Overhaul relocation framework to support overflow checking.

gold/
	PR gold/18695
	* reloc.h (Relocate_functions::Address): New typedef.
	(Relocate_functions::Addendtype): New typedef.
	(Relocate_functions::Overflow_check): New enum type.
	(Relocate_functions::Reloc_status): New enum type.
	(Relocate_functions::check_overflow): New function template.
	(Relocate_functions::rel): Add check parameter; check for overflow.
	(Relocate_functions::rel_unaligned): Likewise.
	(Relocate_functions::rela): Likewise.
	(Relocate_functions::pcrel): Likewise.
	(Relocate_functions::pcrel_unaligned): Likewise.
	(Relocate_functions::pcrela): Likewise.
	(Relocate_functions::rel8): Adjust parameter types.
	(Relocate_functions::rela8): Likewise.
	(Relocate_functions::pcrel8): Likewise.
	(Relocate_functions::pcrela8): Likewise.
	(Relocate_functions::rel16): Likewise.
	(Relocate_functions::rela168): Likewise.
	(Relocate_functions::pcrel16): Likewise.
	(Relocate_functions::pcrela16): Likewise.
	(Relocate_functions::rel32): Likewise.
	(Relocate_functions::rel32_unaligned): Likewise.
	(Relocate_functions::rela32): Likewise.
	(Relocate_functions::pcrel32): Likewise.
	(Relocate_functions::pcrel32_unaligned): Likewise.
	(Relocate_functions::pcrela32): Likewise.
	(Relocate_functions::rel8_check): New function.
	(Relocate_functions::rela8_check): New function.
	(Relocate_functions::pcrel8_check): New function.
	(Relocate_functions::pcrela8_check): New function.
	(Relocate_functions::rel16_check): New function.
	(Relocate_functions::rela168_check): New function.
	(Relocate_functions::pcrel16_check): New function.
	(Relocate_functions::pcrela16_check): New function.
	(Relocate_functions::rel32_check): New function.
	(Relocate_functions::rel32_unaligned_check): New function.
	(Relocate_functions::rela32_check): New function.
	(Relocate_functions::pcrel32_check): New function.
	(Relocate_functions::pcrel32_unaligned_check): New function.
	(Relocate_functions::pcrela32_check): New function.
	(Bits::has_unsigned_overflow32): New function.
	(Bits::has_unsigned_overflow): New function.
	* testsuite/Makefile.am (overflow_unittest): New test.
	* testsuite/Makefile.in: Regenerate.
	* testsuite/overflow_unittest.cc: New source file.

1 files changed, 413 insertions, 143 deletions

diff --git a/gold/reloc.h b/gold/reloc.h
index 5a72f27..4f1e753 100644
--- a/gold/reloc.h
+++ b/gold/reloc.h
@@ -321,406 +321,652 @@ class Relocatable_relocs
   Output_data* posd_;
 };
 
+template<int valsize>
+class Bits;
+
 // Standard relocation routines which are used on many targets.  Here
 // SIZE and BIG_ENDIAN refer to the target, not the relocation type.
 
 template<int size, bool big_endian>
 class Relocate_functions
 {
-private:
+ public:
+  typedef typename elfcpp::Elf_types<size>::Elf_Addr Address;
+  typedef typename elfcpp::Elf_types<size>::Elf_Swxword Addendtype;
+
+  enum Overflow_check
+  {
+    CHECK_NONE,
+    CHECK_SIGNED,
+    CHECK_UNSIGNED,
+    CHECK_SIGNED_OR_UNSIGNED
+  };
+
+  enum Reloc_status
+  {
+    RELOC_OK,
+    RELOC_OVERFLOW
+  };
+
+ private:
+  // Check for overflow.
+  template<int valsize>
+  static inline Reloc_status
+  check_overflow(Address value, Overflow_check check)
+  {
+    switch (check)
+      {
+      case CHECK_SIGNED:
+        if (size == 32)
+	  return (Bits<valsize>::has_overflow32(value)
+		  ? RELOC_OVERFLOW
+		  : RELOC_OK);
+	else
+	  return (Bits<valsize>::has_overflow(value)
+		  ? RELOC_OVERFLOW
+		  : RELOC_OK);
+      case CHECK_UNSIGNED:
+        if (size == 32)
+	  return (Bits<valsize>::has_unsigned_overflow32(value)
+		  ? RELOC_OVERFLOW
+		  : RELOC_OK);
+	else
+	  return (Bits<valsize>::has_unsigned_overflow(value)
+		  ? RELOC_OVERFLOW
+		  : RELOC_OK);
+      case CHECK_SIGNED_OR_UNSIGNED:
+        if (size == 32)
+	  return (Bits<valsize>::has_signed_unsigned_overflow32(value)
+		  ? RELOC_OVERFLOW
+		  : RELOC_OK);
+	else
+	  return (Bits<valsize>::has_signed_unsigned_overflow64(value)
+		  ? RELOC_OVERFLOW
+		  : RELOC_OK);
+      case CHECK_NONE:
+      default:
+        return RELOC_OK;
+      }
+  }
+
   // Do a simple relocation with the addend in the section contents.
   // VALSIZE is the size of the value.
   template<int valsize>
-  static inline void
-  rel(unsigned char* view,
-      typename elfcpp::Swap<valsize, big_endian>::Valtype value)
+  static inline Reloc_status
+  rel(unsigned char* view, Address value, Overflow_check check)
   {
     typedef typename elfcpp::Swap<valsize, big_endian>::Valtype Valtype;
     Valtype* wv = reinterpret_cast<Valtype*>(view);
-    Valtype x = elfcpp::Swap<valsize, big_endian>::readval(wv);
-    elfcpp::Swap<valsize, big_endian>::writeval(wv, x + value);
+    Valtype addend = elfcpp::Swap<valsize, big_endian>::readval(wv);
+    value += addend;
+    elfcpp::Swap<valsize, big_endian>::
+	writeval(wv, static_cast<Valtype>(value));
+    return check_overflow<valsize>(value, check);
   }
 
