj<size, big_endian>::section_needs_reloc_stub_scanning(
const elfcpp::Shdr<size, big_endian>& shdr,
const Relobj::Output_sections& out_sections,
const Symbol_table* symtab,
const unsigned char* pshdrs)
{
unsigned int sh_type = shdr.get_sh_type();
if (sh_type != elfcpp::SHT_RELA)
return false;
// Ignore empty section.
off_t sh_size = shdr.get_sh_size();
if (sh_size == 0)
return false;
// Ignore reloc section with unexpected symbol table. The
// error will be reported in the final link.
if (this->adjust_shndx(shdr.get_sh_link()) != this->symtab_shndx())
return false;
gold_assert(sh_type == elfcpp::SHT_RELA);
unsigned int reloc_size = elfcpp::Elf_sizes<size>::rela_size;
// Ignore reloc section with unexpected entsize or uneven size.
// The error will be reported in the final link.
if (reloc_size != shdr.get_sh_entsize() || sh_size % reloc_size != 0)
return false;
// Ignore reloc section with bad info. This error will be
// reported in the final link.
unsigned int text_shndx = this->adjust_shndx(shdr.get_sh_info());
if (text_shndx >= this->shnum())
return false;
const unsigned int shdr_size = elfcpp::Elf_sizes<size>::shdr_size;
const elfcpp::Shdr<size, big_endian> text_shdr(pshdrs +
text_shndx * shdr_size);
return this->text_section_is_scannable(text_shdr, text_shndx,
out_sections[text_shndx], symtab);
}
// Scan section SHNDX for erratum 843419 and 835769.
template<int size, bool big_endian>
void
AArch64_relobj<size, big_endian>::scan_errata(
unsigned int shndx, const elfcpp::Shdr<size, big_endian>& shdr,
Output_section* os, const Symbol_table* symtab,
The_target_aarch64* target)
{
if (shdr.get_sh_size() == 0
|| (shdr.get_sh_flags() &
(elfcpp::SHF_ALLOC | elfcpp::SHF_EXECINSTR)) == 0
|| shdr.get_sh_type() != elfcpp::SHT_PROGBITS)
return;
if (!os || symtab->is_section_folded(this, shndx)) return;
AArch64_address output_offset = this->get_output_section_offset(shndx);
AArch64_address output_address;
if (output_offset != invalid_address)
output_address = os->address() + output_offset;
else
{
const Output_relaxed_input_section* poris =
os->find_relaxed_input_section(this, shndx);
if (!poris) return;
output_address = poris->address();
}
section_size_type input_view_size = 0;
const unsigned char* input_view =
this->section_contents(shndx, &input_view_size, false);
Mapping_symbol_position section_start(shndx, 0);
// Find the first mapping symbol record within section shndx.
typename Mapping_symbol_info::const_iterator p =
this->mapping_symbol_info_.lower_bound(section_start);
while (p != this->mapping_symbol_info_.end() &&
p->first.shndx_ == shndx)
{
typename Mapping_symbol_info::const_iterator prev = p;
++p;
if (prev->second == 'x')
{
section_size_type span_start =
convert_to_section_size_type(prev->first.offset_);
section_size_type span_end;
if (p != this->mapping_symbol_info_.end()
&& p->first.shndx_ == shndx)
span_end = convert_to_section_size_type(p->first.offset_);
else
span_end = convert_to_section_size_type(shdr.get_sh_size());
// Here we do not share the scanning code of both errata. For 843419,
// only the last few insns of each page are examined, which is fast,
// whereas, for 835769, every insn pair needs to be checked.
if (parameters->options().fix_cortex_a53_843419())
target->scan_erratum_843419_span(
this, shndx, span_start, span_end,
const_cast<unsigned char*>(input_view), output_address);
if (parameters->options().fix_cortex_a53_835769())
target->scan_erratum_835769_span(
this, shndx, span_start, span_end,
const_cast<unsigned char*>(input_view), output_address);
}
}
}
// Scan relocations for stub generation.
template<int size, bool big_endian>
void
AArch64_relobj<size, big_endian>::scan_sections_for_stubs(
The_target_aarch64* target,
const Symbol_table* symtab,
const Layout* layout)
{
unsigned int shnum = this->shnum();
const unsigned int shdr_size = elfcpp::Elf_sizes<size>::shdr_size;
// Read the section headers.
const unsigned char* pshdrs = this->get_view(this->elf_file()->shoff(),
shnum * shdr_size,
true, true);
// To speed up processing, we set up hash tables for fast lookup of
// input offsets to output addresses.
this->initialize_input_to_output_maps();
const Relobj::Output_sections& out_sections(this->output_sections());
Relocate_info<size, big_endian> relinfo;
relinfo.symtab = symtab;
relinfo.layout = layout;
relinfo.object = this;
// Do relocation stubs scanning.
const unsigned char* p = pshdrs + shdr_size;
for (unsigned int i = 1; i < shnum; ++i, p += shdr_size)
{
const elfcpp::Shdr<size, big_endian> shdr(p);
if (parameters->options().fix_cortex_a53_843419()
|| parameters->options().fix_cortex_a53_835769())
scan_errata(i, shdr, out_sections[i], symtab, target);
if (this->section_needs_reloc_stub_scanning(shdr, out_sections, symtab,
pshdrs))
{
unsigned int index = this->adjust_shndx(shdr.get_sh_info());
AArch64_address output_offset =
this->get_output_section_offset(index);
AArch64_address output_address;
if (output_offset != invalid_address)
{
output_address = out_sections[index]->address() + output_offset;
}
else
{
// Currently this only happens for a relaxed section.
const Output_relaxed_input_section* poris =
out_sections[index]->find_relaxed_input_section(this, index);
gold_assert(poris != NULL);
output_address = poris->address();
}
// Get the relocations.
const unsigned char* prelocs = this->get_view(shdr.get_sh_offset(),
shdr.get_sh_size(),
true, false);
// Get the section contents.
section_size_type input_view_size = 0;
const unsigned char* input_view =
this->section_contents(index, &input_view_size, false);
relinfo.reloc_shndx = i;
relinfo.data_shndx = index;
unsigned int sh_type = shdr.get_sh_type();
unsigned int reloc_size;
gold_assert (sh_type == elfcpp::SHT_RELA);
reloc_size = elfcpp::Elf_sizes<size>::rela_size;
Output_section* os = out_sections[index];
target->scan_section_for_stubs(&relinfo, sh_type, prelocs,
shdr.get_sh_size() / reloc_size,
os,
output_offset == invalid_address,
input_view, output_address,
input_view_size);
}
}
}
// A class to wrap an ordinary input section containing executable code.
template<int size, bool big_endian>
class AArch64_input_section : public Output_relaxed_input_section
{
public:
typedef Stub_table<size, big_endian> The_stub_table;
AArch64_input_section(Relobj* relobj, unsigned int shndx)
: Output_relaxed_input_section(relobj, shndx, 1),
stub_table_(NULL),
original_contents_(NULL), original_size_(0),
original_addralign_(1)
{ }
~AArch64_input_section()
{ delete[] this->original_contents_; }
// Initialize.
void
init();
// Set the stub_table.
void
set_stub_table(The_stub_table* st)
{ this->stub_table_ = st; }
// Whether this is a stub table owner.
bool
is_stub_table_owner() const
{ return this->stub_table_ != NULL && this->stub_table_->owner() == this; }
// Return the original size of the section.
uint32_t
original_size() const
{ return this->original_size_; }
// Return the stub table.
The_stub_table*
stub_table()
{ return stub_table_; }
protected:
// Write out this input section.
void
do_write(Output_file*);
// Return required alignment of this.
uint64_t
do_addralign() const
{
if (this->is_stub_table_owner())
return std::max(this->stub_table_->addralign(),
static_cast<uint64_t>(this->original_addralign_));
else
return this->original_addralign_;
}
// Finalize data size.
void
set_final_data_size();
// Reset address and file offset.
void
do_reset_address_and_file_offset();
// Output offset.
bool
do_output_offset(const Relobj* object, unsigned int shndx,
section_offset_type offset,
section_offset_type* poutput) const
{
if ((object == this->relobj())
&& (shndx == this->shndx())
&& (offset >= 0)
&& (offset <=
convert_types<section_offset_type, uint32_t>(this->original_size_)))
{
*poutput = offset;
return true;
}
else
return false;
}
private:
// Copying is not allowed.
AArch64_input_section(const AArch64_input_section&);
AArch64_input_section& operator=(const AArch64_input_section&);
// The relocation stubs.
The_stub_table* stub_table_;
// Original section contents. We have to make a copy here since the file
// containing the original section may not be locked when we need to access
// the contents.
unsigned char* original_contents_;
// Section size of the original input section.
uint32_t original_size_;
// Address alignment of the original input section.
uint32_t original_addralign_;
}; // End of AArch64_input_section
// Finalize data size.
template<int size, bool big_endian>
void
AArch64_input_section<size, big_endian>::set_final_data_size()
{
off_t off = convert_types<off_t, uint64_t>(this->original_size_);
if (this->is_stub_table_owner())
{
this->stub_table_->finalize_data_size();
off = align_address(off, this->stub_table_->addralign());
off += this->stub_table_->data_size();
}
this->set_data_size(off);
}
// Reset address and file offset.
template<int size, bool big_endian>
void
AArch64_input_section<size, big_endian>::do_reset_address_and_file_offset()
{
// Size of the original input section contents.
off_t off = convert_types<off_t, uint64_t>(this->original_size_);
// If this is a stub table owner, account for the stub table size.
if (this->is_stub_table_owner())
{
The_stub_table* stub_table = this->stub_table_;
// Reset the stub table's address and file offset. The
// current data size for child will be updated after that.
stub_table_->reset_address_and_file_offset();
off = align_address(off, stub_table_->addralign());
off += stub_table->current_data_size();
}
this->set_current_data_size(off);
}
// Initialize an Arm_input_section.
template<int size, bool big_endian>
void
AArch64_input_section<size, big_endian>::init()
{
Relobj* relobj = this->relobj();
unsigned int shndx = this->shndx();
// We have to cache original size, alignment and contents to avoid locking
// the original file.
this->original_addralign_ =
convert_types<uint32_t, uint64_t>(relobj->section_addralign(shndx));
// This is not efficient but we expect only a small number of relaxed
// input sections for stubs.
section_size_type section_size;
const unsigned char* section_contents =
relobj->section_contents(shndx, &section_size, false);
this->original_size_ =
convert_types<uint32_t, uint64_t>(relobj->section_size(shndx));
gold_assert(this->original_contents_ == NULL);
this->original_contents_ = new unsigned char[section_size];
memcpy(this->original_contents_, section_contents, section_size);
// We want to make this look like the original input section after
// output sections are finalized.
Output_section* os = relobj->output_section(shndx);
off_t offset = relobj->output_section_offset(shndx);
gold_assert(os != NULL && !relobj->is_output_section_offset_invalid(shndx));
this->set_address(os->address() + offset);
this->set_file_offset(os->offset() + offset);
this->set_current_data_size(this->original_size_);
this->finalize_data_size();
}
// Write data to output file.
template<int size, bool big_endian>
void
AArch64_input_section<size, big_endian>::do_write(Output_file* of)
{
// We have to write out the original section content.
gold_assert(this->original_contents_ != NULL);
of->write(this->offset(), this->original_contents_,
this->original_size_);
// If this owns a stub table and it is not empty, write it.
if (this->is_stub_table_owner() && !this->stub_table_->empty())
this->stub_table_->write(of);
}
// Arm output section class. This is defined mainly to add a number of stub
// generation methods.
template<int size, bool big_endian>
class AArch64_output_section : public Output_section
{
public:
typedef Target_aarch64<size, big_endian> The_target_aarch64;
typedef AArch64_relobj<size, big_endian> The_aarch64_relobj;
typedef Stub_table<size, big_endian> The_stub_table;
typedef AArch64_input_section<size, big_endian> The_aarch64_input_section;
public:
AArch64_output_section(const char* name, elfcpp::Elf_Word type,
elfcpp::Elf_Xword flags)
: Output_section(name, type, flags)
{ }
~AArch64_output_section() {}
// Group input sections for stub generation.
void
group_sections(section_size_type, bool, Target_aarch64<size, big_endian>*,
const Task*);
private:
typedef Output_section::Input_section Input_section;
typedef Output_section::Input_section_list Input_section_list;
// Create a stub group.
void
create_stub_group(Input_section_list::const_iterator,
Input_section_list::const_iterator,
Input_section_list::const_iterator,
The_target_aarch64*,
std::vector<Output_relaxed_input_section*>&,
const Task*);
}; // End of AArch64_output_section
// Create a stub group for input sections from FIRST to LAST. OWNER points to
// the input section that will be the owner of the stub table.
template<int size, bool big_endian> void
AArch64_output_section<size, big_endian>::create_stub_group(
Input_section_list::const_iterator first,
Input_section_list::const_iterator last,
Input_section_list::const_iterator owner,
The_target_aarch64* target,
std::vector<Output_relaxed_input_section*>& new_relaxed_sections,
const Task* task)
{
// Currently we convert ordinary input sections into relaxed sections only
// at this point.
The_aarch64_input_section* input_section;
if (owner->is_relaxed_input_section())
gold_unreachable();
else
{
gold_assert(owner->is_input_section());
// Create a new relaxed input section. We need to lock the original
// file.
Task_lock_obj<Object> tl(task, owner->relobj());
input_section =
target->new_aarch64_input_section(owner->relobj(), owner->shndx());
new_relaxed_sections.push_back(input_section);
}
// Create a stub table.
The_stub_table* stub_table =
target->new_stub_table(input_section);
input_section->set_stub_table(stub_table);
Input_section_list::const_iterator p = first;
// Look for input sections or relaxed input sections in [first ... last].
do
{
if (p->is_input_section() || p->is_relaxed_input_section())
{
// The stub table information for input sections live
// in their objects.
The_aarch64_relobj* aarch64_relobj =
static_cast<The_aarch64_relobj*>(p->relobj());
aarch64_relobj->set_stub_table(p->shndx(), stub_table);
}
}
while (p++ != last);
}
// Group input sections for stub generation. GROUP_SIZE is roughly the limit of
// stub groups. We grow a stub group by adding input section until the size is
// just below GROUP_SIZE. The last input section will be converted into a stub
// table owner. If STUB_ALWAYS_AFTER_BRANCH is false, we also add input sectiond
// after the stub table, effectively doubling the group size.
//
// This is similar to the group_sections() function in elf32-arm.c but is
// implemented differently.
template<int size, bool big_endian>
void AArch64_output_section<size, big_endian>::group_sections(
section_size_type group_size,
bool stubs_always_after_branch,
Target_aarch64<size, big_endian>* target,
const Task* task)
{
typedef enum
{
NO_GROUP,
FINDING_STUB_SECTION,
HAS_STUB_SECTION
} State;
std::vector<Output_relaxed_input_section*> new_relaxed_sections;
State state = NO_GROUP;
section_size_type off = 0;
section_size_type group_begin_offset = 0;
section_size_type group_end_offset = 0;
section_size_type stub_table_end_offset = 0;
Input_section_list::const_iterator group_begin =
this->input_sections().end();
Input_section_list::const_iterator stub_table =
this->input_sections().end();
Input_section_list::const_iterator group_end = this->input_sections().end();
for (Input_section_list::const_iterator p = this->input_sections().begin();
p != this->input_sections().end();
++p)
{
section_size_type section_begin_offset =
align_address(off, p->addralign());
section_size_type section_end_offset =
section_begin_offset + p->data_size();
// Check to see if we should group the previously seen sections.
switch (state)
{
case NO_GROUP:
break;
case FINDING_STUB_SECTION:
// Adding this section makes the group larger than GROUP_SIZE.
if (section_end_offset - group_begin_offset >= group_size)
{
if (stubs_always_after_branch)
{
gold_assert(group_end != this->input_sections().end());
this->create_stub_group(group_begin, group_end, group_end,
target, new_relaxed_sections,
task);
state = NO_GROUP;
}
else
{
// Input sections up to stub_group_size bytes after the stub
// table can be handled by it too.
state = HAS_STUB_SECTION;
stub_table = group_end;
stub_table_end_offset = group_end_offset;
}
}
break;
case HAS_STUB_SECTION:
// Adding this section makes the post stub-section group larger
// than GROUP_SIZE.
gold_unreachable();
// NOT SUPPORTED YET. For completeness only.
if (section_end_offset - stub_table_end_offset >= group_size)
{
gold_assert(group_end != this->input_sections().end());
this->create_stub_group(group_begin, group_end, stub_table,
target, new_relaxed_sections, task);
state = NO_GROUP;
}
break;
default:
gold_unreachable();
}
// If we see an input section and currently there is no group, start
// a new one. Skip any empty sections. We look at the data size
// instead of calling p->relobj()->section_size() to avoid locking.
if ((p->is_input_section() || p->is_relaxed_input_section())
&& (p->data_size() != 0))
{
if (state == NO_GROUP)
{
state = FINDING_STUB_SECTION;
group_begin = p;
group_begin_offset = section_begin_offset;
}
// Keep track of the last input section seen.
group_end = p;
group_end_offset = section_end_offset;
}
off = section_end_offset;
}
// Create a stub group for any ungrouped sections.
if (state == FINDING_STUB_SECTION || state == HAS_STUB_SECTION)
{
gold_assert(group_end != this->input_sections().end());
this->create_stub_group(group_begin, group_end,
(state == FINDING_STUB_SECTION
? group_end
: stub_table),
target, new_relaxed_sections, task);
}
if (!new_relaxed_sections.empty())
this->convert_input_sections_to_relaxed_sections(new_relaxed_sections);
// Update the section offsets
for (size_t i = 0; i < new_relaxed_sections.size(); ++i)
{
The_aarch64_relobj* relobj = static_cast<The_aarch64_relobj*>(
new_relaxed_sections[i]->relobj());
unsigned int shndx = new_relaxed_sections[i]->shndx();
// Tell AArch64_relobj that this input section is converted.
relobj->convert_input_section_to_relaxed_section(shndx);
}
} // End of AArch64_output_section::group_sections
AArch64_reloc_property_table* aarch64_reloc_property_table = NULL;
// The aarch64 target class.
// See the ABI at
// http://infocenter.arm.com/help/topic/com.arm.doc.ihi0056b/IHI0056B_aaelf64.pdf
template<int size, bool big_endian>
class Target_aarch64 : public Sized_target<size, big_endian>
{
public:
typedef Target_aarch64<size, big_endian> This;
typedef Output_data_reloc<elfcpp::SHT_RELA, true, size, big_endian>
Reloc_section;
typedef Relocate_info<size, big_endian> The_relocate_info;
typedef typename elfcpp::Elf_types<size>::Elf_Addr Address;
typedef AArch64_relobj<size, big_endian> The_aarch64_relobj;
typedef Reloc_stub<size, big_endian> The_reloc_stub;
typedef Erratum_stub<size, big_endian> The_erratum_stub;
typedef typename Reloc_stub<size, big_endian>::Key The_reloc_stub_key;
typedef Stub_table<size, big_endian> The_stub_table;
typedef std::vector<The_stub_table*> Stub_table_list;
typedef typename Stub_table_list::iterator Stub_table_iterator;
typedef AArch64_input_section<size, big_endian> The_aarch64_input_section;
typedef AArch64_output_section<size, big_endian> The_aarch64_output_section;
typedef Unordered_map<Section_id,
AArch64_input_section<size, big_endian>*,
Section_id_hash> AArch64_input_section_map;
typedef AArch64_insn_utilities<big_endian> Insn_utilities;
const static int TCB_SIZE = size / 8 * 2;
Target_aarch64(const Target::Target_info* info = &aarch64_info)
: Sized_target<size, big_endian>(info),
got_(NULL), plt_(NULL), got_plt_(NULL), got_irelative_(NULL),
got_tlsdesc_(NULL), global_offset_table_(NULL), rela_dyn_(NULL),
rela_irelative_(NULL), copy_relocs_(elfcpp::R_AARCH64_COPY),
got_mod_index_offset_(-1U),
tlsdesc_reloc_info_(), tls_base_symbol_defined_(false),
stub_tables_(), stub_group_size_(0), aarch64_input_section_map_()
{ }
// Scan the relocations to determine unreferenced sections for
// garbage collection.
void
gc_process_relocs(Symbol_table* symtab,
Layout* layout,
Sized_relobj_file<size, big_endian>* object,
unsigned int data_shndx,
unsigned int sh_type,
const unsigned char* prelocs,
size_t reloc_count,
Output_section* output_section,
bool needs_special_offset_handling,
size_t local_symbol_count,
const unsigned char* plocal_symbols);
// Scan the relocations to look for symbol adjustments.
void
scan_relocs(Symbol_table* symtab,
Layout* layout,
Sized_relobj_file<size, big_endian>* object,
unsigned int data_shndx,
unsigned int sh_type,
const unsigned char* prelocs,
size_t reloc_count,
Output_section* output_section,
bool needs_special_offset_handling,
size_t local_symbol_count,
const unsigned char* plocal_symbols);
// Finalize the sections.
void
do_finalize_sections(Layout*, const Input_objects*, Symbol_table*);
// Return the value to use for a dynamic which requires special
// treatment.
uint64_t
do_dynsym_value(const Symbol*) const;
// Relocate a section.
void
relocate_section(const Relocate_info<size, big_endian>*,
unsigned int sh_type,
const unsigned char* prelocs,
size_t reloc_count,
Output_section* output_section,
bool needs_special_offset_handling,
unsigned char* view,
typename elfcpp::Elf_types<size>::Elf_Addr view_address,
section_size_type view_size,
const Reloc_symbol_changes*);
// Scan the relocs during a relocatable link.
void
scan_relocatable_relocs(Symbol_table* symtab,
Layout* layout,
Sized_relobj_file<size, big_endian>* object,
unsigned int data_shndx,
unsigned int sh_type,
const unsigned char* prelocs,
size_t reloc_count,
Output_section* output_section,
bool needs_special_offset_handling,
size_t local_symbol_count,
const unsigned char* plocal_symbols,
Relocatable_relocs*);
// Relocate a section during a relocatable link.
void
relocate_relocs(
const Relocate_info<size, big_endian>*,
unsigned int sh_type,
const unsigned char* prelocs,
size_t reloc_count,
Output_section* output_section,
typename elfcpp::Elf_types<size>::Elf_Off offset_in_output_section,
unsigned char* view,
typename elfcpp::Elf_types<size>::Elf_Addr view_address,
section_size_type view_size,
unsigned char* reloc_view,
section_size_type reloc_view_size);
// Return the symbol index to use for a target specific relocation.
// The only target specific relocation is R_AARCH64_TLSDESC for a
// local symbol, which is an absolute reloc.
unsigned int
do_reloc_symbol_index(void*, unsigned int r_type) const
{
gold_assert(r_type == elfcpp::R_AARCH64_TLSDESC);
return 0;
}
// Return the addend to use for a target specific relocation.
uint64_t
do_reloc_addend(void* arg, unsigned int r_type, uint64_t addend) const;
// Return the PLT section.
uint64_t
do_plt_address_for_global(const Symbol* gsym) const
{ return this->plt_section()->address_for_global(gsym); }
uint64_t
do_plt_address_for_local(const Relobj* relobj, unsigned int symndx) const
{ return this->plt_section()->address_for_local(relobj, symndx); }
// This function should be defined in targets that can use relocation
// types to determine (implemented in local_reloc_may_be_function_pointer
// and global_reloc_may_be_function_pointer)
// if a function's pointer is taken. ICF uses this in safe mode to only
// fold those functions whose pointer is defintely not taken.
bool
do_can_check_for_function_pointers() const
{ return true; }
// Return the number of entries in the PLT.
unsigned int
plt_entry_count() const;
//Return the offset of the first non-reserved PLT entry.
unsigned int
first_plt_entry_offset() const;
// Return the size of each PLT entry.
unsigned int
plt_entry_size() const;
// Create a stub table.
The_stub_table*
new_stub_table(The_aarch64_input_section*);
// Create an aarch64 input section.
The_aarch64_input_section*
new_aarch64_input_section(Relobj*, unsigned int);
// Find an aarch64 input section instance for a given OBJ and SHNDX.
