* powerpc.cc (Powerpc_relobj::get_opd_ent): Make const.
authorAlan Modra <amodra@gmail.com>
Wed, 5 Sep 2012 02:54:26 +0000 (02:54 +0000)
committerAlan Modra <amodra@gmail.com>
Wed, 5 Sep 2012 02:54:26 +0000 (02:54 +0000)
(Powerpc_relocate_functions::Status): New typedef.
(Target_powerpc::Scan::get_reference_flags): Handle more relocs.
(Target_powerpc::Scan::local): Handle REL64.
(Target_powerpc::Scan::global): Likewise, and dynamic relocs
for REL32 and REL64.
(Target_powerpc::symval_for_branch): New function, extracted from..
(Target_powerpc::Relocate::relocate): ..here.  Correct plt call
checks.  Report overflow errors.

gold/ChangeLog
gold/powerpc.cc

index ea52ea2..faa228e 100644 (file)
@@ -1,5 +1,17 @@
 2012-09-05  Alan Modra  <amodra@gmail.com>
 
+       * powerpc.cc (Powerpc_relobj::get_opd_ent): Make const.
+       (Powerpc_relocate_functions::Status): New typedef.
+       (Target_powerpc::Scan::get_reference_flags): Handle more relocs.
+       (Target_powerpc::Scan::local): Handle REL64.
+       (Target_powerpc::Scan::global): Likewise, and dynamic relocs
+       for REL32 and REL64.
+       (Target_powerpc::symval_for_branch): New function, extracted from..
+       (Target_powerpc::Relocate::relocate): ..here.  Correct plt call
+       checks.  Report overflow errors.
+
+2012-09-05  Alan Modra  <amodra@gmail.com>
+
        * object.h (Sized_relobj_file::emit_relocs): Delete.
        (Sized_relobj_file::emit_relocs_reltype): Delete.
        * reloc.cc (Sized_relobj_file::do_relocate_sections): Call target
index c4b543d..aa209c2 100644 (file)
@@ -100,7 +100,7 @@ public:
 
   // Return section and offset of function entry for .opd + R_OFF.
   void
-  get_opd_ent(Address r_off, unsigned int* shndx, Address* value)
+  get_opd_ent(Address r_off, unsigned int* shndx, Address* value) const
   {
     size_t ndx = this->opd_ent_ndx(r_off);
     gold_assert(ndx < this->opd_ent_shndx_.size());
@@ -411,6 +411,11 @@ class Target_powerpc : public Sized_target<size, big_endian>
     bool issued_non_pic_error_;
   };
 
+  Address
+  symval_for_branch(Address value, const Sized_symbol<size>* gsym,
+                   Powerpc_relobj<size, big_endian>* object,
+                   unsigned int *dest_shndx);
+
   // The class which implements relocation.
   class Relocate
   {
@@ -847,11 +852,11 @@ public:
     check_bitfield
   };
 
-  enum overflow_status
+  typedef enum overflow_status
   {
     status_ok,
     status_overflow
-  };
+  } Status;
 
 private:
   typedef Powerpc_relocate_functions<size, big_endian> This;
@@ -2190,6 +2195,7 @@ Target_powerpc<size, big_endian>::Scan::check_non_pic(Relobj* object,
   // and 64-bit powerpc.
   switch (r_type)
     {
+    case elfcpp::R_POWERPC_NONE:
     case elfcpp::R_POWERPC_RELATIVE:
     case elfcpp::R_POWERPC_GLOB_DAT:
     case elfcpp::R_POWERPC_DTPMOD:
@@ -2197,9 +2203,24 @@ Target_powerpc<size, big_endian>::Scan::check_non_pic(Relobj* object,
     case elfcpp::R_POWERPC_TPREL:
     case elfcpp::R_POWERPC_JMP_SLOT:
     case elfcpp::R_POWERPC_COPY:
+    case elfcpp::R_POWERPC_IRELATIVE:
     case elfcpp::R_POWERPC_ADDR32:
+    case elfcpp::R_POWERPC_UADDR32:
     case elfcpp::R_POWERPC_ADDR24:
+    case elfcpp::R_POWERPC_ADDR16:
+    case elfcpp::R_POWERPC_UADDR16:
+    case elfcpp::R_POWERPC_ADDR16_LO:
+    case elfcpp::R_POWERPC_ADDR16_HI:
+    case elfcpp::R_POWERPC_ADDR16_HA:
+    case elfcpp::R_POWERPC_ADDR14:
+    case elfcpp::R_POWERPC_ADDR14_BRTAKEN:
+    case elfcpp::R_POWERPC_ADDR14_BRNTAKEN:
+    case elfcpp::R_POWERPC_REL32:
     case elfcpp::R_POWERPC_REL24:
+    case elfcpp::R_POWERPC_TPREL16:
+    case elfcpp::R_POWERPC_TPREL16_LO:
+    case elfcpp::R_POWERPC_TPREL16_HI:
+    case elfcpp::R_POWERPC_TPREL16_HA:
       return;
 
