* tc-i386.h (i386_target_format): Define even for ELFs.

	(QWORD_MNEM_SUFFIX): New macro.
	(CpuK6,CpuAthlon,CpuSledgehammer, Cpu64, CpuNo64, CpuUnknownFlags):
	New macros
	(CpuMMX,CpuSSE,Cpu3dnow, CpuUnknown): Renumber.
	(IgnoreSize, DefaultSize, No_?Suf, FWait, IsString, regKludge, IsPrefix,
	ImmExt): Renumber.
	(Size64, No_qSuf, NoRex64, Rex64): New macros.
	(Reg64, Imm32S, Imm64, Disp32S, Disp64): New macros.
	(Imm8, Imm8S, Imm16, Imm32, Imm1, BaseIndex, Disp8, Disp16, Disp32,
	InOutPortReg,ShiftCount, Control, Debug, Test, FloatReg, FloatAcc,
	SReg2, SReg3, Acc, JumpAbsolute, RegMMX, RegXMM, EsSeg, InvMem): Renumber.
	(Reg, WordReg): Add Reg64.
	(Imm): Add Imm32S and Imm64.
	(EncImm): New.
	(Disp): Add Disp64 and Disp32S.
	(AnyMem): Add Disp32S.
	(RegRex, RegRex64): New macros.
	(rex_byte): New type.
	* tc-i386.c (set_16bit_code_flag): Kill.
	(fits_in_unsigned_long, fits_in_signed_long): New functions.
	(reloc): New parameter "signed"; support x86_64.
	(set_code_flag): New.
	(DEFAULT_ARCH): New macro; default to "i386".
	(default_arch): New static variable.
	(struct _i386_insn): New fields Operand_PCrel; rex.
	(flag_16bit_code): Kill; All tests replaced to "flag_code == CODE_64BIT";
	(flag_code): New enum and static variable.
	(use_rela_relocations): New static variable.
	(flag_code_names): New static variable.
	(cpu_arch_flags): Default to CpuUnknownFlags|CpuNo64.
	(cpu_arch): Add "sledgehammer"; Add CPUAthlon to Athlon and CpuK6 to
	K6 and Athlon.
	(i386_align_code): Return plain "nop" for x86_64.
	(mode_from_disp_size): Support Disp32S.
	(smallest_imm_type): Support Imm32S and Imm64.
	(offset_in_range): Support size of 8.
	(set_cpu_arch): Do not clobber to Cpu64/CpuNo64.
	(md_pseudo_table): Add "code64"; use set_code_flat.
	(md_begin): Emit sane error message on hash failure.
	(tc_i386_fix_adjustable): Support x86_64 relocations.
	(md_assemble): Support QWORD_MNEM_SUFFIX, REX registers,
	instructions supported on particular arch just partially,
	output of 64bit immediates, handling of Imm32S and Disp32S type.
	(i386_immedaite): Support x86_64 relocations; support 64bit constants.
	(i386_displacement): Likewise.
	(i386_index_check): Cleanup; support 64bit addresses.
	(md_apply_fix3): Support x86_64 relocation and rela.
	(md_longopts): Add "32" and "64".
	(md_parse_option): Add OPTION_32 and OPTION_64.
	(i386_target_format): Call even for ELFs; choose between
	elf64-x86-64 and elf32-i386.
	(i386_validate_fix): Refuse GOTOFF in 64bit mode.
	(tc_gen_reloc): Support rela relocations and x86_64.
	(intel_e09_1): Support QWORD.

	* i386.h (i386_optab): Replace "Imm" with "EncImm".
	(i386_regtab): Add flags field.

