diff options
Diffstat (limited to 'gold/powerpc.cc')
-rw-r--r-- | gold/powerpc.cc | 153 |
1 files changed, 147 insertions, 6 deletions
diff --git a/gold/powerpc.cc b/gold/powerpc.cc index 9ac81a1..f9a14ce 100644 --- a/gold/powerpc.cc +++ b/gold/powerpc.cc @@ -59,11 +59,14 @@ class Powerpc_relobj : public Sized_relobj_file<size, big_endian> public: typedef typename elfcpp::Elf_types<size>::Elf_Addr Address; typedef typename elfcpp::Elf_types<size>::Elf_Off Offset; + typedef Unordered_set<Section_id, Section_id_hash> Section_refs; + typedef Unordered_map<Address, Section_refs> Access_from; Powerpc_relobj(const std::string& name, Input_file* input_file, off_t offset, const typename elfcpp::Ehdr<size, big_endian>& ehdr) : Sized_relobj_file<size, big_endian>(name, input_file, offset, ehdr), - special_(0), opd_ent_shndx_(), opd_ent_off_() + special_(0), opd_ent_shndx_(), opd_ent_off_(), access_from_map_(), + opd_valid_(false) { } ~Powerpc_relobj() @@ -99,14 +102,15 @@ public: } // Return section and offset of function entry for .opd + R_OFF. - void - get_opd_ent(Address r_off, unsigned int* shndx, Address* value) const + unsigned int + get_opd_ent(Address r_off, Address* value = NULL) const { size_t ndx = this->opd_ent_ndx(r_off); gold_assert(ndx < this->opd_ent_shndx_.size()); gold_assert(this->opd_ent_shndx_[ndx] != 0); - *shndx = this->opd_ent_shndx_[ndx]; - *value = this->opd_ent_off_[ndx]; + if (value != NULL) + *value = this->opd_ent_off_[ndx]; + return this->opd_ent_shndx_[ndx]; } // Set section and offset of function entry for .opd + R_OFF. @@ -119,6 +123,29 @@ public: this->opd_ent_off_[ndx] = value; } + Access_from* + access_from_map() + { return &this->access_from_map_; } + + // Add a reference from SRC_OBJ, SRC_INDX to this object's .opd + // section at DST_OFF. + void + add_reference(Object* src_obj, + unsigned int src_indx, + typename elfcpp::Elf_types<size>::Elf_Addr dst_off) + { + Section_id src_id(src_obj, src_indx); + this->access_from_map_[dst_off].insert(src_id); + } + + bool + opd_valid() const + { return this->opd_valid_; } + + void + set_opd_valid() + { this->opd_valid_ = true; } + // Examine .rela.opd to build info about function entry points. void scan_opd_relocs(size_t reloc_count, @@ -160,6 +187,16 @@ private: // section and offset specified by these relocations. std::vector<unsigned int> opd_ent_shndx_; std::vector<Offset> opd_ent_off_; + // References made to this object's .opd section when running + // gc_process_relocs for another object, before the opd_ent vectors + // are valid for this object. + Access_from access_from_map_; + // Set at the start of gc_process_relocs, when we know opd_ent + // vectors are valid. The flag could be made atomic and set in + // do_read_relocs with memory_order_release and then tested with + // memory_order_acquire, potentially resulting in fewer entries in + // access_from_map_. + bool opd_valid_; }; template<int size, bool big_endian> @@ -340,6 +377,24 @@ class Target_powerpc : public Sized_target<size, big_endian> unsigned int plt_entry_size() const; + // Add any special sections for this symbol to the gc work list. + // For powerpc64, this adds the code section of a function + // descriptor. + void + do_gc_mark_symbol(Symbol_table* symtab, Symbol* sym) const; + + // Handle target specific gc actions when adding a gc reference from + // SRC_OBJ, SRC_SHNDX to a location specified by DST_OBJ, DST_SHNDX + // and DST_OFF. For powerpc64, this adds a referenc to the code + // section of a function descriptor. + void + do_gc_add_reference(Symbol_table* symtab, + Object* src_obj, + unsigned int src_shndx, + Object* dst_obj, + unsigned int dst_shndx, + Address dst_off) const; + private: // The class which scans relocations. @@ -2913,6 +2968,33 @@ Target_powerpc<size, big_endian>::gc_process_relocs( { typedef Target_powerpc<size, big_endian> Powerpc; typedef typename Target_powerpc<size, big_endian>::Scan Scan; + Powerpc_relobj<size, big_endian>* ppc_object + = static_cast<Powerpc_relobj<size, big_endian>*>(object); + if (size == 64) + ppc_object->set_opd_valid(); + if (size == 64 && data_shndx == ppc_object->opd_shndx()) + { + typename Powerpc_relobj<size, big_endian>::Access_from::iterator p; + for (p = ppc_object->access_from_map()->begin(); + p != ppc_object->access_from_map()->end(); + ++p) + { + Address dst_off = p->first; + unsigned int dst_indx = ppc_object->get_opd_ent(dst_off); + typename Powerpc_relobj<size, big_endian>::Section_refs::iterator s; + for (s = p->second.begin(); s != p->second.end(); ++s) + { + Object* src_obj = s->first; + unsigned int src_indx = s->second; + symtab->gc()->add_reference(src_obj, src_indx, + ppc_object, dst_indx); + } + p->second.clear(); + } + ppc_object->access_from_map()->clear(); + // Don't look at .opd relocs as .opd will reference everything. + return; + } gold::gc_process_relocs<size, big_endian, Powerpc, elfcpp::SHT_RELA, Scan, typename Target_powerpc::Relocatable_size_for_reloc>( @@ -2929,6 +3011,65 @@ Target_powerpc<size, big_endian>::gc_process_relocs( plocal_symbols); } +// Handle target specific gc actions when adding a gc reference from +// SRC_OBJ, SRC_SHNDX to a location specified by DST_OBJ, DST_SHNDX +// and DST_OFF. For powerpc64, this adds a referenc to the code +// section of a function descriptor. + +template<int size, bool big_endian> +void +Target_powerpc<size, big_endian>::do_gc_add_reference( + Symbol_table* symtab, + Object* src_obj, + unsigned int src_shndx, + Object* dst_obj, + unsigned int dst_shndx, + Address dst_off) const +{ + Powerpc_relobj<size, big_endian>* ppc_object + = static_cast<Powerpc_relobj<size, big_endian>*>(dst_obj); + if (size == 64 && dst_shndx == ppc_object->opd_shndx()) + { + if (ppc_object->opd_valid()) + { + dst_shndx = ppc_object->get_opd_ent(dst_off); + symtab->gc()->add_reference(src_obj, src_shndx, dst_obj, dst_shndx); + } + else + { + // If we haven't run scan_opd_relocs, we must delay + // processing this function descriptor reference. + ppc_object->add_reference(src_obj, src_shndx, dst_off); + } + } +} + +// Add any special sections for this symbol to the gc work list. +// For powerpc64, this adds the code section of a function +// descriptor. + +template<int size, bool big_endian> +void +Target_powerpc<size, big_endian>::do_gc_mark_symbol( + Symbol_table* symtab, + Symbol* sym) const +{ + if (size == 64) + { + Powerpc_relobj<size, big_endian>* ppc_object + = static_cast<Powerpc_relobj<size, big_endian>*>(sym->object()); + bool is_ordinary; + unsigned int shndx = sym->shndx(&is_ordinary); + if (is_ordinary && shndx == ppc_object->opd_shndx()) + { + Sized_symbol<size>* gsym = symtab->get_sized_symbol<size>(sym); + Address dst_off = gsym->value(); + unsigned int dst_indx = ppc_object->get_opd_ent(dst_off); + symtab->gc()->worklist().push(Section_id(ppc_object, dst_indx)); + } + } +} + // Scan relocations for a section. template<int size, bool big_endian> @@ -3064,7 +3205,7 @@ Target_powerpc<size, big_endian>::symval_for_branch( if (value >= opd_addr && value < opd_addr + symobj->section_size(shndx)) { Address sec_off; - symobj->get_opd_ent(value - opd_addr, dest_shndx, &sec_off); + *dest_shndx = symobj->get_opd_ent(value - opd_addr, &sec_off); Address sec_addr = symobj->get_output_section_offset(*dest_shndx); gold_assert(sec_addr != invalid_address); sec_addr += symobj->output_section(*dest_shndx)->address(); |