PR 10893

	* i386.cc (class Output_data_plt_i386): Update declarations.
	Define Global_ifunc and Local_ifunc types.  Add global_ifuncs_ and
	local_ifuncs_ fields.
	(Target_i386::do_plt_section_for_global): New function.
	(Target_i386::do_plt_section_for_local): New function.
	(Output_data_plt_i386::Output_data_plt_i386): Add symtab
	parameter; change all callers.  Initialize global_ifuncs_ and
	local_ifuncs_.  If doing a static link define __rel_iplt_start and
	__rel_iplt_end.
	(Output_data_plt_i386::add_entry): Handle IFUNC symbols.
	(Output_data_plt_i386::add_local_ifunc_entry): New function.
	(Output_data_plt_i386::do_write): Fix GOT entries for IFUNC
	symbols.
	(Target_i386::make_plt_section): New function, broken out of
	make_plt_entry.  Set sh_info field of .rel.plt to point to .plt.
	(Target_i386::make_plt_entry): Call make_plt_section.
	(Target_i386::make_local_ifunc_plt_entry): New function.
	(Target_i386::Scan::reloc_needs_iplt_for_ifunc): New function.
	(Target_i386::Scan::local): Handle IFUNC symbols.  Add
	R_386_IRELATIVE to switch.
	(Target_i386::Scan::global): Likewise.
	(Target_i386::Relocate::relocate): Likewise.
	(Target_i386::Relocatable_size_for_reloc): Add R_386_IRELATIVE to
	switch.
	* x86_64.cc (class Output_data_plt_x86_64): Update declarations.
	(Target_x86_64::do_plt_section_for_global): New function.
	(Target_x86_64::do_plt_section_for_local): New function.
	(Output_data_plt_x86_64::Output_data_plt_x86_64): Add symtab
	parameter; change all callers.  If doing a static link define
	__rela_iplt_start and __rela_iplt_end.
	(Output_data_plt_x86_64::add_entry): Handle IFUNC symbols.
	(Output_data_plt_x86_64::add_local_ifunc_entry): New function.
	(Target_x86_64::make_plt_section): Set sh_info field of .rel.plt
	to point to .plt.
	(Target_x86_64::make_local_ifunc_plt_entry): New function.
	(Target_x86_64::Scan::check_non_pic): Add R_X86_64_IRELATIVE to
	switch.
	(Target_x86_64::Scan::reloc_needs_iplt_for_ifunc): New function.
	(Target_x86_64::Scan::local): Handle IFUNC symbols.  Add
	R_X86_64_IRELATIVE to switch.
	(Target_x86_64::Scan::global): Likewise.
	(Target_x86_64::Relocate::relocate): Likewise.
	(Target_x86_64::Relocatable_size_for_reloc): Add R_X86_64_IRELATIVE to
	switch.
	* target.h (class Target): Add plt_section_for_global and
	plt_section_for_local functions.  Add do_plt_section_for_global
	and do_plt_section_for_local virtual functions.
	* symtab.h (Symbol::needs_plt_entry): Handle IFUNC symbol.  Add
	clarifying comments.
	(Symbol::use_plt_offset): Handle IFUNC symbol.
	* object.cc (Sized_relobj::Sized_relobj): Initialize
	local_plt_offsets_.
	(Sized_relobj::local_has_plt_offset): New function.
	(Sized_relobj::local_plt_offset): New function.
	(Sized_relobj::set_local_plt_offset): New function.
	(Sized_relobj::do_count): Handle IFUNC symbol.
	* object.h (class Symbol_value): Add is_ifunc_symbol_ field.  Take
	a bit away from input_shndx_ field.  Add set_is_func_symbol and
	is_ifunc_symbol functions.
	(class Sized_relobj): Update declarations.  Remove Tls_got_entry
	and Local_tls_got_offsets.  Define Local_plt_offsets.  Add
	local_plt_offsets_ field.
	(Sized_relobj::clear_local_symbols): Clear local_plt_offsets_.
	* output.h (class Output_section_data): Add non-const
	output_section function.
	(class Output_data_got): Update declarations.
	(class Output_data_got::Got_entry): Add use_plt_offset_ field.
	Add use_plt_offset parameter to global and local constructors.
	Change all callers.  Change local_sym_index_ field to 31 bits.
	Change GSYM_CODE and CONSTANT_CODE accordingly.
	* output.cc (Output_data_reloc_base::do_adjust_output_section): If
	doing a static link don't set sh_link field.
	(Output_data_got::Got_entry::write): Use PLT offset if
	appropriate.
	(Output_data_got::add_global_plt): New function.
	(Output_data_got::add_local_plt): New function.
	* target-reloc.h (relocate_section): Handle IFUNC symbol.
	* defstd.cc (in_section): Remove entries for __rel_iplt_start,
	__rel_iplt_end, __rela_iplt_start, and __rela_iplt_end.
	* configure.ac: Set IFUNC automake conditional for glibc >= 2.11.
	* testsuite/Makefile.am: Add a bunch of IFUNC tests, all within
	IFUNC conditional.
	* testsuite/ifunc-sel.h: New file.
	* testsuite/ifuncmain1.c: New file.
	* testsuite/ifuncmain1vis.c: New file.
	* testsuite/ifuncmod1.c: New file.
	* testsuite/ifuncdep2.c: New file.
	* testsuite/ifuncmain2.c: New file.
	* testsuite/ifuncmain3.c: New file.
	* testsuite/ifuncmod3.c: New file.
	* testsuite/ifuncmain4.c: New file.
	* testsuite/ifuncmain5.c: New file.
	* testsuite/ifuncmod5.c: New file.
	* testsuite/ifuncmain6pie.c: New file.
	* testsuite/ifuncmod6.c: New file.
	* testsuite/ifuncmain7.c: New file.
	* configure, testsuite/Makefile.in: Rebuild.