2 files changed, 876 insertions, 262 deletions

diff --git a/gas/config/tc-i386.c b/gas/config/tc-i386.c
index 8b0ab63..0485c67 100644
--- a/gas/config/tc-i386.c
+++ b/gas/config/tc-i386.c
@@ -21,6 +21,7 @@
 
 /* Intel 80386 machine specific gas.
    Written by Eliot Dresselhaus (eliot@mgm.mit.edu).
+   x86_64 support by Jan Hubicka (jh@suse.cz)
    Bugs & suggestions are completely welcome.  This is free software.
    Please help us make it better.  */
 
@@ -55,19 +56,26 @@ static int fits_in_signed_byte PARAMS ((offsetT));
 static int fits_in_unsigned_byte PARAMS ((offsetT));
 static int fits_in_unsigned_word PARAMS ((offsetT));
 static int fits_in_signed_word PARAMS ((offsetT));
+static int fits_in_unsigned_long PARAMS ((offsetT));
+static int fits_in_signed_long PARAMS ((offsetT));
 static int smallest_imm_type PARAMS ((offsetT));
 static offsetT offset_in_range PARAMS ((offsetT, int));
 static int add_prefix PARAMS ((unsigned int));
-static void set_16bit_code_flag PARAMS ((int));
+static void set_code_flag PARAMS ((int));
 static void set_16bit_gcc_code_flag PARAMS ((int));
 static void set_intel_syntax PARAMS ((int));
 static void set_cpu_arch PARAMS ((int));
 
 #ifdef BFD_ASSEMBLER
 static bfd_reloc_code_real_type reloc
-  PARAMS ((int, int, bfd_reloc_code_real_type));
+  PARAMS ((int, int, int, bfd_reloc_code_real_type));
 #endif
 
+#ifndef DEFAULT_ARCH
+#define DEFAULT_ARCH "i386"
+#endif
+static char *default_arch = DEFAULT_ARCH;
+
 /* 'md_assemble ()' gathers together information and puts it into a
    i386_insn.  */
 
@@ -103,6 +111,10 @@ struct _i386_insn
        operand.  */
     union i386_op op[MAX_OPERANDS];
 
+    /* Flags for operands.  */
+    unsigned int flags[MAX_OPERANDS];
+#define Operand_PCrel 1
+
     /* Relocation type for operand */
 #ifdef BFD_ASSEMBLER
     enum bfd_reloc_code_real disp_reloc[MAX_OPERANDS];
@@ -129,6 +141,7 @@ struct _i386_insn
        addressing modes of this insn are encoded.  */
 
     modrm_byte rm;
+    rex_byte rex;
     sib_byte sib;
   };
 
@@ -220,9 +233,24 @@ static expressionS disp_expressions[2], im_expressions[2];
 /* Current operand we are working on.  */
 static int this_operand;
 
-/* 1 if we're writing 16-bit code,
-   0 if 32-bit.  */
-static int flag_16bit_code;
+/* We support four different modes.  FLAG_CODE variable is used to distinguish
+   these.  */
+
+enum flag_code {
+	CODE_32BIT,
+	CODE_16BIT,
+	CODE_64BIT };
+
+static enum flag_code flag_code;
+static int use_rela_relocations = 0;
+
+/* The names used to print error messages.  */
+static const char *flag_code_names[] = 
+  {
+    "32",
+    "16",
+    "64"
+  };
 
 /* 1 for intel syntax,
    0 if att syntax.  */
@@ -243,7 +271,7 @@ static int quiet_warnings = 0;
 static const char *cpu_arch_name = NULL;
 
 /* CPU feature flags.  */
-static unsigned int cpu_arch_flags = 0;
+static unsigned int cpu_arch_flags = CpuUnknownFlags|CpuNo64;
 
