merge from gcc
[deliverable/binutils-gdb.git] / gold / reloc.cc
index 0842a73ca83a78d7725a1fbf0ea9343bae6777dc..7fb5cea7d50556ca167d963c79b791756bd4e438 100644 (file)
@@ -363,7 +363,8 @@ Sized_relobj<size, big_endian>::do_gc_process_relocs(const General_options& opti
                                               Layout* layout,
                                               Read_relocs_data* rd)
 {  
-  Sized_target<size, big_endian>* target = this->sized_target();
+  Sized_target<size, big_endian>* target =
+    parameters->sized_target<size, big_endian>();
 
   const unsigned char* local_symbols;
   if (rd->local_symbols == NULL)
@@ -403,7 +404,8 @@ Sized_relobj<size, big_endian>::do_scan_relocs(const General_options& options,
                                               Layout* layout,
                                               Read_relocs_data* rd)
 {
-  Sized_target<size, big_endian>* target = this->sized_target();
+  Sized_target<size, big_endian>* target =
+    parameters->sized_target<size, big_endian>();
 
   const unsigned char* local_symbols;
   if (rd->local_symbols == NULL)
@@ -802,7 +804,8 @@ Sized_relobj<size, big_endian>::relocate_sections(
     Views* pviews)
 {
   unsigned int shnum = this->shnum();
-  Sized_target<size, big_endian>* target = this->sized_target();
+  Sized_target<size, big_endian>* target =
+    parameters->sized_target<size, big_endian>();
 
   const Output_sections& out_sections(this->output_sections());
   const std::vector<Address>& out_offsets(this->section_offsets_);
@@ -885,39 +888,36 @@ Sized_relobj<size, big_endian>::relocate_sections(
 
       relinfo.reloc_shndx = i;
       relinfo.data_shndx = index;
+      unsigned char* view = (*pviews)[index].view;
+      Address address = (*pviews)[index].address;
+      section_size_type view_size = (*pviews)[index].view_size;
+
+      Reloc_symbol_changes* reloc_map = NULL;
+      if (this->uses_split_stack() && output_offset != invalid_address)
+       {
+         typename This::Shdr data_shdr(pshdrs + index * This::shdr_size);
+         if ((data_shdr.get_sh_flags() & elfcpp::SHF_EXECINSTR) != 0)
+           this->split_stack_adjust(symtab, pshdrs, sh_type, index,
+                                    prelocs, reloc_count, view, view_size,
+                                    &reloc_map);
+       }
+
       if (!parameters->options().relocatable())
        {
-         target->relocate_section(&relinfo,
-                                  sh_type,
-                                  prelocs,
-                                  reloc_count,
-                                  os,
+         target->relocate_section(&relinfo, sh_type, prelocs, reloc_count, os,
                                   output_offset == invalid_address,
-                                  (*pviews)[index].view,
-                                  (*pviews)[index].address,
-                                  (*pviews)[index].view_size);
+                                  view, address, view_size, reloc_map);
          if (parameters->options().emit_relocs())
            this->emit_relocs(&relinfo, i, sh_type, prelocs, reloc_count,
-                             os, output_offset,
-                             (*pviews)[index].view,
-                             (*pviews)[index].address,
-                             (*pviews)[index].view_size,
-                             (*pviews)[i].view,
-                             (*pviews)[i].view_size);
+                             os, output_offset, view, address, view_size,
+                             (*pviews)[i].view, (*pviews)[i].view_size);
        }
       else
        {
          Relocatable_relocs* rr = this->relocatable_relocs(i);
-         target->relocate_for_relocatable(&relinfo,
-                                          sh_type,
-                                          prelocs,
-                                          reloc_count,
-                                          os,
-                                          output_offset,
-                                          rr,
-                                          (*pviews)[index].view,
-                                          (*pviews)[index].address,
-                                          (*pviews)[index].view_size,
+         target->relocate_for_relocatable(&relinfo, sh_type, prelocs,
+                                          reloc_count, os, output_offset, rr,
+                                          view, address, view_size,
                                           (*pviews)[i].view,
                                           (*pviews)[i].view_size);
        }
@@ -1022,6 +1022,244 @@ Sized_relobj<size, big_endian>::free_input_to_output_maps()
     }
 }
 
