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Re: [GOLD] advice on powerpc64 .opd handling


On Wed, Aug 15, 2012 at 03:39:20PM -0700, Ian Lance Taylor wrote:
> I don't really know the answer here.  It sounds like what you need are
> not the contents of the .opd section itself, but the contents of the
> .rela.opd section.  gold will read all the relocs before it does
> anything with them.  Perhaps you can define a do_read_relocs function
> in your Powerpc_relobj class that calls the Sized_relobj_file
> do_read_relocs routine, then looks through the Section_relocs to find
> the .opd relocs, then builds whatever data structure you need out of
> that.

Yes, that's what I've done after a few false starts.  (My first
attempt built up opd entry info in Scan::local and Scan::global.  That
was a bad idea since I'll need opd entry info available for garbage
collection when I get around to tackling that problem.)

Anyway, I'm reasonably happy with the following as now gold generates
a dynamically linked ppc64 "Hello world" that actually runs..  I would
appreciate you reviewing though.

	* powerpc.cc: Formatting and white space.
	(Powerpc_relobj): Rename got2_section_ to special_.
	Add opd_ent_count_, opd_ent_shndx_, opd_ent_off_.
	(Powerpc_relobj::opd_shndx, init_opd, get_opd_ent, set_opd_ent,
	do_read_relocs, opd_ent_ndx): New functions.
	(Target_powerpc::is_branch_reloc): New function.
	(Powerpc_relobj::do_find_special_sections): Find .opd for 64-bit.
	(ld_2_1, cror_15_15_15, cror_31_31_31): New insn constants.
	(Output_data_glink): Rename pltresolve_size to pltresolve_size_.
	(Output_data_glink::pltresolve_size): New function.
	(Output_data_glink::do_write): Correct toc base.  Don't try to use
	uint16_t for 24-bit offset.
	(Target_powerpc::Scan::local): Handle more relocs.
	(Target_powerpc::do_finalize_sections): Set up DT_PPC64_GLINK.
	(Target_powerpc::Relocate::relocate): Correct toc base calculation.
	Plug in toc restoring insn after plt calls.  Translate branches
	to function descriptor symbols to corresponding entry point.
	* symtab.h: Comment typo.

Index: gold/powerpc.cc
===================================================================
RCS file: /cvs/src/src/gold/powerpc.cc,v
retrieving revision 1.49
diff -u -p -r1.49 powerpc.cc
--- gold/powerpc.cc	14 Aug 2012 03:39:03 -0000	1.49
+++ gold/powerpc.cc	16 Aug 2012 12:11:52 -0000
@@ -60,26 +60,93 @@ public:
   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),
-      got2_section_(0)
+      special_(0)
   { }
 
   ~Powerpc_relobj()
   { }
 
+  // The .got2 section shndx.
   unsigned int
   got2_shndx() const
   {
     if (size == 32)
-      return this->got2_section_;
+      return this->special_;
     else
       return 0;
   }
 
+  // The .opd section shndx.
+  unsigned int
+  opd_shndx() const
+  {
+    if (size == 32)
+      return 0;
+    else
+      return this->special_;
+  }
+
+  // Init OPD entry arrays.
+  void
+  init_opd(size_t opd_size)
+  {
+    size_t count = this->opd_ent_ndx(opd_size);
+    this->opd_ent_count_ = count;
+    this->opd_ent_shndx_ = new unsigned int[count];
+    this->opd_ent_off_ = new typename elfcpp::Elf_types<size>::Elf_Off[count];
+    memset(this->opd_ent_shndx_, 0, sizeof(this->opd_ent_shndx_[0]) * count);
+  }
+
+  // Return section and offset of function entry for .opd + R_OFF.
+  void
+  get_opd_ent(typename elfcpp::Elf_types<size>::Elf_Addr r_off,
+	      unsigned int* shndx,
+	      typename elfcpp::Elf_types<size>::Elf_Addr* value)
+  {
+    size_t ndx = this->opd_ent_ndx(r_off);
+    gold_assert(ndx < this->opd_ent_count_);
+    *shndx = this->opd_ent_shndx_[ndx];
+    *value = this->opd_ent_off_[ndx];
+  }
+
+  // Set section and offset of function entry for .opd + R_OFF.
+  void
+  set_opd_ent(typename elfcpp::Elf_types<size>::Elf_Addr r_off,
+	      unsigned int shndx,
+	      typename elfcpp::Elf_types<size>::Elf_Addr value)
+  {
+    size_t ndx = this->opd_ent_ndx(r_off);
+    gold_assert(ndx < this->opd_ent_count_);
+    this->opd_ent_shndx_[ndx] = shndx;
+    this->opd_ent_off_[ndx] = value;
+  }
+
+  // Examine .rela.opd to build info about function entry points.
+  void
+  scan_opd_relocs(size_t reloc_count,
+		  const unsigned char* prelocs,
+		  const unsigned char* plocal_syms);
+
+  void
+  do_read_relocs(Read_relocs_data*);
+
   bool
   do_find_special_sections(Read_symbols_data* sd);
 
