// arm.cc -- arm target support for gold.
-// Copyright (C) 2009-2014 Free Software Foundation, Inc.
+// Copyright (C) 2009-2020 Free Software Foundation, Inc.
// Written by Doug Kwan <dougkwan@google.com> based on the i386 code
// by Ian Lance Taylor <iant@google.com>.
// This file also contains borrowed and adapted code from
class Output_data_plt_arm;
template<bool big_endian>
-class Output_data_plt_arm_standard;
+class Output_data_plt_arm_short;
+
+template<bool big_endian>
+class Output_data_plt_arm_long;
template<bool big_endian>
class Stub_table;
// Target::do_select_as_default_target() hook so that we do not spend time
// building the table if we are not linking ARM objects.
//
-// An alternative is to to process the information in arm-reloc.def in
+// An alternative is to process the information in arm-reloc.def in
// compilation time and generate a representation of it in PODs only. That
// way we can avoid initialization when the linker starts.
// Name of key. This is mainly for debugging.
std::string
- name() const;
+ name() const ATTRIBUTE_UNUSED;
private:
// Stub type.
// bits. The default handling of relocatable relocation cannot process these
// relocations. So we have to extend the default code.
-template<bool big_endian, int sh_type, typename Classify_reloc>
+template<bool big_endian, typename Classify_reloc>
class Arm_scan_relocatable_relocs :
- public Default_scan_relocatable_relocs<sh_type, Classify_reloc>
+ public Default_scan_relocatable_relocs<Classify_reloc>
{
public:
// Return the strategy to use for a local symbol which is a section
inline Relocatable_relocs::Reloc_strategy
local_section_strategy(unsigned int r_type, Relobj*)
{
- if (sh_type == elfcpp::SHT_RELA)
+ if (Classify_reloc::sh_type == elfcpp::SHT_RELA)
return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_RELA;
else
{
Target_arm(const Target::Target_info* info = &arm_info)
: Sized_target<32, big_endian>(info),
- got_(NULL), plt_(NULL), got_plt_(NULL), rel_dyn_(NULL),
- copy_relocs_(elfcpp::R_ARM_COPY),
+ got_(NULL), plt_(NULL), got_plt_(NULL), got_irelative_(NULL),
+ rel_dyn_(NULL), rel_irelative_(NULL), copy_relocs_(elfcpp::R_ARM_COPY),
got_mod_index_offset_(-1U), tls_base_symbol_defined_(false),
stub_tables_(), stub_factory_(Stub_factory::get_instance()),
should_force_pic_veneer_(false),
arm_input_section_map_(), attributes_section_data_(NULL),
- fix_cortex_a8_(false), cortex_a8_relocs_info_()
+ fix_cortex_a8_(false), cortex_a8_relocs_info_(),
+ target1_reloc_(elfcpp::R_ARM_ABS32),
+ // This can be any reloc type but usually is R_ARM_GOT_PREL.
+ target2_reloc_(elfcpp::R_ARM_GOT_PREL)
{ }
// Whether we force PCI branch veneers.
uint64_t
do_dynsym_value(const Symbol*) const;
+ // Return the plt address for globals. Since we have irelative plt entries,
+ // address calculation is not as straightforward as plt_address + plt_offset.
+ uint64_t
+ do_plt_address_for_global(const Symbol* gsym) const
+ { return this->plt_section()->address_for_global(gsym); }
+
+ // Return the plt address for locals. Since we have irelative plt entries,
+ // address calculation is not as straightforward as plt_address + plt_offset.
+ uint64_t
+ do_plt_address_for_local(const Relobj* relobj, unsigned int symndx) const
+ { return this->plt_section()->address_for_local(relobj, symndx); }
+
// Relocate a section.
void
relocate_section(const Relocate_info<32, big_endian>*,
const unsigned char* plocal_symbols,
Relocatable_relocs*);
+ // Scan the relocs for --emit-relocs.
+ void
+ emit_relocs_scan(Symbol_table* symtab,
+ Layout* layout,
+ Sized_relobj_file<32, 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_syms,
+ Relocatable_relocs* rr);
+
// Emit relocations for a section.
void
relocate_relocs(const Relocate_info<32, big_endian>*,
Output_section* output_section,
typename elfcpp::Elf_types<32>::Elf_Off
offset_in_output_section,
- const Relocatable_relocs*,
unsigned char* view,
Arm_address view_address,
section_size_type view_size,
unsigned int
plt_entry_size() const;
+ // Get the section to use for IRELATIVE relocations, create it if necessary.
+ Reloc_section*
+ rel_irelative_section(Layout*);
+
// Map platform-specific reloc types
- static unsigned int
- get_real_reloc_type(unsigned int r_type);
+ unsigned int
+ get_real_reloc_type(unsigned int r_type) const;
//
// Methods to support stub-generations.
protected:
// Make the PLT-generator object.
Output_data_plt_arm<big_endian>*
- make_data_plt(Layout* layout, Output_data_space* got_plt)
- { return this->do_make_data_plt(layout, got_plt); }
+ make_data_plt(Layout* layout,
+ Arm_output_data_got<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); }
// Make an ELF object.
Object*
// as the default.
gold_assert(arm_reloc_property_table == NULL);
arm_reloc_property_table = new Arm_reloc_property_table();
+ if (parameters->options().user_set_target1_rel())
+ {
+ // FIXME: This is not strictly compatible with ld, which allows both
+ // --target1-abs and --target-rel to be given.
+ if (parameters->options().user_set_target1_abs())
+ gold_error(_("Cannot use both --target1-abs and --target1-rel."));
+ else
+ this->target1_reloc_ = elfcpp::R_ARM_REL32;
+ }
+ // We don't need to handle --target1-abs because target1_reloc_ is set
+ // to elfcpp::R_ARM_ABS32 in the member initializer list.
+
+ if (parameters->options().user_set_target2())
+ {
+ const char* target2 = parameters->options().target2();
+ if (strcmp(target2, "rel") == 0)
+ this->target2_reloc_ = elfcpp::R_ARM_REL32;
+ else if (strcmp(target2, "abs") == 0)
+ this->target2_reloc_ = elfcpp::R_ARM_ABS32;
+ else if (strcmp(target2, "got-rel") == 0)
+ this->target2_reloc_ = elfcpp::R_ARM_GOT_PREL;
+ else
+ gold_unreachable();
+ }
}
// Virtual function which is set to return true by a target if
do_define_standard_symbols(Symbol_table*, Layout*);
virtual Output_data_plt_arm<big_endian>*
- do_make_data_plt(Layout* layout, Output_data_space* got_plt)
+ do_make_data_plt(Layout* layout,
+ Arm_output_data_got<big_endian>* got,
+ Output_data_space* got_plt,
+ Output_data_space* got_irelative)
{
- return new Output_data_plt_arm_standard<big_endian>(layout, got_plt);
+ gold_assert(got_plt != NULL && got_irelative != NULL);
+ if (parameters->options().long_plt())
+ return new Output_data_plt_arm_long<big_endian>(
+ layout, got, got_plt, got_irelative);
+ else
+ return new Output_data_plt_arm_short<big_endian>(
+ layout, got, got_plt, got_irelative);
}
private:
if (sym->is_undefined() && !parameters->options().shared())
return false;
+ if (sym->type() == elfcpp::STT_GNU_IFUNC)
+ return true;
+
return (!parameters->doing_static_link()
&& (sym->type() == elfcpp::STT_FUNC
|| sym->type() == elfcpp::STT_ARM_TFUNC)
inline bool
possible_function_pointer_reloc(unsigned int r_type);
+ // Whether a plt entry is needed for ifunc.