+// If an object was compiled with -fsplit-stack, this is called to
+// check whether any relocations refer to functions defined in objects
+// which were not compiled with -fsplit-stack.  If they were, then we
+// need to apply some target-specific adjustments to request
+// additional stack space.
+
+template<int size, bool big_endian>
+void
+Sized_relobj<size, big_endian>::split_stack_adjust(
+    const Symbol_table* symtab,
+    const unsigned char* pshdrs,
+    unsigned int sh_type,
+    unsigned int shndx,
+    const unsigned char* prelocs,
+    size_t reloc_count,
+    unsigned char* view,
+    section_size_type view_size,
+    Reloc_symbol_changes** reloc_map)
+{
+  if (sh_type == elfcpp::SHT_REL)
+    this->split_stack_adjust_reltype<elfcpp::SHT_REL>(symtab, pshdrs, shndx,
+                                                     prelocs, reloc_count,
+                                                     view, view_size,
+                                                     reloc_map);
+  else
+    {
+      gold_assert(sh_type == elfcpp::SHT_RELA);
+      this->split_stack_adjust_reltype<elfcpp::SHT_RELA>(symtab, pshdrs, shndx,
+                                                        prelocs, reloc_count,
+                                                        view, view_size,
+                                                        reloc_map);
+    }
+}
+
+// Adjust for -fsplit-stack, templatized on the type of the relocation
+// section.
+
+template<int size, bool big_endian>
+template<int sh_type>
+void
+Sized_relobj<size, big_endian>::split_stack_adjust_reltype(
+    const Symbol_table* symtab,
+    const unsigned char* pshdrs,
+    unsigned int shndx,
+    const unsigned char* prelocs,
+    size_t reloc_count,
+    unsigned char* view,
+    section_size_type view_size,
+    Reloc_symbol_changes** reloc_map)
+{
+  typedef typename Reloc_types<sh_type, size, big_endian>::Reloc Reltype;
+  const int reloc_size = Reloc_types<sh_type, size, big_endian>::reloc_size;
+
+  size_t local_count = this->local_symbol_count();
+
+  std::vector<section_offset_type> non_split_refs;
+
+  const unsigned char* pr = prelocs;
+  for (size_t i = 0; i < reloc_count; ++i, pr += reloc_size)
+    {
+      Reltype reloc(pr);
+
+      typename elfcpp::Elf_types<size>::Elf_WXword r_info = reloc.get_r_info();
+      unsigned int r_sym = elfcpp::elf_r_sym<size>(r_info);
+      if (r_sym < local_count)
+       continue;
+
+      const Symbol* gsym = this->global_symbol(r_sym);
+      gold_assert(gsym != NULL);
+      if (gsym->is_forwarder())
+       gsym = symtab->resolve_forwards(gsym);
+
+      // See if this relocation refers to a function defined in an
+      // object compiled without -fsplit-stack.  Note that we don't
+      // care about the type of relocation--this means that in some
+      // cases we will ask for a large stack unnecessarily, but this
+      // is not fatal.  FIXME: Some targets have symbols which are
+      // functions but are not type STT_FUNC, e.g., STT_ARM_TFUNC.
+      if (gsym->type() == elfcpp::STT_FUNC
+         && !gsym->is_undefined()
+         && gsym->source() == Symbol::FROM_OBJECT
+         && !gsym->object()->uses_split_stack())
+       {
+         section_offset_type offset =
+           convert_to_section_size_type(reloc.get_r_offset());
+         non_split_refs.push_back(offset);
+       }
+    }
+
+  if (non_split_refs.empty())
+    return;
+
+  // At this point, every entry in NON_SPLIT_REFS indicates a
+  // relocation which refers to a function in an object compiled
+  // without -fsplit-stack.  We now have to convert that list into a
+  // set of offsets to functions.  First, we find all the functions.
+
+  Function_offsets function_offsets;
+  this->find_functions(pshdrs, shndx, &function_offsets);
+  if (function_offsets.empty())
+    return;
+
+  // Now get a list of the function with references to non split-stack
+  // code.
+
+  Function_offsets calls_non_split;
+  for (std::vector<section_offset_type>::const_iterator p
+        = non_split_refs.begin();
+       p != non_split_refs.end();
+       ++p)
+    {
+      Function_offsets::const_iterator low = function_offsets.lower_bound(*p);
+      if (low == function_offsets.end())
+       --low;
+      else if (low->first == *p)
+       ;
+      else if (low == function_offsets.begin())
