Refactor gold to enable support for MIPS-64 relocation format.

For MIPS-64, the r_info field in the relocation format is
replaced by several individual fields, including r_sym and
r_type. To enable support for this format, I've refactored
target-independent code to remove almost all uses of the r_info
field. (I've left alone a couple of routines used only for
incremental linking, which I can update if/when the MIPS target
adds support for incremental linking.)

For routines that are already templated on a Classify_reloc class
(namely, gc_process_relocs, relocate_section, and
relocate_relocs), I've extended the Classify_reloc interface to
include sh_type (which no longer needs to be a separate template
parameter) as well as get_r_sym() and get_r_type() methods for
extracting the r_sym and r_type fields. For
scan_relocatable_relocs, I've extended the
Default_scan_relocatable_relocs class by converting it to a class
template with Classify_reloc as a template parameter. For the
remaining routines that need to access r_sym, I've added a
virtual Target::get_r_sym() method with an override for the MIPS
target.

In elfcpp, I've added Mips64_rel, etc., accessor classes and
corresponding internal data structures. The MIPS target uses
these new classes within its own Mips_classify_reloc class.
The Mips64_ accessor classes also expose the r_ssym, r_type2,
and r_type3 fields from the relocation.

These changes should be functionally the same for all but the
MIPS target.

elfcpp/
	* elfcpp.h (Mips64_rel, Mips64_rel_write): New classes.
	(Mips64_rela, Mips64_rela_write): New classes.
	* elfcpp_internal.h (Mips64_rel_data, Mips64_rela_data): New structs.

gold/
	* gc.h (get_embedded_addend_size): Remove sh_type parameter.
	(gc_process_relocs): Remove sh_type template parameter.
	Use Classify_reloc to access r_sym, r_type, and r_addend fields.
	* object.h (Sized_relobj_file::split_stack_adjust): Add target
	parameter.
	(Sized_relobj_file::split_stack_adjust_reltype): Likewise.
	* reloc-types.h (Reloc_types::copy_reloc_addend): (SHT_REL and SHT_RELA
	specializations) Remove.
	* reloc.cc (Emit_relocs_strategy): Rename and move to target-reloc.h.
	(Sized_relobj_file::emit_relocs_scan): Call Target::emit_relocs_scan().
	(Sized_relobj_file::emit_relocs_scan_reltype): Remove.
	(Sized_relobj_file::split_stack_adjust): Add target parameter.
	Adjust all callers.
	(Sized_relobj_file::split_stack_adjust_reltype): Likewise. Call
	Target::get_r_sym() to get r_sym field from relocations.
	(Track_relocs::next_symndx): Call Target::get_r_sym().
	* target-reloc.h (scan_relocs): Remove sh_type template parameter;
	add Classify_reloc template parameter.  Use for accessing r_sym and
	r_type.
	(relocate_section): Likewise.
	(Default_classify_reloc): New class (renamed and moved from reloc.cc).
	(Default_scan_relocatable_relocs): Remove sh_type template parameter.
	(Default_scan_relocatable_relocs::Reltype): New typedef.
	(Default_scan_relocatable_relocs::reloc_size): New const.
	(Default_scan_relocatable_relocs::sh_type): New const.
	(Default_scan_relocatable_relocs::get_r_sym): New method.
	(Default_scan_relocatable_relocs::get_r_type): New method.
	(Default_emit_relocs_strategy): New class.
	(scan_relocatable_relocs): Replace sh_type template parameter with
	Scan_relocatable_relocs class.  Use it to access r_sym and r_type
	fields.
	(relocate_relocs): Replace sh_type template parameter with
	Classify_reloc class.  Use it to access r_sym and r_type fields.
	* target.h (Target::is_call_to_non_split): Replace r_type parameter
	with pointer to relocation. Adjust all callers.
	(Target::do_is_call_to_non_split): Likewise.
	(Target::emit_relocs_scan): New virtual method.
	(Sized_target::get_r_sym): New virtual method.
	* target.cc (Target::do_is_call_to_non_split): Replace r_type parameter
	with pointer to relocation.