+ bool
+ reloc_needs_plt_for_ifunc(Sized_relobj_file<32, big_endian>*,
+ unsigned int r_type);
+
// Whether we have issued an error about a non-PIC compilation.
bool issued_non_pic_error_;
};
// Do a relocation. Return false if the caller should not issue
// any warnings about this relocation.
inline bool
- relocate(const Relocate_info<32, big_endian>*, Target_arm*,
- Output_section*, size_t relnum,
- const elfcpp::Rel<32, big_endian>&,
- unsigned int r_type, const Sized_symbol<32>*,
- const Symbol_value<32>*,
- unsigned char*, Arm_address,
- section_size_type);
+ relocate(const Relocate_info<32, big_endian>*, unsigned int,
+ Target_arm*, Output_section*, size_t, const unsigned char*,
+ const Sized_symbol<32>*, const Symbol_value<32>*,
+ unsigned char*, Arm_address, section_size_type);
// Return whether we want to pass flag NON_PIC_REF for this
// reloc. This means the relocation type accesses a symbol not via
};
- // A class which returns the size required for a relocation type,
- // used while scanning relocs during a relocatable link.
- class Relocatable_size_for_reloc
+ // A class for inquiring about properties of a relocation,
+ // used while scanning relocs during a relocatable link and
+ // garbage collection.
+ class Classify_reloc :
+ public gold::Default_classify_reloc<elfcpp::SHT_REL, 32, big_endian>
{
public:
- unsigned int
+ typedef typename Reloc_types<elfcpp::SHT_REL, 32, big_endian>::Reloc
+ Reltype;
+
+ // Return the explicit addend of the relocation (return 0 for SHT_REL).
+ static typename elfcpp::Elf_types<32>::Elf_Swxword
+ get_r_addend(const Reltype*)
+ { return 0; }
+
+ // Return the size of the addend of the relocation (only used for SHT_REL).
+ static unsigned int
get_size_for_reloc(unsigned int, Relobj*);
};
return this->got_plt_;
}
+ // 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<32, 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*);
unsigned int shndx, Output_section* output_section,
Symbol* sym, const elfcpp::Rel<32, big_endian>& reloc)
{
+ unsigned int r_type = elfcpp::elf_r_type<32>(reloc.get_r_info());
this->copy_relocs_.copy_reloc(symtab, layout,
symtab->get_sized_symbol<32>(sym),
- object, shndx, output_section, reloc,
+ object, shndx, output_section,
+ r_type, reloc.get_r_offset(), 0,
this->rel_dyn_section(layout));
}
Output_data_plt_arm<big_endian>* plt_;
// The GOT PLT section.
Output_data_space* got_plt_;
+ // The GOT section for IRELATIVE relocations.
+ Output_data_space* got_irelative_;
// The dynamic reloc section.
Reloc_section* rel_dyn_;
+ // The section to use for IRELATIVE relocs.
+ Reloc_section* rel_irelative_;
// Relocs saved to avoid a COPY reloc.
Copy_relocs<elfcpp::SHT_REL, 32, big_endian> copy_relocs_;
// Offset of the GOT entry for the TLS module index.
bool fix_cortex_a8_;
// Map addresses to relocs for Cortex-A8 erratum.
Cortex_a8_relocs_info cortex_a8_relocs_info_;
+ // What R_ARM_TARGET1 maps to. It can be R_ARM_REL32 or R_ARM_ABS32.
+ unsigned int target1_reloc_;
+ // What R_ARM_TARGET2 maps to. It should be one of R_ARM_REL32, R_ARM_ABS32
+ // and R_ARM_GOT_PREL.
+ unsigned int target2_reloc_;
};
template<bool big_endian>
0, // large_common_section_flags
".ARM.attributes", // attributes_section
"aeabi", // attributes_vendor
- "_start" // entry_symbol_name
+ "_start", // entry_symbol_name
+ 32, // hash_entry_size
+ elfcpp::SHT_PROGBITS, // unwind_section_type
};
// Arm relocate functions class
const Symbol_value<32>* psymval, Arm_address address,
Arm_address thumb_bit);
- // R_ARM_THM_JUMP6: S + A – P
+ // R_ARM_THM_JUMP6: S + A - P
static inline typename This::Status
thm_jump6(unsigned char* view,
const Sized_relobj_file<32, big_endian>* object,
typedef typename elfcpp::Swap<16, big_endian>::Valtype Reltype;
Valtype* wv = reinterpret_cast<Valtype*>(view);
Valtype val = elfcpp::Swap<16, big_endian>::readval(wv);
- // bit[9]:bit[7:3]:’0’ (mask: 0x02f8)
+ // bit[9]:bit[7:3]:'0' (mask: 0x02f8)
Reltype addend = (((val & 0x0200) >> 3) | ((val & 0x00f8) >> 2));
Reltype x = (psymval->value(object, addend) - address);
val = (val & 0xfd07) | ((x & 0x0040) << 3) | ((val & 0x003e) << 2);
: This::STATUS_OKAY);
}
- // R_ARM_THM_JUMP8: S + A – P
+ // R_ARM_THM_JUMP8: S + A - P
static inline typename This::Status
thm_jump8(unsigned char* view,
const Sized_relobj_file<32, big_endian>* object,
: This::STATUS_OKAY);
}
- // R_ARM_THM_JUMP11: S + A – P
+ // R_ARM_THM_JUMP11: S + A - P
static inline typename This::Status
thm_jump11(unsigned char* view,
const Sized_relobj_file<32, big_endian>* object,
elfcpp::STB_LOCAL,
elfcpp::STV_HIDDEN, 0,
false, false);
+
+ // 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(4, "** GOT IRELATIVE PLT");
+ layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS,
+ (elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE),
+ this->got_irelative_,
+ got_order, is_got_relro);
+
}
return this->got_;
}
if (this->rel_dyn_ == NULL)
{
gold_assert(layout != NULL);
+ // Create both relocation sections in the same place, so as to ensure
+ // their relative order in the output section.
this->rel_dyn_ = new Reloc_section(parameters->options().combreloc());
+ this->rel_irelative_ = new Reloc_section(false);
layout->add_output_section_data(".rel.dyn", elfcpp::SHT_REL,
elfcpp::SHF_ALLOC, this->rel_dyn_,
ORDER_DYNAMIC_RELOCS, false);
+ layout->add_output_section_data(".rel.dyn", elfcpp::SHT_REL,
+ elfcpp::SHF_ALLOC, this->rel_irelative_,
+ ORDER_DYNAMIC_RELOCS, false);
}
return this->rel_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<bool big_endian>
+typename Target_arm<big_endian>::Reloc_section*
+Target_arm<big_endian>::rel_irelative_section(Layout* layout)
+{
+ if (this->rel_irelative_ == NULL)
+ {
+ // Delegate the creation to rel_dyn_section so as to ensure their order in
+ // the output section.
+ this->rel_dyn_section(layout);
+ gold_assert(this->rel_irelative_ != NULL
+ && (this->rel_dyn_->output_section()
+ == this->rel_irelative_->output_section()));
+ }
+ return this->rel_irelative_;
+}
+
+
// Insn_template methods.
// Return byte size of an instruction template.
{
const Stub_template* stub_template = this->stub_template();
const Insn_template* insns = stub_template->insns();
+ const bool enable_be8 = parameters->options().be8();
- // FIXME: We do not handle BE8 encoding yet.
unsigned char* pov = view;
for (size_t i = 0; i < stub_template->insn_count(); i++)
{
switch (insns[i].type())
{
case Insn_template::THUMB16_TYPE:
- elfcpp::Swap<16, big_endian>::writeval(pov, insns[i].data() & 0xffff);
+ if (enable_be8)
+ elfcpp::Swap<16, false>::writeval(pov, insns[i].data() & 0xffff);
+ else
+ elfcpp::Swap<16, big_endian>::writeval(pov,
+ insns[i].data() & 0xffff);
break;
case Insn_template::THUMB16_SPECIAL_TYPE:
- elfcpp::Swap<16, big_endian>::writeval(
- pov,
- this->thumb16_special(i));
+ if (enable_be8)
+ elfcpp::Swap<16, false>::writeval(pov, this->thumb16_special(i));
+ else
+ elfcpp::Swap<16, big_endian>::writeval(pov,
+ this->thumb16_special(i));
break;
case Insn_template::THUMB32_TYPE:
{
uint32_t hi = (insns[i].data() >> 16) & 0xffff;
uint32_t lo = insns[i].data() & 0xffff;
- elfcpp::Swap<16, big_endian>::writeval(pov, hi);
- elfcpp::Swap<16, big_endian>::writeval(pov + 2, lo);
+ if (enable_be8)
+ {
+ elfcpp::Swap<16, false>::writeval(pov, hi);
+ elfcpp::Swap<16, false>::writeval(pov + 2, lo);
+ }
+ else
+ {
+ elfcpp::Swap<16, big_endian>::writeval(pov, hi);
+ elfcpp::Swap<16, big_endian>::writeval(pov + 2, lo);
+ }
}
break;
case Insn_template::ARM_TYPE:
+ if (enable_be8)
+ elfcpp::Swap<32, false>::writeval(pov, insns[i].data());
+ else
+ elfcpp::Swap<32, big_endian>::writeval(pov, insns[i].data());
+ break;
case Insn_template::DATA_TYPE:
elfcpp::Swap<32, big_endian>::writeval(pov, insns[i].data());
break;
// This is a bit ugly but we want to avoid using a templated class for
// big and little endianities.