 private:
-  unsigned int got2_section_;
+  // Return index into opd_ent_shndx or opd_ent_off array for .opd entry
+  // at OFF.  .opd entries are 24 bytes long, but they can be spaced
+  // 16 bytes apart when the language doesn't use the environment pointer
+  // word.  Thus dividing the entry section offset by 16 will give a
+  // unique index.
+  size_t
+  opd_ent_ndx(size_t off) const
+  { return off >> 4;}
+
+  unsigned int special_;
+  size_t opd_ent_count_;
+  unsigned int* opd_ent_shndx_;
+  typename elfcpp::Elf_types<size>::Elf_Off* opd_ent_off_;
 };
 
 template<int size, bool big_endian>
@@ -342,6 +409,19 @@ class Target_powerpc : public Sized_targ
 	     typename elfcpp::Elf_types<size>::Elf_Addr,
 	     section_size_type);
 
+    inline bool
+    is_branch_reloc(unsigned int r_type) const
+    {
+      return (r_type == elfcpp::R_POWERPC_REL24
+	      || r_type == elfcpp::R_POWERPC_REL14
+	      || r_type == elfcpp::R_POWERPC_REL14_BRTAKEN
+	      || r_type == elfcpp::R_POWERPC_REL14_BRNTAKEN
+	      || r_type == elfcpp::R_POWERPC_ADDR24
+	      || r_type == elfcpp::R_POWERPC_ADDR14
+	      || r_type == elfcpp::R_POWERPC_ADDR14_BRTAKEN
+	      || r_type == elfcpp::R_POWERPC_ADDR14_BRNTAKEN);
+    }
+
    private:
     // Do a TLS relocation.
     inline void
@@ -460,8 +540,8 @@ Target::Target_info Target_powerpc<32, t
   0x10000000,		// default_text_segment_address
   64 * 1024,		// abi_pagesize (overridable by -z max-page-size)
   4 * 1024,		// common_pagesize (overridable by -z common-page-size)
-  false,                // isolate_execinstr
-  0,                    // rosegment_gap
+  false,		// isolate_execinstr
+  0,			// rosegment_gap
   elfcpp::SHN_UNDEF,	// small_common_shndx
   elfcpp::SHN_UNDEF,	// large_common_shndx
   0,			// small_common_section_flags
@@ -486,8 +566,8 @@ Target::Target_info Target_powerpc<32, f
   0x10000000,		// default_text_segment_address
   64 * 1024,		// abi_pagesize (overridable by -z max-page-size)
   4 * 1024,		// common_pagesize (overridable by -z common-page-size)
-  false,                // isolate_execinstr
-  0,                    // rosegment_gap
+  false,		// isolate_execinstr
+  0,			// rosegment_gap
   elfcpp::SHN_UNDEF,	// small_common_shndx
   elfcpp::SHN_UNDEF,	// large_common_shndx
   0,			// small_common_section_flags
@@ -512,8 +592,8 @@ Target::Target_info Target_powerpc<64, t
   0x10000000,		// default_text_segment_address
   64 * 1024,		// abi_pagesize (overridable by -z max-page-size)
   8 * 1024,		// common_pagesize (overridable by -z common-page-size)
-  false,                // isolate_execinstr
-  0,                    // rosegment_gap
+  false,		// isolate_execinstr
+  0,			// rosegment_gap
   elfcpp::SHN_UNDEF,	// small_common_shndx
   elfcpp::SHN_UNDEF,	// large_common_shndx
   0,			// small_common_section_flags
@@ -538,8 +618,8 @@ Target::Target_info Target_powerpc<64, f
   0x10000000,		// default_text_segment_address
   64 * 1024,		// abi_pagesize (overridable by -z max-page-size)
   8 * 1024,		// common_pagesize (overridable by -z common-page-size)
-  false,                // isolate_execinstr
-  0,                    // rosegment_gap
+  false,		// isolate_execinstr
+  0,			// rosegment_gap
   elfcpp::SHN_UNDEF,	// small_common_shndx
   elfcpp::SHN_UNDEF,	// large_common_shndx
   0,			// small_common_section_flags
@@ -656,9 +736,7 @@ public:
     This::template rela<16>(view, 16, 0xffff, value, addend);
   }
 