The_aarch64_input_section*
find_aarch64_input_section(Relobj*, unsigned int) const;
// Return the thread control block size.
unsigned int
tcb_size() const { return This::TCB_SIZE; }
// Scan a section for stub generation.
void
scan_section_for_stubs(const Relocate_info<size, big_endian>*, unsigned int,
const unsigned char*, size_t, Output_section*,
bool, const unsigned char*,
Address,
section_size_type);
// Scan a relocation section for stub.
template<int sh_type>
void
scan_reloc_section_for_stubs(
const The_relocate_info* relinfo,
const unsigned char* prelocs,
size_t reloc_count,
Output_section* output_section,
bool needs_special_offset_handling,
const unsigned char* view,
Address view_address,
section_size_type);
// Relocate a single stub.
void
relocate_stub(The_reloc_stub*, const Relocate_info<size, big_endian>*,
Output_section*, unsigned char*, Address,
section_size_type);
// Get the default AArch64 target.
static This*
current_target()
{
gold_assert(parameters->target().machine_code() == elfcpp::EM_AARCH64
&& parameters->target().get_size() == size
&& parameters->target().is_big_endian() == big_endian);
return static_cast<This*>(parameters->sized_target<size, big_endian>());
}
// Scan erratum 843419 for a part of a section.
void
scan_erratum_843419_span(
AArch64_relobj<size, big_endian>*,
unsigned int,
const section_size_type,
const section_size_type,
unsigned char*,
Address);
// Scan erratum 835769 for a part of a section.
void
scan_erratum_835769_span(
AArch64_relobj<size, big_endian>*,
unsigned int,
const section_size_type,
const section_size_type,
unsigned char*,
Address);
protected:
void
do_select_as_default_target()
{
gold_assert(aarch64_reloc_property_table == NULL);
aarch64_reloc_property_table = new AArch64_reloc_property_table();
}
// Add a new reloc argument, returning the index in the vector.
size_t
add_tlsdesc_info(Sized_relobj_file<size, big_endian>* object,
unsigned int r_sym)
{
this->tlsdesc_reloc_info_.push_back(Tlsdesc_info(object, r_sym));
return this->tlsdesc_reloc_info_.size() - 1;
}
virtual Output_data_plt_aarch64<size, big_endian>*
do_make_data_plt(Layout* layout,
Output_data_got_aarch64<size, big_endian>* got,
Output_data_space* got_plt,
Output_data_space* got_irelative)
{
return new Output_data_plt_aarch64_standard<size, big_endian>(
layout, got, got_plt, got_irelative);
}
// do_make_elf_object to override the same function in the base class.
Object*
do_make_elf_object(const std::string&, Input_file*, off_t,
const elfcpp::Ehdr<size, big_endian>&);
Output_data_plt_aarch64<size, big_endian>*
make_data_plt(Layout* layout,
Output_data_got_aarch64<size, big_endian>* got,
Output_data_space* got_plt,
Output_data_space* got_irelative)
{
return this->do_make_data_plt(layout, got, got_plt, got_irelative);
}
// We only need to generate stubs, and hence perform relaxation if we are
// not doing relocatable linking.
virtual bool
do_may_relax() const
{ return !parameters->options().relocatable(); }
// Relaxation hook. This is where we do stub generation.
virtual bool
do_relax(int, const Input_objects*, Symbol_table*, Layout*, const Task*);
void
group_sections(Layout* layout,
section_size_type group_size,
bool stubs_always_after_branch,
const Task* task);
void
scan_reloc_for_stub(const The_relocate_info*, unsigned int,
const Sized_symbol<size>*, unsigned int,
const Symbol_value<size>*,
typename elfcpp::Elf_types<size>::Elf_Swxword,
Address Elf_Addr);
// Make an output section.
Output_section*
do_make_output_section(const char* name, elfcpp::Elf_Word type,
elfcpp::Elf_Xword flags)
{ return new The_aarch64_output_section(name, type, flags); }
private:
// The class which scans relocations.
class Scan
{
public:
Scan()
: issued_non_pic_error_(false)
{ }
inline void
local(Symbol_table* symtab, Layout* layout, Target_aarch64* target,
Sized_relobj_file<size, big_endian>* object,
unsigned int data_shndx,
Output_section* output_section,
const elfcpp::Rela<size, big_endian>& reloc, unsigned int r_type,
const elfcpp::Sym<size, big_endian>& lsym,
bool is_discarded);
inline void
global(Symbol_table* symtab, Layout* layout, Target_aarch64* target,
Sized_relobj_file<size, big_endian>* object,
unsigned int data_shndx,
Output_section* output_section,
const elfcpp::Rela<size, big_endian>& reloc, unsigned int r_type,
Symbol* gsym);
inline bool
local_reloc_may_be_function_pointer(Symbol_table* , Layout* ,
Target_aarch64<size, big_endian>* ,
Sized_relobj_file<size, big_endian>* ,
unsigned int ,
Output_section* ,
const elfcpp::Rela<size, big_endian>& ,
unsigned int r_type,
const elfcpp::Sym<size, big_endian>&);
inline bool
global_reloc_may_be_function_pointer(Symbol_table* , Layout* ,
Target_aarch64<size, big_endian>* ,
Sized_relobj_file<size, big_endian>* ,
unsigned int ,
Output_section* ,
const elfcpp::Rela<size, big_endian>& ,
unsigned int r_type,
Symbol* gsym);
private:
static void
unsupported_reloc_local(Sized_relobj_file<size, big_endian>*,
unsigned int r_type);
static void
unsupported_reloc_global(Sized_relobj_file<size, big_endian>*,
unsigned int r_type, Symbol*);
inline bool
possible_function_pointer_reloc(unsigned int r_type);
void
check_non_pic(Relobj*, unsigned int r_type);
bool
reloc_needs_plt_for_ifunc(Sized_relobj_file<size, big_endian>*,
unsigned int r_type);
// Whether we have issued an error about a non-PIC compilation.
bool issued_non_pic_error_;
};
// The class which implements relocation.
class Relocate
{
public:
Relocate()
: skip_call_tls_get_addr_(false)
{ }
~Relocate()
{ }
// Do a relocation. Return false if the caller should not issue
// any warnings about this relocation.
inline bool
relocate(const Relocate_info<size, big_endian>*, unsigned int,
Target_aarch64*, Output_section*, size_t, const unsigned char*,
const Sized_symbol<size>*, const Symbol_value<size>*,
unsigned char*, typename elfcpp::Elf_types<size>::Elf_Addr,
section_size_type);
private:
inline typename AArch64_relocate_functions<size, big_endian>::Status
relocate_tls(const Relocate_info<size, big_endian>*,
Target_aarch64<size, big_endian>*,
size_t,
const elfcpp::Rela<size, big_endian>&,
unsigned int r_type, const Sized_symbol<size>*,
const Symbol_value<size>*,
unsigned char*,
typename elfcpp::Elf_types<size>::Elf_Addr);
inline typename AArch64_relocate_functions<size, big_endian>::Status
tls_gd_to_le(
const Relocate_info<size, big_endian>*,
Target_aarch64<size, big_endian>*,
const elfcpp::Rela<size, big_endian>&,
unsigned int,
unsigned char*,
const Symbol_value<size>*);
inline typename AArch64_relocate_functions<size, big_endian>::Status
tls_ld_to_le(
const Relocate_info<size, big_endian>*,
Target_aarch64<size, big_endian>*,
const elfcpp::Rela<size, big_endian>&,
unsigned int,
unsigned char*,
const Symbol_value<size>*);
inline typename AArch64_relocate_functions<size, big_endian>::Status
tls_ie_to_le(
const Relocate_info<size, big_endian>*,
Target_aarch64<size, big_endian>*,
const elfcpp::Rela<size, big_endian>&,
unsigned int,
unsigned char*,
const Symbol_value<size>*);
inline typename AArch64_relocate_functions<size, big_endian>::Status
tls_desc_gd_to_le(
const Relocate_info<size, big_endian>*,
Target_aarch64<size, big_endian>*,
const elfcpp::Rela<size, big_endian>&,
unsigned int,
unsigned char*,
const Symbol_value<size>*);
inline typename AArch64_relocate_functions<size, big_endian>::Status
tls_desc_gd_to_ie(
const Relocate_info<size, big_endian>*,
Target_aarch64<size, big_endian>*,
const elfcpp::Rela<size, big_endian>&,
unsigned int,
unsigned char*,
const Symbol_value<size>*,
typename elfcpp::Elf_types<size>::Elf_Addr,
typename elfcpp::Elf_types<size>::Elf_Addr);
bool skip_call_tls_get_addr_;
}; // End of class Relocate
// A class which returns the size required for a relocation type,
// used while scanning relocs during a relocatable link.
class Relocatable_size_for_reloc
{
public:
unsigned int
get_size_for_reloc(unsigned int, Relobj*);
};
// Adjust TLS relocation type based on the options and whether this
// is a local symbol.
static tls::Tls_optimization
optimize_tls_reloc(bool is_final, int r_type);
// Get the GOT section, creating it if necessary.
Output_data_got_aarch64<size, big_endian>*
got_section(Symbol_table*, Layout*);
// Get the GOT PLT section.
Output_data_space*
got_plt_section() const
{
gold_assert(this->got_plt_ != NULL);
return this->got_plt_;
}
// Get the GOT section for TLSDESC entries.
Output_data_got<size, big_endian>*
got_tlsdesc_section() const
{
gold_assert(this->got_tlsdesc_ != NULL);
return this->got_tlsdesc_;
}
// Create the PLT section.
void
make_plt_section(Symbol_table* symtab, Layout* layout);
// Create a PLT entry for a global symbol.
void
make_plt_entry(Symbol_table*, Layout*, Symbol*);
// Create a PLT entry for a local STT_GNU_IFUNC symbol.
void
make_local_ifunc_plt_entry(Symbol_table*, Layout*,
Sized_relobj_file<size, big_endian>* relobj,
unsigned int local_sym_index);
// Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
void
define_tls_base_symbol(Symbol_table*, Layout*);
// Create the reserved PLT and GOT entries for the TLS descriptor resolver.
void
reserve_tlsdesc_entries(Symbol_table* symtab, Layout* layout);
// Create a GOT entry for the TLS module index.
unsigned int
got_mod_index_entry(Symbol_table* symtab, Layout* layout,
Sized_relobj_file<size, big_endian>* object);
// Get the PLT section.
Output_data_plt_aarch64<size, big_endian>*
plt_section() const
{
gold_assert(this->plt_ != NULL);
return this->plt_;
}
// Helper method to create erratum stubs for ST_E_843419 and ST_E_835769. For
// ST_E_843419, we need an additional field for adrp offset.
void create_erratum_stub(
AArch64_relobj<size, big_endian>* relobj,
unsigned int shndx,
section_size_type erratum_insn_offset,
Address erratum_address,
typename Insn_utilities::Insntype erratum_insn,
int erratum_type,
unsigned int e843419_adrp_offset=0);
// Return whether this is a 3-insn erratum sequence.
bool is_erratum_843419_sequence(
typename elfcpp::Swap<32,big_endian>::Valtype insn1,
typename elfcpp::Swap<32,big_endian>::Valtype insn2,
typename elfcpp::Swap<32,big_endian>::Valtype insn3);
// Return whether this is a 835769 sequence.
// (Similarly implemented as in elfnn-aarch64.c.)
bool is_erratum_835769_sequence(
typename elfcpp::Swap<32,big_endian>::Valtype,
typename elfcpp::Swap<32,big_endian>::Valtype);
// Get the dynamic reloc section, creating it if necessary.
Reloc_section*
rela_dyn_section(Layout*);
// Get the section to use for TLSDESC relocations.
Reloc_section*
rela_tlsdesc_section(Layout*) const;
// Get the section to use for IRELATIVE relocations.
Reloc_section*
rela_irelative_section(Layout*);
// Add a potential copy relocation.
void
copy_reloc(Symbol_table* symtab, Layout* layout,
Sized_relobj_file<size, big_endian>* object,
unsigned int shndx, Output_section* output_section,
Symbol* sym, const elfcpp::Rela<size, big_endian>& reloc)
{
unsigned int r_type = elfcpp::elf_r_type<size>(reloc.get_r_info());
this->copy_relocs_.copy_reloc(symtab, layout,
symtab->get_sized_symbol<size>(sym),
object, shndx, output_section,
r_type, reloc.get_r_offset(),
reloc.get_r_addend(),
this->rela_dyn_section(layout));
}
// Information about this specific target which we pass to the
// general Target structure.
static const Target::Target_info aarch64_info;
// The types of GOT entries needed for this platform.
// These values are exposed to the ABI in an incremental link.
// Do not renumber existing values without changing the version
// number of the .gnu_incremental_inputs section.
enum Got_type
{
GOT_TYPE_STANDARD = 0, // GOT entry for a regular symbol
GOT_TYPE_TLS_OFFSET = 1, // GOT entry for TLS offset
GOT_TYPE_TLS_PAIR = 2, // GOT entry for TLS module/offset pair
GOT_TYPE_TLS_DESC = 3 // GOT entry for TLS_DESC pair
};
// This type is used as the argument to the target specific
// relocation routines. The only target specific reloc is
// R_AARCh64_TLSDESC against a local symbol.
struct Tlsdesc_info
{
Tlsdesc_info(Sized_relobj_file<size, big_endian>* a_object,
unsigned int a_r_sym)
: object(a_object), r_sym(a_r_sym)
{ }
// The object in which the local symbol is defined.
Sized_relobj_file<size, big_endian>* object;
// The local symbol index in the object.
unsigned int r_sym;
};
// The GOT section.
Output_data_got_aarch64<size, big_endian>* got_;
// The PLT section.
Output_data_plt_aarch64<size, big_endian>* plt_;
// The GOT PLT section.
Output_data_space* got_plt_;
// The GOT section for IRELATIVE relocations.
Output_data_space* got_irelative_;
// The GOT section for TLSDESC relocations.
Output_data_got<size, big_endian>* got_tlsdesc_;
// The _GLOBAL_OFFSET_TABLE_ symbol.
Symbol* global_offset_table_;
// The dynamic reloc section.
Reloc_section* rela_dyn_;
// The section to use for IRELATIVE relocs.
Reloc_section* rela_irelative_;
// Relocs saved to avoid a COPY reloc.
Copy_relocs<elfcpp::SHT_RELA, size, big_endian> copy_relocs_;
// Offset of the GOT entry for the TLS module index.
unsigned int got_mod_index_offset_;
// We handle R_AARCH64_TLSDESC against a local symbol as a target
// specific relocation. Here we store the object and local symbol
// index for the relocation.
std::vector<Tlsdesc_info> tlsdesc_reloc_info_;
// True if the _TLS_MODULE_BASE_ symbol has been defined.
bool tls_base_symbol_defined_;
// List of stub_tables
Stub_table_list stub_tables_;
// Actual stub group size
section_size_type stub_group_size_;
AArch64_input_section_map aarch64_input_section_map_;
}; // End of Target_aarch64
template<>
const Target::Target_info Target_aarch64<64, false>::aarch64_info =
{
64, // size
false, // is_big_endian
elfcpp::EM_AARCH64, // machine_code
false, // has_make_symbol
false, // has_resolve
false, // has_code_fill
true, // is_default_stack_executable
true, // can_icf_inline_merge_sections
'\0', // wrap_char
"/lib/ld.so.1", // program interpreter
0x400000, // default_text_segment_address
0x10000, // abi_pagesize (overridable by -z max-page-size)
0x1000, // common_pagesize (overridable by -z common-page-size)
false, // isolate_execinstr
0, // rosegment_gap
elfcpp::SHN_UNDEF, // small_common_shndx
elfcpp::SHN_UNDEF, // large_common_shndx
0, // small_common_section_flags
0, // large_common_section_flags
NULL, // attributes_section
NULL, // attributes_vendor
"_start", // entry_symbol_name
32, // hash_entry_size
};
template<>
const Target::Target_info Target_aarch64<32, false>::aarch64_info =
{
32, // size
false, // is_big_endian
elfcpp::EM_AARCH64, // machine_code
false, // has_make_symbol
false, // has_resolve
false, // has_code_fill
true, // is_default_stack_executable
false, // can_icf_inline_merge_sections
'\0', // wrap_char
"/lib/ld.so.1", // program interpreter
0x400000, // default_text_segment_address
0x10000, // abi_pagesize (overridable by -z max-page-size)
0x1000, // common_pagesize (overridable by -z common-page-size)
false, // isolate_execinstr
0, // rosegment_gap
elfcpp::SHN_UNDEF, // small_common_shndx
elfcpp::SHN_UNDEF, // large_common_shndx
0, // small_common_section_flags
0, // large_common_section_flags
NULL, // attributes_section
NULL, // attributes_vendor
"_start", // entry_symbol_name
32, // hash_entry_size
};
template<>
const Target::Target_info Target_aarch64<64, true>::aarch64_info =
{
64, // size
true, // is_big_endian
elfcpp::EM_AARCH64, // machine_code
false, // has_make_symbol
false, // has_resolve
false, // has_code_fill
true, // is_default_stack_executable
true, // can_icf_inline_merge_sections
'\0', // wrap_char
"/lib/ld.so.1", // program interpreter
0x400000, // default_text_segment_address
0x10000, // abi_pagesize (overridable by -z max-page-size)
0x1000, // common_pagesize (overridable by -z common-page-size)
false, // isolate_execinstr
0, // rosegment_gap
elfcpp::SHN_UNDEF, // small_common_shndx
elfcpp::SHN_UNDEF, // large_common_shndx
0, // small_common_section_flags
0, // large_common_section_flags
NULL, // attributes_section
NULL, // attributes_vendor
"_start", // entry_symbol_name
32, // hash_entry_size
};
template<>
const Target::Target_info Target_aarch64<32, true>::aarch64_info =
{
32, // size
true, // is_big_endian
elfcpp::EM_AARCH64, // machine_code
false, // has_make_symbol
false, // has_resolve
false, // has_code_fill
true, // is_default_stack_executable
false, // can_icf_inline_merge_sections
'\0', // wrap_char
"/lib/ld.so.1", // program interpreter
0x400000, // default_text_segment_address
0x10000, // abi_pagesize (overridable by -z max-page-size)
0x1000, // common_pagesize (overridable by -z common-page-size)
false, // isolate_execinstr
0, // rosegment_gap
elfcpp::SHN_UNDEF, // small_common_shndx
elfcpp::SHN_UNDEF, // large_common_shndx
0, // small_common_section_flags
0, // large_common_section_flags
NULL, // attributes_section
NULL, // attributes_vendor
"_start", // entry_symbol_name
32, // hash_entry_size
};
// Get the GOT section, creating it if necessary.
template<int size, bool big_endian>
Output_data_got_aarch64<size, big_endian>*
Target_aarch64<size, big_endian>::got_section(Symbol_table* symtab,
Layout* layout)
{
if (this->got_ == NULL)
{
gold_assert(symtab != NULL && layout != NULL);
// When using -z now, we can treat .got.plt as a relro section.
// Without -z now, it is modified after program startup by lazy
// PLT relocations.
bool is_got_plt_relro = parameters->options().now();
Output_section_order got_order = (is_got_plt_relro
? ORDER_RELRO
: ORDER_RELRO_LAST);
Output_section_order got_plt_order = (is_got_plt_relro
? ORDER_RELRO
: ORDER_NON_RELRO_FIRST);
// Layout of .got and .got.plt sections.
// .got[0] &_DYNAMIC <-_GLOBAL_OFFSET_TABLE_
// ...
// .gotplt[0] reserved for ld.so (&linkmap) <--DT_PLTGOT
// .gotplt[1] reserved for ld.so (resolver)
// .gotplt[2] reserved
// Generate .got section.
this->got_ = new Output_data_got_aarch64<size, big_endian>(symtab,
layout);
layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
(elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE),
this->got_, got_order, true);
// The first word of GOT is reserved for the address of .dynamic.
// We put 0 here now. The value will be replaced later in
// Output_data_got_aarch64::do_write.
this->got_->add_constant(0);
// Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT.
// _GLOBAL_OFFSET_TABLE_ value points to the start of the .got section,
// even if there is a .got.plt section.
this->global_offset_table_ =
symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL,
Symbol_table::PREDEFINED,
this->got_,
0, 0, elfcpp::STT_OBJECT,
elfcpp::STB_LOCAL,
elfcpp::STV_HIDDEN, 0,
false, false);
// Generate .got.plt section.
this->got_plt_ = new Output_data_space(size / 8, "** GOT PLT");
layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
(elfcpp::SHF_ALLOC
| elfcpp::SHF_WRITE),
this->got_plt_, got_plt_order,
is_got_plt_relro);
// The first three entries are reserved.
this->got_plt_->set_current_data_size(
AARCH64_GOTPLT_RESERVE_COUNT * (size / 8));
// If there are any IRELATIVE relocations, they get GOT entries
// in .got.plt after the jump slot entries.
this->got_irelative_ = new Output_data_space(size / 8,
"** GOT IRELATIVE PLT");
layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
(elfcpp::SHF_ALLOC
| elfcpp::SHF_WRITE),
this->got_irelative_,
got_plt_order,
is_got_plt_relro);
// If there are any TLSDESC relocations, they get GOT entries in
// .got.plt after the jump slot and IRELATIVE entries.
this->got_tlsdesc_ = new Output_data_got<size, big_endian>();
layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
(elfcpp::SHF_ALLOC
| elfcpp::SHF_WRITE),
this->got_tlsdesc_,
got_plt_order,
is_got_plt_relro);
if (!is_got_plt_relro)
{
// Those bytes can go into the relro segment.
layout->increase_relro(
AARCH64_GOTPLT_RESERVE_COUNT * (size / 8));
}
}
return this->got_;
}
// Get the dynamic reloc section, creating it if necessary.
template<int size, bool big_endian>
typename Target_aarch64<size, big_endian>::Reloc_section*
Target_aarch64<size, big_endian>::rela_dyn_section(Layout* layout)
{
if (this->rela_dyn_ == NULL)
{
gold_assert(layout != NULL);
this->rela_dyn_ = new Reloc_section(parameters->options().combreloc());
layout->add_output_section_data(".rela.dyn", elfcpp::SHT_RELA,
elfcpp::SHF_ALLOC, this->rela_dyn_,
ORDER_DYNAMIC_RELOCS, false);
}
return this->rela_dyn_;
}
// Get the section to use for IRELATIVE relocs, creating it if
// necessary. These go in .rela.dyn, but only after all other dynamic
// relocations. They need to follow the other dynamic relocations so
// that they can refer to global variables initialized by those
// relocs.
template<int size, bool big_endian>
typename Target_aarch64<size, big_endian>::Reloc_section*
Target_aarch64<size, big_endian>::rela_irelative_section(Layout* layout)
{
if (this->rela_irelative_ == NULL)
{
// Make sure we have already created the dynamic reloc section.
this->rela_dyn_section(layout);
this->rela_irelative_ = new Reloc_section(false);
layout->add_output_section_data(".rela.dyn", elfcpp::SHT_RELA,
elfcpp::SHF_ALLOC, this->rela_irelative_,
ORDER_DYNAMIC_RELOCS, false);
gold_assert(this->rela_dyn_->output_section()
== this->rela_irelative_->output_section());
}
return this->rela_irelative_;
}
// do_make_elf_object to override the same function in the base class. We need
// to use a target-specific sub-class of Sized_relobj_file<size, big_endian> to
// store backend specific information. Hence we need to have our own ELF object
// creation.
template<int size, bool big_endian>
Object*
Target_aarch64<size, big_endian>::do_make_elf_object(
const std::string& name,
Input_file* input_file,
off_t offset, const elfcpp::Ehdr<size, big_endian>& ehdr)
{
int et = ehdr.get_e_type();
// ET_EXEC files are valid input for --just-symbols/-R,
// and we treat them as relocatable objects.
if (et == elfcpp::ET_EXEC && input_file->just_symbols())
return Sized_target<size, big_endian>::do_make_elf_object(
name, input_file, offset, ehdr);
else if (et == elfcpp::ET_REL)
{
AArch64_relobj<size, big_endian>* obj =
new AArch64_relobj<size, big_endian>(name, input_file, offset, ehdr);
obj->setup();
return obj;
}
else if (et == elfcpp::ET_DYN)
{
// Keep base implementation.
Sized_dynobj<size, big_endian>* obj =
new Sized_dynobj<size, big_endian>(name, input_file, offset, ehdr);
obj->setup();
return obj;
}
else
{
gold_error(_("%s: unsupported ELF file type %d"),
name.c_str(), et);
return NULL;
}
}
// Scan a relocation for stub generation.
template<int size, bool big_endian>
void
Target_aarch64<size, big_endian>::scan_reloc_for_stub(
const Relocate_info<size, big_endian>* relinfo,
unsigned int r_type,
const Sized_symbol<size>* gsym,
unsigned int r_sym,
const Symbol_value<size>* psymval,
typename elfcpp::Elf_types<size>::Elf_Swxword addend,
Address address)
{
const AArch64_relobj<size, big_endian>* aarch64_relobj =
static_cast<AArch64_relobj<size, big_endian>*>(relinfo->object);
Symbol_value<size> symval;
if (gsym != NULL)
{
const AArch64_reloc_property* arp = aarch64_reloc_property_table->
get_reloc_property(r_type);
if (gsym->use_plt_offset(arp->reference_flags()))
{
// This uses a PLT, change the symbol value.
symval.set_output_value(this->plt_section()->address()
+ gsym->plt_offset());
psymval = &symval;
}
else if (gsym->is_undefined())
// There is no need to generate a stub symbol is undefined.
return;
}
// Get the symbol value.
typename Symbol_value<size>::Value value = psymval->value(aarch64_relobj, 0);
// Owing to pipelining, the PC relative branches below actually skip
// two instructions when the branch offset is 0.
Address destination = static_cast<Address>(-1);
switch (r_type)
{
case elfcpp::R_AARCH64_CALL26:
case elfcpp::R_AARCH64_JUMP26:
destination = value + addend;
break;
default:
gold_unreachable();
}
int stub_type = The_reloc_stub::
stub_type_for_reloc(r_type, address, destination);
if (stub_type == ST_NONE)
return;
The_stub_table* stub_table = aarch64_relobj->stub_table(relinfo->data_shndx);
gold_assert(stub_table != NULL);
The_reloc_stub_key key(stub_type, gsym, aarch64_relobj, r_sym, addend);
The_reloc_stub* stub = stub_table->find_reloc_stub(key);
if (stub == NULL)
{
stub = new The_reloc_stub(stub_type);
stub_table->add_reloc_stub(stub, key);
}
stub->set_destination_address(destination);
} // End of Target_aarch64::scan_reloc_for_stub
// This function scans a relocation section for stub generation.