bool may_use_blx;
- bool should_force_pic_veneer;
+ bool should_force_pic_veneer = parameters->options().pic_veneer();
bool thumb2;
bool thumb_only;
if (parameters->target().is_big_endian())
const Target_arm<true>* big_endian_target =
Target_arm<true>::default_target();
may_use_blx = big_endian_target->may_use_v5t_interworking();
- should_force_pic_veneer = big_endian_target->should_force_pic_veneer();
+ should_force_pic_veneer |= big_endian_target->should_force_pic_veneer();
thumb2 = big_endian_target->using_thumb2();
thumb_only = big_endian_target->using_thumb_only();
}
const Target_arm<false>* little_endian_target =
Target_arm<false>::default_target();
may_use_blx = little_endian_target->may_use_v5t_interworking();
- should_force_pic_veneer = little_endian_target->should_force_pic_veneer();
+ should_force_pic_veneer |=
+ little_endian_target->should_force_pic_veneer();
thumb2 = little_endian_target->using_thumb2();
thumb_only = little_endian_target->using_thumb_only();
}
this->mapping_symbols_info_.lower_bound(section_start);
// There are no mapping symbols for this section. Treat it as a data-only
- // section. Issue a warning if section is marked as containing
- // instructions.
+ // section.
if (p == this->mapping_symbols_info_.end() || p->first.first != shndx)
- {
- if ((this->section_flags(shndx) & elfcpp::SHF_EXECINSTR) != 0)
- gold_warning(_("cannot scan executable section %u of %s for Cortex-A8 "
- "erratum because it has no mapping symbols."),
- shndx, this->name().c_str());
- return;
- }
+ return;
Arm_address output_address =
this->simple_input_section_output_address(shndx, os);
Output_file* of,
typename Sized_relobj_file<32, big_endian>::Views* pviews)
{
- // Call parent to relocate sections.
- Sized_relobj_file<32, big_endian>::do_relocate_sections(symtab, layout,
- pshdrs, of, pviews);
+ // Relocate the section data.
+ this->relocate_section_range(symtab, layout, pshdrs, of, pviews,
+ 1, this->shnum() - 1);
// We do not generate stubs if doing a relocatable link.
if (parameters->options().relocatable())
section_address,
section_size);
}
+ // BE8 swapping
+ if (parameters->options().be8())
+ {
+ section_size_type span_start, span_end;
+ elfcpp::Shdr<32, big_endian>
+ shdr(pshdrs + i * elfcpp::Elf_sizes<32>::shdr_size);
+ Mapping_symbol_position section_start(i, 0);
+ typename Mapping_symbols_info::const_iterator p =
+ this->mapping_symbols_info_.lower_bound(section_start);
+ unsigned char* view = (*pviews)[i].view;
+ Arm_address view_address = (*pviews)[i].address;
+ section_size_type view_size = (*pviews)[i].view_size;
+ while (p != this->mapping_symbols_info_.end()
+ && p->first.first == i)
+ {
+ typename Mapping_symbols_info::const_iterator next =
+ this->mapping_symbols_info_.upper_bound(p->first);
+
+ // Only swap arm or thumb code.
+ if ((p->second == 'a') || (p->second == 't'))
+ {
+ Output_section* os = this->output_section(i);
+ gold_assert(os != NULL);
+ Arm_address section_address =
+ this->simple_input_section_output_address(i, os);
+ span_start = convert_to_section_size_type(p->first.second);
+ if (next != this->mapping_symbols_info_.end()
+ && next->first.first == i)
+ span_end =
+ convert_to_section_size_type(next->first.second);
+ else
+ span_end =
+ convert_to_section_size_type(shdr.get_sh_size());
+ unsigned char* section_view =
+ view + (section_address - view_address);
+ uint64_t section_size = this->section_size(i);
+
+ gold_assert(section_address >= view_address
+ && ((section_address + section_size)
+ <= (view_address + view_size)));
+
+ // Set Output view for swapping
+ unsigned char *oview = section_view + span_start;
+ unsigned int index = 0;
+ if (p->second == 'a')
+ {
+ while (index + 3 < (span_end - span_start))
+ {
+ typedef typename elfcpp::Swap<32, big_endian>
+ ::Valtype Valtype;
+ Valtype* wv =
+ reinterpret_cast<Valtype*>(oview+index);
+ uint32_t val = elfcpp::Swap<32, false>::readval(wv);
+ elfcpp::Swap<32, true>::writeval(wv, val);
+ index += 4;
+ }
+ }
+ else if (p->second == 't')
+ {
+ while (index + 1 < (span_end - span_start))
+ {
+ typedef typename elfcpp::Swap<16, big_endian>
+ ::Valtype Valtype;
+ Valtype* wv =
+ reinterpret_cast<Valtype*>(oview+index);
+ uint16_t val = elfcpp::Swap<16, false>::readval(wv);
+ elfcpp::Swap<16, true>::writeval(wv, val);
+ index += 2;
+ }
+ }
+ }
+ p = next;
+ }
+ }
}
}
class Output_data_plt_arm : public Output_section_data
{
public:
+ // Unlike aarch64, which records symbol value in "addend" field of relocations
+ // and could be done at the same time an IRelative reloc is created for the
+ // symbol, arm puts the symbol value into "GOT" table, which, however, is
+ // issued later in Output_data_plt_arm::do_write(). So we have a struct here
+ // to keep necessary symbol information for later use in do_write. We usually
+ // have only a very limited number of ifuncs, so the extra data required here
+ // is also limited.
+
+ struct IRelative_data
+ {
+ IRelative_data(Sized_symbol<32>* sized_symbol)
+ : symbol_is_global_(true)
+ {
+ u_.global = sized_symbol;
+ }
+
+ IRelative_data(Sized_relobj_file<32, big_endian>* relobj,
+ unsigned int index)
+ : symbol_is_global_(false)
+ {
+ u_.local.relobj = relobj;
+ u_.local.index = index;
+ }
+
+ union
+ {
+ Sized_symbol<32>* global;
+
+ struct
+ {
+ Sized_relobj_file<32, big_endian>* relobj;
+ unsigned int index;
+ } local;
+ } u_;
+
+ bool symbol_is_global_;
+ };
+
typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, big_endian>
Reloc_section;
- Output_data_plt_arm(Layout*, uint64_t addralign, Output_data_space*);
+ Output_data_plt_arm(Layout* layout, uint64_t addralign,
+ Arm_output_data_got<big_endian>* got,
+ Output_data_space* got_plt,
+ Output_data_space* got_irelative);
// Add an entry to the PLT.
void
- add_entry(Symbol* gsym);
+ add_entry(Symbol_table* symtab, Layout* layout, Symbol* gsym);
+
+ // Add the relocation for a plt entry.
+ void
+ add_relocation(Symbol_table* symtab, Layout* layout,
+ Symbol* gsym, unsigned int got_offset);
+
+ // 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<32, big_endian>* relobj,
+ unsigned int local_sym_index);
// Return the .rel.plt section data.
const Reloc_section*
rel_plt() const
{ return this->rel_; }
+ // Return the PLT relocation container for IRELATIVE.