     default:
@@ -2212,34 +2233,22 @@ Target_powerpc<size, big_endian>::Scan::check_non_pic(Relobj* object,
        {
          // These are the relocation types supported only on 64-bit.
        case elfcpp::R_PPC64_ADDR64:
-       case elfcpp::R_PPC64_TPREL16_LO_DS:
-       case elfcpp::R_PPC64_TPREL16_DS:
-       case elfcpp::R_POWERPC_TPREL16:
-       case elfcpp::R_POWERPC_TPREL16_LO:
-       case elfcpp::R_POWERPC_TPREL16_HI:
-       case elfcpp::R_POWERPC_TPREL16_HA:
-       case elfcpp::R_PPC64_TPREL16_HIGHER:
-       case elfcpp::R_PPC64_TPREL16_HIGHEST:
-       case elfcpp::R_PPC64_TPREL16_HIGHERA:
-       case elfcpp::R_PPC64_TPREL16_HIGHESTA:
-       case elfcpp::R_PPC64_ADDR16_LO_DS:
-       case elfcpp::R_POWERPC_ADDR16_LO:
-       case elfcpp::R_POWERPC_ADDR16_HI:
-       case elfcpp::R_POWERPC_ADDR16_HA:
-       case elfcpp::R_POWERPC_ADDR30:
        case elfcpp::R_PPC64_UADDR64:
-       case elfcpp::R_POWERPC_UADDR32:
-       case elfcpp::R_POWERPC_ADDR16:
-       case elfcpp::R_POWERPC_UADDR16:
+       case elfcpp::R_PPC64_JMP_IREL:
        case elfcpp::R_PPC64_ADDR16_DS:
+       case elfcpp::R_PPC64_ADDR16_LO_DS:
        case elfcpp::R_PPC64_ADDR16_HIGHER:
        case elfcpp::R_PPC64_ADDR16_HIGHEST:
        case elfcpp::R_PPC64_ADDR16_HIGHERA:
        case elfcpp::R_PPC64_ADDR16_HIGHESTA:
-       case elfcpp::R_POWERPC_ADDR14_BRTAKEN:
-       case elfcpp::R_POWERPC_ADDR14_BRNTAKEN:
-       case elfcpp::R_POWERPC_REL32:
        case elfcpp::R_PPC64_REL64:
+       case elfcpp::R_POWERPC_ADDR30:
+       case elfcpp::R_PPC64_TPREL16_DS:
+       case elfcpp::R_PPC64_TPREL16_LO_DS:
+       case elfcpp::R_PPC64_TPREL16_HIGHER:
+       case elfcpp::R_PPC64_TPREL16_HIGHEST:
+       case elfcpp::R_PPC64_TPREL16_HIGHERA:
+       case elfcpp::R_PPC64_TPREL16_HIGHESTA:
          return;
 
        default:
@@ -2251,6 +2260,12 @@ Target_powerpc<size, big_endian>::Scan::check_non_pic(Relobj* object,
       switch (r_type)
        {
          // These are the relocation types supported only on 32-bit.
+         // ??? glibc ld.so doesn't need to support these.
+       case elfcpp::R_POWERPC_DTPREL16:
+       case elfcpp::R_POWERPC_DTPREL16_LO:
+       case elfcpp::R_POWERPC_DTPREL16_HI:
+       case elfcpp::R_POWERPC_DTPREL16_HA:
+         return;
 
        default:
          break;
@@ -2361,6 +2376,7 @@ Target_powerpc<size, big_endian>::Scan::local(
        }
       break;
 