   // Like the above but for relocs at unaligned addresses.
   template<int valsize>
-  static inline void
-  rel_unaligned(unsigned char* view,
-	        typename elfcpp::Swap<valsize, big_endian>::Valtype value)
+  static inline Reloc_status
+  rel_unaligned(unsigned char* view, Address value, Overflow_check check)
   {
     typedef typename elfcpp::Swap_unaligned<valsize, big_endian>::Valtype
 	Valtype;
-    Valtype x = elfcpp::Swap_unaligned<valsize, big_endian>::readval(view);
-    elfcpp::Swap_unaligned<valsize, big_endian>::writeval(view, x + value);
+    Valtype addend = elfcpp::Swap_unaligned<valsize, big_endian>::readval(view);
+    value += addend;
+    elfcpp::Swap_unaligned<valsize, big_endian>::
+	writeval(view, static_cast<Valtype>(value));
+    return check_overflow<valsize>(value, check);
   }
 
   // Do a simple relocation using a Symbol_value with the addend in
   // the section contents.  VALSIZE is the size of the value to
   // relocate.
   template<int valsize>
-  static inline void
+  static inline Reloc_status
   rel(unsigned char* view,
       const Sized_relobj_file<size, big_endian>* object,
-      const Symbol_value<size>* psymval)
+      const Symbol_value<size>* psymval,
+      Overflow_check check)
   {
     typedef typename elfcpp::Swap<valsize, big_endian>::Valtype Valtype;
     Valtype* wv = reinterpret_cast<Valtype*>(view);
-    Valtype x = elfcpp::Swap<valsize, big_endian>::readval(wv);
-    x = psymval->value(object, x);
-    elfcpp::Swap<valsize, big_endian>::writeval(wv, x);
+    Valtype addend = elfcpp::Swap<valsize, big_endian>::readval(wv);
+    Address value = psymval->value(object, addend);
+    elfcpp::Swap<valsize, big_endian>::
+	writeval(wv, static_cast<Valtype>(value));
+    return check_overflow<valsize>(value, check);
   }
 
   // Like the above but for relocs at unaligned addresses.
   template<int valsize>
-  static inline void
+  static inline Reloc_status
   rel_unaligned(unsigned char* view,
                 const Sized_relobj_file<size, big_endian>* object,
-                const Symbol_value<size>* psymval)
+                const Symbol_value<size>* psymval,
+                Overflow_check check)
   {
     typedef typename elfcpp::Swap_unaligned<valsize, big_endian>::Valtype
         Valtype;
-    Valtype x = elfcpp::Swap_unaligned<valsize, big_endian>::readval(view);
-    x = psymval->value(object, x);
-    elfcpp::Swap_unaligned<valsize, big_endian>::writeval(view, x);
+    Valtype addend = elfcpp::Swap_unaligned<valsize, big_endian>::readval(view);
+    Address value = psymval->value(object, addend);
+    elfcpp::Swap_unaligned<valsize, big_endian>::writeval(view, value);
+    return check_overflow<valsize>(value, check);
   }
 
   // Do a simple relocation with the addend in the relocation.
   // VALSIZE is the size of the value.
   template<int valsize>
-  static inline void
-  rela(unsigned char* view,
-       typename elfcpp::Swap<valsize, big_endian>::Valtype value,
-       typename elfcpp::Swap<valsize, big_endian>::Valtype addend)
+  static inline Reloc_status
+  rela(unsigned char* view, Address value, Addendtype addend,
+       Overflow_check check)
   {
     typedef typename elfcpp::Swap<valsize, big_endian>::Valtype Valtype;
     Valtype* wv = reinterpret_cast<Valtype*>(view);
-    elfcpp::Swap<valsize, big_endian>::writeval(wv, value + addend);
+    value += addend;
+    elfcpp::Swap<valsize, big_endian>::writeval(wv, value);
+    return check_overflow<valsize>(value, check);
   }
 
