Support R_SPARC_WDISP10 and R_SPARC_H34.
[external/binutils.git] / gold / target-reloc.h
index 3205e36..6efcdf4 100644 (file)
@@ -1,6 +1,6 @@
 // target-reloc.h -- target specific relocation support  -*- C++ -*-
 
-// Copyright 2006, 2007, 2008 Free Software Foundation, Inc.
+// Copyright 2006, 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
 // Written by Ian Lance Taylor <iant@google.com>.
 
 // This file is part of gold.
@@ -25,6 +25,7 @@
 
 #include "elfcpp.h"
 #include "symtab.h"
+#include "object.h"
 #include "reloc.h"
 #include "reloc-types.h"
 
@@ -35,18 +36,17 @@ namespace gold
 // template parameter Scan must be a class type which provides two
 // functions: local() and global().  Those functions implement the
 // machine specific part of scanning.  We do it this way to
-// avoidmaking a function call for each relocation, and to avoid
+// avoid making a function call for each relocation, and to avoid
 // repeating the generic code for each target.
 
 template<int size, bool big_endian, typename Target_type, int sh_type,
         typename Scan>
 inline void
 scan_relocs(
-    const General_options& options,
     Symbol_table* symtab,
     Layout* layout,
     Target_type* target,
-    Sized_relobj<size, big_endian>* object,
+    Sized_relobj_file<size, big_endian>* object,
     unsigned int data_shndx,
     const unsigned char* prelocs,
     size_t reloc_count,
@@ -83,7 +83,8 @@ scan_relocs(
          shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
          if (is_ordinary
              && shndx != elfcpp::SHN_UNDEF
-             && !object->is_section_included(shndx))
+             && !object->is_section_included(shndx)
+              && !symtab->is_section_folded(object, shndx))
            {
              // RELOC is a relocation against a local symbol in a
              // section we are discarding.  We can ignore this
@@ -102,8 +103,7 @@ scan_relocs(
 
              continue;
            }
-
-         scan.local(options, symtab, layout, target, object, data_shndx,
+         scan.local(symtab, layout, target, object, data_shndx,
                     output_section, reloc, r_type, lsym);
        }
       else
@@ -113,7 +113,7 @@ scan_relocs(
          if (gsym->is_forwarder())
            gsym = symtab->resolve_forwards(gsym);
 
-         scan.global(options, symtab, layout, target, object, data_shndx,
+         scan.global(symtab, layout, target, object, data_shndx,
                      output_section, reloc, r_type, gsym);
        }
     }
@@ -144,6 +144,82 @@ get_comdat_behavior(const char* name)
   return CB_WARNING;
 }
 
+// Give an error for a symbol with non-default visibility which is not
+// defined locally.
+
+inline void
+visibility_error(const Symbol* sym)
+{
+  const char* v;
+  switch (sym->visibility())
+    {
+    case elfcpp::STV_INTERNAL:
+      v = _("internal");
+      break;
+    case elfcpp::STV_HIDDEN:
+      v = _("hidden");
+      break;
+    case elfcpp::STV_PROTECTED:
+      v = _("protected");
+      break;
+    default:
+      gold_unreachable();
+    }
+  gold_error(_("%s symbol '%s' is not defined locally"),
+            v, sym->name());
+}
+
+// Return true if we are should issue an error saying that SYM is an
+// undefined symbol.  This is called if there is a relocation against
+// SYM.
+
+inline bool
+issue_undefined_symbol_error(const Symbol* sym)
+{
+  // We only report global symbols.
+  if (sym == NULL)
+    return false;
+
+  // We only report undefined symbols.
+  if (!sym->is_undefined() && !sym->is_placeholder())
+    return false;
+
+  // We don't report weak symbols.
+  if (sym->binding() == elfcpp::STB_WEAK)
+    return false;
+
+  // We don't report symbols defined in discarded sections.
+  if (sym->is_defined_in_discarded_section())
+    return false;
+
+  // If the target defines this symbol, don't report it here.
+  if (parameters->target().is_defined_by_abi(sym))
+    return false;
+
+  // See if we've been told to ignore whether this symbol is
+  // undefined.
+  const char* const u = parameters->options().unresolved_symbols();
+  if (u != NULL)
+    {
+      if (strcmp(u, "ignore-all") == 0)
+       return false;
+      if (strcmp(u, "report-all") == 0)
+       return true;
+      if (strcmp(u, "ignore-in-object-files") == 0 && !sym->in_dyn())
+       return false;
+      if (strcmp(u, "ignore-in-shared-libs") == 0 && !sym->in_reg())
+       return false;
+    }
+
+  // When creating a shared library, only report unresolved symbols if
+  // -z defs was used.
+  if (parameters->options().shared() && !parameters->options().defs())
+    return false;
+
+  // Otherwise issue a warning.
+  return true;
+}
+
 // This function implements the generic part of relocation processing.
 // The template parameter Relocate must be a class type which provides
 // a single function, relocate(), which implements the machine
@@ -163,6 +239,12 @@ get_comdat_behavior(const char* name)
 // NEEDS_SPECIAL_OFFSET_HANDLING is true, in which case they refer to
 // the output section.
 
