Add support for STT_SPARC_REGISTER symbols.

gold/
	PR gold/19019
	* layout.h (Layout::add_target_specific_dynamic_tag): New function.
	* layout.cc (Layout::add_target_specific_dynamic_tag): New function.
	* mips.cc (Target_mips::make_symbol): Adjust function signature.
	* sparc.cc (Target_sparc::Target_sparc): Initialize register_syms_.
	(Target_sparc::do_is_defined_by_abi): Remove test for
	STT_SPARC_REGISTER.
	(Target_sparc::Register_symbol): New struct type.
	(Target_sparc::register_syms_): New data member.
	(Target_sparc<64, true>::sparc_info): Set has_make_symbol to true.
	(Target_sparc::make_symbol): New function.
	(Target_sparc::do_finalize_sections): Add register symbols and new
	dynamic table entries.
	* symtab.h (Sized_symbol::init_undefined): Add value parameter.
	(Symbol_table::add_target_global_symbol): New function.
	(Symbol_table::target_symbols_): New data member.
	* symtab.cc (Sized_symbol::init_undefined): Add value parameter.
	(Symbol_table::Symbol_table): Initialize target_symbols_.
	(Symbol_table::add_from_object): Pass additional parameters to
	Target::make_symbol.
	(Symbol_table::define_special_symbol): Likewise.
	(Symbol_table::add_undefined_symbol_from_command_line): Pass 0 for
	undefined symbol value.
	(Symbol_table::set_dynsym_indexes): Process target-specific symbols.
	(Symbol_table::sized_finalize): Likewise.
	(Symbol_table::sized_write_globals): Likewise.
	* target.h (Sized_target::make_symbol): Add name, st_type, object,
	st_shndx, and value parameters.
This commit is contained in:
Cary Coutant 2016-02-04 16:55:39 -08:00
parent 8b4ee0a5c1
commit dc1c8a16a3
8 changed files with 236 additions and 20 deletions

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@ -1,3 +1,34 @@
2016-03-03 Cary Coutant <ccoutant@gmail.com>
PR gold/19019
* layout.h (Layout::add_target_specific_dynamic_tag): New function.
* layout.cc (Layout::add_target_specific_dynamic_tag): New function.
* mips.cc (Target_mips::make_symbol): Adjust function signature.
* sparc.cc (Target_sparc::Target_sparc): Initialize register_syms_.
(Target_sparc::do_is_defined_by_abi): Remove test for
STT_SPARC_REGISTER.
(Target_sparc::Register_symbol): New struct type.
(Target_sparc::register_syms_): New data member.
(Target_sparc<64, true>::sparc_info): Set has_make_symbol to true.
(Target_sparc::make_symbol): New function.
(Target_sparc::do_finalize_sections): Add register symbols and new
dynamic table entries.
* symtab.h (Sized_symbol::init_undefined): Add value parameter.
(Symbol_table::add_target_global_symbol): New function.
(Symbol_table::target_symbols_): New data member.
* symtab.cc (Sized_symbol::init_undefined): Add value parameter.
(Symbol_table::Symbol_table): Initialize target_symbols_.
(Symbol_table::add_from_object): Pass additional parameters to
Target::make_symbol.
(Symbol_table::define_special_symbol): Likewise.
(Symbol_table::add_undefined_symbol_from_command_line): Pass 0 for
undefined symbol value.
(Symbol_table::set_dynsym_indexes): Process target-specific symbols.
(Symbol_table::sized_finalize): Likewise.
(Symbol_table::sized_write_globals): Likewise.
* target.h (Sized_target::make_symbol): Add name, st_type, object,
st_shndx, and value parameters.
2015-03-03 Rafael Ávila de Espíndola <rafael.espindola@gmail.com>
* plugin.cc (do_should_include_member): Ignore LDPK_UNDEF and

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@ -4724,6 +4724,15 @@ Layout::add_target_dynamic_tags(bool use_rel, const Output_data* plt_got,
}
}
void
Layout::add_target_specific_dynamic_tag(elfcpp::DT tag, unsigned int val)
{
Output_data_dynamic* odyn = this->dynamic_data_;
if (odyn == NULL)
return;
odyn->add_constant(tag, val);
}
// Finish the .dynamic section and PT_DYNAMIC segment.
void