1 files changed, 34 insertions, 17 deletions

diff --git a/gold/object.h b/gold/object.h
index 94ad643..3412aec 100644
--- a/gold/object.h
+++ b/gold/object.h
@@ -39,6 +39,7 @@ class General_options;
 class Task;
 class Cref;
 class Layout;
+class Output_data;
 class Output_section;
 class Output_file;
 class Output_symtab_xindex;
@@ -1151,7 +1152,7 @@ class Symbol_value
   Symbol_value()
     : output_symtab_index_(0), output_dynsym_index_(-1U), input_shndx_(0),
       is_ordinary_shndx_(false), is_section_symbol_(false),
-      is_tls_symbol_(false), has_output_value_(true)
+      is_tls_symbol_(false), is_ifunc_symbol_(false), has_output_value_(true)
   { this->u_.value = 0; }
 
   // Get the value of this symbol.  OBJECT is the object in which this
@@ -1364,11 +1365,21 @@ class Symbol_value
   set_is_tls_symbol()
   { this->is_tls_symbol_ = true; }
 
-  // Return TRUE if this is a TLS symbol.
+  // Return true if this is a TLS symbol.
   bool
   is_tls_symbol() const
   { return this->is_tls_symbol_; }
 
+  // Record that this is an IFUNC symbol.
+  void
+  set_is_ifunc_symbol()
+  { this->is_ifunc_symbol_ = true; }
+
+  // Return true if this is an IFUNC symbol.
+  bool
+  is_ifunc_symbol() const
+  { return this->is_ifunc_symbol_; }
+
  private:
   // The index of this local symbol in the output symbol table.  This
   // will be 0 if no value has been assigned yet, and the symbol may
@@ -1381,7 +1392,7 @@ class Symbol_value
   unsigned int output_dynsym_index_;
   // The section index in the input file in which this symbol is
   // defined.
-  unsigned int input_shndx_ : 28;
+  unsigned int input_shndx_ : 27;
   // Whether the section index is an ordinary index, not a special
   // value.
   bool is_ordinary_shndx_ : 1;
@@ -1389,6 +1400,8 @@ class Symbol_value
   bool is_section_symbol_ : 1;
   // Whether this is a STT_TLS symbol.
   bool is_tls_symbol_ : 1;
+  // Whether this is a STT_GNU_IFUNC symbol.
+  bool is_ifunc_symbol_ : 1;
   // Whether this symbol has a value for the output file.  This is
   // normally set to true during Layout::finalize, by
   // finalize_local_symbols.  It will be false for a section symbol in
@@ -1692,6 +1705,19 @@ class Sized_relobj : public Relobj
     return p->second;
   }
 
+  // Return whether the local symbol SYMNDX has a PLT offset.
+  bool
+  local_has_plt_offset(unsigned int symndx) const;
+
+  // Return the PLT offset for a local symbol.  It is an error to call
+  // this if it doesn't have one.
+  unsigned int
+  local_plt_offset(unsigned int symndx) const;
+
+  // Set the PLT offset of the local symbol SYMNDX.
+  void
+  set_local_plt_offset(unsigned int symndx, unsigned int plt_offset);
+
   // Get the offset of input section SHNDX within its output section.
   // This is -1 if the input section requires a special mapping, such
   // as a merge section.  The output section can be found in the
@@ -2108,6 +2134,7 @@ class Sized_relobj : public Relobj
   {
     this->local_values_.clear();
     this->local_got_offsets_.clear();
+    this->local_plt_offsets_.clear();
   }
 
   // Record a mapping from discarded section SHNDX to the corresponding
@@ -2139,20 +2166,8 @@ class Sized_relobj : public Relobj
   // for tp-relative offsets for TLS symbols.
   typedef Unordered_map<unsigned int, Got_offset_list*> Local_got_offsets;
 
-  // The TLS GOT offsets of local symbols. The map stores the offsets
-  // for either a single GOT entry that holds the module index of a TLS
-  // symbol, or a pair of GOT entries containing the module index and
-  // dtv-relative offset.
-  struct Tls_got_entry
-  {
-    Tls_got_entry(int got_offset, bool have_pair)
-      : got_offset_(got_offset),
-        have_pair_(have_pair)
-    { }
-    int got_offset_;
-    bool have_pair_;
-  };
-  typedef Unordered_map<unsigned int, Tls_got_entry> Local_tls_got_offsets;
+  // The PLT offsets of local symbols.
+  typedef Unordered_map<unsigned int, unsigned int> Local_plt_offsets;
 
   // Saved information for sections whose layout was deferred.
   struct Deferred_layout
@@ -2197,6 +2212,8 @@ class Sized_relobj : public Relobj
   // GOT offsets for local non-TLS symbols, and tp-relative offsets
   // for TLS symbols, indexed by symbol number.
   Local_got_offsets local_got_offsets_;
+  // PLT offsets for local symbols.
+  Local_plt_offsets local_plt_offsets_;
   // For each input section, the offset of the input section in its
   // output section.  This is INVALID_ADDRESS if the input section requires a
   // special mapping.