// i386.cc -- i386 target support for gold.
-// Copyright 2006, 2007, 2008, 2009, 2010, 2011, 2012
-// Free Software Foundation, Inc.
+// Copyright (C) 2006-2019 Free Software Foundation, Inc.
// Written by Ian Lance Taylor <iant@google.com>.
// This file is part of gold.
using namespace gold;
+// A class to handle the .got.plt section.
+
+class Output_data_got_plt_i386 : public Output_section_data_build
+{
+ public:
+ Output_data_got_plt_i386(Layout* layout)
+ : Output_section_data_build(4),
+ layout_(layout)
+ { }
+
+ protected:
+ // Write out the PLT data.
+ void
+ do_write(Output_file*);
+
+ // Write to a map file.
+ void
+ do_print_to_mapfile(Mapfile* mapfile) const
+ { mapfile->print_output_data(this, "** GOT PLT"); }
+
+ private:
+ // A pointer to the Layout class, so that we can find the .dynamic
+ // section when we write out the GOT PLT section.
+ Layout* layout_;
+};
+
// 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
typedef Output_data_reloc<elfcpp::SHT_REL, true, 32, false> Reloc_section;
Output_data_plt_i386(Layout*, uint64_t addralign,
- Output_data_space*, Output_data_space*);
+ Output_data_got_plt_i386*, Output_data_space*);
// Add an entry to the PLT.
void
unsigned int got_offset;
};
- // A pointer to the Layout class, so that we can find the .dynamic
- // section when we write out the GOT PLT section.
- Layout* layout_;
// The reloc section.
Reloc_section* rel_;
// The TLS_DESC relocations, if necessary. These must follow the
// regular relocatoins and the TLS_DESC relocations.
Reloc_section* irelative_rel_;
// The .got.plt section.
- Output_data_space* got_plt_;
+ Output_data_got_plt_i386* got_plt_;
// The part of the .got.plt section used for IRELATIVE relocs.
Output_data_space* got_irelative_;
// The number of PLT entries.
{
public:
Output_data_plt_i386_standard(Layout* layout,
- Output_data_space* got_plt,
+ Output_data_got_plt_i386* got_plt,
Output_data_space* got_irelative)
: Output_data_plt_i386(layout, plt_entry_size, got_plt, got_irelative)
{ }
{
public:
Output_data_plt_i386_exec(Layout* layout,
- Output_data_space* got_plt,
+ Output_data_got_plt_i386* got_plt,
Output_data_space* got_irelative)
: Output_data_plt_i386_standard(layout, got_plt, got_irelative)
{ }
{
public:
Output_data_plt_i386_dyn(Layout* layout,
- Output_data_space* got_plt,
+ Output_data_got_plt_i386* got_plt,
Output_data_space* got_irelative)
: Output_data_plt_i386_standard(layout, got_plt, got_irelative)
{ }
: Sized_target<32, false>(info),
got_(NULL), plt_(NULL), got_plt_(NULL), got_irelative_(NULL),
got_tlsdesc_(NULL), global_offset_table_(NULL), rel_dyn_(NULL),
- rel_irelative_(NULL), copy_relocs_(elfcpp::R_386_COPY), dynbss_(NULL),
+ rel_irelative_(NULL), copy_relocs_(elfcpp::R_386_COPY),
got_mod_index_offset_(-1U), tls_base_symbol_defined_(false)
{ }
const unsigned char* plocal_symbols,
Relocatable_relocs*);
- // Relocate a section during a relocatable link.
+ // Scan the relocs for --emit-relocs.
+ void
+ emit_relocs_scan(Symbol_table* symtab,
+ Layout* layout,
+ Sized_relobj_file<32, false>* 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_for_relocatable(const Relocate_info<32, false>*,
- unsigned int sh_type,
- const unsigned char* prelocs,
- size_t reloc_count,
- Output_section* output_section,
- off_t offset_in_output_section,
- const Relocatable_relocs*,
- unsigned char* view,
- elfcpp::Elf_types<32>::Elf_Addr view_address,
- section_size_type view_size,
- unsigned char* reloc_view,
- section_size_type reloc_view_size);
+ relocate_relocs(const Relocate_info<32, false>*,
+ unsigned int sh_type,
+ const unsigned char* prelocs,
+ size_t reloc_count,
+ Output_section* output_section,
+ elfcpp::Elf_types<32>::Elf_Off offset_in_output_section,
+ unsigned char* view,
+ elfcpp::Elf_types<32>::Elf_Addr view_address,
+ section_size_type view_size,
+ unsigned char* reloc_view,
+ section_size_type reloc_view_size);
// Return a string used to fill a code section with nops.
std::string
// Return whether SYM is call to a non-split function.
bool
- do_is_call_to_non_split(const Symbol* sym, unsigned int) const;
+ do_is_call_to_non_split(const Symbol* sym, const unsigned char*,
+ const unsigned char*, section_size_type) const;
// Adjust -fsplit-stack code which calls non-split-stack code.
void
do_calls_non_split(Relobj* object, unsigned int shndx,
section_offset_type fnoffset, section_size_type fnsize,
+ const unsigned char* prelocs, size_t reloc_count,
unsigned char* view, section_size_type view_size,
std::string* from, std::string* to) const;
// This chooses the right PLT flavor for an executable or a shared object.