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@ -902,6 +902,10 @@ class Layout
const Output_data_reloc_generic* dyn_rel,
bool add_debug, bool dynrel_includes_plt);
// Add a target-specific dynamic tag with constant value.
void
add_target_specific_dynamic_tag(elfcpp::DT tag, unsigned int val);
// Compute and write out the build ID if needed.
void
write_build_id(Output_file*, unsigned char*, size_t) const;

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@ -3079,7 +3079,7 @@ class Target_mips : public Sized_target<size, big_endian>
// Make a new symbol table entry for the Mips target.
Sized_symbol<size>*
make_symbol() const
make_symbol(const char*, elfcpp::STT, Object*, unsigned int, uint64_t)
{ return new Mips_symbol<size>(); }
// Process the relocations to determine unreferenced sections for

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@ -62,10 +62,14 @@ class Target_sparc : public Sized_target<size, big_endian>
copy_relocs_(elfcpp::R_SPARC_COPY),
got_mod_index_offset_(-1U), tls_get_addr_sym_(NULL),
elf_machine_(sparc_info.machine_code), elf_flags_(0),
elf_flags_set_(false)
elf_flags_set_(false), register_syms_()
{
}
// Make a new symbol table entry.
Sized_symbol<size>*
make_symbol(const char*, elfcpp::STT, Object*, unsigned int, uint64_t);
// Process the relocations to determine unreferenced sections for
// garbage collection.
void
@ -164,13 +168,7 @@ class Target_sparc : public Sized_target<size, big_endian>
// Return whether SYM is defined by the ABI.
bool
do_is_defined_by_abi(const Symbol* sym) const
{
// XXX Really need to support this better...
if (sym->type() == elfcpp::STT_SPARC_REGISTER)
return 1;
return strcmp(sym->name(), "___tls_get_addr") == 0;
}
{ return strcmp(sym->name(), "___tls_get_addr") == 0; }
// Return the PLT address to use for a global symbol.
uint64_t
@ -441,6 +439,16 @@ class Target_sparc : public Sized_target<size, big_endian>
GOT_TYPE_TLS_PAIR = 2, // GOT entry for TLS module/offset pair
};
struct Register_symbol
{
Register_symbol()
: name(NULL), shndx(0), obj(NULL)
{ }
const char* name;
unsigned int shndx;
Object* obj;
};
// The GOT section.
Output_data_got<size, big_endian>* got_;
// The PLT section.
@ -461,6 +469,8 @@ class Target_sparc : public Sized_target<size, big_endian>
elfcpp::Elf_Word elf_flags_;
// Whether elf_flags_ has been set for the first time yet
bool elf_flags_set_;
// STT_SPARC_REGISTER symbols (%g2, %g3, %g6, %g7).
Register_symbol register_syms_[4];
};
template<>
@ -497,7 +507,7 @@ Target::Target_info Target_sparc<64, true>::sparc_info =
64, // size
true, // is_big_endian
elfcpp::EM_SPARCV9, // machine_code
false, // has_make_symbol
true, // has_make_symbol
false, // has_resolve
false, // has_code_fill
true, // is_default_stack_executable
@ -3023,6 +3033,68 @@ Target_sparc<size, big_endian>::Scan::global(
}
}
// Make a new symbol table entry.
// STT_SPARC_REGISTER symbols require special handling,
// so we intercept these symbols and keep track of them separately.
// We will resolve register symbols here and output them at symbol
// finalization time.
template<int size, bool big_endian>
Sized_symbol<size>*
Target_sparc<size, big_endian>::make_symbol(const char* name,
elfcpp::STT type,
Object* object,
unsigned int shndx,
uint64_t value)
{
// REGISTER symbols are used only on SPARC-64.
if (size == 64 && type == elfcpp::STT_SPARC_REGISTER)
{
// Ignore REGISTER symbols in dynamic objects.
if (object->is_dynamic())
return NULL;
// Only registers 2, 3, 6, and 7 can be declared global.
int reg = value;
switch (reg)
{
case 2: case 3:
reg -= 2;
break;
case 6: case 7:
reg -= 4;
break;
default:
gold_error(_("%s: only registers %%g[2367] can be declared "
"using STT_REGISTER"),
object->name().c_str());
return NULL;
}
Register_symbol& rsym = this->register_syms_[reg];
if (rsym.name == NULL)
{
rsym.name = name;
rsym.shndx = shndx;
rsym.obj = object;
}
else
{
if (strcmp(rsym.name, name) != 0)
{
gold_error(_("%s: register %%g%d declared as '%s'; "
"previously declared as '%s' in %s"),
object->name().c_str(),
static_cast<int>(value),
*name ? name : "#scratch",
*rsym.name ? rsym.name : "#scratch",
rsym.obj->name().c_str());
return NULL;
}
}
return NULL;
}
return new Sized_symbol<size>();
}
// Process relocations for gc.
template<int size, bool big_endian>
@ -3165,6 +3237,27 @@ Target_sparc<size, big_endian>::do_finalize_sections(
symtab->define_symbols(layout, 2, syms,
layout->script_options()->saw_sections_clause());
}
for (int reg = 0; reg < 4; ++reg)
{
Register_symbol& rsym = this->register_syms_[reg];
if (rsym.name != NULL)
{
int value = reg < 3 ? reg + 2 : reg + 4;
Sized_symbol<size>* sym = new Sized_symbol<size>();
if (rsym.shndx == elfcpp::SHN_UNDEF)
sym->init_undefined(rsym.name, NULL, value,
elfcpp::STT_SPARC_REGISTER, elfcpp::STB_GLOBAL,
elfcpp::STV_DEFAULT, 0);
else
sym->init_constant(rsym.name, NULL, value, 0,
elfcpp::STT_SPARC_REGISTER, elfcpp::STB_GLOBAL,
elfcpp::STV_DEFAULT, 0, false);
symtab->add_target_global_symbol(sym);
layout->add_target_specific_dynamic_tag(elfcpp::DT_SPARC_REGISTER,
value);
}
}
}
// Perform a relocation.