+    case elfcpp::R_PPC64_REL64:
     case elfcpp::R_POWERPC_REL32:
     case elfcpp::R_POWERPC_REL24:
     case elfcpp::R_PPC_LOCAL24PC:
@@ -2670,35 +2686,36 @@ Target_powerpc<size, big_endian>::Scan::global(
 
     case elfcpp::R_PPC_PLTREL24:
     case elfcpp::R_POWERPC_REL24:
-      {
-       if (gsym->needs_plt_entry()
-           || (!gsym->final_value_is_known()
-                && !(gsym->is_defined()
-                     && !gsym->is_from_dynobj()
-                     && !gsym->is_preemptible())))
-         target->make_plt_entry(layout, gsym, reloc, object);
-       // Make a dynamic relocation if necessary.
-       if (needs_dynamic_reloc<size>(gsym, Scan::get_reference_flags(r_type)))
-         {
-           if (gsym->may_need_copy_reloc())
-             {
-               target->copy_reloc(symtab, layout, object,
-                                  data_shndx, output_section, gsym,
-                                  reloc);
-             }
-           else
-             {
-               Reloc_section* rela_dyn = target->rela_dyn_section(layout);
-               check_non_pic(object, r_type);
-               rela_dyn->add_global(gsym, r_type, output_section, object,
-                                    data_shndx, reloc.get_r_offset(),
-                                    reloc.get_r_addend());
-             }
-         }
-      }
-      break;
+      if (gsym->needs_plt_entry()
+         || (!gsym->final_value_is_known()
+             && (gsym->is_undefined()
+                 || gsym->is_from_dynobj()
+                 || gsym->is_preemptible())))
+       target->make_plt_entry(layout, gsym, reloc, object);
+      // Fall thru
 
+    case elfcpp::R_PPC64_REL64:
     case elfcpp::R_POWERPC_REL32:
+      // Make a dynamic relocation if necessary.
+      if (needs_dynamic_reloc<size>(gsym, Scan::get_reference_flags(r_type)))
+       {
+         if (gsym->may_need_copy_reloc())
+           {
+             target->copy_reloc(symtab, layout, object,
+                                data_shndx, output_section, gsym,
+                                reloc);
+           }
+         else
+           {
+             Reloc_section* rela_dyn = target->rela_dyn_section(layout);
+             check_non_pic(object, r_type);
+             rela_dyn->add_global(gsym, r_type, output_section, object,
+                                  data_shndx, reloc.get_r_offset(),
+                                  reloc.get_r_addend());
+           }
+       }
+      break;
+
     case elfcpp::R_POWERPC_REL16:
     case elfcpp::R_POWERPC_REL16_LO:
     case elfcpp::R_POWERPC_REL16_HI:
@@ -3022,6 +3039,43 @@ Target_powerpc<size, big_endian>::do_finalize_sections(
     this->copy_relocs_.emit(this->rela_dyn_section(layout));
 }
 
+// Return the value to use for a branch relocation.
+
+template<int size, bool big_endian>
+typename elfcpp::Elf_types<size>::Elf_Addr
+Target_powerpc<size, big_endian>::symval_for_branch(
+    Address value,
+    const Sized_symbol<size>* gsym,
+    Powerpc_relobj<size, big_endian>* object,
+    unsigned int *dest_shndx)
+{
+  *dest_shndx = 0;
+  if (size == 32)
+    return value;
+
+  // If the symbol is defined in an opd section, ie. is a function
+  // descriptor, use the function descriptor code entry address
+  Powerpc_relobj<size, big_endian>* symobj = object;
+  if (gsym != NULL)
+    symobj = static_cast<Powerpc_relobj<size, big_endian>*>(gsym->object());
+  unsigned int shndx = symobj->opd_shndx();
+  if (shndx == 0)
+    return value;
+  Address opd_addr = symobj->get_output_section_offset(shndx);
+  gold_assert(opd_addr != invalid_address);
+  opd_addr += symobj->output_section(shndx)->address();
+  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);
+      Address sec_addr = symobj->get_output_section_offset(*dest_shndx);
+      gold_assert(sec_addr != invalid_address);
+      sec_addr += symobj->output_section(*dest_shndx)->address();
+      value = sec_addr + sec_off;
+    }
+  return value;
+}
+
 // Perform a relocation.
 