   // Do a simple relocation using a symbol value with the addend in
   // the relocation.  VALSIZE is the size of the value.
   template<int valsize>
-  static inline void
+  static inline Reloc_status
   rela(unsigned char* view,
        const Sized_relobj_file<size, big_endian>* object,
        const Symbol_value<size>* psymval,
-       typename elfcpp::Swap<valsize, big_endian>::Valtype addend)
+       Addendtype addend,
+       Overflow_check check)
   {
     typedef typename elfcpp::Swap<valsize, big_endian>::Valtype Valtype;
     Valtype* wv = reinterpret_cast<Valtype*>(view);
-    Valtype x = psymval->value(object, addend);
-    elfcpp::Swap<valsize, big_endian>::writeval(wv, x);
+    Address value = psymval->value(object, addend);
+    elfcpp::Swap<valsize, big_endian>::writeval(wv, value);
+    return check_overflow<valsize>(value, check);
   }
 
   // Do a simple PC relative relocation with the addend in the section
   // contents.  VALSIZE is the size of the value.
   template<int valsize>
-  static inline void
-  pcrel(unsigned char* view,
-	typename elfcpp::Swap<valsize, big_endian>::Valtype value,
-	typename elfcpp::Elf_types<size>::Elf_Addr address)
+  static inline Reloc_status
+  pcrel(unsigned char* view, Address value, Address address,
+	Overflow_check check)
   {
     typedef typename elfcpp::Swap<valsize, big_endian>::Valtype Valtype;
     Valtype* wv = reinterpret_cast<Valtype*>(view);
-    Valtype x = elfcpp::Swap<valsize, big_endian>::readval(wv);
-    elfcpp::Swap<valsize, big_endian>::writeval(wv, x + value - address);
+    Valtype addend = elfcpp::Swap<valsize, big_endian>::readval(wv);
+    value = value + addend - address;
+    elfcpp::Swap<valsize, big_endian>::writeval(wv, value);
+    return check_overflow<valsize>(value, check);
   }
 
   // Like the above but for relocs at unaligned addresses.
   template<int valsize>
-  static inline void
-  pcrel_unaligned(unsigned char* view,
-		  typename elfcpp::Swap<valsize, big_endian>::Valtype value,
-		  typename elfcpp::Elf_types<size>::Elf_Addr address)
+  static inline Reloc_status
+  pcrel_unaligned(unsigned char* view, Address value, Address address,
+		  Overflow_check check)
   {
     typedef typename elfcpp::Swap<valsize, big_endian>::Valtype Valtype;
-    Valtype x = elfcpp::Swap_unaligned<valsize, big_endian>::readval(view);
-    elfcpp::Swap_unaligned<valsize, big_endian>::writeval(view,
-							  x + value - address);
+    Valtype addend = elfcpp::Swap_unaligned<valsize, big_endian>::readval(view);
+    value = value + addend - address;
+    elfcpp::Swap_unaligned<valsize, big_endian>::writeval(view, value);
+    return check_overflow<valsize>(value, check);
   }
 
   // Do a simple PC relative relocation with a Symbol_value with the
   // addend in the section contents.  VALSIZE is the size of the
   // value.
   template<int valsize>
-  static inline void
+  static inline Reloc_status
   pcrel(unsigned char* view,
 	const Sized_relobj_file<size, big_endian>* object,
 	const Symbol_value<size>* psymval,
-	typename elfcpp::Elf_types<size>::Elf_Addr address)
+	Address address,
+	Overflow_check check)
   {
     typedef typename elfcpp::Swap<valsize, big_endian>::Valtype Valtype;
     Valtype* wv = reinterpret_cast<Valtype*>(view);
-    Valtype x = elfcpp::Swap<valsize, big_endian>::readval(wv);
-    x = psymval->value(object, x);
-    elfcpp::Swap<valsize, big_endian>::writeval(wv, x - address);
+    Valtype addend = elfcpp::Swap<valsize, big_endian>::readval(wv);
+    Address value = psymval->value(object, addend) - address;
+    elfcpp::Swap<valsize, big_endian>::writeval(wv, value);
+    return check_overflow<valsize>(value, check);
   }
 
   // Do a simple PC relative relocation with the addend in the
   // relocation.  VALSIZE is the size of the value.
   template<int valsize>
-  static inline void
-  pcrela(unsigned char* view,
-	 typename elfcpp::Swap<valsize, big_endian>::Valtype value,
-	 typename elfcpp::Swap<valsize, big_endian>::Valtype addend,
-	 typename elfcpp::Elf_types<size>::Elf_Addr address)
+  static inline Reloc_status
+  pcrela(unsigned char* view, Address value, Addendtype addend, Address address,
+	 Overflow_check check)
   {
     typedef typename elfcpp::Swap<valsize, big_endian>::Valtype Valtype;
     Valtype* wv = reinterpret_cast<Valtype*>(view);
-    elfcpp::Swap<valsize, big_endian>::writeval(wv, value + addend - address);
+    value = value + addend - address;
+    elfcpp::Swap<valsize, big_endian>::writeval(wv, value);
+    return check_overflow<valsize>(value, check);
   }
 