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@ -285,11 +285,12 @@ Sized_symbol<size>::init_constant(const char* name, const char* version,
template<int size>
void
Sized_symbol<size>::init_undefined(const char* name, const char* version,
elfcpp::STT type, elfcpp::STB binding,
elfcpp::STV visibility, unsigned char nonvis)
Value_type value, elfcpp::STT type,
elfcpp::STB binding, elfcpp::STV visibility,
unsigned char nonvis)
{
this->init_base_undefined(name, version, type, binding, visibility, nonvis);
this->value_ = 0;
this->value_ = value;
this->symsize_ = 0;
}
@ -565,7 +566,8 @@ Symbol_table::Symbol_table(unsigned int count,
: saw_undefined_(0), offset_(0), table_(count), namepool_(),
forwarders_(), commons_(), tls_commons_(), small_commons_(),
large_commons_(), forced_locals_(), warnings_(),
version_script_(version_script), gc_(NULL), icf_(NULL)
version_script_(version_script), gc_(NULL), icf_(NULL),
target_symbols_()
{
namepool_.reserve(count);
}
@ -1058,7 +1060,8 @@ Symbol_table::add_from_object(Object* object,
ret = new Sized_symbol<size>();
else
{
ret = target->make_symbol();
ret = target->make_symbol(name, sym.get_st_type(), object,
st_shndx, sym.get_st_value());
if (ret == NULL)
{
// This means that we don't want a symbol table
@ -1858,7 +1861,8 @@ Symbol_table::define_special_symbol(const char** pname, const char** pversion,
{
Sized_target<size, big_endian>* sized_target =
parameters->sized_target<size, big_endian>();
sym = sized_target->make_symbol();
sym = sized_target->make_symbol(*pname, elfcpp::STT_NOTYPE,
NULL, elfcpp::SHN_UNDEF, 0);
if (sym == NULL)
return NULL;
}
@ -2437,7 +2441,7 @@ Symbol_table::add_undefined_symbol_from_command_line(const char* name)
gold_assert(oldsym == NULL);
sym->init_undefined(name, version, elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL,
sym->init_undefined(name, version, 0, elfcpp::STT_NOTYPE, elfcpp::STB_GLOBAL,
elfcpp::STV_DEFAULT, 0);
++this->saw_undefined_;
}
@ -2534,6 +2538,17 @@ Symbol_table::set_dynsym_indexes(unsigned int index,
// symbols.
index = versions->finalize(this, index, syms);
// Process target-specific symbols.
for (std::vector<Symbol*>::iterator p = this->target_symbols_.begin();
p != this->target_symbols_.end();
++p)
{
(*p)->set_dynsym_index(index);
++index;
syms->push_back(*p);
dynpool->add((*p)->name(), false, NULL);
}
return index;
}
@ -2639,6 +2654,14 @@ Symbol_table::sized_finalize(off_t off, Stringpool* pool,
this->add_to_final_symtab<size>(sym, pool, &index, &off);
}
// Now do target-specific symbols.
for (std::vector<Symbol*>::iterator p = this->target_symbols_.begin();
p != this->target_symbols_.end();
++p)
{
this->add_to_final_symtab<size>(*p, pool, &index, &off);
}
this->output_count_ = index - orig_index;
return off;
@ -3108,6 +3131,54 @@ Symbol_table::sized_write_globals(const Stringpool* sympool,
}
}
// Write the target-specific symbols.
for (std::vector<Symbol*>::const_iterator p = this->target_symbols_.begin();
p != this->target_symbols_.end();
++p)
{
Sized_symbol<size>* sym = static_cast<Sized_symbol<size>*>(*p);
unsigned int sym_index = sym->symtab_index();
unsigned int dynsym_index;
if (dynamic_view == NULL)
dynsym_index = -1U;
else
dynsym_index = sym->dynsym_index();
unsigned int shndx;
switch (sym->source())
{
case Symbol::IS_CONSTANT:
shndx = elfcpp::SHN_ABS;
break;
case Symbol::IS_UNDEFINED:
shndx = elfcpp::SHN_UNDEF;
break;
default:
gold_unreachable();
}
if (sym_index != -1U)
{
sym_index -= first_global_index;
gold_assert(sym_index < output_count);
unsigned char* ps = psyms + (sym_index * sym_size);
this->sized_write_symbol<size, big_endian>(sym, sym->value(), shndx,
sym->binding(), sympool,
ps);
}
if (dynsym_index != -1U)
{
dynsym_index -= first_dynamic_global_index;
gold_assert(dynsym_index < dynamic_count);
unsigned char* pd = dynamic_view + (dynsym_index * sym_size);
this->sized_write_symbol<size, big_endian>(sym, sym->value(), shndx,
sym->binding(), dynpool,
pd);
}
}
of->write_output_view(this->offset_, oview_size, psyms);
if (dynamic_view != NULL)
of->write_output_view(this->dynamic_offset_, dynamic_size, dynamic_view);