+ Reloc_section*
+ rel_irelative(Symbol_table*, Layout*);
+
// Return the number of PLT entries.
unsigned int
entry_count() const
- { return this->count_; }
+ { return this->count_ + this->irelative_count_; }
// Return the offset of the first non-reserved PLT entry.
unsigned int
get_plt_entry_size() const
{ return this->do_get_plt_entry_size(); }
+ // Return the PLT address for globals.
+ uint32_t
+ address_for_global(const Symbol*) const;
+
+ // Return the PLT address for locals.
+ uint32_t
+ address_for_local(const Relobj*, unsigned int symndx) const;
+
protected:
// Fill in the first PLT entry.
void
set_final_data_size()
{
this->set_data_size(this->first_plt_entry_offset()
- + this->count_ * this->get_plt_entry_size());
+ + ((this->count_ + this->irelative_count_)
+ * this->get_plt_entry_size()));
}
// Write out the PLT data.
void
do_write(Output_file*);
+ // Record irelative symbol data.
+ void insert_irelative_data(const IRelative_data& idata)
+ { irelative_data_vec_.push_back(idata); }
+
// The reloc section.
Reloc_section* rel_;
+ // The IRELATIVE relocs, if necessary. These must follow the
+ // regular PLT relocations.
+ Reloc_section* irelative_rel_;
+ // The .got section.
+ Arm_output_data_got<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_ARM_IRELATIVE relocs. These
+ // follow the regular PLT entries.
+ unsigned int irelative_count_;
+ // Vector for irelative data.
+ typedef std::vector<IRelative_data> IRelative_data_vec;
+ IRelative_data_vec irelative_data_vec_;
};
// Create the PLT section. The ordinary .got section is an argument,
// section just for PLT entries.
template<bool big_endian>
-Output_data_plt_arm<big_endian>::Output_data_plt_arm(Layout* layout,
- uint64_t addralign,
- Output_data_space* got_plt)
- : Output_section_data(addralign), got_plt_(got_plt), count_(0)
+Output_data_plt_arm<big_endian>::Output_data_plt_arm(
+ Layout* layout, uint64_t addralign,
+ Arm_output_data_got<big_endian>* got,
+ Output_data_space* got_plt,
+ Output_data_space* got_irelative)
+ : Output_section_data(addralign), irelative_rel_(NULL),
+ got_(got), got_plt_(got_plt), got_irelative_(got_irelative),
+ count_(0), irelative_count_(0)
{
this->rel_ = new Reloc_section(false);
layout->add_output_section_data(".rel.plt", elfcpp::SHT_REL,
template<bool big_endian>
void
-Output_data_plt_arm<big_endian>::add_entry(Symbol* gsym)
+Output_data_plt_arm<big_endian>::add_entry(Symbol_table* symtab,
+ Layout* layout,
+ Symbol* gsym)
{
gold_assert(!gsym->has_plt_offset());
- // Note that when setting the PLT offset we skip the initial
- // reserved PLT entry.
- gsym->set_plt_offset((this->count_) * this->get_plt_entry_size()
- + this->first_plt_entry_offset());
+ unsigned int* entry_count;
+ Output_section_data_build* got;
+
+ // We have 2 different types of plt entry here, normal and ifunc.
+
+ // For normal plt, the offset begins with first_plt_entry_offset(20), and the
+ // 1st entry offset would be 20, the second 32, third 44 ... etc.
- ++this->count_;
+ // For ifunc plt, the offset begins with 0. So the first offset would 0,
+ // second 12, third 24 ... etc.
- section_offset_type got_offset = this->got_plt_->current_data_size();
+ // IFunc plt entries *always* come after *normal* plt entries.
+
+ // Notice, when computing the plt address of a certain symbol, "plt_address +
+ // plt_offset" is no longer correct. Use target->plt_address_for_global() or
+ // target->plt_address_for_local() instead.
+
+ int begin_offset = 0;
+ if (gsym->type() == elfcpp::STT_GNU_IFUNC
+ && gsym->can_use_relative_reloc(false))
+ {
+ entry_count = &this->irelative_count_;
+ got = this->got_irelative_;
+ // For irelative plt entries, offset is relative to the end of normal plt
+ // entries, so it starts from 0.
+ begin_offset = 0;
+ // Record symbol information.
+ this->insert_irelative_data(
+ IRelative_data(symtab->get_sized_symbol<32>(gsym)));
+ }
+ else
+ {
+ entry_count = &this->count_;
+ got = this->got_plt_;
+ // Note that for normal plt entries, when setting the PLT offset we skip
+ // the initial reserved PLT entry.
+ begin_offset = this->first_plt_entry_offset();
+ }
+
+ gsym->set_plt_offset(begin_offset
+ + (*entry_count) * this->get_plt_entry_size());
+
+ ++(*entry_count);
+
+ 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).
- this->got_plt_->set_current_data_size(got_offset + 4);
+ got->set_current_data_size(got_offset + 4);
// Every PLT entry needs a reloc.
- gsym->set_needs_dynsym_entry();
- this->rel_->add_global(gsym, elfcpp::R_ARM_JUMP_SLOT, this->got_plt_,
- got_offset);
+ 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<bool big_endian>
+unsigned int
+Output_data_plt_arm<big_endian>::add_local_ifunc_entry(
+ Symbol_table* symtab,
+ Layout* layout,
+ Sized_relobj_file<32, big_endian>* relobj,
+ unsigned int local_sym_index)
+{
+ this->insert_irelative_data(IRelative_data(relobj, local_sym_index));
+
+ // Notice, when computingthe plt entry address, "plt_address + plt_offset" is
+ // no longer correct. Use target->plt_address_for_local() instead.
+ 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 + 4);
+
+
+ // Every PLT entry needs a reloc.
+ Reloc_section* rel = this->rel_irelative(symtab, layout);
+ rel->add_symbolless_local_addend(relobj, local_sym_index,
+ elfcpp::R_ARM_IRELATIVE,
+ this->got_irelative_, got_offset);
+ return plt_offset;
+}
+
+
+// Add the relocation for a PLT entry.
+
+template<bool big_endian>
+void
+Output_data_plt_arm<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* rel = this->rel_irelative(symtab, layout);
+ rel->add_symbolless_global_addend(gsym, elfcpp::R_ARM_IRELATIVE,
+ this->got_irelative_, got_offset);
+ }
+ else
+ {
+ gsym->set_needs_dynsym_entry();
+ this->rel_->add_global(gsym, elfcpp::R_ARM_JUMP_SLOT, this->got_plt_,
+ got_offset);
+ }
+}
+
+
+// Create the irelative relocation data.
+
+template<bool big_endian>
+typename Output_data_plt_arm<big_endian>::Reloc_section*
+Output_data_plt_arm<big_endian>::rel_irelative(Symbol_table* symtab,
+ Layout* layout)
+{
+ if (this->irelative_rel_ == NULL)
+ {
+ // Since irelative relocations goes into 'rel.dyn', we delegate the
+ // creation of irelative_rel_ to where rel_dyn section gets created.
+ Target_arm<big_endian>* arm_target =
+ Target_arm<big_endian>::default_target();
+ this->irelative_rel_ = arm_target->rel_irelative_section(layout);
+
+ // Make sure we have a place for the TLSDESC relocations, in
+ // case we see any later on.
+ // this->rel_tlsdesc(layout);
+ if (parameters->doing_static_link())
+ {
+ // A statically linked executable will only have a .rel.plt section to
+ // hold R_ARM_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("__rel_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("__rel_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 for a global symbol.
+
+template<bool big_endian>
+uint32_t
+Output_data_plt_arm<big_endian>::address_for_global(const Symbol* gsym) const
+{
+ uint64_t begin_offset = 0;
+ if (gsym->type() == elfcpp::STT_GNU_IFUNC
+ && gsym->can_use_relative_reloc(false))
+ {
+ begin_offset = (this->first_plt_entry_offset() +
+ this->count_ * this->get_plt_entry_size());
+ }
+ return this->address() + begin_offset + gsym->plt_offset();
+}
+
+
+// Return the PLT address for a local symbol. These are always
+// IRELATIVE relocs.