	* aarch64.cc (Target_aarch64::emit_relocs_scan): New method.
	(Target_aarch64::Relocatable_size_for_reloc): Remove.
	(Target_aarch64::gc_process_relocs): Use Default_classify_reloc.
	(Target_aarch64::scan_relocs): Likewise.
	(Target_aarch64::relocate_section): Likewise.
	(Target_aarch64::Relocatable_size_for_reloc::get_size_for_reloc):
	Remove.
	(Target_aarch64::scan_relocatable_relocs): Use Default_classify_reloc.
	(Target_aarch64::relocate_relocs): Use Default_classify_reloc.
	* arm.cc (Target_arm::Arm_scan_relocatable_relocs): Remove sh_type
	template parameter.
	(Target_arm::emit_relocs_scan): New method.
	(Target_arm::Relocatable_size_for_reloc): Replace with...
	(Target_arm::Classify_reloc): ...this.
	(Target_arm::gc_process_relocs): Use Classify_reloc.
	(Target_arm::scan_relocs): Likewise.
	(Target_arm::relocate_section): Likewise.
	(Target_arm::scan_relocatable_relocs): Likewise.
	(Target_arm::relocate_relocs): Likewise.
	* i386.cc (Target_i386::emit_relocs_scan): New method.
	(Target_i386::Relocatable_size_for_reloc): Replace with...
	(Target_i386::Classify_reloc): ...this.
	(Target_i386::gc_process_relocs): Use Classify_reloc.
	(Target_i386::scan_relocs): Likewise.
	(Target_i386::relocate_section): Likewise.
	(Target_i386::scan_relocatable_relocs): Likewise.
	(Target_i386::relocate_relocs): Likewise.
	* mips.cc (Mips_scan_relocatable_relocs): Remove sh_type template
	parameter.
	(Mips_reloc_types): New class template.
	(Mips_classify_reloc): New class template.
	(Target_mips::Reltype): New typedef.
	(Target_mips::Relatype): New typedef.
	(Target_mips::emit_relocs_scan): New method.
	(Target_mips::get_r_sym): New method.
	(Target_mips::Relocatable_size_for_reloc): Replace with
	Mips_classify_reloc.
	(Target_mips::copy_reloc): Use Mips_classify_reloc.
	(Target_mips::gc_process_relocs): Likewise.
	(Target_mips::scan_relocs): Likewise.
	(Target_mips::relocate_section): Likewise.
	(Target_mips::scan_relocatable_relocs): Likewise.
	(Target_mips::relocate_relocs): Likewise.
	(mips_get_size_for_reloc): New function, factored out from
	Relocatable_size_for_reloc::get_size_for_reloc.
	(Target_mips::Scan::local): Use Mips_classify_reloc.
	(Target_mips::Scan::global): Likewise.
	(Target_mips::Relocate::relocate): Likewise.
	* powerpc.cc (Target_powerpc::emit_relocs_scan): New method.
	(Target_powerpc::Relocatable_size_for_reloc): Remove.
	(Target_powerpc::gc_process_relocs): Use Default_classify_reloc.
	(Target_powerpc::scan_relocs): Likewise.
	(Target_powerpc::relocate_section): Likewise.
	(Powerpc_scan_relocatable_reloc): Convert to class template.
	(Powerpc_scan_relocatable_reloc::Reltype): New typedef.
	(Powerpc_scan_relocatable_reloc::reloc_size): New const.
	(Powerpc_scan_relocatable_reloc::sh_type): New const.
	(Powerpc_scan_relocatable_reloc::get_r_sym): New method.
	(Powerpc_scan_relocatable_reloc::get_r_type): New method.
	(Target_powerpc::scan_relocatable_relocs): Use
	Powerpc_scan_relocatable_reloc.
	(Target_powerpc::relocate_relocs): Use Default_classify_reloc.
	* s390.cc (Target_s390::emit_relocs_scan): New method.
	(Target_s390::Relocatable_size_for_reloc): Remove.
	(Target_s390::gc_process_relocs): Use Default_classify_reloc.
	(Target_s390::scan_relocs): Likewise.
	(Target_s390::relocate_section): Likewise.
	(Target_s390::Relocatable_size_for_reloc::get_size_for_reloc):
	Remove.
	(Target_s390::scan_relocatable_relocs): Use Default_classify_reloc.
	(Target_s390::relocate_relocs): Use Default_classify_reloc.
	* sparc.cc (Target_sparc::emit_relocs_scan): New method.
	(Target_sparc::Relocatable_size_for_reloc): Remove.
	(Target_sparc::gc_process_relocs): Use Default_classify_reloc.
	(Target_sparc::scan_relocs): Likewise.
	(Target_sparc::relocate_section): Likewise.
	(Target_sparc::Relocatable_size_for_reloc::get_size_for_reloc):
	Remove.
	(Target_sparc::scan_relocatable_relocs): Use Default_classify_reloc.
	(Target_sparc::relocate_relocs): Use Default_classify_reloc.
	* tilegx.cc (Target_tilegx::emit_relocs_scan): New method.
	(Target_tilegx::Relocatable_size_for_reloc): Remove.
	(Target_tilegx::gc_process_relocs): Use Default_classify_reloc.
	(Target_tilegx::scan_relocs): Likewise.
	(Target_tilegx::relocate_section): Likewise.
	(Target_tilegx::Relocatable_size_for_reloc::get_size_for_reloc):
	Remove.
	(Target_tilegx::scan_relocatable_relocs): Use Default_classify_reloc.
	(Target_tilegx::relocate_relocs): Use Default_classify_reloc.
	* x86_64.cc (Target_x86_64::emit_relocs_scan): New method.
	(Target_x86_64::Relocatable_size_for_reloc): Remove.
	(Target_x86_64::gc_process_relocs): Use Default_classify_reloc.
	(Target_x86_64::scan_relocs): Likewise.
	(Target_x86_64::relocate_section): Likewise.
	(Target_x86_64::Relocatable_size_for_reloc::get_size_for_reloc):
	Remove.
	(Target_x86_64::scan_relocatable_relocs): Use Default_classify_reloc.
	(Target_x86_64::relocate_relocs): Use Default_classify_reloc.