-  // R_POWERPC_ADDR16_HA: Same as R_POWERPC_ADDR16_HI except that if the
-  //                      final value of the low 16 bits of the
-  //                      relocation is negative, add one.
+  // R_POWERPC_ADDR16_HA: ((Symbol + Addend + 0x8000) >> 16) & 0xffff
   static inline void
   addr16_ha(unsigned char* view,
 	    typename elfcpp::Elf_types<size>::Elf_Addr value,
@@ -693,9 +771,7 @@ public:
     This::template rela<16>(view, 16, 0xffff, value - address, addend);
   }
 
-  // R_POWERPC_REL16_HA: Same as R_POWERPC_REL16_HI except that if the
-  //                 final value of the low 16 bits of the
-  //                 relocation is negative, add one.
+  // R_POWERPC_REL16_HA: ((Symbol + Addend + 0x8000 - Address) >> 16) & 0xffff
   static inline void
   rel16_ha(unsigned char* view,
 	   typename elfcpp::Elf_types<size>::Elf_Addr value,
@@ -706,30 +782,95 @@ public:
   }
 };
 
-// Stash away the index of .got2 in a relocatable object, if such
-// a section exists.
+// Stash away the index of .got2 or .opd in a relocatable object, if
+// such a section exists.
 
 template<int size, bool big_endian>
 bool
 Powerpc_relobj<size, big_endian>::do_find_special_sections(
     Read_symbols_data* sd)
 {
-  if (size == 32)
+  const unsigned char* const pshdrs = sd->section_headers->data();
+  const unsigned char* namesu = sd->section_names->data();
+  const char* names = reinterpret_cast<const char*>(namesu);
+  section_size_type names_size = sd->section_names_size;
+  const unsigned char* s;
+
+  s = this->find_shdr(pshdrs, size == 32 ? ".got2" : ".opd",
+		      names, names_size, NULL);
+  if (s != NULL)
     {
-      const unsigned char* const pshdrs = sd->section_headers->data();
-      const unsigned char* namesu = sd->section_names->data();
-      const char* names = reinterpret_cast<const char*>(namesu);
-      section_size_type names_size = sd->section_names_size;
-      const unsigned char* s;
+      unsigned int ndx = (s - pshdrs) / elfcpp::Elf_sizes<size>::shdr_size;
+      this->special_ = ndx;
+    }
+  return Sized_relobj_file<size, big_endian>::do_find_special_sections(sd);
+}
 
-      s = this->find_shdr(pshdrs, ".got2", names, names_size, NULL);
-      if (s != NULL)
-	{
-	  unsigned int ndx = (s - pshdrs) / elfcpp::Elf_sizes<size>::shdr_size;
-	  this->got2_section_ = ndx;
+// Examine .rela.opd to build info about function entry points.
+
+template<int size, bool big_endian>
+void
+Powerpc_relobj<size, big_endian>::scan_opd_relocs(
+    size_t reloc_count,
+    const unsigned char* prelocs,
+    const unsigned char* plocal_syms)
+{
+  if (size == 64)
+    {
+      typedef typename Reloc_types<elfcpp::SHT_RELA, size, big_endian>::Reloc
+	Reltype;
+      const int reloc_size
+	= Reloc_types<elfcpp::SHT_RELA, size, big_endian>::reloc_size;
+      const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
+
+      for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
+	{
+	  Reltype reloc(prelocs);
+	  typename elfcpp::Elf_types<size>::Elf_WXword r_info
+	    = reloc.get_r_info();
+	  unsigned int r_type = elfcpp::elf_r_type<size>(r_info);
+	  if (r_type == elfcpp::R_PPC64_ADDR64)
+	    {
+	      unsigned int r_sym = elfcpp::elf_r_sym<size>(r_info);
+	      typename elfcpp::Elf_types<size>::Elf_Addr value;
+	      bool is_ordinary;
+	      unsigned int shndx;
+	      if (r_sym < this->local_symbol_count())
+		{
+		  typename elfcpp::Sym<size, big_endian>
+		    lsym(plocal_syms + r_sym * sym_size);
+		  shndx = lsym.get_st_shndx();
+		  shndx = this->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
+		  value = lsym.get_st_value();
+		}
+	      else
+		shndx = this->symbol_section_and_value(r_sym, &value,
+						       &is_ordinary);
+	      this->set_opd_ent(reloc.get_r_offset(), shndx,
+				value + reloc.get_r_addend());
+	    }
 	}
     }
-  return Sized_relobj_file<size, big_endian>::do_find_special_sections(sd);
+}
+
+template<int size, bool big_endian>
+void
+Powerpc_relobj<size, big_endian>::do_read_relocs(Read_relocs_data* rd)
+{
+  Sized_relobj_file<size, big_endian>::do_read_relocs(rd);
+  if (size == 64)
+    {
+      for (Read_relocs_data::Relocs_list::iterator p = rd->relocs.begin();
+	   p != rd->relocs.end();
+	   ++p)
+	if (p->data_shndx == this->opd_shndx())
+	  {
+	    this->init_opd(this->section_size(this->opd_shndx()));
+	    this->scan_opd_relocs(p->reloc_count, p->contents->data(),
+				  rd->local_symbols->data());
+	    break;
+	  }
+    }
 }
 