+
+template<bool big_endian>
+uint32_t
+Output_data_plt_arm<big_endian>::address_for_local(
+ const Relobj* object,
+ unsigned int r_sym) const
+{
+ return (this->address()
+ + this->first_plt_entry_offset()
+ + this->count_ * this->get_plt_entry_size()
+ + object->local_plt_offset(r_sym));
+}
+
+
template<bool big_endian>
class Output_data_plt_arm_standard : public Output_data_plt_arm<big_endian>
{
public:
- Output_data_plt_arm_standard(Layout* layout, Output_data_space* got_plt)
- : Output_data_plt_arm<big_endian>(layout, 4, got_plt)
+ Output_data_plt_arm_standard(Layout* layout,
+ Arm_output_data_got<big_endian>* got,
+ Output_data_space* got_plt,
+ Output_data_space* got_irelative)
+ : Output_data_plt_arm<big_endian>(layout, 4, got, got_plt, got_irelative)
{ }
protected:
do_first_plt_entry_offset() const
{ return sizeof(first_plt_entry); }
- // Return the size of a PLT entry.
- virtual unsigned int
- do_get_plt_entry_size() const
- { return sizeof(plt_entry); }
-
virtual void
do_fill_first_plt_entry(unsigned char* pov,
Arm_address got_address,
Arm_address plt_address);
- virtual void
- do_fill_plt_entry(unsigned char* pov,
- Arm_address got_address,
- Arm_address plt_address,
- unsigned int got_offset,
- unsigned int plt_offset);
-
private:
// Template for the first PLT entry.
static const uint32_t first_plt_entry[5];
-
- // Template for subsequent PLT entries.
- static const uint32_t plt_entry[3];
};
// ARM PLTs.
{
// Write first PLT entry. All but the last word are constants.
const size_t num_first_plt_words = (sizeof(first_plt_entry)
- / sizeof(plt_entry[0]));
+ / sizeof(first_plt_entry[0]));
for (size_t i = 0; i < num_first_plt_words - 1; i++)
- elfcpp::Swap<32, big_endian>::writeval(pov + i * 4, first_plt_entry[i]);
+ {
+ if (parameters->options().be8())
+ {
+ elfcpp::Swap<32, false>::writeval(pov + i * 4,
+ first_plt_entry[i]);
+ }
+ else
+ {
+ elfcpp::Swap<32, big_endian>::writeval(pov + i * 4,
+ first_plt_entry[i]);
+ }
+ }
// Last word in first PLT entry is &GOT[0] - .
elfcpp::Swap<32, big_endian>::writeval(pov + 16,
got_address - (plt_address + 16));
}
// Subsequent entries in the PLT.
+// This class generates short (12-byte) entries, for displacements up to 2^28.
+
+template<bool big_endian>
+class Output_data_plt_arm_short : public Output_data_plt_arm_standard<big_endian>
+{
+ public:
+ Output_data_plt_arm_short(Layout* layout,
+ Arm_output_data_got<big_endian>* got,
+ Output_data_space* got_plt,
+ Output_data_space* got_irelative)
+ : Output_data_plt_arm_standard<big_endian>(layout, got, got_plt, got_irelative)
+ { }
+
+ protected:
+ // Return the size of a PLT entry.
+ virtual unsigned int
+ do_get_plt_entry_size() const
+ { return sizeof(plt_entry); }
+
+ virtual void
+ do_fill_plt_entry(unsigned char* pov,
+ Arm_address got_address,
+ Arm_address plt_address,
+ unsigned int got_offset,
+ unsigned int plt_offset);
+
+ private:
+ // Template for subsequent PLT entries.
+ static const uint32_t plt_entry[3];
+};
template<bool big_endian>
-const uint32_t Output_data_plt_arm_standard<big_endian>::plt_entry[3] =
+const uint32_t Output_data_plt_arm_short<big_endian>::plt_entry[3] =
{
0xe28fc600, // add ip, pc, #0xNN00000
0xe28cca00, // add ip, ip, #0xNN000
template<bool big_endian>
void
-Output_data_plt_arm_standard<big_endian>::do_fill_plt_entry(
+Output_data_plt_arm_short<big_endian>::do_fill_plt_entry(
unsigned char* pov,
Arm_address got_address,
Arm_address plt_address,
{
int32_t offset = ((got_address + got_offset)
- (plt_address + plt_offset + 8));
+ if (offset < 0 || offset > 0x0fffffff)
+ gold_error(_("PLT offset too large, try linking with --long-plt"));
- gold_assert(offset >= 0 && offset < 0x0fffffff);
uint32_t plt_insn0 = plt_entry[0] | ((offset >> 20) & 0xff);
- elfcpp::Swap<32, big_endian>::writeval(pov, plt_insn0);
uint32_t plt_insn1 = plt_entry[1] | ((offset >> 12) & 0xff);
- elfcpp::Swap<32, big_endian>::writeval(pov + 4, plt_insn1);
uint32_t plt_insn2 = plt_entry[2] | (offset & 0xfff);
- elfcpp::Swap<32, big_endian>::writeval(pov + 8, plt_insn2);
+
+ if (parameters->options().be8())
+ {
+ elfcpp::Swap<32, false>::writeval(pov, plt_insn0);
+ elfcpp::Swap<32, false>::writeval(pov + 4, plt_insn1);
+ elfcpp::Swap<32, false>::writeval(pov + 8, plt_insn2);
+ }
+ else
+ {
+ elfcpp::Swap<32, big_endian>::writeval(pov, plt_insn0);
+ elfcpp::Swap<32, big_endian>::writeval(pov + 4, plt_insn1);
+ elfcpp::Swap<32, big_endian>::writeval(pov + 8, plt_insn2);
+ }
+}
+
+// This class generates long (16-byte) entries, for arbitrary displacements.
+
+template<bool big_endian>
+class Output_data_plt_arm_long : public Output_data_plt_arm_standard<big_endian>
+{
+ public:
+ Output_data_plt_arm_long(Layout* layout,
+ Arm_output_data_got<big_endian>* got,
+ Output_data_space* got_plt,
+ Output_data_space* got_irelative)
+ : Output_data_plt_arm_standard<big_endian>(layout, got, got_plt, got_irelative)
+ { }
+
+ protected:
+ // Return the size of a PLT entry.
+ virtual unsigned int
+ do_get_plt_entry_size() const
+ { return sizeof(plt_entry); }
+
+ virtual void
+ do_fill_plt_entry(unsigned char* pov,
+ Arm_address got_address,
+ Arm_address plt_address,
+ unsigned int got_offset,
+ unsigned int plt_offset);
+
+ private:
+ // Template for subsequent PLT entries.
+ static const uint32_t plt_entry[4];
+};
+
+template<bool big_endian>
+const uint32_t Output_data_plt_arm_long<big_endian>::plt_entry[4] =
+{
+ 0xe28fc200, // add ip, pc, #0xN0000000
+ 0xe28cc600, // add ip, ip, #0xNN00000
+ 0xe28cca00, // add ip, ip, #0xNN000
+ 0xe5bcf000, // ldr pc, [ip, #0xNNN]!
+};
+
+template<bool big_endian>
+void
+Output_data_plt_arm_long<big_endian>::do_fill_plt_entry(
+ unsigned char* pov,
+ Arm_address got_address,
+ Arm_address plt_address,
+ unsigned int got_offset,
+ unsigned int plt_offset)
+{
+ int32_t offset = ((got_address + got_offset)
+ - (plt_address + plt_offset + 8));
+
+ uint32_t plt_insn0 = plt_entry[0] | (offset >> 28);
+ uint32_t plt_insn1 = plt_entry[1] | ((offset >> 20) & 0xff);
+ uint32_t plt_insn2 = plt_entry[2] | ((offset >> 12) & 0xff);
+ uint32_t plt_insn3 = plt_entry[3] | (offset & 0xfff);
+
+ if (parameters->options().be8())
+ {
+ elfcpp::Swap<32, false>::writeval(pov, plt_insn0);
+ elfcpp::Swap<32, false>::writeval(pov + 4, plt_insn1);
+ elfcpp::Swap<32, false>::writeval(pov + 8, plt_insn2);
+ elfcpp::Swap<32, false>::writeval(pov + 12, plt_insn3);
+ }
+ else
+ {
+ elfcpp::Swap<32, big_endian>::writeval(pov, plt_insn0);
+ elfcpp::Swap<32, big_endian>::writeval(pov + 4, plt_insn1);
+ elfcpp::Swap<32, big_endian>::writeval(pov + 8, plt_insn2);
+ elfcpp::Swap<32, big_endian>::writeval(pov + 12, plt_insn3);
+ }
}
// Write out the PLT. This uses the hand-coded instructions above,
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());
+ 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;
unsigned int plt_offset = this->first_plt_entry_offset();
unsigned int got_offset = 12;
- const unsigned int count = this->count_;
+ const unsigned int count = this->count_ + this->irelative_count_;
+ gold_assert(this->irelative_count_ == this->irelative_data_vec_.size());
for (unsigned int i = 0;
i < count;
++i,
this->fill_plt_entry(pov, got_address, plt_address,
got_offset, plt_offset);
- // Set the entry in the GOT.