// The template parameter Relocate must be a class type which provides
// a single function, relocate(), which implements the machine
// specific part of a relocation.
// BIG_ENDIAN is the endianness of the data. SH_TYPE is the section type:
// SHT_REL or SHT_RELA.
// PRELOCS points to the relocation data. RELOC_COUNT is the number
// of relocs. OUTPUT_SECTION is the output section.
// NEEDS_SPECIAL_OFFSET_HANDLING is true if input offsets need to be
// mapped to output offsets.
// VIEW is the section data, VIEW_ADDRESS is its memory address, and
// VIEW_SIZE is the size. These refer to the input section, unless
// NEEDS_SPECIAL_OFFSET_HANDLING is true, in which case they refer to
// the output section.
template<int size, bool big_endian>
template<int sh_type>
void inline
Target_aarch64<size, big_endian>::scan_reloc_section_for_stubs(
const Relocate_info<size, big_endian>* relinfo,
const unsigned char* prelocs,
size_t reloc_count,
Output_section* /*output_section*/,
bool /*needs_special_offset_handling*/,
const unsigned char* /*view*/,
Address view_address,
section_size_type)
{
typedef typename Reloc_types<sh_type,size,big_endian>::Reloc Reltype;
const int reloc_size =
Reloc_types<sh_type,size,big_endian>::reloc_size;
AArch64_relobj<size, big_endian>* object =
static_cast<AArch64_relobj<size, big_endian>*>(relinfo->object);
unsigned int local_count = object->local_symbol_count();
gold::Default_comdat_behavior default_comdat_behavior;
Comdat_behavior comdat_behavior = CB_UNDETERMINED;
for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
{
Reltype reloc(prelocs);
typename elfcpp::Elf_types<size>::Elf_WXword r_info = reloc.get_r_info();
unsigned int r_sym = elfcpp::elf_r_sym<size>(r_info);
unsigned int r_type = elfcpp::elf_r_type<size>(r_info);
if (r_type != elfcpp::R_AARCH64_CALL26
&& r_type != elfcpp::R_AARCH64_JUMP26)
continue;
section_offset_type offset =
convert_to_section_size_type(reloc.get_r_offset());
// Get the addend.
typename elfcpp::Elf_types<size>::Elf_Swxword addend =
reloc.get_r_addend();
const Sized_symbol<size>* sym;
Symbol_value<size> symval;
const Symbol_value<size> *psymval;
bool is_defined_in_discarded_section;
unsigned int shndx;
if (r_sym < local_count)
{
sym = NULL;
psymval = object->local_symbol(r_sym);
// If the local symbol belongs to a section we are discarding,
// and that section is a debug section, try to find the
// corresponding kept section and map this symbol to its
// counterpart in the kept section. The symbol must not
// correspond to a section we are folding.
bool is_ordinary;
shndx = psymval->input_shndx(&is_ordinary);
is_defined_in_discarded_section =
(is_ordinary
&& shndx != elfcpp::SHN_UNDEF
&& !object->is_section_included(shndx)
&& !relinfo->symtab->is_section_folded(object, shndx));
// We need to compute the would-be final value of this local
// symbol.
if (!is_defined_in_discarded_section)
{
typedef Sized_relobj_file<size, big_endian> ObjType;
typename ObjType::Compute_final_local_value_status status =
object->compute_final_local_value(r_sym, psymval, &symval,
relinfo->symtab);
if (status == ObjType::CFLV_OK)
{
// Currently we cannot handle a branch to a target in
// a merged section. If this is the case, issue an error
// and also free the merge symbol value.
if (!symval.has_output_value())
{
const std::string& section_name =
object->section_name(shndx);
object->error(_("cannot handle branch to local %u "
"in a merged section %s"),
r_sym, section_name.c_str());
}
psymval = &symval;
}
else
{
// We cannot determine the final value.
continue;
}
}
}
else
{
const Symbol* gsym;
gsym = object->global_symbol(r_sym);
gold_assert(gsym != NULL);
if (gsym->is_forwarder())
gsym = relinfo->symtab->resolve_forwards(gsym);
sym = static_cast<const Sized_symbol<size>*>(gsym);
if (sym->has_symtab_index() && sym->symtab_index() != -1U)
symval.set_output_symtab_index(sym->symtab_index());
else
symval.set_no_output_symtab_entry();
// We need to compute the would-be final value of this global
// symbol.
const Symbol_table* symtab = relinfo->symtab;
const Sized_symbol<size>* sized_symbol =
symtab->get_sized_symbol<size>(gsym);
Symbol_table::Compute_final_value_status status;
typename elfcpp::Elf_types<size>::Elf_Addr value =
symtab->compute_final_value<size>(sized_symbol, &status);
// Skip this if the symbol has not output section.
if (status == Symbol_table::CFVS_NO_OUTPUT_SECTION)
continue;
symval.set_output_value(value);
if (gsym->type() == elfcpp::STT_TLS)
symval.set_is_tls_symbol();
else if (gsym->type() == elfcpp::STT_GNU_IFUNC)
symval.set_is_ifunc_symbol();
psymval = &symval;
is_defined_in_discarded_section =
(gsym->is_defined_in_discarded_section()
&& gsym->is_undefined());
shndx = 0;
}
Symbol_value<size> symval2;
if (is_defined_in_discarded_section)
{
if (comdat_behavior == CB_UNDETERMINED)
{
std::string name = object->section_name(relinfo->data_shndx);
comdat_behavior = default_comdat_behavior.get(name.c_str());
}
if (comdat_behavior == CB_PRETEND)
{
bool found;
typename elfcpp::Elf_types<size>::Elf_Addr value =
object->map_to_kept_section(shndx, &found);
if (found)
symval2.set_output_value(value + psymval->input_value());
else
symval2.set_output_value(0);
}
else
{
if (comdat_behavior == CB_WARNING)
gold_warning_at_location(relinfo, i, offset,
_("relocation refers to discarded "
"section"));
symval2.set_output_value(0);
}
symval2.set_no_output_symtab_entry();
psymval = &symval2;
}
// If symbol is a section symbol, we don't know the actual type of
// destination. Give up.
if (psymval->is_section_symbol())
continue;
this->scan_reloc_for_stub(relinfo, r_type, sym, r_sym, psymval,
addend, view_address + offset);
} // End of iterating relocs in a section
} // End of Target_aarch64::scan_reloc_section_for_stubs
// Scan an input section for stub generation.
template<int size, bool big_endian>
void
Target_aarch64<size, big_endian>::scan_section_for_stubs(
const Relocate_info<size, big_endian>* relinfo,
unsigned int sh_type,
const unsigned char* prelocs,
size_t reloc_count,
Output_section* output_section,
bool needs_special_offset_handling,
const unsigned char* view,
Address view_address,
section_size_type view_size)
{
gold_assert(sh_type == elfcpp::SHT_RELA);
this->scan_reloc_section_for_stubs<elfcpp::SHT_RELA>(
relinfo,
prelocs,
reloc_count,
output_section,
needs_special_offset_handling,
view,
view_address,
view_size);
}
// Relocate a single stub.
template<int size, bool big_endian>
void Target_aarch64<size, big_endian>::
relocate_stub(The_reloc_stub* stub,
const The_relocate_info*,
Output_section*,
unsigned char* view,
Address address,
section_size_type)
{
typedef AArch64_relocate_functions<size, big_endian> The_reloc_functions;
typedef typename The_reloc_functions::Status The_reloc_functions_status;
typedef typename elfcpp::Swap<32,big_endian>::Valtype Insntype;
Insntype* ip = reinterpret_cast<Insntype*>(view);
int insn_number = stub->insn_num();
const uint32_t* insns = stub->insns();
// Check the insns are really those stub insns.
for (int i = 0; i < insn_number; ++i)
{
Insntype insn = elfcpp::Swap<32,big_endian>::readval(ip + i);
gold_assert(((uint32_t)insn == insns[i]));
}
Address dest = stub->destination_address();
switch(stub->type())
{
case ST_ADRP_BRANCH:
{
// 1st reloc is ADR_PREL_PG_HI21
The_reloc_functions_status status =
The_reloc_functions::adrp(view, dest, address);
// An error should never arise in the above step. If so, please
// check 'aarch64_valid_for_adrp_p'.
gold_assert(status == The_reloc_functions::STATUS_OKAY);
// 2nd reloc is ADD_ABS_LO12_NC
const AArch64_reloc_property* arp =
aarch64_reloc_property_table->get_reloc_property(
elfcpp::R_AARCH64_ADD_ABS_LO12_NC);
gold_assert(arp != NULL);
status = The_reloc_functions::template
rela_general<32>(view + 4, dest, 0, arp);
// An error should never arise, it is an "_NC" relocation.
gold_assert(status == The_reloc_functions::STATUS_OKAY);
}
break;
case ST_LONG_BRANCH_ABS:
// 1st reloc is R_AARCH64_PREL64, at offset 8
elfcpp::Swap<64,big_endian>::writeval(view + 8, dest);
break;
case ST_LONG_BRANCH_PCREL:
{
// "PC" calculation is the 2nd insn in the stub.
uint64_t offset = dest - (address + 4);
// Offset is placed at offset 4 and 5.
elfcpp::Swap<64,big_endian>::writeval(view + 16, offset);
}
break;
default:
gold_unreachable();
}
}
// A class to handle the PLT data.
// This is an abstract base class that handles most of the linker details
// but does not know the actual contents of PLT entries. The derived
// classes below fill in those details.
template<int size, bool big_endian>
class Output_data_plt_aarch64 : public Output_section_data
{
public:
typedef Output_data_reloc<elfcpp::SHT_RELA, true, size, big_endian>
Reloc_section;
typedef typename elfcpp::Elf_types<size>::Elf_Addr Address;
Output_data_plt_aarch64(Layout* layout,
uint64_t addralign,
Output_data_got_aarch64<size, big_endian>* got,
Output_data_space* got_plt,
Output_data_space* got_irelative)
: Output_section_data(addralign), tlsdesc_rel_(NULL), irelative_rel_(NULL),
got_(got), got_plt_(got_plt), got_irelative_(got_irelative),
count_(0), irelative_count_(0), tlsdesc_got_offset_(-1U)
{ this->init(layout); }
// Initialize the PLT section.
void
init(Layout* layout);
// Add an entry to the PLT.
void
add_entry(Symbol_table*, Layout*, Symbol* gsym);
// Add an entry to the PLT for a local STT_GNU_IFUNC symbol.
unsigned int
add_local_ifunc_entry(Symbol_table* symtab, Layout*,
Sized_relobj_file<size, big_endian>* relobj,
unsigned int local_sym_index);
// Add the relocation for a PLT entry.
void
add_relocation(Symbol_table*, Layout*, Symbol* gsym,
unsigned int got_offset);
// Add the reserved TLSDESC_PLT entry to the PLT.
void
reserve_tlsdesc_entry(unsigned int got_offset)
{ this->tlsdesc_got_offset_ = got_offset; }
// Return true if a TLSDESC_PLT entry has been reserved.
bool
has_tlsdesc_entry() const
{ return this->tlsdesc_got_offset_ != -1U; }
// Return the GOT offset for the reserved TLSDESC_PLT entry.
unsigned int
get_tlsdesc_got_offset() const
{ return this->tlsdesc_got_offset_; }
// Return the PLT offset of the reserved TLSDESC_PLT entry.
unsigned int
get_tlsdesc_plt_offset() const
{
return (this->first_plt_entry_offset() +
(this->count_ + this->irelative_count_)
* this->get_plt_entry_size());
}
// Return the .rela.plt section data.
Reloc_section*
rela_plt()
{ return this->rel_; }
// Return where the TLSDESC relocations should go.
Reloc_section*
rela_tlsdesc(Layout*);
// Return where the IRELATIVE relocations should go in the PLT
// relocations.
Reloc_section*
rela_irelative(Symbol_table*, Layout*);
// Return whether we created a section for IRELATIVE relocations.
bool
has_irelative_section() const
{ return this->irelative_rel_ != NULL; }
// Return the number of PLT entries.
unsigned int
entry_count() const
{ return this->count_ + this->irelative_count_; }
// Return the offset of the first non-reserved PLT entry.
unsigned int
first_plt_entry_offset() const
{ return this->do_first_plt_entry_offset(); }
// Return the size of a PLT entry.
unsigned int
get_plt_entry_size() const
{ return this->do_get_plt_entry_size(); }
// Return the reserved tlsdesc entry size.
unsigned int
get_plt_tlsdesc_entry_size() const
{ return this->do_get_plt_tlsdesc_entry_size(); }
// Return the PLT address to use for a global symbol.
uint64_t
address_for_global(const Symbol*);
// Return the PLT address to use for a local symbol.
uint64_t
address_for_local(const Relobj*, unsigned int symndx);
protected:
// Fill in the first PLT entry.
void
fill_first_plt_entry(unsigned char* pov,
Address got_address,
Address plt_address)
{ this->do_fill_first_plt_entry(pov, got_address, plt_address); }
// Fill in a normal PLT entry.
void
fill_plt_entry(unsigned char* pov,
Address got_address,
Address plt_address,
unsigned int got_offset,
unsigned int plt_offset)
{
this->do_fill_plt_entry(pov, got_address, plt_address,
got_offset, plt_offset);
}
// Fill in the reserved TLSDESC PLT entry.
void
fill_tlsdesc_entry(unsigned char* pov,
Address gotplt_address,
Address plt_address,
Address got_base,
unsigned int tlsdesc_got_offset,
unsigned int plt_offset)
{
this->do_fill_tlsdesc_entry(pov, gotplt_address, plt_address, got_base,
tlsdesc_got_offset, plt_offset);
}
virtual unsigned int
do_first_plt_entry_offset() const = 0;
virtual unsigned int
do_get_plt_entry_size() const = 0;
virtual unsigned int
do_get_plt_tlsdesc_entry_size() const = 0;
virtual void
do_fill_first_plt_entry(unsigned char* pov,
Address got_addr,
Address plt_addr) = 0;
virtual void
do_fill_plt_entry(unsigned char* pov,
Address got_address,
Address plt_address,
unsigned int got_offset,
unsigned int plt_offset) = 0;
virtual void
do_fill_tlsdesc_entry(unsigned char* pov,
Address gotplt_address,
Address plt_address,
Address got_base,
unsigned int tlsdesc_got_offset,
unsigned int plt_offset) = 0;
void
do_adjust_output_section(Output_section* os);
// Write to a map file.
void
do_print_to_mapfile(Mapfile* mapfile) const
{ mapfile->print_output_data(this, _("** PLT")); }
private:
// Set the final size.
void
set_final_data_size();
// Write out the PLT data.
void
do_write(Output_file*);
// The reloc section.
Reloc_section* rel_;
// The TLSDESC relocs, if necessary. These must follow the regular
// PLT relocs.
Reloc_section* tlsdesc_rel_;
// The IRELATIVE relocs, if necessary. These must follow the
// regular PLT relocations.
Reloc_section* irelative_rel_;
// The .got section.
Output_data_got_aarch64<size, big_endian>* got_;
// The .got.plt section.
Output_data_space* got_plt_;
// The part of the .got.plt section used for IRELATIVE relocs.
Output_data_space* got_irelative_;
// The number of PLT entries.
unsigned int count_;
// Number of PLT entries with R_AARCH64_IRELATIVE relocs. These
// follow the regular PLT entries.
unsigned int irelative_count_;
// GOT offset of the reserved TLSDESC_GOT entry for the lazy trampoline.
// Communicated to the loader via DT_TLSDESC_GOT. The magic value -1
// indicates an offset is not allocated.
unsigned int tlsdesc_got_offset_;
};
// Initialize the PLT section.
template<int size, bool big_endian>
void
Output_data_plt_aarch64<size, big_endian>::init(Layout* layout)
{
this->rel_ = new Reloc_section(false);
layout->add_output_section_data(".rela.plt", elfcpp::SHT_RELA,
elfcpp::SHF_ALLOC, this->rel_,
ORDER_DYNAMIC_PLT_RELOCS, false);
}
template<int size, bool big_endian>
void
Output_data_plt_aarch64<size, big_endian>::do_adjust_output_section(
Output_section* os)
{
os->set_entsize(this->get_plt_entry_size());
}
// Add an entry to the PLT.
template<int size, bool big_endian>
void
Output_data_plt_aarch64<size, big_endian>::add_entry(Symbol_table* symtab,
Layout* layout, Symbol* gsym)
{
gold_assert(!gsym->has_plt_offset());
unsigned int* pcount;
unsigned int plt_reserved;
Output_section_data_build* got;
if (gsym->type() == elfcpp::STT_GNU_IFUNC
&& gsym->can_use_relative_reloc(false))
{
pcount = &this->irelative_count_;
plt_reserved = 0;
got = this->got_irelative_;
}
else
{
pcount = &this->count_;
plt_reserved = this->first_plt_entry_offset();
got = this->got_plt_;
}
gsym->set_plt_offset((*pcount) * this->get_plt_entry_size()
+ plt_reserved);
++*pcount;
section_offset_type got_offset = got->current_data_size();
// Every PLT entry needs a GOT entry which points back to the PLT
// entry (this will be changed by the dynamic linker, normally
// lazily when the function is called).
got->set_current_data_size(got_offset + size / 8);
// Every PLT entry needs a reloc.
this->add_relocation(symtab, layout, gsym, got_offset);
// Note that we don't need to save the symbol. The contents of the
// PLT are independent of which symbols are used. The symbols only
// appear in the relocations.
}
// Add an entry to the PLT for a local STT_GNU_IFUNC symbol. Return
// the PLT offset.
template<int size, bool big_endian>
unsigned int
Output_data_plt_aarch64<size, big_endian>::add_local_ifunc_entry(
Symbol_table* symtab,
Layout* layout,
Sized_relobj_file<size, big_endian>* relobj,
unsigned int local_sym_index)
{
unsigned int plt_offset = this->irelative_count_ * this->get_plt_entry_size();
++this->irelative_count_;
section_offset_type got_offset = this->got_irelative_->current_data_size();
// Every PLT entry needs a GOT entry which points back to the PLT
// entry.
this->got_irelative_->set_current_data_size(got_offset + size / 8);
// Every PLT entry needs a reloc.
Reloc_section* rela = this->rela_irelative(symtab, layout);
rela->add_symbolless_local_addend(relobj, local_sym_index,
elfcpp::R_AARCH64_IRELATIVE,
this->got_irelative_, got_offset, 0);
return plt_offset;
}
// Add the relocation for a PLT entry.
template<int size, bool big_endian>
void
Output_data_plt_aarch64<size, big_endian>::add_relocation(
Symbol_table* symtab, Layout* layout, Symbol* gsym, unsigned int got_offset)
{
if (gsym->type() == elfcpp::STT_GNU_IFUNC
&& gsym->can_use_relative_reloc(false))
{
Reloc_section* rela = this->rela_irelative(symtab, layout);
rela->add_symbolless_global_addend(gsym, elfcpp::R_AARCH64_IRELATIVE,
this->got_irelative_, got_offset, 0);
}
else
{
gsym->set_needs_dynsym_entry();
this->rel_->add_global(gsym, elfcpp::R_AARCH64_JUMP_SLOT, this->got_plt_,
got_offset, 0);
}
}
// Return where the TLSDESC relocations should go, creating it if
// necessary. These follow the JUMP_SLOT relocations.
template<int size, bool big_endian>
typename Output_data_plt_aarch64<size, big_endian>::Reloc_section*
Output_data_plt_aarch64<size, big_endian>::rela_tlsdesc(Layout* layout)
{
if (this->tlsdesc_rel_ == NULL)
{
this->tlsdesc_rel_ = new Reloc_section(false);
layout->add_output_section_data(".rela.plt", elfcpp::SHT_RELA,
elfcpp::SHF_ALLOC, this->tlsdesc_rel_,
ORDER_DYNAMIC_PLT_RELOCS, false);
gold_assert(this->tlsdesc_rel_->output_section()
== this->rel_->output_section());
}
return this->tlsdesc_rel_;
}
// Return where the IRELATIVE relocations should go in the PLT. These
// follow the JUMP_SLOT and the TLSDESC relocations.
template<int size, bool big_endian>
typename Output_data_plt_aarch64<size, big_endian>::Reloc_section*
Output_data_plt_aarch64<size, big_endian>::rela_irelative(Symbol_table* symtab,
Layout* layout)
{
if (this->irelative_rel_ == NULL)
{
// Make sure we have a place for the TLSDESC relocations, in
// case we see any later on.
this->rela_tlsdesc(layout);
this->irelative_rel_ = new Reloc_section(false);
layout->add_output_section_data(".rela.plt", elfcpp::SHT_RELA,
elfcpp::SHF_ALLOC, this->irelative_rel_,
ORDER_DYNAMIC_PLT_RELOCS, false);
gold_assert(this->irelative_rel_->output_section()
== this->rel_->output_section());
if (parameters->doing_static_link())
{
// A statically linked executable will only have a .rela.plt
// section to hold R_AARCH64_IRELATIVE relocs for
// STT_GNU_IFUNC symbols. The library will use these
// symbols to locate the IRELATIVE relocs at program startup
// time.
symtab->define_in_output_data("__rela_iplt_start", NULL,
Symbol_table::PREDEFINED,
this->irelative_rel_, 0, 0,
elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL,
elfcpp::STV_HIDDEN, 0, false, true);
symtab->define_in_output_data("__rela_iplt_end", NULL,
Symbol_table::PREDEFINED,
this->irelative_rel_, 0, 0,
elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL,
elfcpp::STV_HIDDEN, 0, true, true);
}
}
return this->irelative_rel_;
}
// Return the PLT address to use for a global symbol.
template<int size, bool big_endian>
uint64_t
Output_data_plt_aarch64<size, big_endian>::address_for_global(
const Symbol* gsym)
{
uint64_t offset = 0;
if (gsym->type() == elfcpp::STT_GNU_IFUNC
&& gsym->can_use_relative_reloc(false))
offset = (this->first_plt_entry_offset() +
this->count_ * this->get_plt_entry_size());
return this->address() + offset + gsym->plt_offset();
}
// Return the PLT address to use for a local symbol. These are always
// IRELATIVE relocs.
template<int size, bool big_endian>
uint64_t
Output_data_plt_aarch64<size, big_endian>::address_for_local(
const Relobj* object,
unsigned int r_sym)
{
return (this->address()
+ this->first_plt_entry_offset()
+ this->count_ * this->get_plt_entry_size()
+ object->local_plt_offset(r_sym));
}
// Set the final size.
template<int size, bool big_endian>
void
Output_data_plt_aarch64<size, big_endian>::set_final_data_size()
{
unsigned int count = this->count_ + this->irelative_count_;
unsigned int extra_size = 0;
if (this->has_tlsdesc_entry())
extra_size += this->get_plt_tlsdesc_entry_size();
this->set_data_size(this->first_plt_entry_offset()
+ count * this->get_plt_entry_size()
+ extra_size);
}
template<int size, bool big_endian>
class Output_data_plt_aarch64_standard :
public Output_data_plt_aarch64<size, big_endian>
{
public:
typedef typename elfcpp::Elf_types<size>::Elf_Addr Address;
Output_data_plt_aarch64_standard(
Layout* layout,
Output_data_got_aarch64<size, big_endian>* got,
Output_data_space* got_plt,
Output_data_space* got_irelative)
: Output_data_plt_aarch64<size, big_endian>(layout,
size == 32 ? 4 : 8,
got, got_plt,
got_irelative)
{ }
protected:
// Return the offset of the first non-reserved PLT entry.
virtual unsigned int
do_first_plt_entry_offset() const
{ return this->first_plt_entry_size; }
// Return the size of a PLT entry
virtual unsigned int
do_get_plt_entry_size() const
{ return this->plt_entry_size; }
// Return the size of a tlsdesc entry
virtual unsigned int
do_get_plt_tlsdesc_entry_size() const
{ return this->plt_tlsdesc_entry_size; }
virtual void
do_fill_first_plt_entry(unsigned char* pov,
Address got_address,
Address plt_address);
virtual void
do_fill_plt_entry(unsigned char* pov,
Address got_address,
Address plt_address,
unsigned int got_offset,
unsigned int plt_offset);
virtual void
do_fill_tlsdesc_entry(unsigned char* pov,
Address gotplt_address,
Address plt_address,
Address got_base,
unsigned int tlsdesc_got_offset,
unsigned int plt_offset);
private:
// The size of the first plt entry size.
static const int first_plt_entry_size = 32;
// The size of the plt entry size.
static const int plt_entry_size = 16;
// The size of the plt tlsdesc entry size.
static const int plt_tlsdesc_entry_size = 32;
// Template for the first PLT entry.
static const uint32_t first_plt_entry[first_plt_entry_size / 4];
// Template for subsequent PLT entries.
static const uint32_t plt_entry[plt_entry_size / 4];
// The reserved TLSDESC entry in the PLT for an executable.
static const uint32_t tlsdesc_plt_entry[plt_tlsdesc_entry_size / 4];
};
// The first entry in the PLT for an executable.