 // Set up PowerPC target specific relobj.
@@ -745,21 +886,20 @@ Target_powerpc<size, big_endian>::do_mak
   if (et == elfcpp::ET_REL)
     {
       Powerpc_relobj<size, big_endian>* obj =
-        new Powerpc_relobj<size, big_endian>(name, input_file, offset, ehdr);
+	new Powerpc_relobj<size, big_endian>(name, input_file, offset, ehdr);
       obj->setup();
       return obj;
     }
   else if (et == elfcpp::ET_DYN)
     {
       Sized_dynobj<size, big_endian>* obj =
-        new Sized_dynobj<size, big_endian>(name, input_file, offset, ehdr);
+	new Sized_dynobj<size, big_endian>(name, input_file, offset, ehdr);
       obj->setup();
       return obj;
     }
   else
     {
-      gold_error(_("%s: unsupported ELF file type %d"),
-                 name.c_str(), et);
+      gold_error(_("%s: unsupported ELF file type %d"), name.c_str(), et);
       return NULL;
     }
 }
@@ -1013,45 +1153,48 @@ Output_data_plt_powerpc<size, big_endian
     }
 }
 
-static const uint32_t addis_11_11       = 0x3d6b0000;
-static const uint32_t addis_11_30       = 0x3d7e0000;
-static const uint32_t addis_12_12       = 0x3d8c0000;
-static const uint32_t addi_11_11        = 0x396b0000;
-static const uint32_t add_0_11_11       = 0x7c0b5a14;
-static const uint32_t add_11_0_11       = 0x7d605a14;
-static const uint32_t b                 = 0x48000000;
-static const uint32_t bcl_20_31         = 0x429f0005;
-static const uint32_t bctr              = 0x4e800420;
-static const uint32_t blrl              = 0x4e800021;
-static const uint32_t lis_11            = 0x3d600000;
-static const uint32_t lis_12            = 0x3d800000;
-static const uint32_t lwzu_0_12         = 0x840c0000;
-static const uint32_t lwz_0_12          = 0x800c0000;
-static const uint32_t lwz_11_11         = 0x816b0000;
-static const uint32_t lwz_11_30         = 0x817e0000;
-static const uint32_t lwz_12_12         = 0x818c0000;
-static const uint32_t mflr_0            = 0x7c0802a6;
-static const uint32_t mflr_12           = 0x7d8802a6;
-static const uint32_t mtctr_0           = 0x7c0903a6;
-static const uint32_t mtctr_11          = 0x7d6903a6;
-static const uint32_t mtlr_0            = 0x7c0803a6;
-static const uint32_t nop               = 0x60000000;
-static const uint32_t sub_11_11_12      = 0x7d6c5850;
-static const uint32_t addis_12_2        = 0x3d820000;
-static const uint32_t std_2_1           = 0xf8410000;
-static const uint32_t ld_11_12          = 0xe96c0000;
-static const uint32_t ld_2_12           = 0xe84c0000;
-static const uint32_t addi_12_12        = 0x398c0000;
-static const uint32_t ld_11_2           = 0xe9620000;
-static const uint32_t addi_2_2          = 0x38420000;
-static const uint32_t ld_2_2            = 0xe8420000;
-static const uint32_t mflr_11           = 0x7d6802a6;
-static const uint32_t ld_2_11           = 0xe84b0000;
-static const uint32_t mtlr_12           = 0x7d8803a6;
-static const uint32_t add_12_2_11       = 0x7d825a14;
-static const uint32_t li_0_0            = 0x38000000;
-static const uint32_t lis_0_0           = 0x3c000000;
-static const uint32_t ori_0_0_0         = 0x60000000;
+static const uint32_t addis_11_11	= 0x3d6b0000;
+static const uint32_t addis_11_30	= 0x3d7e0000;
+static const uint32_t addis_12_12	= 0x3d8c0000;
+static const uint32_t addi_11_11	= 0x396b0000;
+static const uint32_t add_0_11_11	= 0x7c0b5a14;
+static const uint32_t add_11_0_11	= 0x7d605a14;