   // Do a simple PC relative relocation with a Symbol_value with the
   // addend in the relocation.  VALSIZE is the size of the value.
   template<int valsize>
-  static inline void
+  static inline Reloc_status
   pcrela(unsigned char* view,
 	 const Sized_relobj_file<size, big_endian>* object,
 	 const Symbol_value<size>* psymval,
-	 typename elfcpp::Swap<valsize, big_endian>::Valtype addend,
-	 typename elfcpp::Elf_types<size>::Elf_Addr address)
+	 Addendtype addend,
+	 Address address,
+	 Overflow_check check)
   {
     typedef typename elfcpp::Swap<valsize, big_endian>::Valtype Valtype;
     Valtype* wv = reinterpret_cast<Valtype*>(view);
-    Valtype x = psymval->value(object, addend);
-    elfcpp::Swap<valsize, big_endian>::writeval(wv, x - address);
+    Address value = psymval->value(object, addend) - address;
+    elfcpp::Swap<valsize, big_endian>::writeval(wv, value);
+    return check_overflow<valsize>(value, check);
   }
 
   typedef Relocate_functions<size, big_endian> This;
 
-public:
+ public:
   // Do a simple 8-bit REL relocation with the addend in the section
   // contents.
   static inline void
-  rel8(unsigned char* view, unsigned char value)
-  { This::template rel<8>(view, value); }
+  rel8(unsigned char* view, Address value)
+  { This::template rel<8>(view, value, CHECK_NONE); }
+
+  static inline Reloc_status
+  rel8_check(unsigned char* view, Address value, Overflow_check check)
+  { return This::template rel<8>(view, value, check); }
 
   static inline void
   rel8(unsigned char* view,
        const Sized_relobj_file<size, big_endian>* object,
        const Symbol_value<size>* psymval)
-  { This::template rel<8>(view, object, psymval); }
+  { This::template rel<8>(view, object, psymval, CHECK_NONE); }
+
+  static inline Reloc_status
+  rel8_check(unsigned char* view,
+	     const Sized_relobj_file<size, big_endian>* object,
+	     const Symbol_value<size>* psymval,
+	     Overflow_check check)
+  { return This::template rel<8>(view, object, psymval, check); }
 
   // Do an 8-bit RELA relocation with the addend in the relocation.
   static inline void
-  rela8(unsigned char* view, unsigned char value, unsigned char addend)
-  { This::template rela<8>(view, value, addend); }
+  rela8(unsigned char* view, Address value, Addendtype addend)
+  { This::template rela<8>(view, value, addend, CHECK_NONE); }
+
+  static inline Reloc_status
+  rela8_check(unsigned char* view, Address value, Addendtype addend,
+	      Overflow_check check)
+  { return This::template rela<8>(view, value, addend, check); }
 
   static inline void
   rela8(unsigned char* view,
 	const Sized_relobj_file<size, big_endian>* object,
 	const Symbol_value<size>* psymval,
-	unsigned char addend)
-  { This::template rela<8>(view, object, psymval, addend); }
+	Addendtype addend)
+  { This::template rela<8>(view, object, psymval, addend, CHECK_NONE); }
+
+  static inline Reloc_status
+  rela8_check(unsigned char* view,
+	      const Sized_relobj_file<size, big_endian>* object,
+	      const Symbol_value<size>* psymval,
+	      Addendtype addend,
+	      Overflow_check check)
+  { return This::template rela<8>(view, object, psymval, addend, check); }
 
   // Do a simple 8-bit PC relative relocation with the addend in the
   // section contents.
   static inline void
-  pcrel8(unsigned char* view, unsigned char value,
-	 typename elfcpp::Elf_types<size>::Elf_Addr address)
-  { This::template pcrel<8>(view, value, address); }
+  pcrel8(unsigned char* view, unsigned char value, Address address)
+  { This::template pcrel<8>(view, value, address, CHECK_NONE); }
+
+  static inline Reloc_status
+  pcrel8_check(unsigned char* view, unsigned char value, Address address,
+	       Overflow_check check)
+  { return This::template pcrel<8>(view, value, address, check); }
 
   static inline void
   pcrel8(unsigned char* view,
 	 const Sized_relobj_file<size, big_endian>* object,
 	 const Symbol_value<size>* psymval,
-	 typename elfcpp::Elf_types<size>::Elf_Addr address)
-  { This::template pcrel<8>(view, object, psymval, address); }
+	 Address address)
+  { This::template pcrel<8>(view, object, psymval, address, CHECK_NONE); }
+
+  static inline Reloc_status
+  pcrel8_check(unsigned char* view,
+	       const Sized_relobj_file<size, big_endian>* object,
+	       const Symbol_value<size>* psymval,
+	       Address address,
+	       Overflow_check check)
+  { return This::template pcrel<8>(view, object, psymval, address, check); }
 