template<>
const uint32_t
Output_data_plt_aarch64_standard<32, false>::
first_plt_entry[first_plt_entry_size / 4] =
{
0xa9bf7bf0, /* stp x16, x30, [sp, #-16]! */
0x90000010, /* adrp x16, PLT_GOT+0x8 */
0xb9400A11, /* ldr w17, [x16, #PLT_GOT+0x8] */
0x11002210, /* add w16, w16,#PLT_GOT+0x8 */
0xd61f0220, /* br x17 */
0xd503201f, /* nop */
0xd503201f, /* nop */
0xd503201f, /* nop */
};
template<>
const uint32_t
Output_data_plt_aarch64_standard<32, true>::
first_plt_entry[first_plt_entry_size / 4] =
{
0xa9bf7bf0, /* stp x16, x30, [sp, #-16]! */
0x90000010, /* adrp x16, PLT_GOT+0x8 */
0xb9400A11, /* ldr w17, [x16, #PLT_GOT+0x8] */
0x11002210, /* add w16, w16,#PLT_GOT+0x8 */
0xd61f0220, /* br x17 */
0xd503201f, /* nop */
0xd503201f, /* nop */
0xd503201f, /* nop */
};
template<>
const uint32_t
Output_data_plt_aarch64_standard<64, false>::
first_plt_entry[first_plt_entry_size / 4] =
{
0xa9bf7bf0, /* stp x16, x30, [sp, #-16]! */
0x90000010, /* adrp x16, PLT_GOT+16 */
0xf9400A11, /* ldr x17, [x16, #PLT_GOT+0x10] */
0x91004210, /* add x16, x16,#PLT_GOT+0x10 */
0xd61f0220, /* br x17 */
0xd503201f, /* nop */
0xd503201f, /* nop */
0xd503201f, /* nop */
};
template<>
const uint32_t
Output_data_plt_aarch64_standard<64, true>::
first_plt_entry[first_plt_entry_size / 4] =
{
0xa9bf7bf0, /* stp x16, x30, [sp, #-16]! */
0x90000010, /* adrp x16, PLT_GOT+16 */
0xf9400A11, /* ldr x17, [x16, #PLT_GOT+0x10] */
0x91004210, /* add x16, x16,#PLT_GOT+0x10 */
0xd61f0220, /* br x17 */
0xd503201f, /* nop */
0xd503201f, /* nop */
0xd503201f, /* nop */
};
template<>
const uint32_t
Output_data_plt_aarch64_standard<32, false>::
plt_entry[plt_entry_size / 4] =
{
0x90000010, /* adrp x16, PLTGOT + n * 4 */
0xb9400211, /* ldr w17, [w16, PLTGOT + n * 4] */
0x11000210, /* add w16, w16, :lo12:PLTGOT + n * 4 */
0xd61f0220, /* br x17. */
};
template<>
const uint32_t
Output_data_plt_aarch64_standard<32, true>::
plt_entry[plt_entry_size / 4] =
{
0x90000010, /* adrp x16, PLTGOT + n * 4 */
0xb9400211, /* ldr w17, [w16, PLTGOT + n * 4] */
0x11000210, /* add w16, w16, :lo12:PLTGOT + n * 4 */
0xd61f0220, /* br x17. */
};
template<>
const uint32_t
Output_data_plt_aarch64_standard<64, false>::
plt_entry[plt_entry_size / 4] =
{
0x90000010, /* adrp x16, PLTGOT + n * 8 */
0xf9400211, /* ldr x17, [x16, PLTGOT + n * 8] */
0x91000210, /* add x16, x16, :lo12:PLTGOT + n * 8 */
0xd61f0220, /* br x17. */
};
template<>
const uint32_t
Output_data_plt_aarch64_standard<64, true>::
plt_entry[plt_entry_size / 4] =
{
0x90000010, /* adrp x16, PLTGOT + n * 8 */
0xf9400211, /* ldr x17, [x16, PLTGOT + n * 8] */
0x91000210, /* add x16, x16, :lo12:PLTGOT + n * 8 */
0xd61f0220, /* br x17. */
};
template<int size, bool big_endian>
void
Output_data_plt_aarch64_standard<size, big_endian>::do_fill_first_plt_entry(
unsigned char* pov,
Address got_address,
Address plt_address)
{
// PLT0 of the small PLT looks like this in ELF64 -
// stp x16, x30, [sp, #-16]! Save the reloc and lr on stack.
// adrp x16, PLT_GOT + 16 Get the page base of the GOTPLT
// ldr x17, [x16, #:lo12:PLT_GOT+16] Load the address of the
// symbol resolver
// add x16, x16, #:lo12:PLT_GOT+16 Load the lo12 bits of the
// GOTPLT entry for this.
// br x17
// PLT0 will be slightly different in ELF32 due to different got entry
// size.
memcpy(pov, this->first_plt_entry, this->first_plt_entry_size);
Address gotplt_2nd_ent = got_address + (size / 8) * 2;
// Fill in the top 21 bits for this: ADRP x16, PLT_GOT + 8 * 2.
// ADRP: (PG(S+A)-PG(P)) >> 12) & 0x1fffff.
// FIXME: This only works for 64bit
AArch64_relocate_functions<size, big_endian>::adrp(pov + 4,
gotplt_2nd_ent, plt_address + 4);
// Fill in R_AARCH64_LDST8_LO12
elfcpp::Swap<32, big_endian>::writeval(
pov + 8,
((this->first_plt_entry[2] & 0xffc003ff)
| ((gotplt_2nd_ent & 0xff8) << 7)));
// Fill in R_AARCH64_ADD_ABS_LO12
elfcpp::Swap<32, big_endian>::writeval(
pov + 12,
((this->first_plt_entry[3] & 0xffc003ff)
| ((gotplt_2nd_ent & 0xfff) << 10)));
}
// Subsequent entries in the PLT for an executable.
// FIXME: This only works for 64bit
template<int size, bool big_endian>
void
Output_data_plt_aarch64_standard<size, big_endian>::do_fill_plt_entry(
unsigned char* pov,
Address got_address,
Address plt_address,
unsigned int got_offset,
unsigned int plt_offset)
{
memcpy(pov, this->plt_entry, this->plt_entry_size);
Address gotplt_entry_address = got_address + got_offset;
Address plt_entry_address = plt_address + plt_offset;
// Fill in R_AARCH64_PCREL_ADR_HI21
AArch64_relocate_functions<size, big_endian>::adrp(
pov,
gotplt_entry_address,
plt_entry_address);
// Fill in R_AARCH64_LDST64_ABS_LO12
elfcpp::Swap<32, big_endian>::writeval(
pov + 4,
((this->plt_entry[1] & 0xffc003ff)
| ((gotplt_entry_address & 0xff8) << 7)));
// Fill in R_AARCH64_ADD_ABS_LO12
elfcpp::Swap<32, big_endian>::writeval(
pov + 8,
((this->plt_entry[2] & 0xffc003ff)
| ((gotplt_entry_address & 0xfff) <<10)));
}
template<>
const uint32_t
Output_data_plt_aarch64_standard<32, false>::
tlsdesc_plt_entry[plt_tlsdesc_entry_size / 4] =
{
0xa9bf0fe2, /* stp x2, x3, [sp, #-16]! */
0x90000002, /* adrp x2, 0 */
0x90000003, /* adrp x3, 0 */
0xb9400042, /* ldr w2, [w2, #0] */
0x11000063, /* add w3, w3, 0 */
0xd61f0040, /* br x2 */
0xd503201f, /* nop */
0xd503201f, /* nop */
};
template<>
const uint32_t
Output_data_plt_aarch64_standard<32, true>::
tlsdesc_plt_entry[plt_tlsdesc_entry_size / 4] =
{
0xa9bf0fe2, /* stp x2, x3, [sp, #-16]! */
0x90000002, /* adrp x2, 0 */
0x90000003, /* adrp x3, 0 */
0xb9400042, /* ldr w2, [w2, #0] */
0x11000063, /* add w3, w3, 0 */
0xd61f0040, /* br x2 */
0xd503201f, /* nop */
0xd503201f, /* nop */
};
template<>
const uint32_t
Output_data_plt_aarch64_standard<64, false>::
tlsdesc_plt_entry[plt_tlsdesc_entry_size / 4] =
{
0xa9bf0fe2, /* stp x2, x3, [sp, #-16]! */
0x90000002, /* adrp x2, 0 */
0x90000003, /* adrp x3, 0 */
0xf9400042, /* ldr x2, [x2, #0] */
0x91000063, /* add x3, x3, 0 */
0xd61f0040, /* br x2 */
0xd503201f, /* nop */
0xd503201f, /* nop */
};
template<>
const uint32_t
Output_data_plt_aarch64_standard<64, true>::
tlsdesc_plt_entry[plt_tlsdesc_entry_size / 4] =
{
0xa9bf0fe2, /* stp x2, x3, [sp, #-16]! */
0x90000002, /* adrp x2, 0 */
0x90000003, /* adrp x3, 0 */
0xf9400042, /* ldr x2, [x2, #0] */
0x91000063, /* add x3, x3, 0 */
0xd61f0040, /* br x2 */
0xd503201f, /* nop */
0xd503201f, /* nop */
};
template<int size, bool big_endian>
void
Output_data_plt_aarch64_standard<size, big_endian>::do_fill_tlsdesc_entry(
unsigned char* pov,
Address gotplt_address,
Address plt_address,
Address got_base,
unsigned int tlsdesc_got_offset,
unsigned int plt_offset)
{
memcpy(pov, tlsdesc_plt_entry, plt_tlsdesc_entry_size);
// move DT_TLSDESC_GOT address into x2
// move .got.plt address into x3
Address tlsdesc_got_entry = got_base + tlsdesc_got_offset;
Address plt_entry_address = plt_address + plt_offset;
// R_AARCH64_ADR_PREL_PG_HI21
AArch64_relocate_functions<size, big_endian>::adrp(
pov + 4,
tlsdesc_got_entry,
plt_entry_address + 4);
// R_AARCH64_ADR_PREL_PG_HI21
AArch64_relocate_functions<size, big_endian>::adrp(
pov + 8,
gotplt_address,
plt_entry_address + 8);
// R_AARCH64_LDST64_ABS_LO12
elfcpp::Swap<32, big_endian>::writeval(
pov + 12,
((this->tlsdesc_plt_entry[3] & 0xffc003ff)
| ((tlsdesc_got_entry & 0xff8) << 7)));
// R_AARCH64_ADD_ABS_LO12
elfcpp::Swap<32, big_endian>::writeval(
pov + 16,
((this->tlsdesc_plt_entry[4] & 0xffc003ff)
| ((gotplt_address & 0xfff) << 10)));
}
// Write out the PLT. This uses the hand-coded instructions above,
// and adjusts them as needed. This is specified by the AMD64 ABI.
template<int size, bool big_endian>
void
Output_data_plt_aarch64<size, big_endian>::do_write(Output_file* of)
{
const off_t offset = this->offset();
const section_size_type oview_size =
convert_to_section_size_type(this->data_size());
unsigned char* const oview = of->get_output_view(offset, oview_size);
const off_t got_file_offset = this->got_plt_->offset();
gold_assert(got_file_offset + this->got_plt_->data_size()
== this->got_irelative_->offset());
const section_size_type got_size =
convert_to_section_size_type(this->got_plt_->data_size()
+ this->got_irelative_->data_size());
unsigned char* const got_view = of->get_output_view(got_file_offset,
got_size);
unsigned char* pov = oview;
// The base address of the .plt section.
typename elfcpp::Elf_types<size>::Elf_Addr plt_address = this->address();
// The base address of the PLT portion of the .got section.
typename elfcpp::Elf_types<size>::Elf_Addr gotplt_address
= this->got_plt_->address();
this->fill_first_plt_entry(pov, gotplt_address, plt_address);
pov += this->first_plt_entry_offset();
// The first three entries in .got.plt are reserved.
unsigned char* got_pov = got_view;
memset(got_pov, 0, size / 8 * AARCH64_GOTPLT_RESERVE_COUNT);
got_pov += (size / 8) * AARCH64_GOTPLT_RESERVE_COUNT;
unsigned int plt_offset = this->first_plt_entry_offset();
unsigned int got_offset = (size / 8) * AARCH64_GOTPLT_RESERVE_COUNT;
const unsigned int count = this->count_ + this->irelative_count_;
for (unsigned int plt_index = 0;
plt_index < count;
++plt_index,
pov += this->get_plt_entry_size(),
got_pov += size / 8,
plt_offset += this->get_plt_entry_size(),
got_offset += size / 8)
{
// Set and adjust the PLT entry itself.
this->fill_plt_entry(pov, gotplt_address, plt_address,
got_offset, plt_offset);
// Set the entry in the GOT, which points to plt0.
elfcpp::Swap<size, big_endian>::writeval(got_pov, plt_address);
}
if (this->has_tlsdesc_entry())
{
// Set and adjust the reserved TLSDESC PLT entry.
unsigned int tlsdesc_got_offset = this->get_tlsdesc_got_offset();
// The base address of the .base section.
typename elfcpp::Elf_types<size>::Elf_Addr got_base =
this->got_->address();
this->fill_tlsdesc_entry(pov, gotplt_address, plt_address, got_base,
tlsdesc_got_offset, plt_offset);
pov += this->get_plt_tlsdesc_entry_size();
}
gold_assert(static_cast<section_size_type>(pov - oview) == oview_size);
gold_assert(static_cast<section_size_type>(got_pov - got_view) == got_size);
of->write_output_view(offset, oview_size, oview);
of->write_output_view(got_file_offset, got_size, got_view);
}
// Telling how to update the immediate field of an instruction.
struct AArch64_howto
{
// The immediate field mask.
elfcpp::Elf_Xword dst_mask;
// The offset to apply relocation immediate
int doffset;
// The second part offset, if the immediate field has two parts.
// -1 if the immediate field has only one part.
int doffset2;
};
static const AArch64_howto aarch64_howto[AArch64_reloc_property::INST_NUM] =
{
{0, -1, -1}, // DATA
{0x1fffe0, 5, -1}, // MOVW [20:5]-imm16
{0xffffe0, 5, -1}, // LD [23:5]-imm19
{0x60ffffe0, 29, 5}, // ADR [30:29]-immlo [23:5]-immhi
{0x60ffffe0, 29, 5}, // ADRP [30:29]-immlo [23:5]-immhi
{0x3ffc00, 10, -1}, // ADD [21:10]-imm12
{0x3ffc00, 10, -1}, // LDST [21:10]-imm12
{0x7ffe0, 5, -1}, // TBZNZ [18:5]-imm14
{0xffffe0, 5, -1}, // CONDB [23:5]-imm19
{0x3ffffff, 0, -1}, // B [25:0]-imm26
{0x3ffffff, 0, -1}, // CALL [25:0]-imm26
};
// AArch64 relocate function class
template<int size, bool big_endian>
class AArch64_relocate_functions
{
public:
typedef enum
{
STATUS_OKAY, // No error during relocation.
STATUS_OVERFLOW, // Relocation overflow.
STATUS_BAD_RELOC, // Relocation cannot be applied.
} Status;
typedef AArch64_relocate_functions<size, big_endian> This;
typedef typename elfcpp::Elf_types<size>::Elf_Addr Address;
typedef Relocate_info<size, big_endian> The_relocate_info;
typedef AArch64_relobj<size, big_endian> The_aarch64_relobj;
typedef Reloc_stub<size, big_endian> The_reloc_stub;
typedef Stub_table<size, big_endian> The_stub_table;
typedef elfcpp::Rela<size, big_endian> The_rela;
typedef typename elfcpp::Swap<size, big_endian>::Valtype AArch64_valtype;
// Return the page address of the address.
// Page(address) = address & ~0xFFF
static inline AArch64_valtype
Page(Address address)
{
return (address & (~static_cast<Address>(0xFFF)));
}
private:
// Update instruction (pointed by view) with selected bits (immed).
// val = (val & ~dst_mask) | (immed << doffset)
template<int valsize>
static inline void
update_view(unsigned char* view,
AArch64_valtype immed,
elfcpp::Elf_Xword doffset,
elfcpp::Elf_Xword dst_mask)
{
typedef typename elfcpp::Swap<valsize, big_endian>::Valtype Valtype;
Valtype* wv = reinterpret_cast<Valtype*>(view);
Valtype val = elfcpp::Swap<valsize, big_endian>::readval(wv);
// Clear immediate fields.
val &= ~dst_mask;
elfcpp::Swap<valsize, big_endian>::writeval(wv,
static_cast<Valtype>(val | (immed << doffset)));
}
// Update two parts of an instruction (pointed by view) with selected
// bits (immed1 and immed2).
// val = (val & ~dst_mask) | (immed1 << doffset1) | (immed2 << doffset2)
template<int valsize>
static inline void
update_view_two_parts(
unsigned char* view,
AArch64_valtype immed1,
AArch64_valtype immed2,
elfcpp::Elf_Xword doffset1,
elfcpp::Elf_Xword doffset2,
elfcpp::Elf_Xword dst_mask)
{
typedef typename elfcpp::Swap<valsize, big_endian>::Valtype Valtype;
Valtype* wv = reinterpret_cast<Valtype*>(view);
Valtype val = elfcpp::Swap<valsize, big_endian>::readval(wv);
val &= ~dst_mask;
elfcpp::Swap<valsize, big_endian>::writeval(wv,
static_cast<Valtype>(val | (immed1 << doffset1) |
(immed2 << doffset2)));
}
// Update adr or adrp instruction with immed.
// In adr and adrp: [30:29] immlo [23:5] immhi
static inline void
update_adr(unsigned char* view, AArch64_valtype immed)
{
elfcpp::Elf_Xword dst_mask = (0x3 << 29) | (0x7ffff << 5);
This::template update_view_two_parts<32>(
view,
immed & 0x3,
(immed & 0x1ffffc) >> 2,
29,
5,
dst_mask);
}
// Update movz/movn instruction with bits immed.
// Set instruction to movz if is_movz is true, otherwise set instruction
// to movn.
static inline void
update_movnz(unsigned char* view,
AArch64_valtype immed,
bool is_movz)
{
typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
Valtype* wv = reinterpret_cast<Valtype*>(view);
Valtype val = elfcpp::Swap<32, big_endian>::readval(wv);
const elfcpp::Elf_Xword doffset =
aarch64_howto[AArch64_reloc_property::INST_MOVW].doffset;
const elfcpp::Elf_Xword dst_mask =
aarch64_howto[AArch64_reloc_property::INST_MOVW].dst_mask;
// Clear immediate fields and opc code.
val &= ~(dst_mask | (0x3 << 29));
// Set instruction to movz or movn.
// movz: [30:29] is 10 movn: [30:29] is 00
if (is_movz)
val |= (0x2 << 29);
elfcpp::Swap<32, big_endian>::writeval(wv,
static_cast<Valtype>(val | (immed << doffset)));
}
// Update selected bits in text.
template<int valsize>
static inline typename This::Status
reloc_common(unsigned char* view, Address x,
const AArch64_reloc_property* reloc_property)
{
// Select bits from X.
Address immed = reloc_property->select_x_value(x);
// Update view.
const AArch64_reloc_property::Reloc_inst inst =
reloc_property->reloc_inst();
// If it is a data relocation or instruction has 2 parts of immediate
// fields, you should not call pcrela_general.
gold_assert(aarch64_howto[inst].doffset2 == -1 &&
aarch64_howto[inst].doffset != -1);
This::template update_view<valsize>(view, immed,
aarch64_howto[inst].doffset,
aarch64_howto[inst].dst_mask);
// Do check overflow or alignment if needed.
return (reloc_property->checkup_x_value(x)
? This::STATUS_OKAY
: This::STATUS_OVERFLOW);
}
public:
// Construct a B insn. Note, although we group it here with other relocation
// operation, there is actually no 'relocation' involved here.
static inline void
construct_b(unsigned char* view, unsigned int branch_offset)
{
update_view_two_parts<32>(view, 0x05, (branch_offset >> 2),
26, 0, 0xffffffff);
}
// Do a simple rela relocation at unaligned addresses.
template<int valsize>
static inline typename This::Status
rela_ua(unsigned char* view,
const Sized_relobj_file<size, big_endian>* object,
const Symbol_value<size>* psymval,
AArch64_valtype addend,
const AArch64_reloc_property* reloc_property)
{
typedef typename elfcpp::Swap_unaligned<valsize, big_endian>::Valtype
Valtype;
typename elfcpp::Elf_types<size>::Elf_Addr x =
psymval->value(object, addend);
elfcpp::Swap_unaligned<valsize, big_endian>::writeval(view,
static_cast<Valtype>(x));
return (reloc_property->checkup_x_value(x)
? This::STATUS_OKAY
: This::STATUS_OVERFLOW);
}
// Do a simple pc-relative relocation at unaligned addresses.
template<int valsize>
static inline typename This::Status
pcrela_ua(unsigned char* view,
const Sized_relobj_file<size, big_endian>* object,
const Symbol_value<size>* psymval,
AArch64_valtype addend,
Address address,
const AArch64_reloc_property* reloc_property)
{
typedef typename elfcpp::Swap_unaligned<valsize, big_endian>::Valtype
Valtype;
Address x = psymval->value(object, addend) - address;
elfcpp::Swap_unaligned<valsize, big_endian>::writeval(view,
static_cast<Valtype>(x));
return (reloc_property->checkup_x_value(x)
? This::STATUS_OKAY
: This::STATUS_OVERFLOW);
}
// Do a simple rela relocation at aligned addresses.
template<int valsize>
static inline typename This::Status
rela(
unsigned char* view,
const Sized_relobj_file<size, big_endian>* object,
const Symbol_value<size>* psymval,
AArch64_valtype addend,
const AArch64_reloc_property* reloc_property)
{
typedef typename elfcpp::Swap<valsize, big_endian>::Valtype Valtype;
Valtype* wv = reinterpret_cast<Valtype*>(view);
Address x = psymval->value(object, addend);
elfcpp::Swap<valsize, big_endian>::writeval(wv,static_cast<Valtype>(x));
return (reloc_property->checkup_x_value(x)
? This::STATUS_OKAY
: This::STATUS_OVERFLOW);
}
// Do relocate. Update selected bits in text.
// new_val = (val & ~dst_mask) | (immed << doffset)
template<int valsize>
static inline typename This::Status
rela_general(unsigned char* view,
const Sized_relobj_file<size, big_endian>* object,
const Symbol_value<size>* psymval,
AArch64_valtype addend,
const AArch64_reloc_property* reloc_property)
{
// Calculate relocation.
Address x = psymval->value(object, addend);
return This::template reloc_common<valsize>(view, x, reloc_property);
}
// Do relocate. Update selected bits in text.
// new val = (val & ~dst_mask) | (immed << doffset)
template<int valsize>
static inline typename This::Status
rela_general(
unsigned char* view,
AArch64_valtype s,
AArch64_valtype addend,
const AArch64_reloc_property* reloc_property)
{
// Calculate relocation.
Address x = s + addend;
return This::template reloc_common<valsize>(view, x, reloc_property);
}
// Do address relative relocate. Update selected bits in text.
// new val = (val & ~dst_mask) | (immed << doffset)
template<int valsize>
static inline typename This::Status
pcrela_general(
unsigned char* view,
const Sized_relobj_file<size, big_endian>* object,
const Symbol_value<size>* psymval,
AArch64_valtype addend,
Address address,
const AArch64_reloc_property* reloc_property)
{
// Calculate relocation.
Address x = psymval->value(object, addend) - address;
return This::template reloc_common<valsize>(view, x, reloc_property);
}
// Calculate (S + A) - address, update adr instruction.
static inline typename This::Status
adr(unsigned char* view,
const Sized_relobj_file<size, big_endian>* object,
const Symbol_value<size>* psymval,
Address addend,
Address address,
const AArch64_reloc_property* /* reloc_property */)
{
AArch64_valtype x = psymval->value(object, addend) - address;
// Pick bits [20:0] of X.
AArch64_valtype immed = x & 0x1fffff;
update_adr(view, immed);
// Check -2^20 <= X < 2^20
return (size == 64 && Bits<21>::has_overflow((x))
? This::STATUS_OVERFLOW
: This::STATUS_OKAY);
}
// Calculate PG(S+A) - PG(address), update adrp instruction.
// R_AARCH64_ADR_PREL_PG_HI21
static inline typename This::Status
adrp(
unsigned char* view,
Address sa,
Address address)
{
AArch64_valtype x = This::Page(sa) - This::Page(address);
// Pick [32:12] of X.
AArch64_valtype immed = (x >> 12) & 0x1fffff;
update_adr(view, immed);
// Check -2^32 <= X < 2^32
return (size == 64 && Bits<33>::has_overflow((x))
? This::STATUS_OVERFLOW
: This::STATUS_OKAY);
}
// Calculate PG(S+A) - PG(address), update adrp instruction.
// R_AARCH64_ADR_PREL_PG_HI21
static inline typename This::Status
adrp(unsigned char* view,
const Sized_relobj_file<size, big_endian>* object,
const Symbol_value<size>* psymval,
Address addend,
Address address,
const AArch64_reloc_property* reloc_property)
{
Address sa = psymval->value(object, addend);
AArch64_valtype x = This::Page(sa) - This::Page(address);
// Pick [32:12] of X.
AArch64_valtype immed = (x >> 12) & 0x1fffff;
update_adr(view, immed);
return (reloc_property->checkup_x_value(x)
? This::STATUS_OKAY
: This::STATUS_OVERFLOW);
}
// Update mov[n/z] instruction. Check overflow if needed.
// If X >=0, set the instruction to movz and its immediate value to the
// selected bits S.