Output_data_plt_i386*
make_data_plt(Layout* layout,
- Output_data_space* got_plt,
+ Output_data_got_plt_i386* got_plt,
Output_data_space* got_irelative,
bool dyn)
{ return this->do_make_data_plt(layout, got_plt, got_irelative, dyn); }
virtual Output_data_plt_i386*
do_make_data_plt(Layout* layout,
- Output_data_space* got_plt,
+ Output_data_got_plt_i386* got_plt,
Output_data_space* got_irelative,
bool dyn)
{
unsigned int data_shndx,
Output_section* output_section,
const elfcpp::Rel<32, false>& reloc, unsigned int r_type,
- const elfcpp::Sym<32, false>& lsym);
+ const elfcpp::Sym<32, false>& lsym,
+ bool is_discarded);
inline void
global(Symbol_table* symtab, Layout* layout, Target_i386* target,
// Do a relocation. Return false if the caller should not issue
// any warnings about this relocation.
inline bool
- relocate(const Relocate_info<32, false>*, Target_i386*, Output_section*,
- size_t relnum, const elfcpp::Rel<32, false>&,
- unsigned int r_type, const Sized_symbol<32>*,
- const Symbol_value<32>*,
+ relocate(const Relocate_info<32, false>*, unsigned int,
+ Target_i386*, Output_section*, size_t, const unsigned char*,
+ const Sized_symbol<32>*, const Symbol_value<32>*,
unsigned char*, elfcpp::Elf_types<32>::Elf_Addr,
section_size_type);
// Do a TLS General-Dynamic to Initial-Exec transition.
inline void
tls_gd_to_ie(const Relocate_info<32, false>*, size_t relnum,
- Output_segment* tls_segment,
const elfcpp::Rel<32, false>&, unsigned int r_type,
elfcpp::Elf_types<32>::Elf_Addr value,
unsigned char* view,
// transition.
inline void
tls_desc_gd_to_ie(const Relocate_info<32, false>*, size_t relnum,
- Output_segment* tls_segment,
const elfcpp::Rel<32, false>&, unsigned int r_type,
elfcpp::Elf_types<32>::Elf_Addr value,
unsigned char* view,
Local_dynamic_type local_dynamic_type_;
};
- // 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, false>
{
public:
- unsigned int
+ typedef Reloc_types<elfcpp::SHT_REL, 32, false>::Reloc Reltype;
+
+ // Return the explicit addend of the relocation (return 0 for SHT_REL).
+ static 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*);
};
static tls::Tls_optimization
optimize_tls_reloc(bool is_final, int r_type);
+ // Check if relocation against this symbol is a candidate for
+ // conversion from
+ // mov foo@GOT(%reg), %reg
+ // to
+ // lea foo@GOTOFF(%reg), %reg.
+ static bool
+ can_convert_mov_to_lea(const Symbol* gsym)
+ {
+ gold_assert(gsym != NULL);
+ return (gsym->type() != elfcpp::STT_GNU_IFUNC
+ && !gsym->is_undefined ()
+ && !gsym->is_from_dynobj()
+ && !gsym->is_preemptible()
+ && (!parameters->options().shared()
+ || (gsym->visibility() != elfcpp::STV_DEFAULT
+ && gsym->visibility() != elfcpp::STV_PROTECTED)
+ || parameters->options().Bsymbolic())
+ && strcmp(gsym->name(), "_DYNAMIC") != 0);
+ }
+
// Get the GOT section, creating it if necessary.
Output_data_got<32, false>*
got_section(Symbol_table*, Layout*);
// Get the GOT PLT section.
- Output_data_space*
+ Output_data_got_plt_i386*
got_plt_section() const
{
gold_assert(this->got_plt_ != NULL);
unsigned int shndx, Output_section* output_section,
Symbol* sym, const elfcpp::Rel<32, false>& 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));
}
// The PLT section.
Output_data_plt_i386* plt_;
// The GOT PLT section.
- Output_data_space* got_plt_;
+ Output_data_got_plt_i386* got_plt_;
// The GOT section for IRELATIVE relocations.
Output_data_space* got_irelative_;
// The GOT section for TLSDESC relocations.
Reloc_section* rel_irelative_;
// Relocs saved to avoid a COPY reloc.
Copy_relocs<elfcpp::SHT_REL, 32, false> copy_relocs_;
- // Space for variables copied with a COPY reloc.
- Output_data_space* dynbss_;
// Offset of the GOT entry for the TLS module index.
unsigned int got_mod_index_offset_;
// True if the _TLS_MODULE_BASE_ symbol has been defined.
0, // small_common_section_flags
0, // large_common_section_flags
NULL, // attributes_section
- NULL // attributes_vendor
+ NULL, // attributes_vendor
+ "_start", // entry_symbol_name
+ 32, // hash_entry_size
+ elfcpp::SHT_PROGBITS, // unwind_section_type
};
// Get the GOT section, creating it if necessary.
| elfcpp::SHF_WRITE),
this->got_, got_order, true);
- this->got_plt_ = new Output_data_space(4, "** GOT PLT");
+ this->got_plt_ = new Output_data_got_plt_i386(layout);
layout->add_output_section_data(".got.plt", elfcpp::SHT_PROGBITS,
(elfcpp::SHF_ALLOC
| elfcpp::SHF_WRITE),
return this->rel_irelative_;
}
+// Write the first three reserved words of the .got.plt section.