 /* Interface to relax_segment.
    There are 2 relax states for 386 jump insns: one for conditional &
@@ -324,8 +352,9 @@ static const arch_entry cpu_arch[] = {
   {"i686",	Cpu086|Cpu186|Cpu286|Cpu386|Cpu486|Cpu586|Cpu686|CpuMMX|CpuSSE },
   {"pentium",	Cpu086|Cpu186|Cpu286|Cpu386|Cpu486|Cpu586|CpuMMX },
   {"pentiumpro",Cpu086|Cpu186|Cpu286|Cpu386|Cpu486|Cpu586|Cpu686|CpuMMX|CpuSSE },
-  {"k6",	Cpu086|Cpu186|Cpu286|Cpu386|Cpu486|Cpu586|CpuMMX|Cpu3dnow },
-  {"athlon",	Cpu086|Cpu186|Cpu286|Cpu386|Cpu486|Cpu586|Cpu686|CpuMMX|Cpu3dnow },
+  {"k6",	Cpu086|Cpu186|Cpu286|Cpu386|Cpu486|Cpu586|CpuK6|CpuMMX|Cpu3dnow },
+  {"athlon",	Cpu086|Cpu186|Cpu286|Cpu386|Cpu486|Cpu586|Cpu686|CpuK6|CpuAthlon|CpuMMX|Cpu3dnow },
+  {"sledgehammer",Cpu086|Cpu186|Cpu286|Cpu386|Cpu486|Cpu586|Cpu686|CpuK6|CpuAthlon|CpuSledgehammer|CpuMMX|Cpu3dnow|CpuSSE },
   {NULL, 0 }
 };
 
@@ -401,9 +430,14 @@ i386_align_code (fragP, count)
     f32_15, f32_15, f32_15, f32_15, f32_15, f32_15, f32_15
   };
 
+  /* ??? We can't use these fillers for x86_64, since they often kills the
+     upper halves.  Solve later.  */
+  if (flag_code == CODE_64BIT)
+    count = 1;
+
   if (count > 0 && count <= 15)
     {
-      if (flag_16bit_code)
+      if (flag_code == CODE_16BIT)
 	{
 	  memcpy (fragP->fr_literal + fragP->fr_fix,
 		  f16_patt[count - 1], count);
@@ -434,7 +468,7 @@ static INLINE unsigned int
 mode_from_disp_size (t)
      unsigned int t;
 {
-  return (t & Disp8) ? 1 : (t & (Disp16 | Disp32)) ? 2 : 0;
+  return (t & Disp8) ? 1 : (t & (Disp16 | Disp32 | Disp32S)) ? 2 : 0;
 }
 
 static INLINE int
@@ -464,13 +498,34 @@ fits_in_signed_word (num)
 {
   return (-32768 <= num) && (num <= 32767);
 }
+static INLINE int
+fits_in_signed_long (num)
+     offsetT num ATTRIBUTE_UNUSED;
+{
+#ifndef BFD64
+  return 1;
+#else
+  return (!(((offsetT) -1 << 31) & num)
+	  || (((offsetT) -1 << 31) & num) == ((offsetT) -1 << 31));
+#endif
+}				/* fits_in_signed_long() */
+static INLINE int
+fits_in_unsigned_long (num)
+     offsetT num ATTRIBUTE_UNUSED;
+{
+#ifndef BFD64
+  return 1;
+#else
+  return (num & (((offsetT) 2 << 31) - 1)) == num;
+#endif
+}				/* fits_in_unsigned_long() */
 