- elfcpp::Swap<32, big_endian>::writeval(got_pov, plt_address);
+ Arm_address value;
+ if (i < this->count_)
+ {
+ // For non-irelative got entries, the value is the beginning of plt.
+ value = plt_address;
+ }
+ else
+ {
+ // For irelative got entries, the value is the (global/local) symbol
+ // address.
+ const IRelative_data& idata =
+ this->irelative_data_vec_[i - this->count_];
+ if (idata.symbol_is_global_)
+ {
+ // Set the entry in the GOT for irelative symbols. The content is
+ // the address of the ifunc, not the address of plt start.
+ const Sized_symbol<32>* sized_symbol = idata.u_.global;
+ gold_assert(sized_symbol->type() == elfcpp::STT_GNU_IFUNC);
+ value = sized_symbol->value();
+ }
+ else
+ {
+ value = idata.u_.local.relobj->local_symbol_value(
+ idata.u_.local.index, 0);
+ }
+ }
+ elfcpp::Swap<32, big_endian>::writeval(got_pov, value);
}
gold_assert(static_cast<section_size_type>(pov - oview) == oview_size);
of->write_output_view(got_file_offset, got_size, got_view);
}
+
// Create a PLT entry for a global symbol.
template<bool big_endian>
if (gsym->has_plt_offset())
return;
+ if (this->plt_ == NULL)
+ this->make_plt_section(symtab, layout);
+
+ this->plt_->add_entry(symtab, layout, gsym);
+}
+
+
+// Create the PLT section.
+template<bool big_endian>
+void
+Target_arm<big_endian>::make_plt_section(
+ Symbol_table* symtab, Layout* layout)
+{
if (this->plt_ == NULL)
{
- // Create the GOT sections first.
+ // Create the GOT section first.
this->got_section(symtab, layout);
- this->plt_ = this->make_data_plt(layout, this->got_plt_);
+ // GOT for irelatives is create along with got.plt.
+ gold_assert(this->got_ != NULL
+ && this->got_plt_ != NULL
+ && this->got_irelative_ != NULL);
+ 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);
+ symtab->define_in_output_data("$a", NULL,
+ Symbol_table::PREDEFINED,
+ this->plt_,
+ 0, 0, elfcpp::STT_NOTYPE,
+ elfcpp::STB_LOCAL,
+ elfcpp::STV_DEFAULT, 0,
+ false, false);
}
- this->plt_->add_entry(gsym);
}
+
+// Make a PLT entry for a local STT_GNU_IFUNC symbol.
+
+template<bool big_endian>
+void
+Target_arm<big_endian>::make_local_ifunc_plt_entry(
+ Symbol_table* symtab, Layout* layout,
+ Sized_relobj_file<32, 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);
+}
+
+
// Return the number of entries in the PLT.
template<bool big_endian>
case elfcpp::R_ARM_JUMP_SLOT:
case elfcpp::R_ARM_ABS32:
case elfcpp::R_ARM_ABS32_NOI:
+ case elfcpp::R_ARM_IRELATIVE:
case elfcpp::R_ARM_PC24:
// FIXME: The following 3 types are not supported by Android's dynamic
// linker.
}
}
+
+// Return whether we need to make a PLT entry for a relocation of the
+// given type against a STT_GNU_IFUNC symbol.
+
+template<bool big_endian>
+bool
+Target_arm<big_endian>::Scan::reloc_needs_plt_for_ifunc(
+ Sized_relobj_file<32, big_endian>* object,
+ unsigned int r_type)
+{
+ int flags = Scan::get_reference_flags(r_type);
+ if (flags & Symbol::TLS_REF)
+ {
+ gold_error(_("%s: unsupported TLS reloc %u for IFUNC symbol"),
+ object->name().c_str(), r_type);
+ return false;
+ }
+ return flags != 0;
+}
+
+
// Scan a relocation for a local symbol.
// FIXME: This only handles a subset of relocation types used by Android
// on ARM v5te devices.
if (is_discarded)
return;
- r_type = get_real_reloc_type(r_type);
+ r_type = target->get_real_reloc_type(r_type);
+
+ // 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))
+ {
+ unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
+ target->make_local_ifunc_plt_entry(symtab, layout, object, r_sym);
+ }
+
switch (r_type)
{
case elfcpp::R_ARM_NONE:
// we need to add check_non_pic(object, r_type) here.
rel_dyn->add_local_relative(object, r_sym, elfcpp::R_ARM_RELATIVE,
output_section, data_shndx,
- reloc.get_r_offset());
+ reloc.get_r_offset(), is_ifunc);
}
break;
&& strcmp(gsym->name(), "_GLOBAL_OFFSET_TABLE_") == 0)
target->got_section(symtab, layout);
- r_type = get_real_reloc_type(r_type);
+ // 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);
+
+ r_type = target->get_real_reloc_type(r_type);
switch (r_type)
{
case elfcpp::R_ARM_NONE:
target->copy_reloc(symtab, layout, object,
data_shndx, output_section, gsym, reloc);
}
+ else if ((r_type == elfcpp::R_ARM_ABS32
+ || r_type == elfcpp::R_ARM_ABS32_NOI)
+ && 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* rel_irelative =
+ target->rel_irelative_section(layout);
+ unsigned int r_type = elfcpp::R_ARM_IRELATIVE;
+ rel_irelative->add_symbolless_global_addend(
+ gsym, r_type, output_section, object,
+ data_shndx, reloc.get_r_offset());
+ }
else if ((r_type == elfcpp::R_ARM_ABS32
|| r_type == elfcpp::R_ARM_ABS32_NOI)
&& gsym->can_use_relative_reloc(false))
Arm_output_data_got<big_endian>* got =
target->got_section(symtab, layout);
if (gsym->final_value_is_known())
- got->add_global(gsym, GOT_TYPE_STANDARD);
+ {
+ // 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
|| gsym->is_undefined()
|| gsym->is_preemptible()
|| (gsym->visibility() == elfcpp::STV_PROTECTED
- && parameters->options().shared()))
+ && parameters->options().shared())
+ || (gsym->type() == elfcpp::STT_GNU_IFUNC
+ && parameters->options().output_is_position_independent()))
got->add_global_with_rel(gsym, GOT_TYPE_STANDARD,
rel_dyn, elfcpp::R_ARM_GLOB_DAT);
else
{
- if (got->add_global(gsym, GOT_TYPE_STANDARD))
+ // 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)
rel_dyn->add_global_relative(
gsym, elfcpp::R_ARM_RELATIVE, got,
gsym->got_offset(GOT_TYPE_STANDARD));
typedef Target_arm<big_endian> Arm;
typedef typename Target_arm<big_endian>::Scan Scan;
- gold::gc_process_relocs<32, big_endian, Arm, elfcpp::SHT_REL, Scan,
- typename Target_arm::Relocatable_size_for_reloc>(
+ gold::gc_process_relocs<32, big_endian, Arm, Scan, Classify_reloc>(
symtab,
layout,
this,
size_t local_symbol_count,
const unsigned char* plocal_symbols)
{
- typedef typename Target_arm<big_endian>::Scan Scan;
if (sh_type == elfcpp::SHT_RELA)
{
gold_error(_("%s: unsupported RELA reloc section"),
return;
}
- gold::scan_relocs<32, big_endian, Target_arm, elfcpp::SHT_REL, Scan>(
+ gold::scan_relocs<32, big_endian, Target_arm, Scan, Classify_reloc>(
symtab,
layout,
this,
inline bool
Target_arm<big_endian>::Relocate::relocate(
const Relocate_info<32, big_endian>* relinfo,
+ unsigned int,
Target_arm* target,
Output_section* output_section,
size_t relnum,
- const elfcpp::Rel<32, big_endian>& rel,
- unsigned int r_type,
+ const unsigned char* preloc,
const Sized_symbol<32>* gsym,
const Symbol_value<32>* psymval,
unsigned char* view,
typedef Arm_relocate_functions<big_endian> Arm_relocate_functions;
- r_type = get_real_reloc_type(r_type);
+ const elfcpp::Rel<32, big_endian> rel(preloc);
+ unsigned int r_type = elfcpp::elf_r_type<32>(rel.get_r_info());
+ r_type = target->get_real_reloc_type(r_type);
const Arm_reloc_property* reloc_property =
arm_reloc_property_table->get_implemented_static_reloc_property(r_type);
if (reloc_property == NULL)
if (gsym->use_plt_offset(Scan::get_reference_flags(r_type)))
{
// This uses a PLT, change the symbol value.