   // Do a simple 8-bit PC relative RELA relocation with the addend in
   // the reloc.
   static inline void
-  pcrela8(unsigned char* view, unsigned char value, unsigned char addend,
-	  typename elfcpp::Elf_types<size>::Elf_Addr address)
-  { This::template pcrela<8>(view, value, addend, address); }
+  pcrela8(unsigned char* view, Address value, Addendtype addend,
+	  Address address)
+  { This::template pcrela<8>(view, value, addend, address, CHECK_NONE); }
+
+  static inline Reloc_status
+  pcrela8_check(unsigned char* view, Address value, Addendtype addend,
+		Address address, Overflow_check check)
+  { return This::template pcrela<8>(view, value, addend, address, check); }
 
   static inline void
   pcrela8(unsigned char* view,
 	  const Sized_relobj_file<size, big_endian>* object,
 	  const Symbol_value<size>* psymval,
-	  unsigned char addend,
-	  typename elfcpp::Elf_types<size>::Elf_Addr address)
-  { This::template pcrela<8>(view, object, psymval, addend, address); }
+	  Addendtype addend,
+	  Address address)
+  { This::template pcrela<8>(view, object, psymval, addend, address,
+			     CHECK_NONE); }
+
+  static inline Reloc_status
+  pcrela8_check(unsigned char* view,
+		const Sized_relobj_file<size, big_endian>* object,
+		const Symbol_value<size>* psymval,
+		Addendtype addend,
+		Address address,
+		Overflow_check check)
+  { return This::template pcrela<8>(view, object, psymval, addend, address,
+				    check); }
 
   // Do a simple 16-bit REL relocation with the addend in the section
   // contents.
   static inline void
-  rel16(unsigned char* view, elfcpp::Elf_Half value)
-  { This::template rel<16>(view, value); }
+  rel16(unsigned char* view, Address value)
+  { This::template rel<16>(view, value, CHECK_NONE); }
+
+  static inline Reloc_status
+  rel16_check(unsigned char* view, Address value, Overflow_check check)
+  { return This::template rel<16>(view, value, check); }
 
   static inline void
   rel16(unsigned char* view,
 	const Sized_relobj_file<size, big_endian>* object,
 	const Symbol_value<size>* psymval)
-  { This::template rel<16>(view, object, psymval); }
+  { This::template rel<16>(view, object, psymval, CHECK_NONE); }
+
+  static inline Reloc_status
+  rel16_check(unsigned char* view,
+	      const Sized_relobj_file<size, big_endian>* object,
+	      const Symbol_value<size>* psymval,
+	      Overflow_check check)
+  { return This::template rel<16>(view, object, psymval, check); }
 
   // Do an 16-bit RELA relocation with the addend in the relocation.
   static inline void
-  rela16(unsigned char* view, elfcpp::Elf_Half value, elfcpp::Elf_Half addend)
-  { This::template rela<16>(view, value, addend); }
+  rela16(unsigned char* view, Address value, Addendtype addend)
+  { This::template rela<16>(view, value, addend, CHECK_NONE); }
+
+  static inline Reloc_status
+  rela16_check(unsigned char* view, Address value, Addendtype addend,
+	       Overflow_check check)
+  { return This::template rela<16>(view, value, addend, check); }
 
   static inline void
   rela16(unsigned char* view,
 	 const Sized_relobj_file<size, big_endian>* object,
 	 const Symbol_value<size>* psymval,
-	 elfcpp::Elf_Half addend)
-  { This::template rela<16>(view, object, psymval, addend); }
+	 Addendtype addend)
+  { This::template rela<16>(view, object, psymval, addend, CHECK_NONE); }
+
+  static inline Reloc_status
+  rela16_check(unsigned char* view,
+	       const Sized_relobj_file<size, big_endian>* object,
+	       const Symbol_value<size>* psymval,
+	       Addendtype addend,
+	       Overflow_check check)
+  { return This::template rela<16>(view, object, psymval, addend, check); }
 
