// arm.cc -- arm target support for gold.
-// Copyright (C) 2009-2015 Free Software Foundation, Inc.
+// Copyright (C) 2009-2016 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;
// 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
{
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,
Output_data_space* got_irelative)
{
gold_assert(got_plt != NULL && got_irelative != NULL);
- return new Output_data_plt_arm_standard<big_endian>(
+ 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);
}
// 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*);
};
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));
}
0, // large_common_section_flags
".ARM.attributes", // attributes_section
"aeabi", // attributes_vendor
- "_start" // entry_symbol_name
+ "_start", // entry_symbol_name
+ 32, // hash_entry_size
};
// Arm relocate functions class
// 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();
}
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]);
// Last word in first PLT entry is &GOT[0] - .
}
// 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 + 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);
+ elfcpp::Swap<32, big_endian>::writeval(pov, plt_insn0);
+ uint32_t plt_insn1 = plt_entry[1] | ((offset >> 20) & 0xff);
+ elfcpp::Swap<32, big_endian>::writeval(pov + 4, plt_insn1);
+ uint32_t plt_insn2 = plt_entry[2] | ((offset >> 12) & 0xff);
+ elfcpp::Swap<32, big_endian>::writeval(pov + 8, plt_insn2);
+ uint32_t plt_insn3 = plt_entry[3] | (offset & 0xfff);
+ elfcpp::Swap<32, big_endian>::writeval(pov + 12, plt_insn3);
+}
+
// Write out the PLT. This uses the hand-coded instructions above,
// and adjusts them as needed. This is all specified by the arm ELF
// Processor Supplement.
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;
+ const elfcpp::Rel<32, big_endian> rel(preloc);
+ unsigned int r_type = elfcpp::elf_r_type<32>(rel.get_r_info());
r_type = get_real_reloc_type(r_type);
const Arm_reloc_property* reloc_property =
arm_reloc_property_table->get_implemented_static_reloc_property(r_type);
}
}
- 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)
{
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,
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);
}
0, // large_common_section_flags
".ARM.attributes", // attributes_section
"aeabi", // attributes_vendor
- "_start" // entry_symbol_name
+ "_start", // entry_symbol_name
+ 32, // hash_entry_size
};
template<bool big_endian>