- symval.set_output_value(target->plt_section()->address()
- + gsym->plt_offset());
+ symval.set_output_value(target->plt_address_for_global(gsym));
psymval = &symval;
}
else if (gsym->is_weak_undefined())
elfcpp::Elf_types<32>::Elf_WXword r_info = rel.get_r_info();
unsigned int r_sym = elfcpp::elf_r_sym<32>(r_info);
thumb_bit = object->local_symbol_is_thumb_function(r_sym) ? 1 : 0;
+
+ if (psymval->is_ifunc_symbol() && object->local_has_plt_offset(r_sym))
+ {
+ symval.set_output_value(
+ target->plt_address_for_local(object, r_sym));
+ psymval = &symval;
+ }
}
}
else
}
}
- gold::relocate_section<32, big_endian, Target_arm, elfcpp::SHT_REL,
- Arm_relocate, gold::Default_comdat_behavior>(
+ gold::relocate_section<32, big_endian, Target_arm, Arm_relocate,
+ gold::Default_comdat_behavior, Classify_reloc>(
relinfo,
this,
prelocs,
template<bool big_endian>
unsigned int
-Target_arm<big_endian>::Relocatable_size_for_reloc::get_size_for_reloc(
+Target_arm<big_endian>::Classify_reloc::get_size_for_reloc(
unsigned int r_type,
Relobj* object)
{
- r_type = get_real_reloc_type(r_type);
+ Target_arm<big_endian>* arm_target =
+ Target_arm<big_endian>::default_target();
+ r_type = arm_target->get_real_reloc_type(r_type);
const Arm_reloc_property* arp =
arm_reloc_property_table->get_implemented_static_reloc_property(r_type);
if (arp != NULL)
const unsigned char* plocal_symbols,
Relocatable_relocs* rr)
{
- gold_assert(sh_type == elfcpp::SHT_REL);
+ typedef Arm_scan_relocatable_relocs<big_endian, Classify_reloc>
+ Scan_relocatable_relocs;
- typedef Arm_scan_relocatable_relocs<big_endian, elfcpp::SHT_REL,
- Relocatable_size_for_reloc> Scan_relocatable_relocs;
+ gold_assert(sh_type == elfcpp::SHT_REL);
- gold::scan_relocatable_relocs<32, big_endian, elfcpp::SHT_REL,
- Scan_relocatable_relocs>(
+ gold::scan_relocatable_relocs<32, big_endian, Scan_relocatable_relocs>(
symtab,
layout,
object,
rr);
}
+// Scan the relocs for --emit-relocs.
+
+template<bool big_endian>
+void
+Target_arm<big_endian>::emit_relocs_scan(Symbol_table* symtab,
+ Layout* layout,
+ Sized_relobj_file<32, 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_syms,
+ Relocatable_relocs* rr)
+{
+ typedef gold::Default_classify_reloc<elfcpp::SHT_REL, 32, big_endian>
+ Classify_reloc;
+ typedef gold::Default_emit_relocs_strategy<Classify_reloc>
+ Emit_relocs_strategy;
+
+ gold_assert(sh_type == elfcpp::SHT_REL);
+
+ gold::scan_relocatable_relocs<32, big_endian, Emit_relocs_strategy>(
+ symtab,
+ layout,
+ object,
+ data_shndx,
+ prelocs,
+ reloc_count,
+ output_section,
+ needs_special_offset_handling,
+ local_symbol_count,
+ plocal_syms,
+ rr);
+}
+
// Emit relocations for a section.
template<bool big_endian>
size_t reloc_count,
Output_section* output_section,
typename elfcpp::Elf_types<32>::Elf_Off offset_in_output_section,
- const Relocatable_relocs* rr,
unsigned char* view,
Arm_address view_address,
section_size_type view_size,
{
gold_assert(sh_type == elfcpp::SHT_REL);
- gold::relocate_relocs<32, big_endian, elfcpp::SHT_REL>(
+ gold::relocate_relocs<32, big_endian, Classify_reloc>(
relinfo,
prelocs,
reloc_count,
output_section,
offset_in_output_section,
- rr,
view,
view_address,
view_size,
Target_arm<big_endian>::do_dynsym_value(const Symbol* gsym) const
{
gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset());
- return this->plt_section()->address() + gsym->plt_offset();
+ return this->plt_address_for_global(gsym);
}
// Map platform-specific relocs to real relocs
//
template<bool big_endian>
unsigned int
-Target_arm<big_endian>::get_real_reloc_type(unsigned int r_type)
+Target_arm<big_endian>::get_real_reloc_type(unsigned int r_type) const
{
switch (r_type)
{
case elfcpp::R_ARM_TARGET1:
- // This is either R_ARM_ABS32 or R_ARM_REL32;
- return elfcpp::R_ARM_ABS32;
+ return this->target1_reloc_;
case elfcpp::R_ARM_TARGET2:
- // This can be any reloc type but usually is R_ARM_GOT_PREL
- return elfcpp::R_ARM_GOT_PREL;
+ return this->target2_reloc_;
default:
return r_type;
e_ident[elfcpp::EI_OSABI] = 0;
e_ident[elfcpp::EI_ABIVERSION] = 0;
- // FIXME: Do EF_ARM_BE8 adjustment.
+ // Do EF_ARM_BE8 adjustment.
+ if (parameters->options().be8() && !big_endian)
+ gold_error("BE8 images only valid in big-endian mode.");
+ if (parameters->options().be8())
+ {
+ flags |= elfcpp::EF_ARM_BE8;
+ this->set_processor_specific_flags(flags);
+ }
// If we're working in EABI_VER5, set the hard/soft float ABI flags
// as appropriate.
if (type == elfcpp::ET_EXEC || type == elfcpp::ET_DYN)
{
Object_attribute* attr = this->get_aeabi_object_attribute(elfcpp::Tag_ABI_VFP_args);
- if (attr->int_value())
+ if (attr->int_value() == elfcpp::AEABI_VFP_args_vfp)
flags |= elfcpp::EF_ARM_ABI_FLOAT_HARD;
else
flags |= elfcpp::EF_ARM_ABI_FLOAT_SOFT;
}
elfcpp::Ehdr_write<32, big_endian> oehdr(view);
oehdr.put_e_ident(e_ident);
+ oehdr.put_e_flags(this->processor_specific_flags());
}
// do_make_elf_object to override the same function in the base class.
T(V7E_M), // V6S_M.
T(V7E_M) // V7E_M.
};
+ static const int v8[] =
+ {
+ T(V8), // PRE_V4.
+ T(V8), // V4.
+ T(V8), // V4T.
+ T(V8), // V5T.
+ T(V8), // V5TE.
+ T(V8), // V5TEJ.
+ T(V8), // V6.