+// RELOC_SYMBOL_CHANGES is used for -fsplit-stack support.  If it is
+// not NULL, it is a vector indexed by relocation index.  If that
+// entry is not NULL, it points to a global symbol which used as the
+// symbol for the relocation, ignoring the symbol index in the
+// relocation.
+
 template<int size, bool big_endian, typename Target_type, int sh_type,
         typename Relocate>
 inline void
@@ -175,13 +257,14 @@ relocate_section(
     bool needs_special_offset_handling,
     unsigned char* view,
     typename elfcpp::Elf_types<size>::Elf_Addr view_address,
-    section_size_type view_size)
+    section_size_type view_size,
+    const Reloc_symbol_changes* reloc_symbol_changes)
 {
   typedef typename Reloc_types<sh_type, size, big_endian>::Reloc Reltype;
   const int reloc_size = Reloc_types<sh_type, size, big_endian>::reloc_size;
   Relocate relocate;
 
-  Sized_relobj<size, big_endian>* object = relinfo->object;
+  Sized_relobj_file<size, big_endian>* object = relinfo->object;
   unsigned int local_count = object->local_symbol_count();
 
   Comdat_behavior comdat_behavior = CB_UNDETERMINED;
@@ -210,7 +293,11 @@ relocate_section(
 
       Symbol_value<size> symval;
       const Symbol_value<size> *psymval;
-      if (r_sym < local_count)
+      bool is_defined_in_discarded_section;
+      unsigned int shndx;
+      if (r_sym < local_count
+         && (reloc_symbol_changes == NULL
+             || (*reloc_symbol_changes)[i] == NULL))
        {
          sym = NULL;
          psymval = object->local_symbol(r_sym);
@@ -218,58 +305,86 @@ relocate_section(
           // If the local symbol belongs to a section we are discarding,
           // and that section is a debug section, try to find the
           // corresponding kept section and map this symbol to its
-          // counterpart in the kept section.
+          // counterpart in the kept section.  The symbol must not 
+          // correspond to a section we are folding.
          bool is_ordinary;
-         unsigned int shndx = psymval->input_shndx(&is_ordinary);
-         if (is_ordinary
-             && shndx != elfcpp::SHN_UNDEF
-             && !object->is_section_included(shndx))
-           {
-             if (comdat_behavior == CB_UNDETERMINED)
-               {
-                 std::string name = object->section_name(relinfo->data_shndx);
-                 comdat_behavior = get_comdat_behavior(name.c_str());
-               }
-             if (comdat_behavior == CB_PRETEND)
-               {
-                  bool found;
-                 typename elfcpp::Elf_types<size>::Elf_Addr value =
-                   object->map_to_kept_section(shndx, &found);
-                 if (found)
-                   symval.set_output_value(value + psymval->input_value());
-                  else
-                    symval.set_output_value(0);
-               }
-             else
-               {
-                 if (comdat_behavior == CB_WARNING)
-                    gold_warning_at_location(relinfo, i, offset,
-                                             _("Relocation refers to discarded "
-                                               "comdat section"));
-                  symval.set_output_value(0);
-               }
-             symval.set_no_output_symtab_entry();
-             psymval = &symval;
-           }
+         shndx = psymval->input_shndx(&is_ordinary);
+         is_defined_in_discarded_section =
+           (is_ordinary
+            && shndx != elfcpp::SHN_UNDEF
+            && !object->is_section_included(shndx)
+            && !relinfo->symtab->is_section_folded(object, shndx));
        }
       else
        {
-         const Symbol* gsym = object->global_symbol(r_sym);
-         gold_assert(gsym != NULL);
-         if (gsym->is_forwarder())
-           gsym = relinfo->symtab->resolve_forwards(gsym);
+         const Symbol* gsym;
+         if (reloc_symbol_changes != NULL
+             && (*reloc_symbol_changes)[i] != NULL)
+           gsym = (*reloc_symbol_changes)[i];
+         else
+           {
+             gsym = object->global_symbol(r_sym);
+             gold_assert(gsym != NULL);
+             if (gsym->is_forwarder())
+               gsym = relinfo->symtab->resolve_forwards(gsym);
+           }
 