// If X < 0, set the instruction to movn and its immediate value to
// NOT (selected bits of).
static inline typename This::Status
movnz(unsigned char* view,
AArch64_valtype x,
const AArch64_reloc_property* reloc_property)
{
// Select bits from X.
Address immed;
bool is_movz;
typedef typename elfcpp::Elf_types<size>::Elf_Swxword SignedW;
if (static_cast<SignedW>(x) >= 0)
{
immed = reloc_property->select_x_value(x);
is_movz = true;
}
else
{
immed = reloc_property->select_x_value(~x);;
is_movz = false;
}
// Update movnz instruction.
update_movnz(view, immed, is_movz);
// Do check overflow or alignment if needed.
return (reloc_property->checkup_x_value(x)
? This::STATUS_OKAY
: This::STATUS_OVERFLOW);
}
static inline bool
maybe_apply_stub(unsigned int,
const The_relocate_info*,
const The_rela&,
unsigned char*,
Address,
const Sized_symbol<size>*,
const Symbol_value<size>*,
const Sized_relobj_file<size, big_endian>*,
section_size_type);
}; // End of AArch64_relocate_functions
// For a certain relocation type (usually jump/branch), test to see if the
// destination needs a stub to fulfil. If so, re-route the destination of the
// original instruction to the stub, note, at this time, the stub has already
// been generated.
template<int size, bool big_endian>
bool
AArch64_relocate_functions<size, big_endian>::
maybe_apply_stub(unsigned int r_type,
const The_relocate_info* relinfo,
const The_rela& rela,
unsigned char* view,
Address address,
const Sized_symbol<size>* gsym,
const Symbol_value<size>* psymval,
const Sized_relobj_file<size, big_endian>* object,
section_size_type current_group_size)
{
if (parameters->options().relocatable())
return false;
typename elfcpp::Elf_types<size>::Elf_Swxword addend = rela.get_r_addend();
Address branch_target = psymval->value(object, 0) + addend;
int stub_type =
The_reloc_stub::stub_type_for_reloc(r_type, address, branch_target);
if (stub_type == ST_NONE)
return false;
const The_aarch64_relobj* aarch64_relobj =
static_cast<const The_aarch64_relobj*>(object);
The_stub_table* stub_table = aarch64_relobj->stub_table(relinfo->data_shndx);
gold_assert(stub_table != NULL);
unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
typename The_reloc_stub::Key stub_key(stub_type, gsym, object, r_sym, addend);
The_reloc_stub* stub = stub_table->find_reloc_stub(stub_key);
gold_assert(stub != NULL);
Address new_branch_target = stub_table->address() + stub->offset();
typename elfcpp::Swap<size, big_endian>::Valtype branch_offset =
new_branch_target - address;
const AArch64_reloc_property* arp =
aarch64_reloc_property_table->get_reloc_property(r_type);
gold_assert(arp != NULL);
typename This::Status status = This::template
rela_general<32>(view, branch_offset, 0, arp);
if (status != This::STATUS_OKAY)
gold_error(_("Stub is too far away, try a smaller value "
"for '--stub-group-size'. The current value is 0x%lx."),
static_cast<unsigned long>(current_group_size));
return true;
}
// Group input sections for stub generation.
//
// We group input sections in an output section so that the total size,
// including any padding space due to alignment is smaller than GROUP_SIZE
// unless the only input section in group is bigger than GROUP_SIZE already.
// Then an ARM stub table is created to follow the last input section
// in group. For each group an ARM stub table is created an is placed
// after the last group. If STUB_ALWAYS_AFTER_BRANCH is false, we further
// extend the group after the stub table.
template<int size, bool big_endian>
void
Target_aarch64<size, big_endian>::group_sections(
Layout* layout,
section_size_type group_size,
bool stubs_always_after_branch,
const Task* task)
{
// Group input sections and insert stub table
Layout::Section_list section_list;
layout->get_executable_sections(&section_list);
for (Layout::Section_list::const_iterator p = section_list.begin();
p != section_list.end();
++p)
{
AArch64_output_section<size, big_endian>* output_section =
static_cast<AArch64_output_section<size, big_endian>*>(*p);
output_section->group_sections(group_size, stubs_always_after_branch,
this, task);
}
}
// Find the AArch64_input_section object corresponding to the SHNDX-th input
// section of RELOBJ.
template<int size, bool big_endian>
AArch64_input_section<size, big_endian>*
Target_aarch64<size, big_endian>::find_aarch64_input_section(
Relobj* relobj, unsigned int shndx) const
{
Section_id sid(relobj, shndx);
typename AArch64_input_section_map::const_iterator p =
this->aarch64_input_section_map_.find(sid);
return (p != this->aarch64_input_section_map_.end()) ? p->second : NULL;
}
// Make a new AArch64_input_section object.
template<int size, bool big_endian>
AArch64_input_section<size, big_endian>*
Target_aarch64<size, big_endian>::new_aarch64_input_section(
Relobj* relobj, unsigned int shndx)
{
Section_id sid(relobj, shndx);
AArch64_input_section<size, big_endian>* input_section =
new AArch64_input_section<size, big_endian>(relobj, shndx);
input_section->init();
// Register new AArch64_input_section in map for look-up.
std::pair<typename AArch64_input_section_map::iterator,bool> ins =
this->aarch64_input_section_map_.insert(
std::make_pair(sid, input_section));
// Make sure that it we have not created another AArch64_input_section
// for this input section already.
gold_assert(ins.second);
return input_section;
}
// Relaxation hook. This is where we do stub generation.
template<int size, bool big_endian>
bool
Target_aarch64<size, big_endian>::do_relax(
int pass,
const Input_objects* input_objects,
Symbol_table* symtab,
Layout* layout ,
const Task* task)
{
gold_assert(!parameters->options().relocatable());
if (pass == 1)
{
// We don't handle negative stub_group_size right now.
this->stub_group_size_ = abs(parameters->options().stub_group_size());
if (this->stub_group_size_ == 1)
{
// Leave room for 4096 4-byte stub entries. If we exceed that, then we
// will fail to link. The user will have to relink with an explicit
// group size option.
this->stub_group_size_ = The_reloc_stub::MAX_BRANCH_OFFSET -
4096 * 4;
}
group_sections(layout, this->stub_group_size_, true, task);
}
else
{
// If this is not the first pass, addresses and file offsets have
// been reset at this point, set them here.
for (Stub_table_iterator sp = this->stub_tables_.begin();
sp != this->stub_tables_.end(); ++sp)
{
The_stub_table* stt = *sp;
The_aarch64_input_section* owner = stt->owner();
off_t off = align_address(owner->original_size(),
stt->addralign());
stt->set_address_and_file_offset(owner->address() + off,
owner->offset() + off);
}
}
// Scan relocs for relocation stubs
for (Input_objects::Relobj_iterator op = input_objects->relobj_begin();
op != input_objects->relobj_end();
++op)
{
The_aarch64_relobj* aarch64_relobj =
static_cast<The_aarch64_relobj*>(*op);
// Lock the object so we can read from it. This is only called
// single-threaded from Layout::finalize, so it is OK to lock.
Task_lock_obj<Object> tl(task, aarch64_relobj);
aarch64_relobj->scan_sections_for_stubs(this, symtab, layout);
}
bool any_stub_table_changed = false;
for (Stub_table_iterator siter = this->stub_tables_.begin();
siter != this->stub_tables_.end() && !any_stub_table_changed; ++siter)
{
The_stub_table* stub_table = *siter;
if (stub_table->update_data_size_changed_p())
{
The_aarch64_input_section* owner = stub_table->owner();
uint64_t address = owner->address();
off_t offset = owner->offset();
owner->reset_address_and_file_offset();
owner->set_address_and_file_offset(address, offset);
any_stub_table_changed = true;
}
}
// Do not continue relaxation.
bool continue_relaxation = any_stub_table_changed;
if (!continue_relaxation)
for (Stub_table_iterator sp = this->stub_tables_.begin();
(sp != this->stub_tables_.end());
++sp)
(*sp)->finalize_stubs();
return continue_relaxation;
}
// Make a new Stub_table.
template<int size, bool big_endian>
Stub_table<size, big_endian>*
Target_aarch64<size, big_endian>::new_stub_table(
AArch64_input_section<size, big_endian>* owner)
{
Stub_table<size, big_endian>* stub_table =
new Stub_table<size, big_endian>(owner);
stub_table->set_address(align_address(
owner->address() + owner->data_size(), 8));
stub_table->set_file_offset(owner->offset() + owner->data_size());
stub_table->finalize_data_size();
this->stub_tables_.push_back(stub_table);
return stub_table;
}
template<int size, bool big_endian>
uint64_t
Target_aarch64<size, big_endian>::do_reloc_addend(
void* arg, unsigned int r_type, uint64_t) const
{
gold_assert(r_type == elfcpp::R_AARCH64_TLSDESC);
uintptr_t intarg = reinterpret_cast<uintptr_t>(arg);
gold_assert(intarg < this->tlsdesc_reloc_info_.size());
const Tlsdesc_info& ti(this->tlsdesc_reloc_info_[intarg]);
const Symbol_value<size>* psymval = ti.object->local_symbol(ti.r_sym);
gold_assert(psymval->is_tls_symbol());
// The value of a TLS symbol is the offset in the TLS segment.
return psymval->value(ti.object, 0);
}
// Return the number of entries in the PLT.
template<int size, bool big_endian>
unsigned int
Target_aarch64<size, big_endian>::plt_entry_count() const
{
if (this->plt_ == NULL)
return 0;
return this->plt_->entry_count();
}
// Return the offset of the first non-reserved PLT entry.
template<int size, bool big_endian>
unsigned int
Target_aarch64<size, big_endian>::first_plt_entry_offset() const
{
return this->plt_->first_plt_entry_offset();
}
// Return the size of each PLT entry.
template<int size, bool big_endian>
unsigned int
Target_aarch64<size, big_endian>::plt_entry_size() const
{
return this->plt_->get_plt_entry_size();
}
// Define the _TLS_MODULE_BASE_ symbol in the TLS segment.
template<int size, bool big_endian>
void
Target_aarch64<size, big_endian>::define_tls_base_symbol(
Symbol_table* symtab, Layout* layout)
{
if (this->tls_base_symbol_defined_)
return;
Output_segment* tls_segment = layout->tls_segment();
if (tls_segment != NULL)
{
// _TLS_MODULE_BASE_ always points to the beginning of tls segment.
symtab->define_in_output_segment("_TLS_MODULE_BASE_", NULL,
Symbol_table::PREDEFINED,
tls_segment, 0, 0,
elfcpp::STT_TLS,
elfcpp::STB_LOCAL,
elfcpp::STV_HIDDEN, 0,
Symbol::SEGMENT_START,
true);
}
this->tls_base_symbol_defined_ = true;
}
// Create the reserved PLT and GOT entries for the TLS descriptor resolver.
template<int size, bool big_endian>
void
Target_aarch64<size, big_endian>::reserve_tlsdesc_entries(
Symbol_table* symtab, Layout* layout)
{
if (this->plt_ == NULL)
this->make_plt_section(symtab, layout);
if (!this->plt_->has_tlsdesc_entry())
{
// Allocate the TLSDESC_GOT entry.
Output_data_got_aarch64<size, big_endian>* got =
this->got_section(symtab, layout);
unsigned int got_offset = got->add_constant(0);
// Allocate the TLSDESC_PLT entry.
this->plt_->reserve_tlsdesc_entry(got_offset);
}
}
// Create a GOT entry for the TLS module index.
template<int size, bool big_endian>
unsigned int
Target_aarch64<size, big_endian>::got_mod_index_entry(
Symbol_table* symtab, Layout* layout,
Sized_relobj_file<size, big_endian>* object)
{
if (this->got_mod_index_offset_ == -1U)
{
gold_assert(symtab != NULL && layout != NULL && object != NULL);
Reloc_section* rela_dyn = this->rela_dyn_section(layout);
Output_data_got_aarch64<size, big_endian>* got =
this->got_section(symtab, layout);
unsigned int got_offset = got->add_constant(0);
rela_dyn->add_local(object, 0, elfcpp::R_AARCH64_TLS_DTPMOD64, got,
got_offset, 0);
got->add_constant(0);
this->got_mod_index_offset_ = got_offset;
}
return this->got_mod_index_offset_;
}
// Optimize the TLS relocation type based on what we know about the
// symbol. IS_FINAL is true if the final address of this symbol is
// known at link time.
template<int size, bool big_endian>
tls::Tls_optimization
Target_aarch64<size, big_endian>::optimize_tls_reloc(bool is_final,
int r_type)
{
// If we are generating a shared library, then we can't do anything
// in the linker
if (parameters->options().shared())
return tls::TLSOPT_NONE;
switch (r_type)
{
case elfcpp::R_AARCH64_TLSGD_ADR_PAGE21:
case elfcpp::R_AARCH64_TLSGD_ADD_LO12_NC:
case elfcpp::R_AARCH64_TLSDESC_LD_PREL19:
case elfcpp::R_AARCH64_TLSDESC_ADR_PREL21:
case elfcpp::R_AARCH64_TLSDESC_ADR_PAGE21:
case elfcpp::R_AARCH64_TLSDESC_LD64_LO12:
case elfcpp::R_AARCH64_TLSDESC_ADD_LO12:
case elfcpp::R_AARCH64_TLSDESC_OFF_G1:
case elfcpp::R_AARCH64_TLSDESC_OFF_G0_NC:
case elfcpp::R_AARCH64_TLSDESC_LDR:
case elfcpp::R_AARCH64_TLSDESC_ADD:
case elfcpp::R_AARCH64_TLSDESC_CALL:
// These are General-Dynamic which permits fully general TLS
// access. Since we know that we are generating an executable,
// we can convert this to Initial-Exec. If we also know that
// this is a local symbol, we can further switch to Local-Exec.
if (is_final)
return tls::TLSOPT_TO_LE;
return tls::TLSOPT_TO_IE;
case elfcpp::R_AARCH64_TLSLD_ADR_PAGE21:
case elfcpp::R_AARCH64_TLSLD_ADD_LO12_NC:
case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G1:
case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G0_NC:
case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_HI12:
case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_LO12_NC:
// These are Local-Dynamic, which refer to local symbols in the
// dynamic TLS block. Since we know that we generating an
// executable, we can switch to Local-Exec.
return tls::TLSOPT_TO_LE;
case elfcpp::R_AARCH64_TLSIE_MOVW_GOTTPREL_G1:
case elfcpp::R_AARCH64_TLSIE_MOVW_GOTTPREL_G0_NC:
case elfcpp::R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21:
case elfcpp::R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC:
case elfcpp::R_AARCH64_TLSIE_LD_GOTTPREL_PREL19:
// These are Initial-Exec relocs which get the thread offset
// from the GOT. If we know that we are linking against the
// local symbol, we can switch to Local-Exec, which links the
// thread offset into the instruction.
if (is_final)
return tls::TLSOPT_TO_LE;
return tls::TLSOPT_NONE;
case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G2:
case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G1:
case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G1_NC:
case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G0:
case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G0_NC:
case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_HI12:
case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12:
case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12_NC:
// When we already have Local-Exec, there is nothing further we
// can do.
return tls::TLSOPT_NONE;
default:
gold_unreachable();
}
}
// Returns true if this relocation type could be that of a function pointer.
template<int size, bool big_endian>
inline bool
Target_aarch64<size, big_endian>::Scan::possible_function_pointer_reloc(
unsigned int r_type)
{
switch (r_type)
{
case elfcpp::R_AARCH64_ADR_PREL_PG_HI21:
case elfcpp::R_AARCH64_ADR_PREL_PG_HI21_NC:
case elfcpp::R_AARCH64_ADD_ABS_LO12_NC:
case elfcpp::R_AARCH64_ADR_GOT_PAGE:
case elfcpp::R_AARCH64_LD64_GOT_LO12_NC:
{
return true;
}
}
return false;
}
// For safe ICF, scan a relocation for a local symbol to check if it
// corresponds to a function pointer being taken. In that case mark
// the function whose pointer was taken as not foldable.
template<int size, bool big_endian>
inline bool
Target_aarch64<size, big_endian>::Scan::local_reloc_may_be_function_pointer(
Symbol_table* ,
Layout* ,
Target_aarch64<size, big_endian>* ,
Sized_relobj_file<size, big_endian>* ,
unsigned int ,
Output_section* ,
const elfcpp::Rela<size, big_endian>& ,
unsigned int r_type,
const elfcpp::Sym<size, big_endian>&)
{
// When building a shared library, do not fold any local symbols.
return (parameters->options().shared()
|| possible_function_pointer_reloc(r_type));
}
// For safe ICF, scan a relocation for a global symbol to check if it
// corresponds to a function pointer being taken. In that case mark
// the function whose pointer was taken as not foldable.
template<int size, bool big_endian>
inline bool
Target_aarch64<size, big_endian>::Scan::global_reloc_may_be_function_pointer(
Symbol_table* ,
Layout* ,
Target_aarch64<size, big_endian>* ,
Sized_relobj_file<size, big_endian>* ,
unsigned int ,
Output_section* ,
const elfcpp::Rela<size, big_endian>& ,
unsigned int r_type,
Symbol* gsym)
{
// When building a shared library, do not fold symbols whose visibility
// is hidden, internal or protected.
return ((parameters->options().shared()
&& (gsym->visibility() == elfcpp::STV_INTERNAL
|| gsym->visibility() == elfcpp::STV_PROTECTED
|| gsym->visibility() == elfcpp::STV_HIDDEN))
|| possible_function_pointer_reloc(r_type));
}
// Report an unsupported relocation against a local symbol.
template<int size, bool big_endian>
void
Target_aarch64<size, big_endian>::Scan::unsupported_reloc_local(
Sized_relobj_file<size, big_endian>* object,
unsigned int r_type)
{
gold_error(_("%s: unsupported reloc %u against local symbol"),
object->name().c_str(), r_type);
}
// We are about to emit a dynamic relocation of type R_TYPE. If the
// dynamic linker does not support it, issue an error.
template<int size, bool big_endian>
void
Target_aarch64<size, big_endian>::Scan::check_non_pic(Relobj* object,
unsigned int r_type)
{
gold_assert(r_type != elfcpp::R_AARCH64_NONE);
switch (r_type)
{
// These are the relocation types supported by glibc for AARCH64.
case elfcpp::R_AARCH64_NONE:
case elfcpp::R_AARCH64_COPY:
case elfcpp::R_AARCH64_GLOB_DAT:
case elfcpp::R_AARCH64_JUMP_SLOT:
case elfcpp::R_AARCH64_RELATIVE:
case elfcpp::R_AARCH64_TLS_DTPREL64:
case elfcpp::R_AARCH64_TLS_DTPMOD64:
case elfcpp::R_AARCH64_TLS_TPREL64:
case elfcpp::R_AARCH64_TLSDESC:
case elfcpp::R_AARCH64_IRELATIVE:
case elfcpp::R_AARCH64_ABS32:
case elfcpp::R_AARCH64_ABS64:
return;
default:
break;
}
// This prevents us from issuing more than one error per reloc
// section. But we can still wind up issuing more than one
// error per object file.
if (this->issued_non_pic_error_)
return;
gold_assert(parameters->options().output_is_position_independent());
object->error(_("requires unsupported dynamic reloc; "
"recompile with -fPIC"));
this->issued_non_pic_error_ = true;
return;
}
// Return whether we need to make a PLT entry for a relocation of the
// given type against a STT_GNU_IFUNC symbol.
template<int size, bool big_endian>
bool
Target_aarch64<size, big_endian>::Scan::reloc_needs_plt_for_ifunc(
Sized_relobj_file<size, big_endian>* object,
unsigned int r_type)
{
const AArch64_reloc_property* arp =
aarch64_reloc_property_table->get_reloc_property(r_type);
gold_assert(arp != NULL);
int flags = arp->reference_flags();
if (flags & Symbol::TLS_REF)
{
gold_error(_("%s: unsupported TLS reloc %s for IFUNC symbol"),
object->name().c_str(), arp->name().c_str());
return false;
}
return flags != 0;
}
// Scan a relocation for a local symbol.
template<int size, bool big_endian>
inline void
Target_aarch64<size, big_endian>::Scan::local(
Symbol_table* symtab,
Layout* layout,
Target_aarch64<size, big_endian>* target,
Sized_relobj_file<size, big_endian>* object,
unsigned int data_shndx,
Output_section* output_section,
const elfcpp::Rela<size, big_endian>& rela,
unsigned int r_type,
const elfcpp::Sym<size, big_endian>& lsym,
bool is_discarded)
{
if (is_discarded)
return;
typedef Output_data_reloc<elfcpp::SHT_RELA, true, size, big_endian>
Reloc_section;
Output_data_got_aarch64<size, big_endian>* got =
target->got_section(symtab, layout);
unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
// A local STT_GNU_IFUNC symbol may require a PLT entry.
bool is_ifunc = lsym.get_st_type() == elfcpp::STT_GNU_IFUNC;
if (is_ifunc && this->reloc_needs_plt_for_ifunc(object, r_type))
target->make_local_ifunc_plt_entry(symtab, layout, object, r_sym);
switch (r_type)
{
case elfcpp::R_AARCH64_ABS32:
case elfcpp::R_AARCH64_ABS16:
if (parameters->options().output_is_position_independent())
{
gold_error(_("%s: unsupported reloc %u in pos independent link."),
object->name().c_str(), r_type);
}
break;
case elfcpp::R_AARCH64_ABS64:
// If building a shared library or pie, we need to mark this as a dynmic
// reloction, so that the dynamic loader can relocate it.
if (parameters->options().output_is_position_independent())
{
Reloc_section* rela_dyn = target->rela_dyn_section(layout);
rela_dyn->add_local_relative(object, r_sym,
elfcpp::R_AARCH64_RELATIVE,
output_section,
data_shndx,
rela.get_r_offset(),
rela.get_r_addend(),
is_ifunc);
}
break;
case elfcpp::R_AARCH64_PREL64:
case elfcpp::R_AARCH64_PREL32:
case elfcpp::R_AARCH64_PREL16:
break;
case elfcpp::R_AARCH64_ADR_GOT_PAGE:
case elfcpp::R_AARCH64_LD64_GOT_LO12_NC:
// This pair of relocations is used to access a specific GOT entry.
{
bool is_new = false;
// This symbol requires a GOT entry.
if (is_ifunc)
is_new = got->add_local_plt(object, r_sym, GOT_TYPE_STANDARD);
else
is_new = got->add_local(object, r_sym, GOT_TYPE_STANDARD);
if (is_new && parameters->options().output_is_position_independent())
target->rela_dyn_section(layout)->
add_local_relative(object,
r_sym,
elfcpp::R_AARCH64_RELATIVE,
got,
object->local_got_offset(r_sym,
GOT_TYPE_STANDARD),
0,
false);
}
break;
case elfcpp::R_AARCH64_LD_PREL_LO19: // 273
case elfcpp::R_AARCH64_ADR_PREL_LO21: // 274
case elfcpp::R_AARCH64_ADR_PREL_PG_HI21: // 275
case elfcpp::R_AARCH64_ADR_PREL_PG_HI21_NC: // 276
case elfcpp::R_AARCH64_ADD_ABS_LO12_NC: // 277
case elfcpp::R_AARCH64_LDST8_ABS_LO12_NC: // 278
case elfcpp::R_AARCH64_LDST16_ABS_LO12_NC: // 284
case elfcpp::R_AARCH64_LDST32_ABS_LO12_NC: // 285
case elfcpp::R_AARCH64_LDST64_ABS_LO12_NC: // 286
case elfcpp::R_AARCH64_LDST128_ABS_LO12_NC: // 299
break;
// Control flow, pc-relative. We don't need to do anything for a relative
// addressing relocation against a local symbol if it does not reference
// the GOT.
case elfcpp::R_AARCH64_TSTBR14:
case elfcpp::R_AARCH64_CONDBR19:
case elfcpp::R_AARCH64_JUMP26:
case elfcpp::R_AARCH64_CALL26:
break;
case elfcpp::R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21:
case elfcpp::R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC:
{
tls::Tls_optimization tlsopt = Target_aarch64<size, big_endian>::
optimize_tls_reloc(!parameters->options().shared(), r_type);
if (tlsopt == tls::TLSOPT_TO_LE)
break;
layout->set_has_static_tls();
// Create a GOT entry for the tp-relative offset.
if (!parameters->doing_static_link())
{
got->add_local_with_rel(object, r_sym, GOT_TYPE_TLS_OFFSET,
target->rela_dyn_section(layout),
elfcpp::R_AARCH64_TLS_TPREL64);
}
else if (!object->local_has_got_offset(r_sym,
GOT_TYPE_TLS_OFFSET))
{
got->add_local(object, r_sym, GOT_TYPE_TLS_OFFSET);
unsigned int got_offset =
object->local_got_offset(r_sym, GOT_TYPE_TLS_OFFSET);
const elfcpp::Elf_Xword addend = rela.get_r_addend();
gold_assert(addend == 0);
got->add_static_reloc(got_offset, elfcpp::R_AARCH64_TLS_TPREL64,
object, r_sym);
}
}
break;
case elfcpp::R_AARCH64_TLSGD_ADR_PAGE21:
case elfcpp::R_AARCH64_TLSGD_ADD_LO12_NC:
{
tls::Tls_optimization tlsopt = Target_aarch64<size, big_endian>::
optimize_tls_reloc(!parameters->options().shared(), r_type);
if (tlsopt == tls::TLSOPT_TO_LE)
{
layout->set_has_static_tls();
break;
}
gold_assert(tlsopt == tls::TLSOPT_NONE);
got->add_local_pair_with_rel(object,r_sym, data_shndx,
GOT_TYPE_TLS_PAIR,
target->rela_dyn_section(layout),
elfcpp::R_AARCH64_TLS_DTPMOD64);
}
break;
case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G2:
case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G1:
case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G1_NC:
case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G0:
case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G0_NC:
case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_HI12:
case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12:
case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12_NC:
{
layout->set_has_static_tls();
bool output_is_shared = parameters->options().shared();
if (output_is_shared)
gold_error(_("%s: unsupported TLSLE reloc %u in shared code."),
object->name().c_str(), r_type);
}
break;
case elfcpp::R_AARCH64_TLSLD_ADR_PAGE21:
case elfcpp::R_AARCH64_TLSLD_ADD_LO12_NC:
{
tls::Tls_optimization tlsopt = Target_aarch64<size, big_endian>::
optimize_tls_reloc(!parameters->options().shared(), r_type);
if (tlsopt == tls::TLSOPT_NONE)
{
// Create a GOT entry for the module index.
target->got_mod_index_entry(symtab, layout, object);
}
else if (tlsopt != tls::TLSOPT_TO_LE)
unsupported_reloc_local(object, r_type);
}
break;
case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G1:
case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G0_NC:
case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_HI12:
case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_LO12_NC:
break;
case elfcpp::R_AARCH64_TLSDESC_ADR_PAGE21:
case elfcpp::R_AARCH64_TLSDESC_LD64_LO12:
case elfcpp::R_AARCH64_TLSDESC_ADD_LO12:
{
tls::Tls_optimization tlsopt = Target_aarch64<size, big_endian>::
optimize_tls_reloc(!parameters->options().shared(), r_type);
target->define_tls_base_symbol(symtab, layout);
if (tlsopt == tls::TLSOPT_NONE)
{
// Create reserved PLT and GOT entries for the resolver.
target->reserve_tlsdesc_entries(symtab, layout);
// Generate a double GOT entry with an R_AARCH64_TLSDESC reloc.