+// The remainder of the section is written while writing the PLT
+// in Output_data_plt_i386::do_write.
+
+void
+Output_data_got_plt_i386::do_write(Output_file* of)
+{
+ // The first entry in the GOT is the address of the .dynamic section
+ // aka the PT_DYNAMIC segment. The next two entries are reserved.
+ // We saved space for them when we created the section in
+ // Target_i386::got_section.
+ const off_t got_file_offset = this->offset();
+ gold_assert(this->data_size() >= 12);
+ unsigned char* const got_view = of->get_output_view(got_file_offset, 12);
+ Output_section* dynamic = this->layout_->dynamic_section();
+ uint32_t dynamic_addr = dynamic == NULL ? 0 : dynamic->address();
+ elfcpp::Swap<32, false>::writeval(got_view, dynamic_addr);
+ memset(got_view + 4, 0, 8);
+ of->write_output_view(got_file_offset, 12, got_view);
+}
+
// Create the PLT section. The ordinary .got section is an argument,
// since we need to refer to the start. We also create our own .got
// section just for PLT entries.
Output_data_plt_i386::Output_data_plt_i386(Layout* layout,
uint64_t addralign,
- Output_data_space* got_plt,
+ Output_data_got_plt_i386* got_plt,
Output_data_space* got_irelative)
: Output_section_data(addralign),
- layout_(layout), tls_desc_rel_(NULL),
- irelative_rel_(NULL), got_plt_(got_plt), got_irelative_(got_irelative),
- count_(0), irelative_count_(0), global_ifuncs_(), local_ifuncs_()
+ tls_desc_rel_(NULL), irelative_rel_(NULL), got_plt_(got_plt),
+ got_irelative_(got_irelative), count_(0), irelative_count_(0),
+ global_ifuncs_(), local_ifuncs_()
{
this->rel_ = new Reloc_section(false);
layout->add_output_section_data(".rel.plt", elfcpp::SHT_REL,
if (gsym->type() == elfcpp::STT_GNU_IFUNC
&& gsym->can_use_relative_reloc(false))
offset = (this->count_ + 1) * this->get_plt_entry_size();
- return this->address() + offset;
+ return this->address() + offset + gsym->plt_offset();
}
// Return the PLT address to use for a local symbol. These are always
// IRELATIVE relocs.
uint64_t
-Output_data_plt_i386::address_for_local(const Relobj*, unsigned int)
+Output_data_plt_i386::address_for_local(const Relobj* object,
+ unsigned int r_sym)
{
- return this->address() + (this->count_ + 1) * this->get_plt_entry_size();
+ return (this->address()
+ + (this->count_ + 1) * this->get_plt_entry_size()
+ + object->local_plt_offset(r_sym));
}
// The first entry in the PLT for an executable.
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);
this->fill_first_plt_entry(pov, got_address);
pov += this->get_plt_entry_size();
- unsigned char* got_pov = got_view;
-
- // The first entry in the GOT is the address of the .dynamic section
- // aka the PT_DYNAMIC segment. The next two entries are reserved.
- // We saved space for them when we created the section in
- // Target_i386::got_section.
- Output_section* dynamic = this->layout_->dynamic_section();
- uint32_t dynamic_addr = dynamic == NULL ? 0 : dynamic->address();
- elfcpp::Swap<32, false>::writeval(got_pov, dynamic_addr);
- got_pov += 4;
- memset(got_pov, 0, 8);
- got_pov += 8;
+ // The first three entries in the GOT are reserved, and are written
+ // by Output_data_got_plt_i386::do_write.
+ unsigned char* got_pov = got_view + 12;
const int rel_size = elfcpp::Elf_sizes<32>::rel_size;
unsigned int
Target_i386::first_plt_entry_offset() const
{
+ if (this->plt_ == NULL)
+ return 0;
return this->plt_->first_plt_entry_offset();
}
unsigned int
Target_i386::plt_entry_size() const
{
+ if (this->plt_ == NULL)
+ return 0;
return this->plt_->get_plt_entry_size();
}
return Symbol::FUNCTION_CALL | Symbol::RELATIVE_REF;
case elfcpp::R_386_GOT32:
+ case elfcpp::R_386_GOT32X:
// Absolute in GOT.
return Symbol::ABSOLUTE_REF;
inline void
Target_i386::Scan::local(Symbol_table* symtab,
- Layout* layout,
- Target_i386* target,
- Sized_relobj_file<32, false>* object,
- unsigned int data_shndx,
- Output_section* output_section,
- const elfcpp::Rel<32, false>& reloc,
- unsigned int r_type,
- const elfcpp::Sym<32, false>& lsym)
+ Layout* layout,
+ Target_i386* target,
+ Sized_relobj_file<32, false>* object,
+ unsigned int data_shndx,
+ Output_section* output_section,
+ const elfcpp::Rel<32, false>& reloc,
+ unsigned int r_type,
+ const elfcpp::Sym<32, false>& lsym,
+ bool is_discarded)
{
+ if (is_discarded)
+ return;
+
// A local STT_GNU_IFUNC symbol may require a PLT entry.
if (lsym.get_st_type() == elfcpp::STT_GNU_IFUNC
&& this->reloc_needs_plt_for_ifunc(object, r_type))
break;
case elfcpp::R_386_GOT32:
+ case elfcpp::R_386_GOT32X:
{
- // The symbol requires a GOT entry.