 static int
 smallest_imm_type (num)
      offsetT num;
 {
-  if (cpu_arch_flags != 0
-      && cpu_arch_flags != (Cpu086 | Cpu186 | Cpu286 | Cpu386 | Cpu486))
+  if (cpu_arch_flags != (Cpu086 | Cpu186 | Cpu286 | Cpu386 | Cpu486 | CpuNo64)
+      && !(cpu_arch_flags & (CpuUnknown)))
     {
       /* This code is disabled on the 486 because all the Imm1 forms
 	 in the opcode table are slower on the i486.  They're the
@@ -478,15 +533,19 @@ smallest_imm_type (num)
 	 displacement, which has another syntax if you really want to
 	 use that form.  */
       if (num == 1)
-	return Imm1 | Imm8 | Imm8S | Imm16 | Imm32;
+	return Imm1 | Imm8 | Imm8S | Imm16 | Imm32 | Imm32S | Imm64;
     }
   return (fits_in_signed_byte (num)
-	  ? (Imm8S | Imm8 | Imm16 | Imm32)
+	  ? (Imm8S | Imm8 | Imm16 | Imm32 | Imm32S | Imm64)
 	  : fits_in_unsigned_byte (num)
-	  ? (Imm8 | Imm16 | Imm32)
+	  ? (Imm8 | Imm16 | Imm32 | Imm32S | Imm64)
 	  : (fits_in_signed_word (num) || fits_in_unsigned_word (num))
-	  ? (Imm16 | Imm32)
-	  : (Imm32));
+	  ? (Imm16 | Imm32 | Imm32S | Imm64)
+	  : fits_in_signed_long (num)
+	  ? (Imm32 | Imm32S | Imm64)
+	  : fits_in_unsigned_long (num)
+	  ? (Imm32 | Imm64)
+	  : Imm64);
 }
 
 static offsetT
@@ -501,12 +560,16 @@ offset_in_range (val, size)
     case 1: mask = ((addressT) 1 <<  8) - 1; break;
     case 2: mask = ((addressT) 1 << 16) - 1; break;
     case 4: mask = ((addressT) 2 << 31) - 1; break;
+#ifdef BFD64
+    case 8: mask = ((addressT) 2 << 63) - 1; break;
+#endif
     default: abort ();
     }
 
   /* If BFD64, sign extend val.  */
-  if ((val & ~(((addressT) 2 << 31) - 1)) == 0)
-    val = (val ^ ((addressT) 1 << 31)) - ((addressT) 1 << 31);
+  if (!use_rela_relocations)
+    if ((val & ~(((addressT) 2 << 31) - 1)) == 0)
+      val = (val ^ ((addressT) 1 << 31)) - ((addressT) 1 << 31);
 
   if ((val & ~mask) != 0 && (val & ~mask) != ~mask)
     {
@@ -529,40 +592,43 @@ add_prefix (prefix)
   int ret = 1;
   int q;
 
-  switch (prefix)
-    {
-    default:
-      abort ();
+  if (prefix >= 0x40 && prefix < 0x50 && flag_code == CODE_64BIT)
+    q = REX_PREFIX;
+  else
+    switch (prefix)
+      {
+      default:
+	abort ();
 
-    case CS_PREFIX_OPCODE:
-    case DS_PREFIX_OPCODE:
-    case ES_PREFIX_OPCODE:
-    case FS_PREFIX_OPCODE:
-    case GS_PREFIX_OPCODE:
-    case SS_PREFIX_OPCODE:
-      q = SEG_PREFIX;
-      break;
+      case CS_PREFIX_OPCODE:
+      case DS_PREFIX_OPCODE:
+      case ES_PREFIX_OPCODE:
+      case FS_PREFIX_OPCODE:
+      case GS_PREFIX_OPCODE:
+      case SS_PREFIX_OPCODE:
+	q = SEG_PREFIX;
+	break;
 
-    case REPNE_PREFIX_OPCODE:
-    case REPE_PREFIX_OPCODE:
-      ret = 2;
-      /* fall thru */
-    case LOCK_PREFIX_OPCODE:
-      q = LOCKREP_PREFIX;
-      break;
+      case REPNE_PREFIX_OPCODE:
+      case REPE_PREFIX_OPCODE:
+	ret = 2;
+	/* fall thru */
+      case LOCK_PREFIX_OPCODE:
+	q = LOCKREP_PREFIX;
+	break;
 
-    case FWAIT_OPCODE:
-      q = WAIT_PREFIX;
-      break;
+      case FWAIT_OPCODE:
+	q = WAIT_PREFIX;
+	break;
 
-    case ADDR_PREFIX_OPCODE:
-      q = ADDR_PREFIX;
-      break;
+      case ADDR_PREFIX_OPCODE:
+	q = ADDR_PREFIX;
+	break;
 