// The R_AARCH64_TLSDESC reloc is resolved lazily, so the GOT
// entry needs to be in an area in .got.plt, not .got. Call
// got_section to make sure the section has been created.
target->got_section(symtab, layout);
Output_data_got<size, big_endian>* got =
target->got_tlsdesc_section();
unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
if (!object->local_has_got_offset(r_sym, GOT_TYPE_TLS_DESC))
{
unsigned int got_offset = got->add_constant(0);
got->add_constant(0);
object->set_local_got_offset(r_sym, GOT_TYPE_TLS_DESC,
got_offset);
Reloc_section* rt = target->rela_tlsdesc_section(layout);
// We store the arguments we need in a vector, and use
// the index into the vector as the parameter to pass
// to the target specific routines.
uintptr_t intarg = target->add_tlsdesc_info(object, r_sym);
void* arg = reinterpret_cast<void*>(intarg);
rt->add_target_specific(elfcpp::R_AARCH64_TLSDESC, arg,
got, got_offset, 0);
}
}
else if (tlsopt != tls::TLSOPT_TO_LE)
unsupported_reloc_local(object, r_type);
}
break;
case elfcpp::R_AARCH64_TLSDESC_CALL:
break;
default:
unsupported_reloc_local(object, r_type);
}
}
// Report an unsupported relocation against a global symbol.
template<int size, bool big_endian>
void
Target_aarch64<size, big_endian>::Scan::unsupported_reloc_global(
Sized_relobj_file<size, big_endian>* object,
unsigned int r_type,
Symbol* gsym)
{
gold_error(_("%s: unsupported reloc %u against global symbol %s"),
object->name().c_str(), r_type, gsym->demangled_name().c_str());
}
template<int size, bool big_endian>
inline void
Target_aarch64<size, big_endian>::Scan::global(
Symbol_table* symtab,
Layout* layout,
Target_aarch64<size, big_endian>* target,
Sized_relobj_file<size, big_endian> * object,
unsigned int data_shndx,
Output_section* output_section,
const elfcpp::Rela<size, big_endian>& rela,
unsigned int r_type,
Symbol* gsym)
{
// A STT_GNU_IFUNC symbol may require a PLT entry.
if (gsym->type() == elfcpp::STT_GNU_IFUNC
&& this->reloc_needs_plt_for_ifunc(object, r_type))
target->make_plt_entry(symtab, layout, gsym);
typedef Output_data_reloc<elfcpp::SHT_RELA, true, size, big_endian>
Reloc_section;
const AArch64_reloc_property* arp =
aarch64_reloc_property_table->get_reloc_property(r_type);
gold_assert(arp != NULL);
switch (r_type)
{
case elfcpp::R_AARCH64_ABS16:
case elfcpp::R_AARCH64_ABS32:
case elfcpp::R_AARCH64_ABS64:
{
// Make a PLT entry if necessary.
if (gsym->needs_plt_entry())
{
target->make_plt_entry(symtab, layout, gsym);
// Since this is not a PC-relative relocation, we may be
// taking the address of a function. In that case we need to
// set the entry in the dynamic symbol table to the address of
// the PLT entry.
if (gsym->is_from_dynobj() && !parameters->options().shared())
gsym->set_needs_dynsym_value();
}
// Make a dynamic relocation if necessary.
if (gsym->needs_dynamic_reloc(arp->reference_flags()))
{
if (!parameters->options().output_is_position_independent()
&& gsym->may_need_copy_reloc())
{
target->copy_reloc(symtab, layout, object,
data_shndx, output_section, gsym, rela);
}
else if (r_type == elfcpp::R_AARCH64_ABS64
&& gsym->type() == elfcpp::STT_GNU_IFUNC
&& gsym->can_use_relative_reloc(false)
&& !gsym->is_from_dynobj()
&& !gsym->is_undefined()
&& !gsym->is_preemptible())
{
// Use an IRELATIVE reloc for a locally defined STT_GNU_IFUNC
// symbol. This makes a function address in a PIE executable
// match the address in a shared library that it links against.
Reloc_section* rela_dyn =
target->rela_irelative_section(layout);
unsigned int r_type = elfcpp::R_AARCH64_IRELATIVE;
rela_dyn->add_symbolless_global_addend(gsym, r_type,
output_section, object,
data_shndx,
rela.get_r_offset(),
rela.get_r_addend());
}
else if (r_type == elfcpp::R_AARCH64_ABS64
&& gsym->can_use_relative_reloc(false))
{
Reloc_section* rela_dyn = target->rela_dyn_section(layout);
rela_dyn->add_global_relative(gsym,
elfcpp::R_AARCH64_RELATIVE,
output_section,
object,
data_shndx,
rela.get_r_offset(),
rela.get_r_addend(),
false);
}
else
{
check_non_pic(object, r_type);
Output_data_reloc<elfcpp::SHT_RELA, true, size, big_endian>*
rela_dyn = target->rela_dyn_section(layout);
rela_dyn->add_global(
gsym, r_type, output_section, object,
data_shndx, rela.get_r_offset(),rela.get_r_addend());
}
}
}
break;
case elfcpp::R_AARCH64_PREL16:
case elfcpp::R_AARCH64_PREL32:
case elfcpp::R_AARCH64_PREL64:
// This is used to fill the GOT absolute address.
if (gsym->needs_plt_entry())
{
target->make_plt_entry(symtab, layout, gsym);
}
break;
case elfcpp::R_AARCH64_LD_PREL_LO19: // 273
case elfcpp::R_AARCH64_ADR_PREL_LO21: // 274
case elfcpp::R_AARCH64_ADR_PREL_PG_HI21: // 275
case elfcpp::R_AARCH64_ADR_PREL_PG_HI21_NC: // 276
case elfcpp::R_AARCH64_ADD_ABS_LO12_NC: // 277
case elfcpp::R_AARCH64_LDST8_ABS_LO12_NC: // 278
case elfcpp::R_AARCH64_LDST16_ABS_LO12_NC: // 284
case elfcpp::R_AARCH64_LDST32_ABS_LO12_NC: // 285
case elfcpp::R_AARCH64_LDST64_ABS_LO12_NC: // 286
case elfcpp::R_AARCH64_LDST128_ABS_LO12_NC: // 299
{
if (gsym->needs_plt_entry())
target->make_plt_entry(symtab, layout, gsym);
// Make a dynamic relocation if necessary.
if (gsym->needs_dynamic_reloc(arp->reference_flags()))
{
if (parameters->options().output_is_executable()
&& gsym->may_need_copy_reloc())
{
target->copy_reloc(symtab, layout, object,
data_shndx, output_section, gsym, rela);
}
}
break;
}
case elfcpp::R_AARCH64_ADR_GOT_PAGE:
case elfcpp::R_AARCH64_LD64_GOT_LO12_NC:
{
// This pair of relocations is used to access a specific GOT entry.
// Note a GOT entry is an *address* to a symbol.
// The symbol requires a GOT entry
Output_data_got_aarch64<size, big_endian>* got =
target->got_section(symtab, layout);
if (gsym->final_value_is_known())
{
// For a STT_GNU_IFUNC symbol we want the PLT address.
if (gsym->type() == elfcpp::STT_GNU_IFUNC)
got->add_global_plt(gsym, GOT_TYPE_STANDARD);
else
got->add_global(gsym, GOT_TYPE_STANDARD);
}
else
{
// If this symbol is not fully resolved, we need to add a dynamic
// relocation for it.
Reloc_section* rela_dyn = target->rela_dyn_section(layout);
// Use a GLOB_DAT rather than a RELATIVE reloc if:
//
// 1) The symbol may be defined in some other module.
// 2) We are building a shared library and this is a protected
// symbol; using GLOB_DAT means that the dynamic linker can use
// the address of the PLT in the main executable when appropriate
// so that function address comparisons work.
// 3) This is a STT_GNU_IFUNC symbol in position dependent code,
// again so that function address comparisons work.
if (gsym->is_from_dynobj()
|| gsym->is_undefined()
|| gsym->is_preemptible()
|| (gsym->visibility() == elfcpp::STV_PROTECTED
&& parameters->options().shared())
|| (gsym->type() == elfcpp::STT_GNU_IFUNC
&& parameters->options().output_is_position_independent()))
got->add_global_with_rel(gsym, GOT_TYPE_STANDARD,
rela_dyn, elfcpp::R_AARCH64_GLOB_DAT);
else
{
// For a STT_GNU_IFUNC symbol we want to write the PLT
// offset into the GOT, so that function pointer
// comparisons work correctly.
bool is_new;
if (gsym->type() != elfcpp::STT_GNU_IFUNC)
is_new = got->add_global(gsym, GOT_TYPE_STANDARD);
else
{
is_new = got->add_global_plt(gsym, GOT_TYPE_STANDARD);
// Tell the dynamic linker to use the PLT address
// when resolving relocations.
if (gsym->is_from_dynobj()
&& !parameters->options().shared())
gsym->set_needs_dynsym_value();
}
if (is_new)
{
rela_dyn->add_global_relative(
gsym, elfcpp::R_AARCH64_RELATIVE,
got,
gsym->got_offset(GOT_TYPE_STANDARD),
0,
false);
}
}
}
break;
}
case elfcpp::R_AARCH64_TSTBR14:
case elfcpp::R_AARCH64_CONDBR19:
case elfcpp::R_AARCH64_JUMP26:
case elfcpp::R_AARCH64_CALL26:
{
if (gsym->final_value_is_known())
break;
if (gsym->is_defined() &&
!gsym->is_from_dynobj() &&
!gsym->is_preemptible())
break;
// Make plt entry for function call.
target->make_plt_entry(symtab, layout, gsym);
break;
}
case elfcpp::R_AARCH64_TLSGD_ADR_PAGE21:
case elfcpp::R_AARCH64_TLSGD_ADD_LO12_NC: // General dynamic
{
tls::Tls_optimization tlsopt = Target_aarch64<size, big_endian>::
optimize_tls_reloc(gsym->final_value_is_known(), r_type);
if (tlsopt == tls::TLSOPT_TO_LE)
{
layout->set_has_static_tls();
break;
}
gold_assert(tlsopt == tls::TLSOPT_NONE);
// General dynamic.
Output_data_got_aarch64<size, big_endian>* got =
target->got_section(symtab, layout);
// Create 2 consecutive entries for module index and offset.
got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_PAIR,
target->rela_dyn_section(layout),
elfcpp::R_AARCH64_TLS_DTPMOD64,
elfcpp::R_AARCH64_TLS_DTPREL64);
}
break;
case elfcpp::R_AARCH64_TLSLD_ADR_PAGE21:
case elfcpp::R_AARCH64_TLSLD_ADD_LO12_NC: // Local dynamic
{
tls::Tls_optimization tlsopt = Target_aarch64<size, big_endian>::
optimize_tls_reloc(!parameters->options().shared(), r_type);
if (tlsopt == tls::TLSOPT_NONE)
{
// Create a GOT entry for the module index.
target->got_mod_index_entry(symtab, layout, object);
}
else if (tlsopt != tls::TLSOPT_TO_LE)
unsupported_reloc_local(object, r_type);
}
break;
case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G1:
case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G0_NC:
case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_HI12:
case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_LO12_NC: // Other local dynamic
break;
case elfcpp::R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21:
case elfcpp::R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC: // Initial executable
{
tls::Tls_optimization tlsopt = Target_aarch64<size, big_endian>::
optimize_tls_reloc(gsym->final_value_is_known(), r_type);
if (tlsopt == tls::TLSOPT_TO_LE)
break;
layout->set_has_static_tls();
// Create a GOT entry for the tp-relative offset.
Output_data_got_aarch64<size, big_endian>* got
= target->got_section(symtab, layout);
if (!parameters->doing_static_link())
{
got->add_global_with_rel(
gsym, GOT_TYPE_TLS_OFFSET,
target->rela_dyn_section(layout),
elfcpp::R_AARCH64_TLS_TPREL64);
}
if (!gsym->has_got_offset(GOT_TYPE_TLS_OFFSET))
{
got->add_global(gsym, GOT_TYPE_TLS_OFFSET);
unsigned int got_offset =
gsym->got_offset(GOT_TYPE_TLS_OFFSET);
const elfcpp::Elf_Xword addend = rela.get_r_addend();
gold_assert(addend == 0);
got->add_static_reloc(got_offset,
elfcpp::R_AARCH64_TLS_TPREL64, gsym);
}
}
break;
case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G2:
case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G1:
case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G1_NC:
case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G0:
case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G0_NC:
case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_HI12:
case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12:
case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12_NC: // Local executable
layout->set_has_static_tls();
if (parameters->options().shared())
gold_error(_("%s: unsupported TLSLE reloc type %u in shared objects."),
object->name().c_str(), r_type);
break;
case elfcpp::R_AARCH64_TLSDESC_ADR_PAGE21:
case elfcpp::R_AARCH64_TLSDESC_LD64_LO12:
case elfcpp::R_AARCH64_TLSDESC_ADD_LO12: // TLS descriptor
{
target->define_tls_base_symbol(symtab, layout);
tls::Tls_optimization tlsopt = Target_aarch64<size, big_endian>::
optimize_tls_reloc(gsym->final_value_is_known(), r_type);
if (tlsopt == tls::TLSOPT_NONE)
{
// Create reserved PLT and GOT entries for the resolver.
target->reserve_tlsdesc_entries(symtab, layout);
// Create a double GOT entry with an R_AARCH64_TLSDESC
// relocation. The R_AARCH64_TLSDESC is resolved lazily, so the GOT
// entry needs to be in an area in .got.plt, not .got. Call
// got_section to make sure the section has been created.
target->got_section(symtab, layout);
Output_data_got<size, big_endian>* got =
target->got_tlsdesc_section();
Reloc_section* rt = target->rela_tlsdesc_section(layout);
got->add_global_pair_with_rel(gsym, GOT_TYPE_TLS_DESC, rt,
elfcpp::R_AARCH64_TLSDESC, 0);
}
else if (tlsopt == tls::TLSOPT_TO_IE)
{
// Create a GOT entry for the tp-relative offset.
Output_data_got<size, big_endian>* got
= target->got_section(symtab, layout);
got->add_global_with_rel(gsym, GOT_TYPE_TLS_OFFSET,
target->rela_dyn_section(layout),
elfcpp::R_AARCH64_TLS_TPREL64);
}
else if (tlsopt != tls::TLSOPT_TO_LE)
unsupported_reloc_global(object, r_type, gsym);
}
break;
case elfcpp::R_AARCH64_TLSDESC_CALL:
break;
default:
gold_error(_("%s: unsupported reloc type in global scan"),
aarch64_reloc_property_table->
reloc_name_in_error_message(r_type).c_str());
}
return;
} // End of Scan::global
// Create the PLT section.
template<int size, bool big_endian>
void
Target_aarch64<size, big_endian>::make_plt_section(
Symbol_table* symtab, Layout* layout)
{
if (this->plt_ == NULL)
{
// Create the GOT section first.
this->got_section(symtab, layout);
this->plt_ = this->make_data_plt(layout, this->got_, this->got_plt_,
this->got_irelative_);
layout->add_output_section_data(".plt", elfcpp::SHT_PROGBITS,
(elfcpp::SHF_ALLOC
| elfcpp::SHF_EXECINSTR),
this->plt_, ORDER_PLT, false);
// Make the sh_info field of .rela.plt point to .plt.
Output_section* rela_plt_os = this->plt_->rela_plt()->output_section();
rela_plt_os->set_info_section(this->plt_->output_section());
}
}
// Return the section for TLSDESC relocations.
template<int size, bool big_endian>
typename Target_aarch64<size, big_endian>::Reloc_section*
Target_aarch64<size, big_endian>::rela_tlsdesc_section(Layout* layout) const
{
return this->plt_section()->rela_tlsdesc(layout);
}
// Create a PLT entry for a global symbol.
template<int size, bool big_endian>
void
Target_aarch64<size, big_endian>::make_plt_entry(
Symbol_table* symtab,
Layout* layout,
Symbol* gsym)
{
if (gsym->has_plt_offset())
return;
if (this->plt_ == NULL)
this->make_plt_section(symtab, layout);
this->plt_->add_entry(symtab, layout, gsym);
}
// Make a PLT entry for a local STT_GNU_IFUNC symbol.
template<int size, bool big_endian>
void
Target_aarch64<size, big_endian>::make_local_ifunc_plt_entry(
Symbol_table* symtab, Layout* layout,
Sized_relobj_file<size, big_endian>* relobj,
unsigned int local_sym_index)
{
if (relobj->local_has_plt_offset(local_sym_index))
return;
if (this->plt_ == NULL)
this->make_plt_section(symtab, layout);
unsigned int plt_offset = this->plt_->add_local_ifunc_entry(symtab, layout,
relobj,
local_sym_index);
relobj->set_local_plt_offset(local_sym_index, plt_offset);
}
template<int size, bool big_endian>
void
Target_aarch64<size, big_endian>::gc_process_relocs(
Symbol_table* symtab,
Layout* layout,
Sized_relobj_file<size, big_endian>* object,
unsigned int data_shndx,
unsigned int sh_type,
const unsigned char* prelocs,
size_t reloc_count,
Output_section* output_section,
bool needs_special_offset_handling,
size_t local_symbol_count,
const unsigned char* plocal_symbols)
{
if (sh_type == elfcpp::SHT_REL)
{
return;
}
gold::gc_process_relocs<
size, big_endian,
Target_aarch64<size, big_endian>,
elfcpp::SHT_RELA,
typename Target_aarch64<size, big_endian>::Scan,
typename Target_aarch64<size, big_endian>::Relocatable_size_for_reloc>(
symtab,
layout,
this,
object,
data_shndx,
prelocs,
reloc_count,
output_section,
needs_special_offset_handling,
local_symbol_count,
plocal_symbols);
}
// Scan relocations for a section.
template<int size, bool big_endian>
void
Target_aarch64<size, big_endian>::scan_relocs(
Symbol_table* symtab,
Layout* layout,
Sized_relobj_file<size, big_endian>* object,
unsigned int data_shndx,
unsigned int sh_type,
const unsigned char* prelocs,
size_t reloc_count,
Output_section* output_section,
bool needs_special_offset_handling,
size_t local_symbol_count,
const unsigned char* plocal_symbols)
{
if (sh_type == elfcpp::SHT_REL)
{
gold_error(_("%s: unsupported REL reloc section"),
object->name().c_str());
return;
}
gold::scan_relocs<size, big_endian, Target_aarch64, elfcpp::SHT_RELA, Scan>(
symtab,
layout,
this,
object,
data_shndx,
prelocs,
reloc_count,
output_section,
needs_special_offset_handling,
local_symbol_count,
plocal_symbols);
}
// Return the value to use for a dynamic which requires special
// treatment. This is how we support equality comparisons of function
// pointers across shared library boundaries, as described in the
// processor specific ABI supplement.
template<int size, bool big_endian>
uint64_t
Target_aarch64<size, big_endian>::do_dynsym_value(const Symbol* gsym) const
{
gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset());
return this->plt_address_for_global(gsym);
}
// Finalize the sections.
template<int size, bool big_endian>
void
Target_aarch64<size, big_endian>::do_finalize_sections(
Layout* layout,
const Input_objects*,
Symbol_table* symtab)
{
const Reloc_section* rel_plt = (this->plt_ == NULL
? NULL
: this->plt_->rela_plt());
layout->add_target_dynamic_tags(false, this->got_plt_, rel_plt,
this->rela_dyn_, true, false);
// Emit any relocs we saved in an attempt to avoid generating COPY
// relocs.
if (this->copy_relocs_.any_saved_relocs())
this->copy_relocs_.emit(this->rela_dyn_section(layout));
// Fill in some more dynamic tags.
Output_data_dynamic* const odyn = layout->dynamic_data();
if (odyn != NULL)
{
if (this->plt_ != NULL
&& this->plt_->output_section() != NULL
&& this->plt_ ->has_tlsdesc_entry())
{
unsigned int plt_offset = this->plt_->get_tlsdesc_plt_offset();
unsigned int got_offset = this->plt_->get_tlsdesc_got_offset();
this->got_->finalize_data_size();
odyn->add_section_plus_offset(elfcpp::DT_TLSDESC_PLT,
this->plt_, plt_offset);
odyn->add_section_plus_offset(elfcpp::DT_TLSDESC_GOT,
this->got_, got_offset);
}
}
// Set the size of the _GLOBAL_OFFSET_TABLE_ symbol to the size of
// the .got.plt section.
Symbol* sym = this->global_offset_table_;
if (sym != NULL)
{
uint64_t data_size = this->got_plt_->current_data_size();
symtab->get_sized_symbol<size>(sym)->set_symsize(data_size);
// If the .got section is more than 0x8000 bytes, we add
// 0x8000 to the value of _GLOBAL_OFFSET_TABLE_, so that 16
// bit relocations have a greater chance of working.
if (data_size >= 0x8000)
symtab->get_sized_symbol<size>(sym)->set_value(
symtab->get_sized_symbol<size>(sym)->value() + 0x8000);
}
if (parameters->doing_static_link()
&& (this->plt_ == NULL || !this->plt_->has_irelative_section()))
{
// If linking statically, make sure that the __rela_iplt symbols
// were defined if necessary, even if we didn't create a PLT.
static const Define_symbol_in_segment syms[] =
{
{
"__rela_iplt_start", // name
elfcpp::PT_LOAD, // segment_type
elfcpp::PF_W, // segment_flags_set
elfcpp::PF(0), // segment_flags_clear
0, // value
0, // size
elfcpp::STT_NOTYPE, // type
elfcpp::STB_GLOBAL, // binding
elfcpp::STV_HIDDEN, // visibility
0, // nonvis
Symbol::SEGMENT_START, // offset_from_base
true // only_if_ref
},
{
"__rela_iplt_end", // name
elfcpp::PT_LOAD, // segment_type
elfcpp::PF_W, // segment_flags_set
elfcpp::PF(0), // segment_flags_clear
0, // value
0, // size
elfcpp::STT_NOTYPE, // type
elfcpp::STB_GLOBAL, // binding
elfcpp::STV_HIDDEN, // visibility
0, // nonvis
Symbol::SEGMENT_START, // offset_from_base
true // only_if_ref
}
};
symtab->define_symbols(layout, 2, syms,
layout->script_options()->saw_sections_clause());
}
return;
}
// Perform a relocation.
template<int size, bool big_endian>
inline bool
Target_aarch64<size, big_endian>::Relocate::relocate(
const Relocate_info<size, big_endian>* relinfo,
unsigned int,
Target_aarch64<size, big_endian>* target,
Output_section* ,
size_t relnum,
const unsigned char* preloc,
const Sized_symbol<size>* gsym,
const Symbol_value<size>* psymval,
unsigned char* view,
typename elfcpp::Elf_types<size>::Elf_Addr address,
section_size_type /* view_size */)
{
if (view == NULL)
return true;
typedef AArch64_relocate_functions<size, big_endian> Reloc;
const elfcpp::Rela<size, big_endian> rela(preloc);
unsigned int r_type = elfcpp::elf_r_type<size>(rela.get_r_info());
const AArch64_reloc_property* reloc_property =
aarch64_reloc_property_table->get_reloc_property(r_type);
if (reloc_property == NULL)
{
std::string reloc_name =
aarch64_reloc_property_table->reloc_name_in_error_message(r_type);
gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
_("cannot relocate %s in object file"),
reloc_name.c_str());
return true;
}
const Sized_relobj_file<size, big_endian>* object = relinfo->object;
// Pick the value to use for symbols defined in the PLT.