+static const uint32_t b			= 0x48000000;
+static const uint32_t bcl_20_31		= 0x429f0005;
+static const uint32_t bctr		= 0x4e800420;
+static const uint32_t blrl		= 0x4e800021;
+static const uint32_t lis_11		= 0x3d600000;
+static const uint32_t lis_12		= 0x3d800000;
+static const uint32_t lwzu_0_12		= 0x840c0000;
+static const uint32_t lwz_0_12		= 0x800c0000;
+static const uint32_t lwz_11_11		= 0x816b0000;
+static const uint32_t lwz_11_30		= 0x817e0000;
+static const uint32_t lwz_12_12		= 0x818c0000;
+static const uint32_t mflr_0		= 0x7c0802a6;
+static const uint32_t mflr_12		= 0x7d8802a6;
+static const uint32_t mtctr_0		= 0x7c0903a6;
+static const uint32_t mtctr_11		= 0x7d6903a6;
+static const uint32_t mtlr_0		= 0x7c0803a6;
+static const uint32_t nop		= 0x60000000;
+static const uint32_t sub_11_11_12	= 0x7d6c5850;
+static const uint32_t addis_12_2	= 0x3d820000;
+static const uint32_t std_2_1		= 0xf8410000;
+static const uint32_t ld_2_1		= 0xe8410000;
+static const uint32_t ld_11_12		= 0xe96c0000;
+static const uint32_t ld_2_12		= 0xe84c0000;
+static const uint32_t addi_12_12	= 0x398c0000;
+static const uint32_t ld_11_2		= 0xe9620000;
+static const uint32_t addi_2_2		= 0x38420000;
+static const uint32_t ld_2_2		= 0xe8420000;
+static const uint32_t mflr_11		= 0x7d6802a6;
+static const uint32_t ld_2_11		= 0xe84b0000;
+static const uint32_t mtlr_12		= 0x7d8803a6;
+static const uint32_t add_12_2_11	= 0x7d825a14;
+static const uint32_t li_0_0		= 0x38000000;
+static const uint32_t lis_0_0		= 0x3c000000;
+static const uint32_t ori_0_0_0		= 0x60000000;
+static const uint32_t cror_15_15_15	= 0x4def7b82;
+static const uint32_t cror_31_31_31	= 0x4ffffb82;
 
 // Write out the PLT.
 
@@ -1149,6 +1292,12 @@ class Output_data_glink : public Output_
     return this->pltresolve_;
   }
 
+  int
+  pltresolve_size() const
+  {
+    return this->pltresolve_size_;
+  }
+
  protected:
   // Write to a map file.
   void
@@ -1156,7 +1305,7 @@ class Output_data_glink : public Output_
   { mapfile->print_output_data(this, _("** glink")); }
 
  private:
-  static const int pltresolve_size = 16*4;
+  static const int pltresolve_size_ = 16*4;
 
   void
   set_final_data_size();
@@ -1171,7 +1320,7 @@ class Output_data_glink : public Output_
     Glink_sym_ent(const Symbol* sym,
 		  const elfcpp::Rela<size, big_endian>& reloc,
 		  const Sized_relobj<size, big_endian>* object)
-      : sym_(sym), object_(0), addend_(0)
+      : sym_(sym), addend_(0), object_(0)
     {
       if (size != 32)
 	this->addend_ = reloc.get_r_addend();
@@ -1185,16 +1334,16 @@ class Output_data_glink : public Output_
 	}
     }
 
-    const Symbol* sym_;
-    const Sized_relobj<size, big_endian>* object_;
-    unsigned int addend_;
-
     bool operator==(const Glink_sym_ent& that) const
     {
       return (this->sym_ == that.sym_
 	      && this->object_ == that.object_
 	      && this->addend_ == that.addend_);
     }
+
+    const Symbol* sym_;
+    unsigned int addend_;
+    const Sized_relobj<size, big_endian>* object_;
   };
 
   class Glink_sym_ent_hash
@@ -1276,13 +1425,13 @@ Output_data_glink<size, big_endian>::set
 	  total += 4 * (count - 1);
 
 	  total += -total & 15;
-	  total += this->pltresolve_size;
+	  total += this->pltresolve_size_;
 	}
       else
 	{
 	  total *= 32;
 	  this->pltresolve_ = total;
-	  total += this->pltresolve_size;
+	  total += this->pltresolve_size_;
 