   // Do a simple 16-bit PC relative REL relocation with the addend in
   // the section contents.
   static inline void
-  pcrel16(unsigned char* view, elfcpp::Elf_Half value,
-	  typename elfcpp::Elf_types<size>::Elf_Addr address)
-  { This::template pcrel<16>(view, value, address); }
+  pcrel16(unsigned char* view, Address value, Address address)
+  { This::template pcrel<16>(view, value, address, CHECK_NONE); }
+
+  static inline Reloc_status
+  pcrel16_check(unsigned char* view, Address value, Address address,
+		Overflow_check check)
+  { return This::template pcrel<16>(view, value, address, check); }
 
   static inline void
   pcrel16(unsigned char* view,
 	  const Sized_relobj_file<size, big_endian>* object,
 	  const Symbol_value<size>* psymval,
-	  typename elfcpp::Elf_types<size>::Elf_Addr address)
-  { This::template pcrel<16>(view, object, psymval, address); }
+	  Address address)
+  { This::template pcrel<16>(view, object, psymval, address, CHECK_NONE); }
+
+  static inline Reloc_status
+  pcrel16_check(unsigned char* view,
+		const Sized_relobj_file<size, big_endian>* object,
+		const Symbol_value<size>* psymval,
+		Address address,
+		Overflow_check check)
+  { return This::template pcrel<16>(view, object, psymval, address, check); }
 
   // Do a simple 16-bit PC relative RELA relocation with the addend in
   // the reloc.
   static inline void
-  pcrela16(unsigned char* view, elfcpp::Elf_Half value,
-	   elfcpp::Elf_Half addend,
-           typename elfcpp::Elf_types<size>::Elf_Addr address)
-  { This::template pcrela<16>(view, value, addend, address); }
+  pcrela16(unsigned char* view, Address value, Addendtype addend,
+	   Address address)
+  { This::template pcrela<16>(view, value, addend, address, CHECK_NONE); }
+
+  static inline Reloc_status
+  pcrela16_check(unsigned char* view, Address value, Addendtype addend,
+		 Address address, Overflow_check check)
+  { return This::template pcrela<16>(view, value, addend, address, check); }
 
   static inline void
   pcrela16(unsigned char* view,
 	   const Sized_relobj_file<size, big_endian>* object,
 	   const Symbol_value<size>* psymval,
-	   elfcpp::Elf_Half addend,
-	   typename elfcpp::Elf_types<size>::Elf_Addr address)
-  { This::template pcrela<16>(view, object, psymval, addend, address); }
+	   Addendtype addend,
+	   Address address)
+  { This::template pcrela<16>(view, object, psymval, addend, address,
+			      CHECK_NONE); }
+
+  static inline Reloc_status
+  pcrela16_check(unsigned char* view,
+		 const Sized_relobj_file<size, big_endian>* object,
+		 const Symbol_value<size>* psymval,
+		 Addendtype addend,
+		 Address address,
+		 Overflow_check check)
+  { return This::template pcrela<16>(view, object, psymval, addend, address,
+				     check); }
 
   // Do a simple 32-bit REL relocation with the addend in the section
   // contents.
   static inline void
-  rel32(unsigned char* view, elfcpp::Elf_Word value)
-  { This::template rel<32>(view, value); }
+  rel32(unsigned char* view, Address value)
+  { This::template rel<32>(view, value, CHECK_NONE); }
+
+  static inline Reloc_status
+  rel32_check(unsigned char* view, Address value, Overflow_check check)
+  { return This::template rel<32>(view, value, check); }
 
   // Like above but for relocs at unaligned addresses.
   static inline void
-  rel32_unaligned(unsigned char* view, elfcpp::Elf_Word value)
-  { This::template rel_unaligned<32>(view, value); }
+  rel32_unaligned(unsigned char* view, Address value)
+  { This::template rel_unaligned<32>(view, value, CHECK_NONE); }
+
+  static inline Reloc_status
+  rel32_unaligned_check(unsigned char* view, Address value,
+			Overflow_check check)
+  { return This::template rel_unaligned<32>(view, value, check); }
 
   static inline void
   rel32(unsigned char* view,
 	const Sized_relobj_file<size, big_endian>* object,
 	const Symbol_value<size>* psymval)
-  { This::template rel<32>(view, object, psymval); }
+  { This::template rel<32>(view, object, psymval, CHECK_NONE); }
+
+  static inline Reloc_status
+  rel32_check(unsigned char* view,
+	      const Sized_relobj_file<size, big_endian>* object,
+	      const Symbol_value<size>* psymval,
+	      Overflow_check check)
+  { return This::template rel<32>(view, object, psymval, check); }
 
   // Like above but for relocs at unaligned addresses.
   static inline void
   rel32_unaligned(unsigned char* view,
 	          const Sized_relobj_file<size, big_endian>* object,
 	          const Symbol_value<size>* psymval)
-  { This::template rel_unaligned<32>(view, object, psymval); }
+  { This::template rel_unaligned<32>(view, object, psymval, CHECK_NONE); }
 