Symbol_value<size> symval;
if (gsym != NULL
&& gsym->use_plt_offset(reloc_property->reference_flags()))
{
symval.set_output_value(target->plt_address_for_global(gsym));
psymval = &symval;
}
else if (gsym == NULL && psymval->is_ifunc_symbol())
{
unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
if (object->local_has_plt_offset(r_sym))
{
symval.set_output_value(target->plt_address_for_local(object, r_sym));
psymval = &symval;
}
}
const elfcpp::Elf_Xword addend = rela.get_r_addend();
// Get the GOT offset if needed.
// For aarch64, the GOT pointer points to the start of the GOT section.
bool have_got_offset = false;
int got_offset = 0;
int got_base = (target->got_ != NULL
? (target->got_->current_data_size() >= 0x8000
? 0x8000 : 0)
: 0);
switch (r_type)
{
case elfcpp::R_AARCH64_MOVW_GOTOFF_G0:
case elfcpp::R_AARCH64_MOVW_GOTOFF_G0_NC:
case elfcpp::R_AARCH64_MOVW_GOTOFF_G1:
case elfcpp::R_AARCH64_MOVW_GOTOFF_G1_NC:
case elfcpp::R_AARCH64_MOVW_GOTOFF_G2:
case elfcpp::R_AARCH64_MOVW_GOTOFF_G2_NC:
case elfcpp::R_AARCH64_MOVW_GOTOFF_G3:
case elfcpp::R_AARCH64_GOTREL64:
case elfcpp::R_AARCH64_GOTREL32:
case elfcpp::R_AARCH64_GOT_LD_PREL19:
case elfcpp::R_AARCH64_LD64_GOTOFF_LO15:
case elfcpp::R_AARCH64_ADR_GOT_PAGE:
case elfcpp::R_AARCH64_LD64_GOT_LO12_NC:
case elfcpp::R_AARCH64_LD64_GOTPAGE_LO15:
if (gsym != NULL)
{
gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
got_offset = gsym->got_offset(GOT_TYPE_STANDARD) - got_base;
}
else
{
unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
gold_assert(object->local_has_got_offset(r_sym, GOT_TYPE_STANDARD));
got_offset = (object->local_got_offset(r_sym, GOT_TYPE_STANDARD)
- got_base);
}
have_got_offset = true;
break;
default:
break;
}
typename Reloc::Status reloc_status = Reloc::STATUS_OKAY;
typename elfcpp::Elf_types<size>::Elf_Addr value;
switch (r_type)
{
case elfcpp::R_AARCH64_NONE:
break;
case elfcpp::R_AARCH64_ABS64:
if (!parameters->options().apply_dynamic_relocs()
&& parameters->options().output_is_position_independent()
&& gsym != NULL
&& gsym->needs_dynamic_reloc(reloc_property->reference_flags())
&& !gsym->can_use_relative_reloc(false))
// We have generated an absolute dynamic relocation, so do not
// apply the relocation statically. (Works around bugs in older
// Android dynamic linkers.)
break;
reloc_status = Reloc::template rela_ua<64>(
view, object, psymval, addend, reloc_property);
break;
case elfcpp::R_AARCH64_ABS32:
if (!parameters->options().apply_dynamic_relocs()
&& parameters->options().output_is_position_independent()
&& gsym != NULL
&& gsym->needs_dynamic_reloc(reloc_property->reference_flags()))
// We have generated an absolute dynamic relocation, so do not
// apply the relocation statically. (Works around bugs in older
// Android dynamic linkers.)
break;
reloc_status = Reloc::template rela_ua<32>(
view, object, psymval, addend, reloc_property);
break;
case elfcpp::R_AARCH64_ABS16:
if (!parameters->options().apply_dynamic_relocs()
&& parameters->options().output_is_position_independent()
&& gsym != NULL
&& gsym->needs_dynamic_reloc(reloc_property->reference_flags()))
// We have generated an absolute dynamic relocation, so do not
// apply the relocation statically. (Works around bugs in older
// Android dynamic linkers.)
break;
reloc_status = Reloc::template rela_ua<16>(
view, object, psymval, addend, reloc_property);
break;
case elfcpp::R_AARCH64_PREL64:
reloc_status = Reloc::template pcrela_ua<64>(
view, object, psymval, addend, address, reloc_property);
break;
case elfcpp::R_AARCH64_PREL32:
reloc_status = Reloc::template pcrela_ua<32>(
view, object, psymval, addend, address, reloc_property);
break;
case elfcpp::R_AARCH64_PREL16:
reloc_status = Reloc::template pcrela_ua<16>(
view, object, psymval, addend, address, reloc_property);
break;
case elfcpp::R_AARCH64_LD_PREL_LO19:
reloc_status = Reloc::template pcrela_general<32>(
view, object, psymval, addend, address, reloc_property);
break;
case elfcpp::R_AARCH64_ADR_PREL_LO21:
reloc_status = Reloc::adr(view, object, psymval, addend,
address, reloc_property);
break;
case elfcpp::R_AARCH64_ADR_PREL_PG_HI21_NC:
case elfcpp::R_AARCH64_ADR_PREL_PG_HI21:
reloc_status = Reloc::adrp(view, object, psymval, addend, address,
reloc_property);
break;
case elfcpp::R_AARCH64_LDST8_ABS_LO12_NC:
case elfcpp::R_AARCH64_LDST16_ABS_LO12_NC:
case elfcpp::R_AARCH64_LDST32_ABS_LO12_NC:
case elfcpp::R_AARCH64_LDST64_ABS_LO12_NC:
case elfcpp::R_AARCH64_LDST128_ABS_LO12_NC:
case elfcpp::R_AARCH64_ADD_ABS_LO12_NC:
reloc_status = Reloc::template rela_general<32>(
view, object, psymval, addend, reloc_property);
break;
case elfcpp::R_AARCH64_CALL26:
if (this->skip_call_tls_get_addr_)
{
// Double check that the TLSGD insn has been optimized away.
typedef typename elfcpp::Swap<32, big_endian>::Valtype Insntype;
Insntype insn = elfcpp::Swap<32, big_endian>::readval(
reinterpret_cast<Insntype*>(view));
gold_assert((insn & 0xff000000) == 0x91000000);
reloc_status = Reloc::STATUS_OKAY;
this->skip_call_tls_get_addr_ = false;
// Return false to stop further processing this reloc.
return false;
}
// Fallthrough
case elfcpp::R_AARCH64_JUMP26:
if (Reloc::maybe_apply_stub(r_type, relinfo, rela, view, address,
gsym, psymval, object,
target->stub_group_size_))
break;
// Fallthrough
case elfcpp::R_AARCH64_TSTBR14:
case elfcpp::R_AARCH64_CONDBR19:
reloc_status = Reloc::template pcrela_general<32>(
view, object, psymval, addend, address, reloc_property);
break;
case elfcpp::R_AARCH64_ADR_GOT_PAGE:
gold_assert(have_got_offset);
value = target->got_->address() + got_base + got_offset;
reloc_status = Reloc::adrp(view, value + addend, address);
break;
case elfcpp::R_AARCH64_LD64_GOT_LO12_NC:
gold_assert(have_got_offset);
value = target->got_->address() + got_base + got_offset;
reloc_status = Reloc::template rela_general<32>(
view, value, addend, reloc_property);
break;
case elfcpp::R_AARCH64_TLSGD_ADR_PAGE21:
case elfcpp::R_AARCH64_TLSGD_ADD_LO12_NC:
case elfcpp::R_AARCH64_TLSLD_ADR_PAGE21:
case elfcpp::R_AARCH64_TLSLD_ADD_LO12_NC:
case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G1:
case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G0_NC:
case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_HI12:
case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_LO12_NC:
case elfcpp::R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21:
case elfcpp::R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC:
case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G2:
case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G1:
case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G1_NC:
case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G0:
case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G0_NC:
case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_HI12:
case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12:
case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12_NC:
case elfcpp::R_AARCH64_TLSDESC_ADR_PAGE21:
case elfcpp::R_AARCH64_TLSDESC_LD64_LO12:
case elfcpp::R_AARCH64_TLSDESC_ADD_LO12:
case elfcpp::R_AARCH64_TLSDESC_CALL:
reloc_status = relocate_tls(relinfo, target, relnum, rela, r_type,
gsym, psymval, view, address);
break;
// These are dynamic relocations, which are unexpected when linking.
case elfcpp::R_AARCH64_COPY:
case elfcpp::R_AARCH64_GLOB_DAT:
case elfcpp::R_AARCH64_JUMP_SLOT:
case elfcpp::R_AARCH64_RELATIVE:
case elfcpp::R_AARCH64_IRELATIVE:
case elfcpp::R_AARCH64_TLS_DTPREL64:
case elfcpp::R_AARCH64_TLS_DTPMOD64:
case elfcpp::R_AARCH64_TLS_TPREL64:
case elfcpp::R_AARCH64_TLSDESC:
gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
_("unexpected reloc %u in object file"),
r_type);
break;
default:
gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
_("unsupported reloc %s"),
reloc_property->name().c_str());
break;
}
// Report any errors.
switch (reloc_status)
{
case Reloc::STATUS_OKAY:
break;
case Reloc::STATUS_OVERFLOW:
gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
_("relocation overflow in %s"),
reloc_property->name().c_str());
break;
case Reloc::STATUS_BAD_RELOC:
gold_error_at_location(
relinfo,
relnum,
rela.get_r_offset(),
_("unexpected opcode while processing relocation %s"),
reloc_property->name().c_str());
break;
default:
gold_unreachable();
}
return true;
}
template<int size, bool big_endian>
inline
typename AArch64_relocate_functions<size, big_endian>::Status
Target_aarch64<size, big_endian>::Relocate::relocate_tls(
const Relocate_info<size, big_endian>* relinfo,
Target_aarch64<size, big_endian>* target,
size_t relnum,
const elfcpp::Rela<size, big_endian>& rela,
unsigned int r_type, const Sized_symbol<size>* gsym,
const Symbol_value<size>* psymval,
unsigned char* view,
typename elfcpp::Elf_types<size>::Elf_Addr address)
{
typedef AArch64_relocate_functions<size, big_endian> aarch64_reloc_funcs;
typedef typename elfcpp::Elf_types<size>::Elf_Addr AArch64_address;
Output_segment* tls_segment = relinfo->layout->tls_segment();
const elfcpp::Elf_Xword addend = rela.get_r_addend();
const AArch64_reloc_property* reloc_property =
aarch64_reloc_property_table->get_reloc_property(r_type);
gold_assert(reloc_property != NULL);
const bool is_final = (gsym == NULL
? !parameters->options().shared()
: gsym->final_value_is_known());
tls::Tls_optimization tlsopt = Target_aarch64<size, big_endian>::
optimize_tls_reloc(is_final, r_type);
Sized_relobj_file<size, big_endian>* object = relinfo->object;
int tls_got_offset_type;
switch (r_type)
{
case elfcpp::R_AARCH64_TLSGD_ADR_PAGE21:
case elfcpp::R_AARCH64_TLSGD_ADD_LO12_NC: // Global-dynamic
{
if (tlsopt == tls::TLSOPT_TO_LE)
{
if (tls_segment == NULL)
{
gold_assert(parameters->errors()->error_count() > 0
|| issue_undefined_symbol_error(gsym));
return aarch64_reloc_funcs::STATUS_BAD_RELOC;
}
return tls_gd_to_le(relinfo, target, rela, r_type, view,
psymval);
}
else if (tlsopt == tls::TLSOPT_NONE)
{
tls_got_offset_type = GOT_TYPE_TLS_PAIR;
// Firstly get the address for the got entry.
typename elfcpp::Elf_types<size>::Elf_Addr got_entry_address;
if (gsym != NULL)
{
gold_assert(gsym->has_got_offset(tls_got_offset_type));
got_entry_address = target->got_->address() +
gsym->got_offset(tls_got_offset_type);
}
else
{
unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
gold_assert(
object->local_has_got_offset(r_sym, tls_got_offset_type));
got_entry_address = target->got_->address() +
object->local_got_offset(r_sym, tls_got_offset_type);
}
// Relocate the address into adrp/ld, adrp/add pair.
switch (r_type)
{
case elfcpp::R_AARCH64_TLSGD_ADR_PAGE21:
return aarch64_reloc_funcs::adrp(
view, got_entry_address + addend, address);
break;
case elfcpp::R_AARCH64_TLSGD_ADD_LO12_NC:
return aarch64_reloc_funcs::template rela_general<32>(
view, got_entry_address, addend, reloc_property);
break;
default:
gold_unreachable();
}
}
gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
_("unsupported gd_to_ie relaxation on %u"),
r_type);
}
break;
case elfcpp::R_AARCH64_TLSLD_ADR_PAGE21:
case elfcpp::R_AARCH64_TLSLD_ADD_LO12_NC: // Local-dynamic
{
if (tlsopt == tls::TLSOPT_TO_LE)
{
if (tls_segment == NULL)
{
gold_assert(parameters->errors()->error_count() > 0
|| issue_undefined_symbol_error(gsym));
return aarch64_reloc_funcs::STATUS_BAD_RELOC;
}
return this->tls_ld_to_le(relinfo, target, rela, r_type, view,
psymval);
}
gold_assert(tlsopt == tls::TLSOPT_NONE);
// Relocate the field with the offset of the GOT entry for
// the module index.
typename elfcpp::Elf_types<size>::Elf_Addr got_entry_address;
got_entry_address = (target->got_mod_index_entry(NULL, NULL, NULL) +
target->got_->address());
switch (r_type)
{
case elfcpp::R_AARCH64_TLSLD_ADR_PAGE21:
return aarch64_reloc_funcs::adrp(
view, got_entry_address + addend, address);
break;
case elfcpp::R_AARCH64_TLSLD_ADD_LO12_NC:
return aarch64_reloc_funcs::template rela_general<32>(
view, got_entry_address, addend, reloc_property);
break;
default:
gold_unreachable();
}
}
break;
case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G1:
case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G0_NC:
case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_HI12:
case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_LO12_NC: // Other local-dynamic
{
AArch64_address value = psymval->value(object, 0);
if (tlsopt == tls::TLSOPT_TO_LE)
{
if (tls_segment == NULL)
{
gold_assert(parameters->errors()->error_count() > 0
|| issue_undefined_symbol_error(gsym));
return aarch64_reloc_funcs::STATUS_BAD_RELOC;
}
}
switch (r_type)
{
case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G1:
return aarch64_reloc_funcs::movnz(view, value + addend,
reloc_property);
break;
case elfcpp::R_AARCH64_TLSLD_MOVW_DTPREL_G0_NC:
case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_HI12:
case elfcpp::R_AARCH64_TLSLD_ADD_DTPREL_LO12_NC:
return aarch64_reloc_funcs::template rela_general<32>(
view, value, addend, reloc_property);
break;
default:
gold_unreachable();
}
// We should never reach here.
}
break;
case elfcpp::R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21:
case elfcpp::R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC: // Initial-exec
{
if (tlsopt == tls::TLSOPT_TO_LE)
{
if (tls_segment == NULL)
{
gold_assert(parameters->errors()->error_count() > 0
|| issue_undefined_symbol_error(gsym));
return aarch64_reloc_funcs::STATUS_BAD_RELOC;
}
return tls_ie_to_le(relinfo, target, rela, r_type, view,
psymval);
}
tls_got_offset_type = GOT_TYPE_TLS_OFFSET;
// Firstly get the address for the got entry.
typename elfcpp::Elf_types<size>::Elf_Addr got_entry_address;
if (gsym != NULL)
{
gold_assert(gsym->has_got_offset(tls_got_offset_type));
got_entry_address = target->got_->address() +
gsym->got_offset(tls_got_offset_type);
}
else
{
unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
gold_assert(
object->local_has_got_offset(r_sym, tls_got_offset_type));
got_entry_address = target->got_->address() +
object->local_got_offset(r_sym, tls_got_offset_type);
}
// Relocate the address into adrp/ld, adrp/add pair.
switch (r_type)
{
case elfcpp::R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21:
return aarch64_reloc_funcs::adrp(view, got_entry_address + addend,
address);
break;
case elfcpp::R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC:
return aarch64_reloc_funcs::template rela_general<32>(
view, got_entry_address, addend, reloc_property);
default:
gold_unreachable();
}
}
// We shall never reach here.
break;
case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G2:
case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G1:
case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G1_NC:
case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G0:
case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G0_NC:
case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_HI12:
case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12:
case elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12_NC:
{
gold_assert(tls_segment != NULL);
AArch64_address value = psymval->value(object, 0);
if (!parameters->options().shared())
{
AArch64_address aligned_tcb_size =
align_address(target->tcb_size(),
tls_segment->maximum_alignment());
value += aligned_tcb_size;
switch (r_type)
{
case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G2:
case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G1:
case elfcpp::R_AARCH64_TLSLE_MOVW_TPREL_G0:
return aarch64_reloc_funcs::movnz(view, value + addend,
reloc_property);
default:
return aarch64_reloc_funcs::template
rela_general<32>(view,
value,
addend,
reloc_property);
}
}
else
gold_error(_("%s: unsupported reloc %u "
"in non-static TLSLE mode."),
object->name().c_str(), r_type);
}
break;
case elfcpp::R_AARCH64_TLSDESC_ADR_PAGE21:
case elfcpp::R_AARCH64_TLSDESC_LD64_LO12:
case elfcpp::R_AARCH64_TLSDESC_ADD_LO12:
case elfcpp::R_AARCH64_TLSDESC_CALL:
{
if (tlsopt == tls::TLSOPT_TO_LE)
{
if (tls_segment == NULL)
{
gold_assert(parameters->errors()->error_count() > 0
|| issue_undefined_symbol_error(gsym));
return aarch64_reloc_funcs::STATUS_BAD_RELOC;
}
return tls_desc_gd_to_le(relinfo, target, rela, r_type,
view, psymval);
}
else
{
tls_got_offset_type = (tlsopt == tls::TLSOPT_TO_IE
? GOT_TYPE_TLS_OFFSET
: GOT_TYPE_TLS_DESC);
unsigned int got_tlsdesc_offset = 0;
if (r_type != elfcpp::R_AARCH64_TLSDESC_CALL
&& tlsopt == tls::TLSOPT_NONE)
{
// We created GOT entries in the .got.tlsdesc portion of the
// .got.plt section, but the offset stored in the symbol is the
// offset within .got.tlsdesc.
got_tlsdesc_offset = (target->got_->data_size()
+ target->got_plt_section()->data_size());
}
typename elfcpp::Elf_types<size>::Elf_Addr got_entry_address;
if (gsym != NULL)
{
gold_assert(gsym->has_got_offset(tls_got_offset_type));
got_entry_address = target->got_->address()
+ got_tlsdesc_offset
+ gsym->got_offset(tls_got_offset_type);
}
else
{
unsigned int r_sym = elfcpp::elf_r_sym<size>(rela.get_r_info());
gold_assert(
object->local_has_got_offset(r_sym, tls_got_offset_type));
got_entry_address = target->got_->address() +
got_tlsdesc_offset +
object->local_got_offset(r_sym, tls_got_offset_type);
}
if (tlsopt == tls::TLSOPT_TO_IE)
{
if (tls_segment == NULL)
{
gold_assert(parameters->errors()->error_count() > 0
|| issue_undefined_symbol_error(gsym));
return aarch64_reloc_funcs::STATUS_BAD_RELOC;
}
return tls_desc_gd_to_ie(relinfo, target, rela, r_type,
view, psymval, got_entry_address,
address);
}
// Now do tlsdesc relocation.
switch (r_type)
{
case elfcpp::R_AARCH64_TLSDESC_ADR_PAGE21:
return aarch64_reloc_funcs::adrp(view,
got_entry_address + addend,
address);
break;
case elfcpp::R_AARCH64_TLSDESC_LD64_LO12:
case elfcpp::R_AARCH64_TLSDESC_ADD_LO12:
return aarch64_reloc_funcs::template rela_general<32>(
view, got_entry_address, addend, reloc_property);
break;
case elfcpp::R_AARCH64_TLSDESC_CALL:
return aarch64_reloc_funcs::STATUS_OKAY;
break;
default:
gold_unreachable();
}
}
}
break;
default:
gold_error(_("%s: unsupported TLS reloc %u."),
object->name().c_str(), r_type);
}
return aarch64_reloc_funcs::STATUS_BAD_RELOC;
} // End of relocate_tls.
template<int size, bool big_endian>
inline
typename AArch64_relocate_functions<size, big_endian>::Status
Target_aarch64<size, big_endian>::Relocate::tls_gd_to_le(
const Relocate_info<size, big_endian>* relinfo,
Target_aarch64<size, big_endian>* target,
const elfcpp::Rela<size, big_endian>& rela,
unsigned int r_type,
unsigned char* view,
const Symbol_value<size>* psymval)
{
typedef AArch64_relocate_functions<size, big_endian> aarch64_reloc_funcs;
typedef typename elfcpp::Swap<32, big_endian>::Valtype Insntype;
typedef typename elfcpp::Elf_types<size>::Elf_Addr AArch64_address;
Insntype* ip = reinterpret_cast<Insntype*>(view);
Insntype insn1 = elfcpp::Swap<32, big_endian>::readval(ip);
Insntype insn2 = elfcpp::Swap<32, big_endian>::readval(ip + 1);
Insntype insn3 = elfcpp::Swap<32, big_endian>::readval(ip + 2);
if (r_type == elfcpp::R_AARCH64_TLSGD_ADD_LO12_NC)
{
// This is the 2nd relocs, optimization should already have been
// done.
gold_assert((insn1 & 0xfff00000) == 0x91400000);
return aarch64_reloc_funcs::STATUS_OKAY;
}
// The original sequence is -
// 90000000 adrp x0, 0 <main>
// 91000000 add x0, x0, #0x0
// 94000000 bl 0 <__tls_get_addr>
// optimized to sequence -
// d53bd040 mrs x0, tpidr_el0
// 91400000 add x0, x0, #0x0, lsl #12
// 91000000 add x0, x0, #0x0
// Unlike tls_ie_to_le, we change the 3 insns in one function call when we
// encounter the first relocation "R_AARCH64_TLSGD_ADR_PAGE21". Because we
// have to change "bl tls_get_addr", which does not have a corresponding tls
// relocation type. So before proceeding, we need to make sure compiler
// does not change the sequence.
if(!(insn1 == 0x90000000 // adrp x0,0
&& insn2 == 0x91000000 // add x0, x0, #0x0
&& insn3 == 0x94000000)) // bl 0
{
// Ideally we should give up gd_to_le relaxation and do gd access.
// However the gd_to_le relaxation decision has been made early
// in the scan stage, where we did not allocate any GOT entry for
// this symbol. Therefore we have to exit and report error now.
gold_error(_("unexpected reloc insn sequence while relaxing "
"tls gd to le for reloc %u."), r_type);
return aarch64_reloc_funcs::STATUS_BAD_RELOC;
}
// Write new insns.
insn1 = 0xd53bd040; // mrs x0, tpidr_el0
insn2 = 0x91400000; // add x0, x0, #0x0, lsl #12
insn3 = 0x91000000; // add x0, x0, #0x0
elfcpp::Swap<32, big_endian>::writeval(ip, insn1);
elfcpp::Swap<32, big_endian>::writeval(ip + 1, insn2);
elfcpp::Swap<32, big_endian>::writeval(ip + 2, insn3);
// Calculate tprel value.