 	  // space for branch table
 	  total += 8 * count;
@@ -1314,7 +1463,7 @@ ha(uint32_t a)
 
 template<bool big_endian>
 static inline void
-write_insn(unsigned char *p, uint32_t v)
+write_insn(unsigned char* p, uint32_t v)
 {
   elfcpp::Swap<32, big_endian>::writeval(p, v);
 }
@@ -1329,19 +1478,21 @@ Output_data_glink<size, big_endian>::do_
   const section_size_type oview_size =
     convert_to_section_size_type(this->data_size());
   unsigned char* const oview = of->get_output_view(off, oview_size);
-  unsigned char *p;
+  unsigned char* p;
 
   // The base address of the .plt section.
   uint32_t plt_base = this->targ_->plt_section()->address();
 
   // The address of _GLOBAL_OFFSET_TABLE_.
-  const Output_data_got_powerpc<size, big_endian> *got;
+  const Output_data_got_powerpc<size, big_endian>* got;
   typename elfcpp::Elf_types<size>::Elf_Addr g_o_t;
   got = this->targ_->got_section();
-  g_o_t = got->address() + got->g_o_t();
 
   if (size == 64)
     {
+      const unsigned int toc_base_offset = 0x8000;
+      g_o_t = got->output_section()->address() + toc_base_offset;
+
       // Write out call stubs.
       typename Glink_entries::const_iterator g;
       for (g = this->glink_entries_.begin();
@@ -1407,7 +1558,7 @@ Output_data_glink<size, big_endian>::do_
       write_insn<big_endian>(p, mtctr_11),			p += 4;
       write_insn<big_endian>(p, ld_11_12 + 16),			p += 4;
       write_insn<big_endian>(p, bctr),				p += 4;
-      while (p < oview + this->pltresolve_ + this->pltresolve_size)
+      while (p < oview + this->pltresolve_ + this->pltresolve_size_)
 	write_insn<big_endian>(p, nop), p += 4;
 
       // Write lazy link call stubs.
@@ -1423,13 +1574,15 @@ Output_data_glink<size, big_endian>::do_
 	      write_insn<big_endian>(p, lis_0_0 + hi(indx)),		p += 4;
 	      write_insn<big_endian>(p, ori_0_0_0 + l(indx)),		p += 4;
 	    }
-	  uint16_t branch_off = this->pltresolve_ + 8 - (p - oview);
+	  uint32_t branch_off = this->pltresolve_ + 8 - (p - oview);
 	  write_insn<big_endian>(p, b + (branch_off & 0x3fffffc)),	p += 4;
 	  indx++;
 	}
     }
   else
     {
+      g_o_t = got->address() + got->g_o_t();
+
       // Write out call stubs.
       typename Glink_entries::const_iterator g;
       for (g = this->glink_entries_.begin();
@@ -1480,8 +1633,8 @@ Output_data_glink<size, big_endian>::do_
 
       // Write out pltresolve branch table.
       p = oview + this->pltresolve_;
-      unsigned int the_end = oview_size - this->pltresolve_size;
-      unsigned char *end_p = oview + the_end;
+      unsigned int the_end = oview_size - this->pltresolve_size_;
+      unsigned char* end_p = oview + the_end;
       while (p < end_p - 8 * 4)
 	write_insn<big_endian>(p, b + end_p - p), p += 4;
       while (p < end_p)
@@ -1852,8 +2005,10 @@ Target_powerpc<size, big_endian>::Scan::
 
     case elfcpp::R_PPC64_ADDR64:
     case elfcpp::R_POWERPC_ADDR32:
-    case elfcpp::R_POWERPC_ADDR16_HA:
+    case elfcpp::R_POWERPC_ADDR16:
     case elfcpp::R_POWERPC_ADDR16_LO:
+    case elfcpp::R_POWERPC_ADDR16_HI:
+    case elfcpp::R_POWERPC_ADDR16_HA:
       // If building a shared library (or a position-independent
       // executable), we need to create a dynamic relocation for
       // this location.
@@ -1893,8 +2048,8 @@ Target_powerpc<size, big_endian>::Scan::
     case elfcpp::R_POWERPC_GOT16_HI:
     case elfcpp::R_POWERPC_GOT16_HA:
       {
-        // The symbol requires a GOT entry.
-        Output_data_got_powerpc<size, big_endian>* got;
+	// The symbol requires a GOT entry.
+	Output_data_got_powerpc<size, big_endian>* got;
 	unsigned int r_sym;
 
 	got = target->got_section(symtab, layout);
@@ -1985,16 +2140,16 @@ Target_powerpc<size, big_endian>::Scan::
     case elfcpp::R_PPC_LOCAL24PC:
       break;
 