 template<int size, bool big_endian>
@@ -3060,8 +3114,8 @@ Target_powerpc<size, big_endian>::Relocate::relocate(
 
   typedef Powerpc_relocate_functions<size, big_endian> Reloc;
   typedef typename elfcpp::Swap<32, big_endian>::Valtype Insn;
-  const Powerpc_relobj<size, big_endian>* const object
-    = static_cast<const Powerpc_relobj<size, big_endian>*>(relinfo->object);
+  Powerpc_relobj<size, big_endian>* const object
+    = static_cast<Powerpc_relobj<size, big_endian>*>(relinfo->object);
   Address value = 0;
   bool has_plt_value = false;
   if (gsym != NULL
@@ -3111,17 +3165,50 @@ Target_powerpc<size, big_endian>::Relocate::relocate(
          bool can_plt_call = false;
          if (rela.get_r_offset() + 8 <= view_size)
            {
+             Valtype insn = elfcpp::Swap<32, big_endian>::readval(wv);
              Valtype insn2 = elfcpp::Swap<32, big_endian>::readval(wv + 1);
-             if (insn2 == nop
-                 || insn2 == cror_15_15_15 || insn2 == cror_31_31_31)
+             if ((insn & 1) != 0
+                 && (insn2 == nop
+                     || insn2 == cror_15_15_15 || insn2 == cror_31_31_31))
                {
                  elfcpp::Swap<32, big_endian>::writeval(wv + 1, ld_2_1 + 40);
                  can_plt_call = true;
                }
            }
          if (!can_plt_call)
-           gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
-                                  _("call lacks nop, can't restore toc"));
+           {
+             // If we don't have a branch and link followed by a nop,
+             // we can't go via the plt because there is no place to
+             // put a toc restoring instruction.
+             // Unless we know we won't be returning.
+             if (strcmp(gsym->name(), "__libc_start_main") == 0)
+               can_plt_call = true;
+           }
+         if (!can_plt_call)
+           {
+             // This is not an error in one special case: A self
+             // call.  It isn't possible to cheaply verify we have
+             // such a call so just check for a call to the same
+             // section.
+             bool ok = false;
+             if (gsym->source() == Symbol::FROM_OBJECT
+                 && gsym->object() == object)
+               {
+                 Address addend = rela.get_r_addend();
+                 unsigned int dest_shndx;
+                 value = psymval->value(object, addend);
+                 value = target->symval_for_branch(value, gsym, object,
+                                                   &dest_shndx);
+                 bool is_ordinary;
+                 if (dest_shndx == 0)
+                   dest_shndx = gsym->shndx(&is_ordinary);
+                 ok = dest_shndx == relinfo->data_shndx;
+               }
+             if (!ok)
+               gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
+                                      _("call lacks nop, can't restore toc; "
+                                        "recompile with -fPIC"));
+           }
        }
     }
   else if (r_type == elfcpp::R_POWERPC_GOT_TLSGD16
@@ -3365,34 +3452,13 @@ Target_powerpc<size, big_endian>::Relocate::relocate(
   else
     {
       Address addend = 0;
+      unsigned int dest_shndx;
       if (r_type != elfcpp::R_PPC_PLTREL24)
        addend = rela.get_r_addend();
       if (size == 64 || !has_plt_value)
        value = psymval->value(object, addend);
       if (size == 64 && is_branch_reloc(r_type))
-       {
-         // If the symbol is defined in an opd section, ie. is a function
-         // descriptor, use the function descriptor code entry address
-         Powerpc_relobj<size, big_endian>* symobj = const_cast
-           <Powerpc_relobj<size, big_endian>*>(object);
-         if (gsym != NULL)
-           symobj = static_cast
-             <Powerpc_relobj<size, big_endian>*>(gsym->object());
-         unsigned int shndx = symobj->opd_shndx();
-         Address opd_addr = symobj->get_output_section_offset(shndx);
-         gold_assert(opd_addr != invalid_address);
-         opd_addr += symobj->output_section(shndx)->address();
-         if (value >= opd_addr
-             && value < opd_addr + symobj->section_size(shndx))
-           {
-             Address sec_off;
-             symobj->get_opd_ent(value - opd_addr, &shndx, &sec_off);
-             Address sec_addr = symobj->get_output_section_offset(shndx);
-             gold_assert(sec_addr != invalid_address);
-             sec_addr += symobj->output_section(shndx)->address();
-             value = sec_addr + sec_off;
-           }
-       }
+       value = target->symval_for_branch(value, gsym, object, &dest_shndx);
     }
 
   switch (r_type)
@@ -3562,6 +3628,8 @@ Target_powerpc<size, big_endian>::Relocate::relocate(
       break;
     }
 