-  // Do an 32-bit RELA relocation with the addend in the relocation.
+  static inline Reloc_status
+  rel32_unaligned_check(unsigned char* view,
+			const Sized_relobj_file<size, big_endian>* object,
+			const Symbol_value<size>* psymval,
+			Overflow_check check)
+  { return This::template rel_unaligned<32>(view, object, psymval, check); }
+
+  // Do a 32-bit RELA relocation with the addend in the relocation.
   static inline void
-  rela32(unsigned char* view, elfcpp::Elf_Word value, elfcpp::Elf_Word addend)
-  { This::template rela<32>(view, value, addend); }
+  rela32(unsigned char* view, Address value, Addendtype addend)
+  { This::template rela<32>(view, value, addend, CHECK_NONE); }
+
+  static inline Reloc_status
+  rela32(unsigned char* view, Address value, Addendtype addend,
+	 Overflow_check check)
+  { return This::template rela<32>(view, value, addend, check); }
 
   static inline void
   rela32(unsigned char* view,
 	 const Sized_relobj_file<size, big_endian>* object,
 	 const Symbol_value<size>* psymval,
-	 elfcpp::Elf_Word addend)
-  { This::template rela<32>(view, object, psymval, addend); }
+	 Addendtype addend)
+  { This::template rela<32>(view, object, psymval, addend, CHECK_NONE); }
+
+  static inline Reloc_status
+  rela32_check(unsigned char* view,
+	       const Sized_relobj_file<size, big_endian>* object,
+	       const Symbol_value<size>* psymval,
+	       Addendtype addend,
+	       Overflow_check check)
+  { return This::template rela<32>(view, object, psymval, addend, check); }
 
   // Do a simple 32-bit PC relative REL relocation with the addend in
   // the section contents.
   static inline void
-  pcrel32(unsigned char* view, elfcpp::Elf_Word value,
-	  typename elfcpp::Elf_types<size>::Elf_Addr address)
-  { This::template pcrel<32>(view, value, address); }
+  pcrel32(unsigned char* view, Address value, Address address)
+  { This::template pcrel<32>(view, value, address, CHECK_NONE); }
+
+  static inline Reloc_status
+  pcrel32_check(unsigned char* view, Address value, Address address,
+		Overflow_check check)
+  { return This::template pcrel<32>(view, value, address, check); }
 
   // Unaligned version of the above.
   static inline void
-  pcrel32_unaligned(unsigned char* view, elfcpp::Elf_Word value,
-		    typename elfcpp::Elf_types<size>::Elf_Addr address)
-  { This::template pcrel_unaligned<32>(view, value, address); }
+  pcrel32_unaligned(unsigned char* view, Address value, Address address)
+  { This::template pcrel_unaligned<32>(view, value, address, CHECK_NONE); }
+
+  static inline Reloc_status
+  pcrel32_unaligned_check(unsigned char* view, Address value, Address address,
+			  Overflow_check check)
+  { return This::template pcrel_unaligned<32>(view, value, address, check); }
 
   static inline void
   pcrel32(unsigned char* view,
 	  const Sized_relobj_file<size, big_endian>* object,
 	  const Symbol_value<size>* psymval,
-	  typename elfcpp::Elf_types<size>::Elf_Addr address)
-  { This::template pcrel<32>(view, object, psymval, address); }
+	  Address address)
+  { This::template pcrel<32>(view, object, psymval, address, CHECK_NONE); }
+
+  static inline Reloc_status
+  pcrel32_check(unsigned char* view,
+		const Sized_relobj_file<size, big_endian>* object,
+		const Symbol_value<size>* psymval,
+		Address address,
+		Overflow_check check)
+  { return This::template pcrel<32>(view, object, psymval, address, check); }
 
   // Do a simple 32-bit PC relative RELA relocation with the addend in
   // the relocation.
   static inline void
-  pcrela32(unsigned char* view, elfcpp::Elf_Word value,
-           elfcpp::Elf_Word addend,
-           typename elfcpp::Elf_types<size>::Elf_Addr address)
-  { This::template pcrela<32>(view, value, addend, address); }
+  pcrela32(unsigned char* view, Address value, Addendtype addend,
+           Address address)
+  { This::template pcrela<32>(view, value, addend, address, CHECK_NONE); }
+
+  static inline Reloc_status
+  pcrela32_check(unsigned char* view, Address value, Addendtype addend,
+           Address address, Overflow_check check)
+  { return This::template pcrela<32>(view, value, addend, address, check); }
 
   static inline void
   pcrela32(unsigned char* view,
 	   const Sized_relobj_file<size, big_endian>* object,
 	   const Symbol_value<size>* psymval,
-	   elfcpp::Elf_Word addend,
-	   typename elfcpp::Elf_types<size>::Elf_Addr address)
-  { This::template pcrela<32>(view, object, psymval, addend, address); }
+	   Addendtype addend,
+	   Address address)
+  { This::template pcrela<32>(view, object, psymval, addend, address,
+			      CHECK_NONE); }
+
+  static inline Reloc_status
+  pcrela32_check(unsigned char* view,
+	   const Sized_relobj_file<size, big_endian>* object,
+	   const Symbol_value<size>* psymval,
+	   Addendtype addend,
+	   Address address,
+	   Overflow_check check)
+  { return This::template pcrela<32>(view, object, psymval, addend, address,
+				     check); }
 