+ // We need GOT section.
Output_data_got<32, false>* got = target->got_section(symtab, layout);
+
+ // If the relocation symbol isn't IFUNC,
+ // and is local, then we will convert
+ // mov foo@GOT(%reg), %reg
+ // to
+ // lea foo@GOTOFF(%reg), %reg
+ // in Relocate::relocate.
+ if (reloc.get_r_offset() >= 2
+ && lsym.get_st_type() != elfcpp::STT_GNU_IFUNC)
+ {
+ section_size_type stype;
+ const unsigned char* view = object->section_contents(data_shndx,
+ &stype, true);
+ if (view[reloc.get_r_offset() - 2] == 0x8b)
+ break;
+ }
+
+ // Otherwise, the symbol requires a GOT entry.
unsigned int r_sym = elfcpp::elf_r_sym<32>(reloc.get_r_info());
// For a STT_GNU_IFUNC symbol we want the PLT offset. That
got->add_local_pair_with_rel(object, r_sym, shndx,
GOT_TYPE_TLS_PAIR,
target->rel_dyn_section(layout),
- elfcpp::R_386_TLS_DTPMOD32, 0);
+ elfcpp::R_386_TLS_DTPMOD32);
}
else if (optimized_type != tls::TLSOPT_TO_LE)
unsupported_reloc_local(object, r_type);
case elfcpp::R_386_8:
case elfcpp::R_386_GOTOFF:
case elfcpp::R_386_GOT32:
+ case elfcpp::R_386_GOT32X:
{
return true;
}
// Make a dynamic relocation if necessary.
if (gsym->needs_dynamic_reloc(Scan::get_reference_flags(r_type)))
{
- if (gsym->may_need_copy_reloc())
+ if (!parameters->options().output_is_position_independent()
+ && gsym->may_need_copy_reloc())
{
target->copy_reloc(symtab, layout, object,
data_shndx, output_section, gsym, reloc);
// Make a dynamic relocation if necessary.
if (gsym->needs_dynamic_reloc(Scan::get_reference_flags(r_type)))
{
- if (gsym->may_need_copy_reloc())
+ if (parameters->options().output_is_executable()
+ && gsym->may_need_copy_reloc())
{
target->copy_reloc(symtab, layout, object,
data_shndx, output_section, gsym, reloc);
break;
case elfcpp::R_386_GOT32:
+ case elfcpp::R_386_GOT32X:
{
- // The symbol requires a GOT entry.
+ // The symbol requires a GOT section.
Output_data_got<32, false>* got = target->got_section(symtab, layout);
+
+ // If we convert this from
+ // mov foo@GOT(%reg), %reg
+ // to
+ // lea foo@GOTOFF(%reg), %reg
+ // in Relocate::relocate, then there is nothing to do here.
+ if (reloc.get_r_offset() >= 2
+ && Target_i386::can_convert_mov_to_lea(gsym))
+ {
+ section_size_type stype;
+ const unsigned char* view = object->section_contents(data_shndx,
+ &stype, true);
+ if (view[reloc.get_r_offset() - 2] == 0x8b)
+ break;
+ }
+
if (gsym->final_value_is_known())
{
// For a STT_GNU_IFUNC symbol we want the PLT address.
break;
case elfcpp::R_386_GOTOFF:
+ // A GOT-relative reference must resolve locally.
+ if (!gsym->is_defined())
+ gold_error(_("%s: relocation R_386_GOTOFF against undefined symbol %s"
+ " cannot be used when making a shared object"),
+ object->name().c_str(), gsym->name());
+ else if (gsym->is_from_dynobj())
+ gold_error(_("%s: relocation R_386_GOTOFF against external symbol %s"
+ " cannot be used when making a shared object"),
+ object->name().c_str(), gsym->name());
+ else if (gsym->is_preemptible())
+ gold_error(_("%s: relocation R_386_GOTOFF against preemptible symbol %s"
+ " cannot be used when making a shared object"),
+ object->name().c_str(), gsym->name());
+ // We need a GOT section.
+ target->got_section(symtab, layout);
+ break;
+
case elfcpp::R_386_GOTPC:
// We need a GOT section.