+       continue;
+      else
+       --low;
+
+      calls_non_split.insert(*low);
+    }
+  if (calls_non_split.empty())
+    return;
+
+  // Now we have a set of functions to adjust.  The adjustments are
+  // target specific.  Besides changing the output section view
+  // however, it likes, the target may request a relocation change
+  // from one global symbol name to another.
+
+  for (Function_offsets::const_iterator p = calls_non_split.begin();
+       p != calls_non_split.end();
+       ++p)
+    {
+      std::string from;
+      std::string to;
+      parameters->target().calls_non_split(this, shndx, p->first, p->second,
+                                          view, view_size, &from, &to);
+      if (!from.empty())
+       {
+         gold_assert(!to.empty());
+         Symbol* tosym = NULL;
+
+         // Find relocations in the relevant function which are for
+         // FROM.
+         pr = prelocs;
+         for (size_t i = 0; i < reloc_count; ++i, pr += reloc_size)
+           {
+             Reltype reloc(pr);
+
+             typename elfcpp::Elf_types<size>::Elf_WXword r_info =
+               reloc.get_r_info();
+             unsigned int r_sym = elfcpp::elf_r_sym<size>(r_info);
+             if (r_sym < local_count)
+               continue;
+
+             section_offset_type offset =
+               convert_to_section_size_type(reloc.get_r_offset());
+             if (offset < p->first
+                 || (offset
+                     >= (p->first
+                         + static_cast<section_offset_type>(p->second))))
+               continue;
+
+             const Symbol* gsym = this->global_symbol(r_sym);
+             if (from == gsym->name())
+               {
+                 if (tosym == NULL)
+                   {
+                     tosym = symtab->lookup(to.c_str());
+                     if (tosym == NULL)
+                       {
+                         this->error(_("could not convert call "
+                                       "to '%s' to '%s'"),
+                                     from.c_str(), to.c_str());
+                         break;
+                       }
+                   }
+
+                 if (*reloc_map == NULL)
+                   *reloc_map = new Reloc_symbol_changes(reloc_count);
+                 (*reloc_map)->set(i, tosym);
+               }
+           }
+       }
+    }
+}
+
+// Find all the function in this object defined in section SHNDX.
+// Store their offsets in the section in FUNCTION_OFFSETS.
+
+template<int size, bool big_endian>
+void
+Sized_relobj<size, big_endian>::find_functions(
+    const unsigned char* pshdrs,
+    unsigned int shndx,
+    Sized_relobj<size, big_endian>::Function_offsets* function_offsets)
+{
+  // We need to read the symbols to find the functions.  If we wanted
+  // to, we could cache reading the symbols across all sections in the
+  // object.
+  const unsigned int symtab_shndx = this->symtab_shndx_;
+  typename This::Shdr symtabshdr(pshdrs + symtab_shndx * This::shdr_size);
+  gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
+
+  typename elfcpp::Elf_types<size>::Elf_WXword sh_size =
+    symtabshdr.get_sh_size();
+  const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(),
+                                             sh_size, true, true);
+
+  const int sym_size = This::sym_size;
+  const unsigned int symcount = sh_size / sym_size;
+  for (unsigned int i = 0; i < symcount; ++i, psyms += sym_size)
+    {
+      typename elfcpp::Sym<size, big_endian> isym(psyms);
+
+      // FIXME: Some targets can have functions which do not have type
+      // STT_FUNC, e.g., STT_ARM_TFUNC.
+      if (isym.get_st_type() != elfcpp::STT_FUNC
+         || isym.get_st_size() == 0)
+       continue;
+
+      bool is_ordinary;
+      unsigned int sym_shndx = this->adjust_sym_shndx(i, isym.get_st_shndx(),
+                                                     &is_ordinary);
+      if (!is_ordinary || sym_shndx != shndx)
+       continue;
+
+      section_offset_type value =
+       convert_to_section_size_type(isym.get_st_value());
+      section_size_type fnsize =
+       convert_to_section_size_type(isym.get_st_size());
+
+      (*function_offsets)[value] = fnsize;
+    }
+}
+
 // Class Merged_symbol_value.
 
 template<int size>
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