	* testsuite/testfile.cc (Target_test::emit_relocs_scan): New method.

1 files changed, 74 insertions, 95 deletions

diff --git a/gold/x86_64.cc b/gold/x86_64.cc
index c48a513..3cfc064 100644
--- a/gold/x86_64.cc
+++ b/gold/x86_64.cc
@@ -496,6 +496,21 @@ class Target_x86_64 : public Sized_target<size, false>
 			  const unsigned char* plocal_symbols,
 			  Relocatable_relocs*);
 
+  // Scan the relocs for --emit-relocs.
+  void
+  emit_relocs_scan(Symbol_table* symtab,
+		   Layout* layout,
+		   Sized_relobj_file<size, false>* object,
+		   unsigned int data_shndx,
+		   unsigned int sh_type,
+		   const unsigned char* prelocs,
+		   size_t reloc_count,
+		   Output_section* output_section,
+		   bool needs_special_offset_handling,
+		   size_t local_symbol_count,
+		   const unsigned char* plocal_syms,
+		   Relocatable_relocs* rr);
+
   // Emit relocations for a section.
   void
   relocate_relocs(
@@ -859,15 +874,6 @@ class Target_x86_64 : public Sized_target<size, false>
     bool skip_call_tls_get_addr_;
   };
 
-  // A class which returns the size required for a relocation type,
-  // used while scanning relocs during a relocatable link.
-  class Relocatable_size_for_reloc
-  {
-   public:
-    unsigned int
-    get_size_for_reloc(unsigned int, Relobj*);
-  };
-
   // Check if relocation against this symbol is a candidate for
   // conversion from
   // mov foo@GOTPCREL(%rip), %reg
@@ -3191,15 +3197,16 @@ Target_x86_64<size>::gc_process_relocs(Symbol_table* symtab,
 				       size_t local_symbol_count,
 				       const unsigned char* plocal_symbols)
 {
+  typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, false>
+      Classify_reloc;
 
   if (sh_type == elfcpp::SHT_REL)
     {
       return;
     }
 
-   gold::gc_process_relocs<size, false, Target_x86_64<size>, elfcpp::SHT_RELA,
-			   typename Target_x86_64<size>::Scan,
-			   typename Target_x86_64<size>::Relocatable_size_for_reloc>(
+   gold::gc_process_relocs<size, false, Target_x86_64<size>, Scan,
+			   Classify_reloc>(
     symtab,
     layout,
     this,
@@ -3229,6 +3236,9 @@ Target_x86_64<size>::scan_relocs(Symbol_table* symtab,
 				 size_t local_symbol_count,
 				 const unsigned char* plocal_symbols)
 {
+  typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, false>
+      Classify_reloc;
+
   if (sh_type == elfcpp::SHT_REL)
     {
       gold_error(_("%s: unsupported REL reloc section"),
@@ -3236,8 +3246,7 @@ Target_x86_64<size>::scan_relocs(Symbol_table* symtab,
       return;
     }
 