+  typename Powerpc_relocate_functions<size, big_endian>::Status status
+    = Powerpc_relocate_functions<size, big_endian>::status_ok;
   switch (r_type)
     {
     case elfcpp::R_POWERPC_NONE:
@@ -3582,7 +3650,7 @@ Target_powerpc<size, big_endian>::Relocate::relocate(
       if (size == 64)
        Reloc::addr64(view, value);
       else
-       Reloc::addr32(view, value, overflow);
+       status = Reloc::addr32(view, value, overflow);
       break;
 
     case elfcpp::R_PPC64_UADDR64:
@@ -3591,25 +3659,25 @@ Target_powerpc<size, big_endian>::Relocate::relocate(
 
     case elfcpp::R_POWERPC_ADDR32:
     case elfcpp::R_POWERPC_REL32:
-      Reloc::addr32(view, value, overflow);
+      status = Reloc::addr32(view, value, overflow);
       break;
 
     case elfcpp::R_POWERPC_UADDR32:
-      Reloc::addr32_u(view, value, overflow);
+      status = Reloc::addr32_u(view, value, overflow);
       break;
 
     case elfcpp::R_POWERPC_ADDR24:
     case elfcpp::R_POWERPC_REL24:
     case elfcpp::R_PPC_PLTREL24:
     case elfcpp::R_PPC_LOCAL24PC:
-      Reloc::addr24(view, value, overflow);
+      status = Reloc::addr24(view, value, overflow);
       break;
 
     case elfcpp::R_POWERPC_GOT_DTPREL16:
     case elfcpp::R_POWERPC_GOT_DTPREL16_LO:
       if (size == 64)
        {
-         Reloc::addr16_ds(view, value, overflow);
+         status = Reloc::addr16_ds(view, value, overflow);
          break;
        }
     case elfcpp::R_POWERPC_ADDR16:
@@ -3632,11 +3700,11 @@ Target_powerpc<size, big_endian>::Relocate::relocate(
     case elfcpp::R_POWERPC_GOT_TLSGD16_LO:
     case elfcpp::R_POWERPC_GOT_TLSLD16_LO:
     case elfcpp::R_POWERPC_GOT_TPREL16_LO:
-      Reloc::addr16(view, value, overflow);
+      status = Reloc::addr16(view, value, overflow);
       break;
 
     case elfcpp::R_POWERPC_UADDR16:
-      Reloc::addr16_u(view, value, overflow);
+      status = Reloc::addr16_u(view, value, overflow);
       break;
 
     case elfcpp::R_POWERPC_ADDR16_HI:
@@ -3721,7 +3789,7 @@ Target_powerpc<size, big_endian>::Relocate::relocate(
     case elfcpp::R_PPC64_GOT16_LO_DS:
     case elfcpp::R_PPC64_SECTOFF_DS:
     case elfcpp::R_PPC64_SECTOFF_LO_DS:
-      Reloc::addr16_ds(view, value, overflow);
+      status = Reloc::addr16_ds(view, value, overflow);
       break;
 
     case elfcpp::R_POWERPC_ADDR14:
@@ -3730,7 +3798,7 @@ Target_powerpc<size, big_endian>::Relocate::relocate(
     case elfcpp::R_POWERPC_REL14:
     case elfcpp::R_POWERPC_REL14_BRTAKEN:
     case elfcpp::R_POWERPC_REL14_BRNTAKEN:
-      Reloc::addr14(view, value, overflow);
+      status = Reloc::addr14(view, value, overflow);
       break;
 
     case elfcpp::R_POWERPC_COPY:
@@ -3791,6 +3859,9 @@ Target_powerpc<size, big_endian>::Relocate::relocate(
                             r_type);
       break;
     }
+  if (status != Powerpc_relocate_functions<size, big_endian>::status_ok)
+    gold_error_at_location(relinfo, relnum, rela.get_r_offset(),
+                          _("relocation overflow"));
 
   return true;
 }