          sym = static_cast<const Sized_symbol<size>*>(gsym);
-         if (sym->has_symtab_index())
+         if (sym->has_symtab_index() && sym->symtab_index() != -1U)
            symval.set_output_symtab_index(sym->symtab_index());
          else
            symval.set_no_output_symtab_entry();
          symval.set_output_value(sym->value());
+         if (gsym->type() == elfcpp::STT_TLS)
+           symval.set_is_tls_symbol();
+         else if (gsym->type() == elfcpp::STT_GNU_IFUNC)
+           symval.set_is_ifunc_symbol();
          psymval = &symval;
+
+         is_defined_in_discarded_section =
+           (gsym->is_defined_in_discarded_section()
+            && gsym->is_undefined());
+         shndx = 0;
+       }
+
+      Symbol_value<size> symval2;
+      if (is_defined_in_discarded_section)
+       {
+         if (comdat_behavior == CB_UNDETERMINED)
+           {
+             std::string name = object->section_name(relinfo->data_shndx);
+             comdat_behavior = get_comdat_behavior(name.c_str());
+           }
+         if (comdat_behavior == CB_PRETEND)
+           {
+             // FIXME: This case does not work for global symbols.
+             // We have no place to store the original section index.
+             // Fortunately this does not matter for comdat sections,
+             // only for sections explicitly discarded by a linker
+             // script.
+             bool found;
+             typename elfcpp::Elf_types<size>::Elf_Addr value =
+               object->map_to_kept_section(shndx, &found);
+             if (found)
+               symval2.set_output_value(value + psymval->input_value());
+             else
+               symval2.set_output_value(0);
+           }
+         else
+           {
+             if (comdat_behavior == CB_WARNING)
+               gold_warning_at_location(relinfo, i, offset,
+                                        _("relocation refers to discarded "
+                                          "section"));
+             symval2.set_output_value(0);
+           }
+         symval2.set_no_output_symtab_entry();
+         psymval = &symval2;
        }
 
-      if (!relocate.relocate(relinfo, target, i, reloc, r_type, sym, psymval,
-                            view + offset, view_address + offset, view_size))
+      if (!relocate.relocate(relinfo, target, output_section, i, reloc,
+                            r_type, sym, psymval, view + offset,
+                            view_address + offset, view_size))
        continue;
 
       if (offset < 0 || static_cast<section_size_type>(offset) >= view_size)
@@ -280,19 +395,58 @@ relocate_section(
          continue;
        }
 
-      if (sym != NULL
-         && sym->is_undefined()
-         && sym->binding() != elfcpp::STB_WEAK
-          && !target->is_defined_by_abi(sym)
-         && (!parameters->options().shared()       // -shared
-              || parameters->options().defs()))     // -z defs
-       gold_undefined_symbol(sym, relinfo, i, offset);
+      if (issue_undefined_symbol_error(sym))
+       gold_undefined_symbol_at_location(sym, relinfo, i, offset);
+      else if (sym != NULL
+              && sym->visibility() != elfcpp::STV_DEFAULT
+              && (sym->is_undefined() || sym->is_from_dynobj()))
+       visibility_error(sym);
 
       if (sym != NULL && sym->has_warning())
        relinfo->symtab->issue_warning(sym, relinfo, i, offset);
     }
 }
 