-  gold::scan_relocs<size, false, Target_x86_64<size>, elfcpp::SHT_RELA,
-      typename Target_x86_64<size>::Scan>(
+  gold::scan_relocs<size, false, Target_x86_64<size>, Scan, Classify_reloc>(
     symtab,
     layout,
     this,
@@ -4268,11 +4277,13 @@ Target_x86_64<size>::relocate_section(
     section_size_type view_size,
     const Reloc_symbol_changes* reloc_symbol_changes)
 {
+  typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, false>
+      Classify_reloc;
+
   gold_assert(sh_type == elfcpp::SHT_RELA);
 
-  gold::relocate_section<size, false, Target_x86_64<size>, elfcpp::SHT_RELA,
-			 typename Target_x86_64<size>::Relocate,
-			 gold::Default_comdat_behavior>(
+  gold::relocate_section<size, false, Target_x86_64<size>, Relocate,
+			 gold::Default_comdat_behavior, Classify_reloc>(
     relinfo,
     this,
     prelocs,
@@ -4313,86 +4324,50 @@ Target_x86_64<size>::apply_relocation(
     view_size);
 }
 
-// Return the size of a relocation while scanning during a relocatable
-// link.
+// Scan the relocs during a relocatable link.
 
 template<int size>
-unsigned int
-Target_x86_64<size>::Relocatable_size_for_reloc::get_size_for_reloc(
-    unsigned int r_type,
-    Relobj* object)
+void
+Target_x86_64<size>::scan_relocatable_relocs(
+    Symbol_table* symtab,
+    Layout* layout,
+    Sized_relobj_file<size, false>* object,
+    unsigned int data_shndx,
+    unsigned int sh_type,
+    const unsigned char* prelocs,
+    size_t reloc_count,
+    Output_section* output_section,
+    bool needs_special_offset_handling,
+    size_t local_symbol_count,
+    const unsigned char* plocal_symbols,
+    Relocatable_relocs* rr)
 {
-  switch (r_type)
-    {
-    case elfcpp::R_X86_64_NONE:
-    case elfcpp::R_X86_64_GNU_VTINHERIT:
-    case elfcpp::R_X86_64_GNU_VTENTRY:
-    case elfcpp::R_X86_64_TLSGD:            // Global-dynamic
-    case elfcpp::R_X86_64_GOTPC32_TLSDESC:  // Global-dynamic (from ~oliva url)
-    case elfcpp::R_X86_64_TLSDESC_CALL:
-    case elfcpp::R_X86_64_TLSLD:            // Local-dynamic
-    case elfcpp::R_X86_64_DTPOFF32:
-    case elfcpp::R_X86_64_DTPOFF64:
-    case elfcpp::R_X86_64_GOTTPOFF:         // Initial-exec
-    case elfcpp::R_X86_64_TPOFF32:          // Local-exec
-      return 0;
+  typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, false>
+      Classify_reloc;
+  typedef gold::Default_scan_relocatable_relocs<Classify_reloc>
+      Scan_relocatable_relocs;
 