target->got_section(symtab, layout);
size_t local_symbol_count,
const unsigned char* plocal_symbols)
{
- gold::gc_process_relocs<32, false, Target_i386, elfcpp::SHT_REL,
- Target_i386::Scan,
- Target_i386::Relocatable_size_for_reloc>(
+ gold::gc_process_relocs<32, false, Target_i386, Scan, Classify_reloc>(
symtab,
layout,
this,
return;
}
- gold::scan_relocs<32, false, Target_i386, elfcpp::SHT_REL,
- Target_i386::Scan>(
+ gold::scan_relocs<32, false, Target_i386, Scan, Classify_reloc>(
symtab,
layout,
this,
inline bool
Target_i386::Relocate::relocate(const Relocate_info<32, false>* relinfo,
- Target_i386* target,
- Output_section* output_section,
- size_t relnum,
- const elfcpp::Rel<32, false>& rel,
- unsigned int r_type,
- const Sized_symbol<32>* gsym,
- const Symbol_value<32>* psymval,
- unsigned char* view,
- elfcpp::Elf_types<32>::Elf_Addr address,
- section_size_type view_size)
+ unsigned int,
+ Target_i386* target,
+ Output_section* output_section,
+ size_t relnum,
+ const unsigned char* preloc,
+ const Sized_symbol<32>* gsym,
+ const Symbol_value<32>* psymval,
+ unsigned char* view,
+ elfcpp::Elf_types<32>::Elf_Addr address,
+ section_size_type view_size)
{
+ const elfcpp::Rel<32, false> rel(preloc);
+ unsigned int r_type = elfcpp::elf_r_type<32>(rel.get_r_info());
+
if (this->skip_call_tls_get_addr_)
{
if ((r_type != elfcpp::R_386_PLT32
+ && r_type != elfcpp::R_386_GOT32X
&& r_type != elfcpp::R_386_PC32)
|| gsym == NULL
|| strcmp(gsym->name(), "___tls_get_addr") != 0)
- gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
- _("missing expected TLS relocation"));
+ {
+ gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
+ _("missing expected TLS relocation"));
+ this->skip_call_tls_get_addr_ = false;
+ }
else
{
this->skip_call_tls_get_addr_ = false;
}
}
+ if (view == NULL)
+ return true;
+
const Sized_relobj_file<32, false>* object = relinfo->object;
// Pick the value to use for symbols defined in shared objects.
else if (gsym != NULL
&& gsym->use_plt_offset(Scan::get_reference_flags(r_type)))
{
- symval.set_output_value(target->plt_address_for_global(gsym)
- + gsym->plt_offset());
+ 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<32>(rel.get_r_info());
if (object->local_has_plt_offset(r_sym))
{
- symval.set_output_value(target->plt_address_for_local(object, r_sym)
- + object->local_plt_offset(r_sym));
+ symval.set_output_value(target->plt_address_for_local(object, r_sym));
psymval = &symval;
}
}
- // Get the GOT offset if needed.
- // The GOT pointer points to the end of the GOT section.
- // We need to subtract the size of the GOT section to get
- // the actual offset to use in the relocation.
- bool have_got_offset = false;
- unsigned int got_offset = 0;
- switch (r_type)
- {
- case elfcpp::R_386_GOT32:
- if (gsym != NULL)
- {
- gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
- got_offset = (gsym->got_offset(GOT_TYPE_STANDARD)
- - target->got_size());
- }
- else
- {
- unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.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)
- - target->got_size());
- }
- have_got_offset = true;
- break;
-
- default:
- break;
- }
+ bool baseless;
switch (r_type)
{
break;
case elfcpp::R_386_GOT32:
- gold_assert(have_got_offset);
- Relocate_functions<32, false>::rel32(view, got_offset);
+ case elfcpp::R_386_GOT32X:
+ baseless = (view[-1] & 0xc7) == 0x5;
+ // R_386_GOT32 and R_386_GOT32X don't work without base register
+ // when generating a position-independent output file.
+ if (baseless
+ && parameters->options().output_is_position_independent())
+ {
+ if(gsym)
+ gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
+ _("unexpected reloc %u against global symbol %s without base register in object file when generating a position-independent output file"),
+ r_type, gsym->demangled_name().c_str());
+ else
+ gold_error_at_location(relinfo, relnum, rel.get_r_offset(),
+ _("unexpected reloc %u against local symbol without base register in object file when generating a position-independent output file"),
+ r_type);
+ }
+
+ // Convert
+ // mov foo@GOT(%reg), %reg
+ // to
+ // lea foo@GOTOFF(%reg), %reg
+ // if possible.
+ if (rel.get_r_offset() >= 2
+ && view[-2] == 0x8b
+ && ((gsym == NULL && !psymval->is_ifunc_symbol())
+ || (gsym != NULL
+ && Target_i386::can_convert_mov_to_lea(gsym))))
+ {
+ view[-2] = 0x8d;
+ elfcpp::Elf_types<32>::Elf_Addr value;
+ value = psymval->value(object, 0);
+ // Don't subtract the .got.plt section address for baseless
+ // addressing.
+ if (!baseless)
+ value -= target->got_plt_section()->address();
+ Relocate_functions<32, false>::rel32(view, value);
+ }
+ else
+ {
+ // The GOT pointer points to the end of the GOT section.
+ // We need to subtract the size of the GOT section to get
+ // the actual offset to use in the relocation.
+ unsigned int got_offset = 0;
+ if (gsym != NULL)
+ {
+ gold_assert(gsym->has_got_offset(GOT_TYPE_STANDARD));
+ got_offset = (gsym->got_offset(GOT_TYPE_STANDARD)
+ - target->got_size());
+ }
+ else
+ {
+ unsigned int r_sym = elfcpp::elf_r_sym<32>(rel.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)
+ - target->got_size());
+ }
+ // Add the .got.plt section address for baseless addressing.