+// Apply an incremental relocation.
+
+template<int size, bool big_endian, typename Target_type,
+        typename Relocate>
+void
+apply_relocation(const Relocate_info<size, big_endian>* relinfo,
+                Target_type* target,
+                typename elfcpp::Elf_types<size>::Elf_Addr r_offset,
+                unsigned int r_type,
+                typename elfcpp::Elf_types<size>::Elf_Swxword r_addend,
+                const Symbol* gsym,
+                unsigned char* view,
+                typename elfcpp::Elf_types<size>::Elf_Addr address,
+                section_size_type view_size)
+{
+  // Construct the ELF relocation in a temporary buffer.
+  const int reloc_size = elfcpp::Elf_sizes<size>::rela_size;
+  unsigned char relbuf[reloc_size];
+  elfcpp::Rela<size, big_endian> rel(relbuf);
+  elfcpp::Rela_write<size, big_endian> orel(relbuf);
+  orel.put_r_offset(r_offset);
+  orel.put_r_info(elfcpp::elf_r_info<size>(0, r_type));
+  orel.put_r_addend(r_addend);
+
+  // Setup a Symbol_value for the global symbol.
+  const Sized_symbol<size>* sym = static_cast<const Sized_symbol<size>*>(gsym);
+  Symbol_value<size> symval;
+  gold_assert(sym->has_symtab_index() && sym->symtab_index() != -1U);
+  symval.set_output_symtab_index(sym->symtab_index());
+  symval.set_output_value(sym->value());
+  if (gsym->type() == elfcpp::STT_TLS)
+    symval.set_is_tls_symbol();
+  else if (gsym->type() == elfcpp::STT_GNU_IFUNC)
+    symval.set_is_ifunc_symbol();
+
+  Relocate relocate;
+  relocate.relocate(relinfo, target, NULL, -1U, rel, r_type, sym, &symval,
+                   view + r_offset, address + r_offset, view_size);
+}
+
 // This class may be used as a typical class for the
 // Scan_relocatable_reloc parameter to scan_relocatable_relocs.  The
 // template parameter Classify_reloc must be a class type which
@@ -308,11 +462,11 @@ class Default_scan_relocatable_relocs
   // Return the strategy to use for a local symbol which is not a
   // section symbol, given the relocation type.
   inline Relocatable_relocs::Reloc_strategy
-  local_non_section_strategy(unsigned int r_type, Relobj*)
+  local_non_section_strategy(unsigned int r_type, Relobj*, unsigned int r_sym)
   {
     // We assume that relocation type 0 is NONE.  Targets which are
     // different must override.
-    if (r_type == 0)
+    if (r_type == 0 && r_sym == 0)
       return Relocatable_relocs::RELOC_DISCARD;
     return Relocatable_relocs::RELOC_COPY;
   }
@@ -322,10 +476,6 @@ class Default_scan_relocatable_relocs
   inline Relocatable_relocs::Reloc_strategy
   local_section_strategy(unsigned int r_type, Relobj* object)
   {
-    // We assume that relocation type 0 is NONE.  Targets which are
-    // different must override.
-    if (r_type == 0)
-      return Relocatable_relocs::RELOC_DISCARD;
     if (sh_type == elfcpp::SHT_RELA)
       return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_RELA;
     else
@@ -352,14 +502,8 @@ class Default_scan_relocatable_relocs
   // Return the strategy to use for a global symbol, given the
   // relocation type, the object, and the symbol index.
   inline Relocatable_relocs::Reloc_strategy
-  global_strategy(unsigned int r_type, Relobj*, unsigned int)
-  {
-    // We assume that relocation type 0 is NONE.  Targets which are
-    // different must override.
-    if (r_type == 0)
-      return Relocatable_relocs::RELOC_DISCARD;
-    return Relocatable_relocs::RELOC_COPY;
-  }
+  global_strategy(unsigned int, Relobj*, unsigned int)
+  { return Relocatable_relocs::RELOC_COPY; }
 };
 