+    case elfcpp::R_PPC64_ADDR64:
+    case elfcpp::R_POWERPC_ADDR32:
     case elfcpp::R_POWERPC_ADDR16:
     case elfcpp::R_POWERPC_ADDR16_LO:
     case elfcpp::R_POWERPC_ADDR16_HI:
     case elfcpp::R_POWERPC_ADDR16_HA:
-    case elfcpp::R_POWERPC_ADDR32:
-    case elfcpp::R_PPC64_ADDR64:
       {
-        // Make a PLT entry if necessary.
-        if (gsym->needs_plt_entry())
-          {
+	// Make a PLT entry if necessary.
+	if (gsym->needs_plt_entry())
+	  {
 	    target->make_plt_entry(layout, gsym, reloc, 0);
 	    // Since this is not a PC-relative relocation, we may be
 	    // taking the address of a function. In that case we need to
@@ -2003,16 +2158,16 @@ Target_powerpc<size, big_endian>::Scan::
 	    if (size == 32
 		&& gsym->is_from_dynobj() && !parameters->options().shared())
 	      gsym->set_needs_dynsym_value();
-          }
-        // Make a dynamic relocation if necessary.
-        if (gsym->needs_dynamic_reloc(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 if ((r_type == elfcpp::R_POWERPC_ADDR32
+	  }
+	// Make a dynamic relocation if necessary.
+	if (gsym->needs_dynamic_reloc(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 if ((r_type == elfcpp::R_POWERPC_ADDR32
 		      || r_type == elfcpp::R_PPC64_ADDR64)
 		     && gsym->can_use_relative_reloc(false))
 	      {
@@ -2086,8 +2241,8 @@ Target_powerpc<size, big_endian>::Scan::
     case elfcpp::R_POWERPC_GOT16_HI:
     case elfcpp::R_POWERPC_GOT16_HA:
       {
-        // The symbol requires a GOT entry.
-        Output_data_got_powerpc<size, big_endian>* got;
+	// The symbol requires a GOT entry.
+	Output_data_got_powerpc<size, big_endian>* got;
 
 	got = target->got_section(symtab, layout);
 	if (gsym->final_value_is_known())
@@ -2261,13 +2416,21 @@ Target_powerpc<size, big_endian>::do_fin
   layout->add_target_dynamic_tags(false, this->plt_, rel_plt,
 				  this->rela_dyn_, true, size == 32);
 
+  Output_data_dynamic* odyn = layout->dynamic_data();
   if (size == 32)
     {
       this->got_->finalize_data_size();
-      Output_data_dynamic* odyn = layout->dynamic_data();
       odyn->add_section_plus_offset(elfcpp::DT_PPC_GOT,
 				    this->got_, this->got_->g_o_t());
     }
+  else
+    {
+      this->glink_->finalize_data_size();
+      odyn->add_section_plus_offset(elfcpp::DT_PPC64_GLINK,
+				    this->glink_,
+				    (this->glink_->pltresolve()
+				     + this->glink_->pltresolve_size() - 32));
+    }
 
   // Emit any relocs we saved in an attempt to avoid generating COPY
   // relocs.
@@ -2290,13 +2453,13 @@ Target_powerpc<size, big_endian>::Reloca
     const Symbol_value<size>* psymval,
     unsigned char* view,
     typename elfcpp::Elf_types<size>::Elf_Addr address,
-    section_size_type /* view_size */)
+    section_size_type view_size)
 {
   const unsigned int toc_base_offset = 0x8000;
   typedef Powerpc_relocate_functions<size, big_endian> Reloc;
   const Powerpc_relobj<size, big_endian>* const object
     = static_cast<const Powerpc_relobj<size, big_endian>*>(relinfo->object);
-  elfcpp::Elf_Xword value;
+  typename elfcpp::Elf_types<size>::Elf_Addr value;
 