   // Do a simple 64-bit REL relocation with the addend in the section
   // contents.
   static inline void
-  rel64(unsigned char* view, elfcpp::Elf_Xword value)
-  { This::template rel<64>(view, value); }
+  rel64(unsigned char* view, Address value)
+  { This::template rel<64>(view, value, CHECK_NONE); }
 
   static inline void
   rel64(unsigned char* view,
 	const Sized_relobj_file<size, big_endian>* object,
 	const Symbol_value<size>* psymval)
-  { This::template rel<64>(view, object, psymval); }
+  { This::template rel<64>(view, object, psymval, CHECK_NONE); }
 
   // Do a 64-bit RELA relocation with the addend in the relocation.
   static inline void
-  rela64(unsigned char* view, elfcpp::Elf_Xword value,
-         elfcpp::Elf_Xword addend)
-  { This::template rela<64>(view, value, addend); }
+  rela64(unsigned char* view, Address value, Addendtype addend)
+  { This::template rela<64>(view, value, addend, CHECK_NONE); }
 
   static inline void
   rela64(unsigned char* view,
 	 const Sized_relobj_file<size, big_endian>* object,
 	 const Symbol_value<size>* psymval,
-	 elfcpp::Elf_Xword addend)
-  { This::template rela<64>(view, object, psymval, addend); }
+	 Addendtype addend)
+  { This::template rela<64>(view, object, psymval, addend, CHECK_NONE); }
 
   // Do a simple 64-bit PC relative REL relocation with the addend in
   // the section contents.
   static inline void
-  pcrel64(unsigned char* view, elfcpp::Elf_Xword value,
-	  typename elfcpp::Elf_types<size>::Elf_Addr address)
-  { This::template pcrel<64>(view, value, address); }
+  pcrel64(unsigned char* view, Address value, Address address)
+  { This::template pcrel<64>(view, value, address, CHECK_NONE); }
 
   static inline void
   pcrel64(unsigned char* view,
 	  const Sized_relobj_file<size, big_endian>* object,
 	  const Symbol_value<size>* psymval,
-	  typename elfcpp::Elf_types<size>::Elf_Addr address)
-  { This::template pcrel<64>(view, object, psymval, address); }
+	  Address address)
+  { This::template pcrel<64>(view, object, psymval, address, CHECK_NONE); }
 
   // Do a simple 64-bit PC relative RELA relocation with the addend in
   // the relocation.
   static inline void
-  pcrela64(unsigned char* view, elfcpp::Elf_Xword value,
-           elfcpp::Elf_Xword addend,
-           typename elfcpp::Elf_types<size>::Elf_Addr address)
-  { This::template pcrela<64>(view, value, addend, address); }
+  pcrela64(unsigned char* view, Address value, Addendtype addend,
+	   Address address)
+  { This::template pcrela<64>(view, value, addend, address, CHECK_NONE); }
 
   static inline void
   pcrela64(unsigned char* view,
 	   const Sized_relobj_file<size, big_endian>* object,
 	   const Symbol_value<size>* psymval,
-	   elfcpp::Elf_Xword addend,
-	   typename elfcpp::Elf_types<size>::Elf_Addr address)
-  { This::template pcrela<64>(view, object, psymval, addend, address); }
+	   Addendtype addend,
+	   Address address)
+  { This::template pcrela<64>(view, object, psymval, addend, address,
+			      CHECK_NONE); }
 };
 
 // Integer manipulation functions used by various targets when
@@ -761,6 +1007,18 @@ class Bits
     return as_signed > max || as_signed < min;
   }
 
+  // Return true if VAL (stored in a uint32_t) has overflowed an unsigned
+  // value with BITS bits.
+  static inline bool
+  has_unsigned_overflow32(uint32_t val)
+  {
+    gold_assert(bits > 0 && bits <= 32);
+    if (bits == 32)
+      return false;
+    int32_t max = static_cast<int32_t>((1U << bits) - 1);
+    return val > max;
+  }
+
   // Return true if VAL (stored in a uint32_t) has overflowed both a
   // signed and an unsigned value.  E.g.,
   // Bits<8>::has_signed_unsigned_overflow32 would check -128 <= VAL <
@@ -815,6 +1073,18 @@ class Bits
     return as_signed > max || as_signed < min;
   }
 
+  // Return true if VAL (stored in a uint64_t) has overflowed an unsigned
+  // value with BITS bits.
+  static inline bool
+  has_unsigned_overflow(uint64_t val)
+  {
+    gold_assert(bits > 0 && bits <= 64);
+    if (bits == 64)
+      return false;
+    int64_t max = static_cast<int64_t>((static_cast<uint64_t>(1) << bits) - 1);
+    return val > max;
+  }
+
   // Return true if VAL (stored in a uint64_t) has overflowed both a
   // signed and an unsigned value.  E.g.,
   // Bits<8>::has_signed_unsigned_overflow would check -128 <= VAL <