 // Scan relocs during a relocatable link.  This is a default
@@ -374,10 +518,9 @@ template<int size, bool big_endian, int sh_type,
         typename Scan_relocatable_reloc>
 void
 scan_relocatable_relocs(
-    const General_options&,
     Symbol_table*,
     Layout*,
-    Sized_relobj<size, big_endian>* object,
+    Sized_relobj_file<size, big_endian>* object,
     unsigned int data_shndx,
     const unsigned char* prelocs,
     size_t reloc_count,
@@ -429,13 +572,17 @@ scan_relocatable_relocs(
                  strategy = Relocatable_relocs::RELOC_DISCARD;
                }
              else if (lsym.get_st_type() != elfcpp::STT_SECTION)
-               strategy = scan.local_non_section_strategy(r_type, object);
+               strategy = scan.local_non_section_strategy(r_type, object,
+                                                          r_sym);
              else
                {
                  strategy = scan.local_section_strategy(r_type, object);
                  if (strategy != Relocatable_relocs::RELOC_DISCARD)
                     object->output_section(shndx)->set_needs_symtab_index();
                }
+
+             if (strategy == Relocatable_relocs::RELOC_COPY)
+               object->set_must_have_output_symtab_entry(r_sym);
            }
        }
 
@@ -457,7 +604,7 @@ relocate_for_relocatable(
     const Relocatable_relocs* rr,
     unsigned char* view,
     typename elfcpp::Elf_types<size>::Elf_Addr view_address,
-    section_size_type,
+    section_size_type view_size,
     unsigned char* reloc_view,
     section_size_type reloc_view_size)
 {
@@ -468,7 +615,7 @@ relocate_for_relocatable(
   const int reloc_size = Reloc_types<sh_type, size, big_endian>::reloc_size;
   const Address invalid_address = static_cast<Address>(0) - 1;
 
-  Sized_relobj<size, big_endian>* const object = relinfo->object;
+  Sized_relobj_file<size, big_endian>* const object = relinfo->object;
   const unsigned int local_count = object->local_symbol_count();
 
   unsigned char* pwrite = reloc_view;
@@ -479,6 +626,19 @@ relocate_for_relocatable(
       if (strategy == Relocatable_relocs::RELOC_DISCARD)
        continue;
 
+      if (strategy == Relocatable_relocs::RELOC_SPECIAL)
+       {
+         // Target wants to handle this relocation.
+         Sized_target<size, big_endian>* target =
+           parameters->sized_target<size, big_endian>();
+         target->relocate_special_relocatable(relinfo, sh_type, prelocs,
+                                              i, output_section,
+                                              offset_in_output_section,
+                                              view, view_address,
+                                              view_size, pwrite);
+         pwrite += reloc_size;
+         continue;
+       }
       Reltype reloc(prelocs);
       Reltype_write reloc_write(pwrite);
 
@@ -494,8 +654,13 @@ relocate_for_relocatable(
          switch (strategy)
            {
            case Relocatable_relocs::RELOC_COPY:
-             new_symndx = object->symtab_index(r_sym);
-             gold_assert(new_symndx != -1U);
+             if (r_sym == 0)
+               new_symndx = 0;
+             else
+               {
+                 new_symndx = object->symtab_index(r_sym);
+                 gold_assert(new_symndx != -1U);
+               }
              break;
 
            case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_RELA:
@@ -504,6 +669,7 @@ relocate_for_relocatable(
            case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_2:
            case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_4:
            case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_8:
+           case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_4_UNALIGNED:
              {
                // We are adjusting a section symbol.  We need to find
                // the symbol table index of the section symbol for
@@ -625,6 +791,12 @@ relocate_for_relocatable(
                                                          psymval);
              break;
 
+           case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_4_UNALIGNED:
+             Relocate_functions<size, big_endian>::rel32_unaligned(padd,
+                                                                   object,
+                                                                   psymval);
+             break;
+
            default:
              gold_unreachable();
            }