+ T(V8), // V6KZ.
+ T(V8), // V6T2.
+ T(V8), // V6K.
+ T(V8), // V7.
+ T(V8), // V6_M.
+ T(V8), // V6S_M.
+ T(V8), // V7E_M.
+ T(V8) // V8.
+ };
static const int v4t_plus_v6_m[] =
{
-1, // PRE_V4.
T(V6_M), // V6_M.
T(V6S_M), // V6S_M.
T(V7E_M), // V7E_M.
+ T(V8), // V8.
T(V4T_PLUS_V6_M) // V4T plus V6_M.
};
static const int* comb[] =
v6_m,
v6s_m,
v7e_m,
+ v8,
// Pseudo-architecture.
v4t_plus_v6_m
};
"ARM v7",
"ARM v6-M",
"ARM v6S-M",
- "ARM v7E-M"
+ "ARM v7E-M",
+ "ARM v8"
};
const size_t name_table_size = sizeof(name_table) / sizeof(name_table[0]);
{
case 0:
// Integer divide allowed if instruction contained in
- // archetecture.
+ // architecture.
if (arch == elfcpp::TAG_CPU_ARCH_V7 && (profile == 'R' || profile == 'M'))
return true;
else if (arch >= elfcpp::TAG_CPU_ARCH_V7E_M)
!= out_attr[elfcpp::Tag_ABI_VFP_args].int_value())
{
// Ignore mismatches if the object doesn't use floating point. */
- if (out_attr[elfcpp::Tag_ABI_FP_number_model].int_value() == 0)
+ if (out_attr[elfcpp::Tag_ABI_FP_number_model].int_value()
+ == elfcpp::AEABI_FP_number_model_none
+ || (in_attr[elfcpp::Tag_ABI_FP_number_model].int_value()
+ != elfcpp::AEABI_FP_number_model_none
+ && out_attr[elfcpp::Tag_ABI_VFP_args].int_value()
+ == elfcpp::AEABI_VFP_args_compatible))
out_attr[elfcpp::Tag_ABI_VFP_args].set_int_value(
in_attr[elfcpp::Tag_ABI_VFP_args].int_value());
- else if (in_attr[elfcpp::Tag_ABI_FP_number_model].int_value() != 0
+ else if (in_attr[elfcpp::Tag_ABI_FP_number_model].int_value()
+ != elfcpp::AEABI_FP_number_model_none
+ && in_attr[elfcpp::Tag_ABI_VFP_args].int_value()
+ != elfcpp::AEABI_VFP_args_compatible
&& parameters->options().warn_mismatch())
gold_error(_("%s uses VFP register arguments, output does not"),
name);
if (in_attr[elfcpp::Tag_MPextension_use].int_value()
!= in_attr[i].int_value())
{
- gold_error(_("%s has has both the current and legacy "
+ gold_error(_("%s has both the current and legacy "
"Tag_MPextension_use attributes"),
name);
}
if (gsym->use_plt_offset(Scan::get_reference_flags(r_type)))
{
// This uses a PLT, change the symbol value.
- symval.set_output_value(this->plt_section()->address()
- + gsym->plt_offset());
+ symval.set_output_value(this->plt_address_for_global(gsym));
psymval = &symval;
target_is_thumb = false;
}
const Symbol_value<32> *psymval;
bool is_defined_in_discarded_section;
unsigned int shndx;
+ const Symbol* gsym = NULL;
if (r_sym < local_count)
{
sym = NULL;
if (!is_defined_in_discarded_section)
{
typedef Sized_relobj_file<32, big_endian> ObjType;
+ if (psymval->is_section_symbol())
+ symval.set_is_section_symbol();
typename ObjType::Compute_final_local_value_status status =
arm_object->compute_final_local_value(r_sym, psymval, &symval,
relinfo->symtab);
}
else
{
- const Symbol* gsym;
gsym = arm_object->global_symbol(r_sym);
gold_assert(gsym != NULL);
if (gsym->is_forwarder())
Symbol_value<32> symval2;
if (is_defined_in_discarded_section)
{
+ std::string name = arm_object->section_name(relinfo->data_shndx);
+
if (comdat_behavior == CB_UNDETERMINED)
- {
- std::string name = arm_object->section_name(relinfo->data_shndx);
comdat_behavior = default_comdat_behavior.get(name.c_str());
- }
+
if (comdat_behavior == CB_PRETEND)
{
// FIXME: This case does not work for global symbols.
// script.
bool found;
typename elfcpp::Elf_types<32>::Elf_Addr value =
- arm_object->map_to_kept_section(shndx, &found);
+ arm_object->map_to_kept_section(shndx, name, &found);
if (found)
symval2.set_output_value(value + psymval->input_value());
else
}
else
{
- if (comdat_behavior == CB_WARNING)
- gold_warning_at_location(relinfo, i, offset,
- _("relocation refers to discarded "
- "section"));
+ if (comdat_behavior == CB_ERROR)
+ issue_discarded_error(relinfo, i, offset, r_sym, gsym);
symval2.set_output_value(0);
}
symval2.set_no_output_symtab_entry();
elfcpp::Rel_write<32, big_endian> reloc_write(reloc_buffer);
reloc_write.put_r_offset(reloc_offset);
reloc_write.put_r_info(elfcpp::elf_r_info<32>(0, r_type));
- elfcpp::Rel<32, big_endian> rel(reloc_buffer);
- relocate.relocate(relinfo, this, output_section,
- this->fake_relnum_for_stubs, rel, r_type,
+ relocate.relocate(relinfo, elfcpp::SHT_REL, this, output_section,
+ this->fake_relnum_for_stubs, reloc_buffer,
NULL, &symval, view + reloc_offset,
address + reloc_offset, reloc_size);
}
Arm_address target = (pc_for_insn + offset) | (is_blx ? 0 : 1);
- // Add a new stub if destination address in in the same page.
+ // Add a new stub if destination address is in the same page.
if (((address + i) & ~0xfffU) == (target & ~0xfffU))
{
Cortex_a8_stub* stub =
// branch to the stub. We use the THUMB-2 encoding here.
upper_insn = 0xf000U;
lower_insn = 0xb800U;
- // Fall through
+ // Fall through.
case arm_stub_a8_veneer_b:
case arm_stub_a8_veneer_bl:
case arm_stub_a8_veneer_blx:
const Task* task)
{
// We need to look at all the input sections in output in ascending
- // order of of output address. We do that by building a sorted list
+ // order of output address. We do that by building a sorted list
// of output sections by addresses. Then we looks at the output sections
// in order. The input sections in an output section are already sorted
// by addresses within the output section.
protected:
virtual Output_data_plt_arm<big_endian>*
- do_make_data_plt(Layout* layout, Output_data_space* got_plt)
- { return new Output_data_plt_arm_nacl<big_endian>(layout, got_plt); }
+ do_make_data_plt(
+ Layout* layout,
+ Arm_output_data_got<big_endian>* got,
+ Output_data_space* got_plt,
+ Output_data_space* got_irelative)
+ { return new Output_data_plt_arm_nacl<big_endian>(
+ layout, got, got_plt, got_irelative); }
private:
static const Target::Target_info arm_nacl_info;
0, // large_common_section_flags
".ARM.attributes", // attributes_section
"aeabi", // attributes_vendor
- "_start" // entry_symbol_name
+ "_start", // entry_symbol_name
+ 32, // hash_entry_size
+ elfcpp::SHT_PROGBITS, // unwind_section_type
};
template<bool big_endian>
class Output_data_plt_arm_nacl : public Output_data_plt_arm<big_endian>
{
public:
- Output_data_plt_arm_nacl(Layout* layout, Output_data_space* got_plt)
- : Output_data_plt_arm<big_endian>(layout, 16, got_plt)
+ Output_data_plt_arm_nacl(
+ Layout* layout,
+ Arm_output_data_got<big_endian>* got,
+ Output_data_space* got_plt,
+ Output_data_space* got_irelative)
+ : Output_data_plt_arm<big_endian>(layout, 16, got, got_plt, got_irelative)
{ }
protected:
projects / deliverable / binutils-gdb.git / blobdiff