+ if (baseless)
+ got_offset += target->got_plt_section()->address();
+ Relocate_functions<32, false>::rel32(view, got_offset);
+ }
break;
case elfcpp::R_386_GOTOFF:
{
- elfcpp::Elf_types<32>::Elf_Addr value;
- value = (psymval->value(object, 0)
- - target->got_plt_section()->address());
- Relocate_functions<32, false>::rel32(view, value);
+ elfcpp::Elf_types<32>::Elf_Addr reladdr;
+ reladdr = target->got_plt_section()->address();
+ Relocate_functions<32, false>::pcrel32(view, object, psymval, reladdr);
}
break;
}
if (optimized_type == tls::TLSOPT_TO_IE)
{
- this->tls_gd_to_ie(relinfo, relnum, tls_segment, rel, r_type,
+ this->tls_gd_to_ie(relinfo, relnum, rel, r_type,
got_offset, view, view_size);
break;
}
}
if (optimized_type == tls::TLSOPT_TO_IE)
{
- if (tls_segment == NULL)
- {
- gold_assert(parameters->errors()->error_count() > 0
- || issue_undefined_symbol_error(gsym));
- return;
- }
- this->tls_desc_gd_to_ie(relinfo, relnum, tls_segment, rel, r_type,
+ this->tls_desc_gd_to_ie(relinfo, relnum, rel, r_type,
got_offset, view, view_size);
break;
}
unsigned char* view,
section_size_type view_size)
{
- // leal foo(,%reg,1),%eax; call ___tls_get_addr
+ // leal foo(,%ebx,1),%eax; call ___tls_get_addr@PLT
// ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
- // leal foo(%reg),%eax; call ___tls_get_addr
+ // leal foo(%ebx),%eax; call ___tls_get_addr@PLT
+ // ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
+ // leal foo(%reg),%eax; call *___tls_get_addr@GOT(%reg)
// ==> movl %gs:0,%eax; subl $foo@tpoff,%eax
tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
unsigned char op1 = view[-1];
unsigned char op2 = view[-2];
+ unsigned char op3 = view[4];
tls::check_tls(relinfo, relnum, rel.get_r_offset(),
op2 == 0x8d || op2 == 0x04);
- tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[4] == 0xe8);
+ tls::check_tls(relinfo, relnum, rel.get_r_offset(),
+ op3 == 0xe8 || op3 == 0xff);
int roff = 5;
}
else
{
+ unsigned char reg = op1 & 7;
tls::check_tls(relinfo, relnum, rel.get_r_offset(),
- (op1 & 0xf8) == 0x80 && (op1 & 7) != 4);
- if (rel.get_r_offset() + 9 < view_size
- && view[9] == 0x90)
+ ((op1 & 0xf8) == 0x80
+ && reg != 4
+ && reg != 0
+ && (op3 == 0xe8 || (view[5] & 0x7) == reg)));
+ if (op3 == 0xff
+ || (rel.get_r_offset() + 9 < view_size
+ && view[9] == 0x90))
{
- // There is a trailing nop. Use the size byte subl.
+ // There is an indirect call or a trailing nop. Use the size
+ // byte subl.
memcpy(view - 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
roff = 6;
}
inline void
Target_i386::Relocate::tls_gd_to_ie(const Relocate_info<32, false>* relinfo,
size_t relnum,
- Output_segment*,
const elfcpp::Rel<32, false>& rel,
unsigned int,
elfcpp::Elf_types<32>::Elf_Addr value,
unsigned char* view,
section_size_type view_size)
{
- // leal foo(,%ebx,1),%eax; call ___tls_get_addr
+ // leal foo(,%ebx,1),%eax; call ___tls_get_addr@PLT
// ==> movl %gs:0,%eax; addl foo@gotntpoff(%ebx),%eax
+ // leal foo(%ebx),%eax; call ___tls_get_addr@PLT; nop
+ // ==> movl %gs:0,%eax; addl foo@gotntpoff(%ebx),%eax
+ // leal foo(%reg),%eax; call *___tls_get_addr@GOT(%reg)
+ // ==> movl %gs:0,%eax; addl foo@gotntpoff(%reg),%eax
tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 9);
unsigned char op1 = view[-1];
unsigned char op2 = view[-2];
+ unsigned char op3 = view[4];
tls::check_tls(relinfo, relnum, rel.get_r_offset(),
op2 == 0x8d || op2 == 0x04);
- tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[4] == 0xe8);
-
- int roff = 5;
+ tls::check_tls(relinfo, relnum, rel.get_r_offset(),
+ op3 == 0xe8 || op3 == 0xff);
- // FIXME: For now, support only the first (SIB) form.
- tls::check_tls(relinfo, relnum, rel.get_r_offset(), op2 == 0x04);
+ int roff;
if (op2 == 0x04)
{
tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[-3] == 0x8d);
tls::check_tls(relinfo, relnum, rel.get_r_offset(),
((op1 & 0xc7) == 0x05 && op1 != (4 << 3)));
- memcpy(view - 3, "\x65\xa1\0\0\0\0\x03\x83\0\0\0", 12);
+ roff = 5;
}
else
{
+ unsigned char reg = op1 & 7;
+ tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 10);
tls::check_tls(relinfo, relnum, rel.get_r_offset(),
- (op1 & 0xf8) == 0x80 && (op1 & 7) != 4);
- if (rel.get_r_offset() + 9 < view_size
- && view[9] == 0x90)
- {
- // FIXME: This is not the right instruction sequence.