-    case elfcpp::R_X86_64_64:
-    case elfcpp::R_X86_64_PC64:
-    case elfcpp::R_X86_64_GOTOFF64:
-    case elfcpp::R_X86_64_GOTPC64:
-    case elfcpp::R_X86_64_PLTOFF64:
-    case elfcpp::R_X86_64_GOT64:
-    case elfcpp::R_X86_64_GOTPCREL64:
-    case elfcpp::R_X86_64_GOTPCREL:
-    case elfcpp::R_X86_64_GOTPCRELX:
-    case elfcpp::R_X86_64_REX_GOTPCRELX:
-    case elfcpp::R_X86_64_GOTPLT64:
-      return 8;
-
-    case elfcpp::R_X86_64_32:
-    case elfcpp::R_X86_64_32S:
-    case elfcpp::R_X86_64_PC32:
-    case elfcpp::R_X86_64_PC32_BND:
-    case elfcpp::R_X86_64_PLT32:
-    case elfcpp::R_X86_64_PLT32_BND:
-    case elfcpp::R_X86_64_GOTPC32:
-    case elfcpp::R_X86_64_GOT32:
-      return 4;
-
-    case elfcpp::R_X86_64_16:
-    case elfcpp::R_X86_64_PC16:
-      return 2;
-
-    case elfcpp::R_X86_64_8:
-    case elfcpp::R_X86_64_PC8:
-      return 1;
-
-    case elfcpp::R_X86_64_COPY:
-    case elfcpp::R_X86_64_GLOB_DAT:
-    case elfcpp::R_X86_64_JUMP_SLOT:
-    case elfcpp::R_X86_64_RELATIVE:
-    case elfcpp::R_X86_64_IRELATIVE:
-      // These are outstanding tls relocs, which are unexpected when linking
-    case elfcpp::R_X86_64_TPOFF64:
-    case elfcpp::R_X86_64_DTPMOD64:
-    case elfcpp::R_X86_64_TLSDESC:
-      object->error(_("unexpected reloc %u in object file"), r_type);
-      return 0;
+  gold_assert(sh_type == elfcpp::SHT_RELA);
 
-    case elfcpp::R_X86_64_SIZE32:
-    case elfcpp::R_X86_64_SIZE64:
-    default:
-      object->error(_("unsupported reloc %u against local symbol"), r_type);
-      return 0;
-    }
+  gold::scan_relocatable_relocs<size, false, Scan_relocatable_relocs>(
+    symtab,
+    layout,
+    object,
+    data_shndx,
+    prelocs,
+    reloc_count,
+    output_section,
+    needs_special_offset_handling,
+    local_symbol_count,
+    plocal_symbols,
+    rr);
 }
 
-// Scan the relocs during a relocatable link.
+// Scan the relocs for --emit-relocs.
 
 template<int size>
 void
-Target_x86_64<size>::scan_relocatable_relocs(
+Target_x86_64<size>::emit_relocs_scan(
     Symbol_table* symtab,
     Layout* layout,
     Sized_relobj_file<size, false>* object,
@@ -4403,16 +4378,17 @@ Target_x86_64<size>::scan_relocatable_relocs(
     Output_section* output_section,
     bool needs_special_offset_handling,
     size_t local_symbol_count,
-    const unsigned char* plocal_symbols,
+    const unsigned char* plocal_syms,
     Relocatable_relocs* rr)
 {
-  gold_assert(sh_type == elfcpp::SHT_RELA);
+  typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, false>
+      Classify_reloc;
+  typedef gold::Default_emit_relocs_strategy<Classify_reloc>
+      Emit_relocs_strategy;
 
-  typedef gold::Default_scan_relocatable_relocs<elfcpp::SHT_RELA,
-    Relocatable_size_for_reloc> Scan_relocatable_relocs;
+  gold_assert(sh_type == elfcpp::SHT_RELA);
 
-  gold::scan_relocatable_relocs<size, false, elfcpp::SHT_RELA,
-      Scan_relocatable_relocs>(
+  gold::scan_relocatable_relocs<size, false, Emit_relocs_strategy>(
     symtab,
     layout,
     object,
@@ -4422,7 +4398,7 @@ Target_x86_64<size>::scan_relocatable_relocs(
     output_section,
     needs_special_offset_handling,
     local_symbol_count,
-    plocal_symbols,
+    plocal_syms,
     rr);
 }
 
@@ -4443,9 +4419,12 @@ Target_x86_64<size>::relocate_relocs(
     unsigned char* reloc_view,
     section_size_type reloc_view_size)
 {
+  typedef gold::Default_classify_reloc<elfcpp::SHT_RELA, size, false>
+      Classify_reloc;
+
   gold_assert(sh_type == elfcpp::SHT_RELA);
 
-  gold::relocate_relocs<size, false, elfcpp::SHT_RELA>(
+  gold::relocate_relocs<size, false, Classify_reloc>(
     relinfo,
     prelocs,
     reloc_count,