   if (r_type == elfcpp::R_POWERPC_GOT16
       || r_type == elfcpp::R_POWERPC_GOT16_LO
@@ -2320,7 +2483,8 @@ Target_powerpc<size, big_endian>::Reloca
     }
   else if (r_type == elfcpp::R_PPC64_TOC)
     {
-      value = target->got_section()->address() + toc_base_offset;
+      value = (target->got_section()->output_section()->address()
+	       + toc_base_offset);
     }
   else if (gsym != NULL
 	   && (r_type == elfcpp::R_POWERPC_REL24
@@ -2332,6 +2496,36 @@ Target_powerpc<size, big_endian>::Reloca
       glink = target->glink_section();
       unsigned int glink_index = glink->find_entry(gsym, rela, object);
       value = glink->address() + glink_index * glink->glink_entry_size();
+      if (size == 64)
+	{
+	  typedef typename elfcpp::Swap<32, big_endian>::Valtype Valtype;
+	  Valtype* wv = reinterpret_cast<Valtype*>(view);
+	  bool can_plt_call = false;
+	  if (rela.get_r_offset() + 8 <= view_size)
+	    {
+	      Valtype insn2 = elfcpp::Swap<32, big_endian>::readval(wv + 1);
+	      if (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)
+	    {
+	      if (parameters->options().output_is_executable())
+		{
+		  Valtype insn = elfcpp::Swap<32, big_endian>::readval(wv);
+		  if ((insn & 1) == 0)
+		    can_plt_call = true;
+		}
+	      else if (strcmp(gsym->name(), ".__libc_start_main") == 0)
+		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"));
+	}
     }
   else
     {
@@ -2339,6 +2533,25 @@ Target_powerpc<size, big_endian>::Reloca
       if (r_type != elfcpp::R_PPC_PLTREL24)
 	addend = rela.get_r_addend();
       value = psymval->value(object, addend);
+      if (size == 64 && this->is_branch_reloc(r_type))
+	{
+	  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();
+	  typename elfcpp::Elf_types<size>::Elf_Addr opd_addr
+	    = (symobj->output_section(shndx)->address()
+	       + symobj->output_section_offset(shndx));
+	  if (value >= opd_addr
+	      && value < opd_addr + symobj->section_size(shndx))
+	    {
+	      symobj->get_opd_ent(value - opd_addr, &shndx, &value);
+	      value += (symobj->output_section(shndx)->address()
+			+ symobj->output_section_offset(shndx));
+	    }
+	}
     }
 
   switch (r_type)
@@ -2350,7 +2563,8 @@ Target_powerpc<size, big_endian>::Reloca
     case elfcpp::R_PPC64_TOC16_DS:
     case elfcpp::R_PPC64_TOC16_LO_DS:
       // Subtract the TOC base address.
-      value -= target->got_section()->address() + toc_base_offset;
+      value -= (target->got_section()->output_section()->address()
+		+ toc_base_offset);
       break;
 
     case elfcpp::R_POWERPC_SECTOFF:
@@ -2716,13 +2930,13 @@ Target_powerpc<size, big_endian>::reloca
 	new_offset = offset + offset_in_output_section;
       else
 	{
-          section_offset_type sot_offset =
-              convert_types<section_offset_type, Address>(offset);
+	  section_offset_type sot_offset =
+	    convert_types<section_offset_type, Address>(offset);
 	  section_offset_type new_sot_offset =
-              output_section->output_offset(object, relinfo->data_shndx,
-                                            sot_offset);
+	    output_section->output_offset(object, relinfo->data_shndx,
+					  sot_offset);
 	  gold_assert(new_sot_offset != -1);
-          new_offset = new_sot_offset;
+	  new_offset = new_sot_offset;
 	}
 
       reloc_write.put_r_offset(new_offset);
Index: gold/symtab.h
===================================================================
RCS file: /cvs/src/src/gold/symtab.h,v
retrieving revision 1.127
diff -u -p -r1.127 symtab.h
--- gold/symtab.h	31 Oct 2011 21:36:54 -0000	1.127
+++ gold/symtab.h	16 Aug 2012 12:03:01 -0000
@@ -62,7 +62,7 @@ class Garbage_collection;
 class Icf;
 
 // The base class of an entry in the symbol table.  The symbol table
-// can have a lot of entries, so we don't want this class to big.
+// can have a lot of entries, so we don't want this class too big.
 // Size dependent fields can be found in the template class
 // Sized_symbol.  Targets may support their own derived classes.
 


-- 
Alan Modra
Australia Development Lab, IBM


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