- // There is a trailing nop. Use the size byte subl.
- memcpy(view - 2, "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
- roff = 6;
- }
- else
- {
- // FIXME: This is not the right instruction sequence.
- // Use the five byte subl.
- memcpy(view - 2, "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
- }
+ ((op1 & 0xf8) == 0x80
+ && reg != 4
+ && reg != 0
+ && ((op3 == 0xe8 && view[9] == 0x90)
+ || (view[5] & 0x7) == reg)));
+ roff = 6;
}
+ memcpy(view + roff - 8, "\x65\xa1\0\0\0\0\x03\x83\0\0\0", 12);
Relocate_functions<32, false>::rel32(view + roff, value);
// The next reloc should be a PLT32 reloc against __tls_get_addr.
Target_i386::Relocate::tls_desc_gd_to_ie(
const Relocate_info<32, false>* relinfo,
size_t relnum,
- Output_segment*,
const elfcpp::Rel<32, false>& rel,
unsigned int r_type,
elfcpp::Elf_types<32>::Elf_Addr value,
unsigned char* view,
section_size_type view_size)
{
- // leal foo(%reg), %eax; call ___tls_get_addr
+ // leal foo(%ebx), %eax; call ___tls_get_addr@PLT
// ==> movl %gs:0,%eax; nop; leal 0(%esi,1),%esi
+ // leal foo(%reg), %eax; call call *___tls_get_addr@GOT(%reg)
+ // ==> movl %gs:0,%eax; leal (%esi),%esi
tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, -2);
- tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size, 9);
- // FIXME: Does this test really always pass?
+ unsigned char op1 = view[-1];
+ unsigned char op2 = view[-2];
+ unsigned char op3 = view[4];
+
tls::check_tls(relinfo, relnum, rel.get_r_offset(),
- view[-2] == 0x8d && view[-1] == 0x83);
+ op3 == 0xe8 || op3 == 0xff);
+ tls::check_range(relinfo, relnum, rel.get_r_offset(), view_size,
+ op3 == 0xe8 ? 9 : 10);
- tls::check_tls(relinfo, relnum, rel.get_r_offset(), view[4] == 0xe8);
+ // FIXME: Does this test really always pass?
+ tls::check_tls(relinfo, relnum, rel.get_r_offset(), op2 == 0x8d);
- memcpy(view - 2, "\x65\xa1\0\0\0\0\x90\x8d\x74\x26\0", 11);
+ unsigned char reg = op1 & 7;
+ tls::check_tls(relinfo, relnum, rel.get_r_offset(),
+ ((op1 & 0xf8) == 0x80
+ && reg != 4
+ && reg != 0
+ && (op3 == 0xe8 || (view[5] & 0x7) == reg)));
+
+ if (op3 == 0xe8)
+ memcpy(view - 2, "\x65\xa1\0\0\0\0\x90\x8d\x74\x26\0", 11);
+ else
+ memcpy(view - 2, "\x65\xa1\0\0\0\0\x8d\xb6\0\0\0\0", 12);
// The next reloc should be a PLT32 reloc against __tls_get_addr.
// We can skip it.
{
gold_assert(sh_type == elfcpp::SHT_REL);
- gold::relocate_section<32, false, Target_i386, elfcpp::SHT_REL,
- Target_i386::Relocate>(
+ gold::relocate_section<32, false, Target_i386, Relocate,
+ gold::Default_comdat_behavior, Classify_reloc>(
relinfo,
this,
prelocs,
// link.
unsigned int
-Target_i386::Relocatable_size_for_reloc::get_size_for_reloc(
+Target_i386::Classify_reloc::get_size_for_reloc(
unsigned int r_type,
Relobj* object)
{
case elfcpp::R_386_32:
case elfcpp::R_386_PC32:
case elfcpp::R_386_GOT32:
+ case elfcpp::R_386_GOT32X:
case elfcpp::R_386_PLT32:
case elfcpp::R_386_GOTOFF:
case elfcpp::R_386_GOTPC:
const unsigned char* plocal_symbols,
Relocatable_relocs* rr)
{
- gold_assert(sh_type == elfcpp::SHT_REL);
+ typedef gold::Default_scan_relocatable_relocs<Classify_reloc>
+ Scan_relocatable_relocs;
- typedef gold::Default_scan_relocatable_relocs<elfcpp::SHT_REL,
- Relocatable_size_for_reloc> Scan_relocatable_relocs;
+ gold_assert(sh_type == elfcpp::SHT_REL);
- gold::scan_relocatable_relocs<32, false, elfcpp::SHT_REL,
- Scan_relocatable_relocs>(
+ gold::scan_relocatable_relocs<32, false, Scan_relocatable_relocs>(
symtab,
layout,
object,
rr);
}
-// Relocate a section during a relocatable link.
+// Scan the relocs for --emit-relocs.