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@ -1113,8 +1113,8 @@ class Sized_symbol : public Symbol
// Initialize fields for an undefined symbol.
void
init_undefined(const char* name, const char* version, elfcpp::STT,
elfcpp::STB, elfcpp::STV, unsigned char nonvis);
init_undefined(const char* name, const char* version, Value_type value,
elfcpp::STT, elfcpp::STB, elfcpp::STV, unsigned char nonvis);
// Override existing symbol.
template<bool big_endian>
@ -1481,6 +1481,12 @@ class Symbol_table
define_symbols(const Layout*, int count, const Define_symbol_in_segment*,
bool only_if_ref);
// Add a target-specific global symbol.
// (Used by SPARC backend to add STT_SPARC_REGISTER symbols.)
void
add_target_global_symbol(Symbol* sym)
{ this->target_symbols_.push_back(sym); }
// Define SYM using a COPY reloc. POSD is the Output_data where the
// symbol should be defined--typically a .dyn.bss section. VALUE is
// the offset within POSD.
@ -1951,6 +1957,8 @@ class Symbol_table
const Version_script_info& version_script_;
Garbage_collection* gc_;
Icf* icf_;
// Target-specific symbols, if any.
std::vector<Symbol*> target_symbols_;
};
// We inline get_sized_symbol for efficiency.

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@ -834,7 +834,7 @@ class Sized_target : public Target
// symbol table. This will only be called if has_make_symbol()
// returns true.
virtual Sized_symbol<size>*
make_symbol() const
make_symbol(const char*, elfcpp::STT, Object*, unsigned int, uint64_t)
{ gold_unreachable(); }
// Resolve a symbol for the target. This should be overridden by a