Output_segment* tls_segment = relinfo->layout->tls_segment();
gold_assert(tls_segment != NULL);
AArch64_address value = psymval->value(relinfo->object, 0);
const elfcpp::Elf_Xword addend = rela.get_r_addend();
AArch64_address aligned_tcb_size =
align_address(target->tcb_size(), tls_segment->maximum_alignment());
AArch64_address x = value + aligned_tcb_size;
// After new insns are written, apply TLSLE relocs.
const AArch64_reloc_property* rp1 =
aarch64_reloc_property_table->get_reloc_property(
elfcpp::R_AARCH64_TLSLE_ADD_TPREL_HI12);
const AArch64_reloc_property* rp2 =
aarch64_reloc_property_table->get_reloc_property(
elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12);
gold_assert(rp1 != NULL && rp2 != NULL);
typename aarch64_reloc_funcs::Status s1 =
aarch64_reloc_funcs::template rela_general<32>(view + 4,
x,
addend,
rp1);
if (s1 != aarch64_reloc_funcs::STATUS_OKAY)
return s1;
typename aarch64_reloc_funcs::Status s2 =
aarch64_reloc_funcs::template rela_general<32>(view + 8,
x,
addend,
rp2);
this->skip_call_tls_get_addr_ = true;
return s2;
} // End of tls_gd_to_le
template<int size, bool big_endian>
inline
typename AArch64_relocate_functions<size, big_endian>::Status
Target_aarch64<size, big_endian>::Relocate::tls_ld_to_le(
const Relocate_info<size, big_endian>* relinfo,
Target_aarch64<size, big_endian>* target,
const elfcpp::Rela<size, big_endian>& rela,
unsigned int r_type,
unsigned char* view,
const Symbol_value<size>* psymval)
{
typedef AArch64_relocate_functions<size, big_endian> aarch64_reloc_funcs;
typedef typename elfcpp::Swap<32, big_endian>::Valtype Insntype;
typedef typename elfcpp::Elf_types<size>::Elf_Addr AArch64_address;
Insntype* ip = reinterpret_cast<Insntype*>(view);
Insntype insn1 = elfcpp::Swap<32, big_endian>::readval(ip);
Insntype insn2 = elfcpp::Swap<32, big_endian>::readval(ip + 1);
Insntype insn3 = elfcpp::Swap<32, big_endian>::readval(ip + 2);
if (r_type == elfcpp::R_AARCH64_TLSLD_ADD_LO12_NC)
{
// This is the 2nd relocs, optimization should already have been
// done.
gold_assert((insn1 & 0xfff00000) == 0x91400000);
return aarch64_reloc_funcs::STATUS_OKAY;
}
// The original sequence is -
// 90000000 adrp x0, 0 <main>
// 91000000 add x0, x0, #0x0
// 94000000 bl 0 <__tls_get_addr>
// optimized to sequence -
// d53bd040 mrs x0, tpidr_el0
// 91400000 add x0, x0, #0x0, lsl #12
// 91000000 add x0, x0, #0x0
// Unlike tls_ie_to_le, we change the 3 insns in one function call when we
// encounter the first relocation "R_AARCH64_TLSLD_ADR_PAGE21". Because we
// have to change "bl tls_get_addr", which does not have a corresponding tls
// relocation type. So before proceeding, we need to make sure compiler
// does not change the sequence.
if(!(insn1 == 0x90000000 // adrp x0,0
&& insn2 == 0x91000000 // add x0, x0, #0x0
&& insn3 == 0x94000000)) // bl 0
{
// Ideally we should give up gd_to_le relaxation and do gd access.
// However the gd_to_le relaxation decision has been made early
// in the scan stage, where we did not allocate any GOT entry for
// this symbol. Therefore we have to exit and report error now.
gold_error(_("unexpected reloc insn sequence while relaxing "
"tls gd to le for reloc %u."), r_type);
return aarch64_reloc_funcs::STATUS_BAD_RELOC;
}
// Write new insns.
insn1 = 0xd53bd040; // mrs x0, tpidr_el0
insn2 = 0x91400000; // add x0, x0, #0x0, lsl #12
insn3 = 0x91000000; // add x0, x0, #0x0
elfcpp::Swap<32, big_endian>::writeval(ip, insn1);
elfcpp::Swap<32, big_endian>::writeval(ip + 1, insn2);
elfcpp::Swap<32, big_endian>::writeval(ip + 2, insn3);
// Calculate tprel value.
Output_segment* tls_segment = relinfo->layout->tls_segment();
gold_assert(tls_segment != NULL);
AArch64_address value = psymval->value(relinfo->object, 0);
const elfcpp::Elf_Xword addend = rela.get_r_addend();
AArch64_address aligned_tcb_size =
align_address(target->tcb_size(), tls_segment->maximum_alignment());
AArch64_address x = value + aligned_tcb_size;
// After new insns are written, apply TLSLE relocs.
const AArch64_reloc_property* rp1 =
aarch64_reloc_property_table->get_reloc_property(
elfcpp::R_AARCH64_TLSLE_ADD_TPREL_HI12);
const AArch64_reloc_property* rp2 =
aarch64_reloc_property_table->get_reloc_property(
elfcpp::R_AARCH64_TLSLE_ADD_TPREL_LO12);
gold_assert(rp1 != NULL && rp2 != NULL);
typename aarch64_reloc_funcs::Status s1 =
aarch64_reloc_funcs::template rela_general<32>(view + 4,
x,
addend,
rp1);
if (s1 != aarch64_reloc_funcs::STATUS_OKAY)
return s1;
typename aarch64_reloc_funcs::Status s2 =
aarch64_reloc_funcs::template rela_general<32>(view + 8,
x,
addend,
rp2);
this->skip_call_tls_get_addr_ = true;
return s2;
} // End of tls_ld_to_le
template<int size, bool big_endian>
inline
typename AArch64_relocate_functions<size, big_endian>::Status
Target_aarch64<size, big_endian>::Relocate::tls_ie_to_le(
const Relocate_info<size, big_endian>* relinfo,
Target_aarch64<size, big_endian>* target,
const elfcpp::Rela<size, big_endian>& rela,
unsigned int r_type,
unsigned char* view,
const Symbol_value<size>* psymval)
{
typedef typename elfcpp::Elf_types<size>::Elf_Addr AArch64_address;
typedef typename elfcpp::Swap<32, big_endian>::Valtype Insntype;
typedef AArch64_relocate_functions<size, big_endian> aarch64_reloc_funcs;
AArch64_address value = psymval->value(relinfo->object, 0);
Output_segment* tls_segment = relinfo->layout->tls_segment();
AArch64_address aligned_tcb_address =
align_address(target->tcb_size(), tls_segment->maximum_alignment());
const elfcpp::Elf_Xword addend = rela.get_r_addend();
AArch64_address x = value + addend + aligned_tcb_address;
// "x" is the offset to tp, we can only do this if x is within
// range [0, 2^32-1]
if (!(size == 32 || (size == 64 && (static_cast<uint64_t>(x) >> 32) == 0)))
{
gold_error(_("TLS variable referred by reloc %u is too far from TP."),
r_type);
return aarch64_reloc_funcs::STATUS_BAD_RELOC;
}
Insntype* ip = reinterpret_cast<Insntype*>(view);
Insntype insn = elfcpp::Swap<32, big_endian>::readval(ip);
unsigned int regno;
Insntype newinsn;
if (r_type == elfcpp::R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21)
{
// Generate movz.
regno = (insn & 0x1f);
newinsn = (0xd2a00000 | regno) | (((x >> 16) & 0xffff) << 5);
}
else if (r_type == elfcpp::R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC)
{
// Generate movk.
regno = (insn & 0x1f);
gold_assert(regno == ((insn >> 5) & 0x1f));
newinsn = (0xf2800000 | regno) | ((x & 0xffff) << 5);
}
else
gold_unreachable();
elfcpp::Swap<32, big_endian>::writeval(ip, newinsn);
return aarch64_reloc_funcs::STATUS_OKAY;
} // End of tls_ie_to_le
template<int size, bool big_endian>
inline
typename AArch64_relocate_functions<size, big_endian>::Status
Target_aarch64<size, big_endian>::Relocate::tls_desc_gd_to_le(
const Relocate_info<size, big_endian>* relinfo,
Target_aarch64<size, big_endian>* target,
const elfcpp::Rela<size, big_endian>& rela,
unsigned int r_type,
unsigned char* view,
const Symbol_value<size>* psymval)
{
typedef typename elfcpp::Elf_types<size>::Elf_Addr AArch64_address;
typedef typename elfcpp::Swap<32, big_endian>::Valtype Insntype;
typedef AArch64_relocate_functions<size, big_endian> aarch64_reloc_funcs;
// TLSDESC-GD sequence is like:
// adrp x0, :tlsdesc:v1
// ldr x1, [x0, #:tlsdesc_lo12:v1]
// add x0, x0, :tlsdesc_lo12:v1
// .tlsdesccall v1
// blr x1
// After desc_gd_to_le optimization, the sequence will be like:
// movz x0, #0x0, lsl #16
// movk x0, #0x10
// nop
// nop
// Calculate tprel value.
Output_segment* tls_segment = relinfo->layout->tls_segment();
gold_assert(tls_segment != NULL);
Insntype* ip = reinterpret_cast<Insntype*>(view);
const elfcpp::Elf_Xword addend = rela.get_r_addend();
AArch64_address value = psymval->value(relinfo->object, addend);
AArch64_address aligned_tcb_size =
align_address(target->tcb_size(), tls_segment->maximum_alignment());
AArch64_address x = value + aligned_tcb_size;
// x is the offset to tp, we can only do this if x is within range
// [0, 2^32-1]. If x is out of range, fail and exit.
if (size == 64 && (static_cast<uint64_t>(x) >> 32) != 0)
{
gold_error(_("TLS variable referred by reloc %u is too far from TP. "
"We Can't do gd_to_le relaxation.\n"), r_type);
return aarch64_reloc_funcs::STATUS_BAD_RELOC;
}
Insntype newinsn;
switch (r_type)
{
case elfcpp::R_AARCH64_TLSDESC_ADD_LO12:
case elfcpp::R_AARCH64_TLSDESC_CALL:
// Change to nop
newinsn = 0xd503201f;
break;
case elfcpp::R_AARCH64_TLSDESC_ADR_PAGE21:
// Change to movz.
newinsn = 0xd2a00000 | (((x >> 16) & 0xffff) << 5);
break;
case elfcpp::R_AARCH64_TLSDESC_LD64_LO12:
// Change to movk.
newinsn = 0xf2800000 | ((x & 0xffff) << 5);
break;
default:
gold_error(_("unsupported tlsdesc gd_to_le optimization on reloc %u"),
r_type);
gold_unreachable();
}
elfcpp::Swap<32, big_endian>::writeval(ip, newinsn);
return aarch64_reloc_funcs::STATUS_OKAY;
} // End of tls_desc_gd_to_le
template<int size, bool big_endian>
inline
typename AArch64_relocate_functions<size, big_endian>::Status
Target_aarch64<size, big_endian>::Relocate::tls_desc_gd_to_ie(
const Relocate_info<size, big_endian>* /* relinfo */,
Target_aarch64<size, big_endian>* /* target */,
const elfcpp::Rela<size, big_endian>& rela,
unsigned int r_type,
unsigned char* view,
const Symbol_value<size>* /* psymval */,
typename elfcpp::Elf_types<size>::Elf_Addr got_entry_address,
typename elfcpp::Elf_types<size>::Elf_Addr address)
{
typedef typename elfcpp::Swap<32, big_endian>::Valtype Insntype;
typedef AArch64_relocate_functions<size, big_endian> aarch64_reloc_funcs;
// TLSDESC-GD sequence is like:
// adrp x0, :tlsdesc:v1
// ldr x1, [x0, #:tlsdesc_lo12:v1]
// add x0, x0, :tlsdesc_lo12:v1
// .tlsdesccall v1
// blr x1
// After desc_gd_to_ie optimization, the sequence will be like:
// adrp x0, :tlsie:v1
// ldr x0, [x0, :tlsie_lo12:v1]
// nop
// nop
Insntype* ip = reinterpret_cast<Insntype*>(view);
const elfcpp::Elf_Xword addend = rela.get_r_addend();
Insntype newinsn;
switch (r_type)
{
case elfcpp::R_AARCH64_TLSDESC_ADD_LO12:
case elfcpp::R_AARCH64_TLSDESC_CALL:
// Change to nop
newinsn = 0xd503201f;
elfcpp::Swap<32, big_endian>::writeval(ip, newinsn);
break;
case elfcpp::R_AARCH64_TLSDESC_ADR_PAGE21:
{
return aarch64_reloc_funcs::adrp(view, got_entry_address + addend,
address);
}
break;
case elfcpp::R_AARCH64_TLSDESC_LD64_LO12:
{
// Set ldr target register to be x0.
Insntype insn = elfcpp::Swap<32, big_endian>::readval(ip);
insn &= 0xffffffe0;
elfcpp::Swap<32, big_endian>::writeval(ip, insn);
// Do relocation.
const AArch64_reloc_property* reloc_property =
aarch64_reloc_property_table->get_reloc_property(
elfcpp::R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC);
return aarch64_reloc_funcs::template rela_general<32>(
view, got_entry_address, addend, reloc_property);
}
break;
default:
gold_error(_("Don't support tlsdesc gd_to_ie optimization on reloc %u"),
r_type);
gold_unreachable();
}
return aarch64_reloc_funcs::STATUS_OKAY;
} // End of tls_desc_gd_to_ie
// Relocate section data.
template<int size, bool big_endian>
void
Target_aarch64<size, big_endian>::relocate_section(
const Relocate_info<size, big_endian>* relinfo,
unsigned int sh_type,
const unsigned char* prelocs,
size_t reloc_count,
Output_section* output_section,
bool needs_special_offset_handling,
unsigned char* view,
typename elfcpp::Elf_types<size>::Elf_Addr address,
section_size_type view_size,
const Reloc_symbol_changes* reloc_symbol_changes)
{
gold_assert(sh_type == elfcpp::SHT_RELA);
typedef typename Target_aarch64<size, big_endian>::Relocate AArch64_relocate;
gold::relocate_section<size, big_endian, Target_aarch64, elfcpp::SHT_RELA,
AArch64_relocate, gold::Default_comdat_behavior>(
relinfo,
this,
prelocs,
reloc_count,
output_section,
needs_special_offset_handling,
view,
address,
view_size,
reloc_symbol_changes);
}
// Return the size of a relocation while scanning during a relocatable
// link.
template<int size, bool big_endian>
unsigned int
Target_aarch64<size, big_endian>::Relocatable_size_for_reloc::
get_size_for_reloc(
unsigned int ,
Relobj* )
{
// We will never support SHT_REL relocations.
gold_unreachable();
return 0;
}
// Scan the relocs during a relocatable link.
template<int size, bool big_endian>
void
Target_aarch64<size, big_endian>::scan_relocatable_relocs(
Symbol_table* symtab,
Layout* layout,
Sized_relobj_file<size, big_endian>* object,
unsigned int data_shndx,
unsigned int sh_type,
const unsigned char* prelocs,
size_t reloc_count,
Output_section* output_section,
bool needs_special_offset_handling,
size_t local_symbol_count,
const unsigned char* plocal_symbols,
Relocatable_relocs* rr)
{
gold_assert(sh_type == elfcpp::SHT_RELA);
typedef gold::Default_scan_relocatable_relocs<elfcpp::SHT_RELA,
Relocatable_size_for_reloc> Scan_relocatable_relocs;
gold::scan_relocatable_relocs<size, big_endian, elfcpp::SHT_RELA,
Scan_relocatable_relocs>(
symtab,
layout,
object,
data_shndx,
prelocs,
reloc_count,
output_section,
needs_special_offset_handling,
local_symbol_count,
plocal_symbols,
rr);
}
// Relocate a section during a relocatable link.
template<int size, bool big_endian>
void
Target_aarch64<size, big_endian>::relocate_relocs(
const Relocate_info<size, big_endian>* relinfo,
unsigned int sh_type,
const unsigned char* prelocs,
size_t reloc_count,
Output_section* output_section,
typename elfcpp::Elf_types<size>::Elf_Off offset_in_output_section,
unsigned char* view,
typename elfcpp::Elf_types<size>::Elf_Addr view_address,
section_size_type view_size,
unsigned char* reloc_view,
section_size_type reloc_view_size)
{
gold_assert(sh_type == elfcpp::SHT_RELA);
gold::relocate_relocs<size, big_endian, elfcpp::SHT_RELA>(
relinfo,
prelocs,
reloc_count,
output_section,
offset_in_output_section,
view,
view_address,
view_size,
reloc_view,
reloc_view_size);
}
// Return whether this is a 3-insn erratum sequence.
template<int size, bool big_endian>
bool
Target_aarch64<size, big_endian>::is_erratum_843419_sequence(
typename elfcpp::Swap<32,big_endian>::Valtype insn1,
typename elfcpp::Swap<32,big_endian>::Valtype insn2,
typename elfcpp::Swap<32,big_endian>::Valtype insn3)
{
unsigned rt1, rt2;
bool load, pair;
// The 2nd insn is a single register load or store; or register pair
// store.
if (Insn_utilities::aarch64_mem_op_p(insn2, &rt1, &rt2, &pair, &load)
&& (!pair || (pair && !load)))
{
// The 3rd insn is a load or store instruction from the "Load/store
// register (unsigned immediate)" encoding class, using Rn as the
// base address register.
if (Insn_utilities::aarch64_ldst_uimm(insn3)
&& (Insn_utilities::aarch64_rn(insn3)
== Insn_utilities::aarch64_rd(insn1)))
return true;
}
return false;
}
// Return whether this is a 835769 sequence.
// (Similarly implemented as in elfnn-aarch64.c.)
template<int size, bool big_endian>
bool
Target_aarch64<size, big_endian>::is_erratum_835769_sequence(
typename elfcpp::Swap<32,big_endian>::Valtype insn1,
typename elfcpp::Swap<32,big_endian>::Valtype insn2)
{
uint32_t rt;
uint32_t rt2;
uint32_t rn;
uint32_t rm;
uint32_t ra;
bool pair;
bool load;
if (Insn_utilities::aarch64_mlxl(insn2)
&& Insn_utilities::aarch64_mem_op_p (insn1, &rt, &rt2, &pair, &load))
{
/* Any SIMD memory op is independent of the subsequent MLA
by definition of the erratum. */
if (Insn_utilities::aarch64_bit(insn1, 26))
return true;
/* If not SIMD, check for integer memory ops and MLA relationship. */
rn = Insn_utilities::aarch64_rn(insn2);
ra = Insn_utilities::aarch64_ra(insn2);
rm = Insn_utilities::aarch64_rm(insn2);
/* If this is a load and there's a true(RAW) dependency, we are safe
and this is not an erratum sequence. */
if (load &&
(rt == rn || rt == rm || rt == ra
|| (pair && (rt2 == rn || rt2 == rm || rt2 == ra))))
return false;
/* We conservatively put out stubs for all other cases (including
writebacks). */
return true;
}
return false;
}
// Helper method to create erratum stub for ST_E_843419 and ST_E_835769.
template<int size, bool big_endian>
void
Target_aarch64<size, big_endian>::create_erratum_stub(
AArch64_relobj<size, big_endian>* relobj,
unsigned int shndx,
section_size_type erratum_insn_offset,
Address erratum_address,
typename Insn_utilities::Insntype erratum_insn,
int erratum_type,
unsigned int e843419_adrp_offset)
{
gold_assert(erratum_type == ST_E_843419 || erratum_type == ST_E_835769);
The_stub_table* stub_table = relobj->stub_table(shndx);
gold_assert(stub_table != NULL);
if (stub_table->find_erratum_stub(relobj,
shndx,
erratum_insn_offset) == NULL)
{
const int BPI = AArch64_insn_utilities<big_endian>::BYTES_PER_INSN;
The_erratum_stub* stub;
if (erratum_type == ST_E_835769)
stub = new The_erratum_stub(relobj, erratum_type, shndx,
erratum_insn_offset);
else if (erratum_type == ST_E_843419)
stub = new E843419_stub<size, big_endian>(
relobj, shndx, erratum_insn_offset, e843419_adrp_offset);
else
gold_unreachable();
stub->set_erratum_insn(erratum_insn);
stub->set_erratum_address(erratum_address);
// For erratum ST_E_843419 and ST_E_835769, the destination address is
// always the next insn after erratum insn.
stub->set_destination_address(erratum_address + BPI);
stub_table->add_erratum_stub(stub);
}
}
// Scan erratum for section SHNDX range [output_address + span_start,
// output_address + span_end). Note here we do not share the code with
// scan_erratum_843419_span function, because for 843419 we optimize by only
// scanning the last few insns of a page, whereas for 835769, we need to scan
// every insn.
template<int size, bool big_endian>
void
Target_aarch64<size, big_endian>::scan_erratum_835769_span(
AArch64_relobj<size, big_endian>* relobj,
unsigned int shndx,
const section_size_type span_start,
const section_size_type span_end,
unsigned char* input_view,
Address output_address)
{
typedef typename Insn_utilities::Insntype Insntype;
const int BPI = AArch64_insn_utilities<big_endian>::BYTES_PER_INSN;
// Adjust output_address and view to the start of span.
output_address += span_start;
input_view += span_start;
section_size_type span_length = span_end - span_start;
section_size_type offset = 0;
for (offset = 0; offset + BPI < span_length; offset += BPI)
{
Insntype* ip = reinterpret_cast<Insntype*>(input_view + offset);
Insntype insn1 = ip[0];
Insntype insn2 = ip[1];
if (is_erratum_835769_sequence(insn1, insn2))
{
Insntype erratum_insn = insn2;
// "span_start + offset" is the offset for insn1. So for insn2, it is
// "span_start + offset + BPI".
section_size_type erratum_insn_offset = span_start + offset + BPI;
Address erratum_address = output_address + offset + BPI;
gold_info(_("Erratum 835769 found and fixed at \"%s\", "
"section %d, offset 0x%08x."),
relobj->name().c_str(), shndx,
(unsigned int)(span_start + offset));
this->create_erratum_stub(relobj, shndx,
erratum_insn_offset, erratum_address,
erratum_insn, ST_E_835769);
offset += BPI; // Skip mac insn.
}
}
} // End of "Target_aarch64::scan_erratum_835769_span".
// Scan erratum for section SHNDX range
// [output_address + span_start, output_address + span_end).
template<int size, bool big_endian>
void
Target_aarch64<size, big_endian>::scan_erratum_843419_span(
AArch64_relobj<size, big_endian>* relobj,
unsigned int shndx,
const section_size_type span_start,
const section_size_type span_end,
unsigned char* input_view,
Address output_address)
{
typedef typename Insn_utilities::Insntype Insntype;
// Adjust output_address and view to the start of span.
output_address += span_start;
input_view += span_start;
if ((output_address & 0x03) != 0)
return;
section_size_type offset = 0;
section_size_type span_length = span_end - span_start;
// The first instruction must be ending at 0xFF8 or 0xFFC.
unsigned int page_offset = output_address & 0xFFF;
// Make sure starting position, that is "output_address+offset",
// starts at page position 0xff8 or 0xffc.
if (page_offset < 0xff8)
offset = 0xff8 - page_offset;
while (offset + 3 * Insn_utilities::BYTES_PER_INSN <= span_length)
{
Insntype* ip = reinterpret_cast<Insntype*>(input_view + offset);
Insntype insn1 = ip[0];
if (Insn_utilities::is_adrp(insn1))
{
Insntype insn2 = ip[1];
Insntype insn3 = ip[2];
Insntype erratum_insn;
unsigned insn_offset;
bool do_report = false;
if (is_erratum_843419_sequence(insn1, insn2, insn3))
{
do_report = true;
erratum_insn = insn3;
insn_offset = 2 * Insn_utilities::BYTES_PER_INSN;
}
else if (offset + 4 * Insn_utilities::BYTES_PER_INSN <= span_length)
{
// Optionally we can have an insn between ins2 and ins3
Insntype insn_opt = ip[2];
// And insn_opt must not be a branch.
if (!Insn_utilities::aarch64_b(insn_opt)
&& !Insn_utilities::aarch64_bl(insn_opt)
&& !Insn_utilities::aarch64_blr(insn_opt)
&& !Insn_utilities::aarch64_br(insn_opt))
{
// And insn_opt must not write to dest reg in insn1. However
// we do a conservative scan, which means we may fix/report
// more than necessary, but it doesn't hurt.
Insntype insn4 = ip[3];
if (is_erratum_843419_sequence(insn1, insn2, insn4))
{
do_report = true;
erratum_insn = insn4;
insn_offset = 3 * Insn_utilities::BYTES_PER_INSN;
}
}
}
if (do_report)
{
gold_info(_("Erratum 843419 found and fixed at \"%s\", "
"section %d, offset 0x%08x."),
relobj->name().c_str(), shndx,
(unsigned int)(span_start + offset));
unsigned int erratum_insn_offset =
span_start + offset + insn_offset;
Address erratum_address =
output_address + offset + insn_offset;
create_erratum_stub(relobj, shndx,
erratum_insn_offset, erratum_address,
erratum_insn, ST_E_843419,
span_start + offset);
}
}
// Advance to next candidate instruction. We only consider instruction
// sequences starting at a page offset of 0xff8 or 0xffc.
page_offset = (output_address + offset) & 0xfff;
if (page_offset == 0xff8)
offset += 4;
else // (page_offset == 0xffc), we move to next page's 0xff8.
offset += 0xffc;
}
} // End of "Target_aarch64::scan_erratum_843419_span".
// The selector for aarch64 object files.
template<int size, bool big_endian>
class Target_selector_aarch64 : public Target_selector
{
public:
Target_selector_aarch64();
virtual Target*
do_instantiate_target()
{ return new Target_aarch64<size, big_endian>(); }
};
template<>
Target_selector_aarch64<32, true>::Target_selector_aarch64()
: Target_selector(elfcpp::EM_AARCH64, 32, true,
"elf32-bigaarch64", "aarch64_elf32_be_vec")
{ }
template<>
Target_selector_aarch64<32, false>::Target_selector_aarch64()
: Target_selector(elfcpp::EM_AARCH64, 32, false,
"elf32-littleaarch64", "aarch64_elf32_le_vec")
{ }
template<>
Target_selector_aarch64<64, true>::Target_selector_aarch64()
: Target_selector(elfcpp::EM_AARCH64, 64, true,
"elf64-bigaarch64", "aarch64_elf64_be_vec")
{ }
template<>
Target_selector_aarch64<64, false>::Target_selector_aarch64()
: Target_selector(elfcpp::EM_AARCH64, 64, false,
"elf64-littleaarch64", "aarch64_elf64_le_vec")
{ }
Target_selector_aarch64<32, true> target_selector_aarch64elf32b;
Target_selector_aarch64<32, false> target_selector_aarch64elf32;
Target_selector_aarch64<64, true> target_selector_aarch64elfb;
Target_selector_aarch64<64, false> target_selector_aarch64elf;
} // End anonymous namespace.
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