+
+void
+Target_i386::emit_relocs_scan(Symbol_table* symtab,
+ Layout* layout,
+ Sized_relobj_file<32, false>* 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, false>
+ 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, false, 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.
void
-Target_i386::relocate_for_relocatable(
+Target_i386::relocate_relocs(
const Relocate_info<32, false>* relinfo,
unsigned int sh_type,
const unsigned char* prelocs,
size_t reloc_count,
Output_section* output_section,
- off_t offset_in_output_section,
- const Relocatable_relocs* rr,
+ elfcpp::Elf_types<32>::Elf_Off offset_in_output_section,
unsigned char* view,
elfcpp::Elf_types<32>::Elf_Addr view_address,
section_size_type view_size,
{
gold_assert(sh_type == elfcpp::SHT_REL);
- gold::relocate_for_relocatable<32, false, elfcpp::SHT_REL>(
+ gold::relocate_relocs<32, false, Classify_reloc>(
relinfo,
prelocs,
reloc_count,
output_section,
offset_in_output_section,
- rr,
view,
view_address,
view_size,
Target_i386::do_dynsym_value(const Symbol* gsym) const
{
gold_assert(gsym->is_from_dynobj() && gsym->has_plt_offset());
- return this->plt_address_for_global(gsym) + gsym->plt_offset();
+ return this->plt_address_for_global(gsym);
}
// Return a string used to fill a code section with nops to take up
// get_pc_thunk function.
bool
-Target_i386::do_is_call_to_non_split(const Symbol* sym, unsigned int) const
+Target_i386::do_is_call_to_non_split(const Symbol* sym,
+ const unsigned char*,
+ const unsigned char*,
+ section_size_type) const
{
return (sym->type() == elfcpp::STT_FUNC
&& !is_prefix_of("__i686.get_pc_thunk.", sym->name()));
Target_i386::do_calls_non_split(Relobj* object, unsigned int shndx,
section_offset_type fnoffset,
section_size_type fnsize,
+ const unsigned char*,
+ size_t,
unsigned char* view,
section_size_type view_size,
std::string* from,
{
public:
Output_data_plt_i386_nacl(Layout* layout,
- Output_data_space* got_plt,
+ Output_data_got_plt_i386* got_plt,
Output_data_space* got_irelative)
: Output_data_plt_i386(layout, plt_entry_size, got_plt, got_irelative)
{ }
{
public:
Output_data_plt_i386_nacl_exec(Layout* layout,
- Output_data_space* got_plt,
+ Output_data_got_plt_i386* got_plt,
Output_data_space* got_irelative)
: Output_data_plt_i386_nacl(layout, got_plt, got_irelative)
{ }
{
public:
Output_data_plt_i386_nacl_dyn(Layout* layout,
- Output_data_space* got_plt,
+ Output_data_got_plt_i386* got_plt,
Output_data_space* got_irelative)
: Output_data_plt_i386_nacl(layout, got_plt, got_irelative)
{ }
protected:
virtual Output_data_plt_i386*
do_make_data_plt(Layout* layout,
- Output_data_space* got_plt,
+ Output_data_got_plt_i386* got_plt,
Output_data_space* got_irelative,
bool dyn)
{
return new Output_data_plt_i386_nacl_exec(layout, got_plt, got_irelative);
}
+ virtual std::string
+ do_code_fill(section_size_type length) const;
+
private:
static const Target::Target_info i386_nacl_info;
};
0, // small_common_section_flags
0, // large_common_section_flags
NULL, // attributes_section
- NULL // attributes_vendor
+ NULL, // attributes_vendor
+ "_start", // entry_symbol_name
+ 32, // hash_entry_size
+ elfcpp::SHT_PROGBITS, // unwind_section_type
};
#define NACLMASK 0xe0 // 32-byte alignment mask
elfcpp::DW_CFA_nop
};
+// Return a string used to fill a code section with nops.
+// For NaCl, long NOPs are only valid if they do not cross
+// bundle alignment boundaries, so keep it simple with one-byte NOPs.
+std::string
+Target_i386_nacl::do_code_fill(section_size_type length) const
+{
+ return std::string(length, static_cast<char>(0x90));
+}
+
// The selector for i386-nacl object files.
class Target_selector_i386_nacl
Target_selector_i386_nacl target_selector_i386;
+// IAMCU variant. It uses EM_IAMCU, not EM_386.
+
+class Target_iamcu : public Target_i386
+{
+ public:
+ Target_iamcu()
+ : Target_i386(&iamcu_info)
+ { }
+
+ private:
+ // Information about this specific target which we pass to the
+ // general Target structure.
+ static const Target::Target_info iamcu_info;
+};
+
+const Target::Target_info Target_iamcu::iamcu_info =
+{
+ 32, // size
+ false, // is_big_endian
+ elfcpp::EM_IAMCU, // machine_code
+ false, // has_make_symbol
+ false, // has_resolve
+ true, // has_code_fill
+ true, // is_default_stack_executable
+ true, // can_icf_inline_merge_sections
+ '\0', // wrap_char
+ "/usr/lib/libc.so.1", // dynamic_linker
+ 0x08048000, // default_text_segment_address
+ 0x1000, // 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
+ elfcpp::SHT_PROGBITS, // unwind_section_type
+};
+
+class Target_selector_iamcu : public Target_selector
+{
+public:
+ Target_selector_iamcu()
+ : Target_selector(elfcpp::EM_IAMCU, 32, false, "elf32-iamcu",
+ "elf_iamcu")
+ { }
+
+ Target*
+ do_instantiate_target()
+ { return new Target_iamcu(); }
+};
+
+Target_selector_iamcu target_selector_iamcu;
+
} // End anonymous namespace.