-    case DATA_PREFIX_OPCODE:
-      q = DATA_PREFIX;
-      break;
-    }
+      case DATA_PREFIX_OPCODE:
+	q = DATA_PREFIX;
+	break;
+      }
 
   if (i.prefix[q])
     {
@@ -576,19 +642,31 @@ add_prefix (prefix)
 }
 
 static void
-set_16bit_code_flag (new_16bit_code_flag)
-     int new_16bit_code_flag;
+set_code_flag (value)
+     int  value;
 {
-  flag_16bit_code = new_16bit_code_flag;
+  flag_code = value;
+  cpu_arch_flags &= ~(Cpu64 | CpuNo64);
+  cpu_arch_flags |= (flag_code == CODE_64BIT ? Cpu64 : CpuNo64);
+  if (value == CODE_64BIT && !(cpu_arch_flags & CpuSledgehammer))
+    {
+      as_bad (_("64bit mode not supported on this CPU."));
+    }
+  if (value == CODE_32BIT && !(cpu_arch_flags & Cpu386))
+    {
+      as_bad (_("32bit mode not supported on this CPU."));
+    }
   stackop_size = '\0';
 }
 
 static void
-set_16bit_gcc_code_flag (new_16bit_code_flag)
-     int new_16bit_code_flag;
+set_16bit_gcc_code_flag (new_code_flag)
+     int new_code_flag;
 {
-  flag_16bit_code = new_16bit_code_flag;
-  stackop_size = new_16bit_code_flag ? 'l' : '\0';
+  flag_code = new_code_flag;
+  cpu_arch_flags &= ~(Cpu64 | CpuNo64);
+  cpu_arch_flags |= (flag_code == CODE_64BIT ? Cpu64 : CpuNo64);
+  stackop_size = 'l';
 }
 
 static void
@@ -647,7 +725,7 @@ set_cpu_arch (dummy)
 	  if (strcmp (string, cpu_arch[i].name) == 0)
 	    {
 	      cpu_arch_name = cpu_arch[i].name;
-	      cpu_arch_flags = cpu_arch[i].flags;
+	      cpu_arch_flags = cpu_arch[i].flags | (flag_code == CODE_64BIT ? Cpu64 : CpuNo64);
 	      break;
 	    }
 	}
@@ -679,9 +757,10 @@ const pseudo_typeS md_pseudo_table[] =
   {"value", cons, 2},
   {"noopt", s_ignore, 0},
   {"optim", s_ignore, 0},
-  {"code16gcc", set_16bit_gcc_code_flag, 1},
-  {"code16", set_16bit_code_flag, 1},
-  {"code32", set_16bit_code_flag, 0},
+  {"code16gcc", set_16bit_gcc_code_flag, CODE_16BIT},
+  {"code16", set_code_flag, CODE_16BIT},
+  {"code32", set_code_flag, CODE_32BIT},
+  {"code64", set_code_flag, CODE_64BIT},
   {"intel_syntax", set_intel_syntax, 1},
   {"att_syntax", set_intel_syntax, 0},
   {"file", dwarf2_directive_file, 0},
@@ -729,7 +808,6 @@ md_begin ()
 				    (PTR) core_optab);
 	    if (hash_err)
 	      {
-	      hash_error:
 		as_fatal (_("Internal Error:  Can't hash %s: %s"),
 			  (optab - 1)->name,
 			  hash_err);
@@ -753,7 +831,9 @@ md_begin ()
       {
 	hash_err = hash_insert (reg_hash, regtab->reg_name, (PTR) regtab);
 	if (hash_err)
-	  goto hash_error;
+	  as_fatal (_("Internal Error:  Can't hash %s: %s"),
+		    regtab->reg_name,
+		    hash_err);
       }
   }
 
@@ -987,13 +1067,12 @@ tc_i386_force_relocation (fixp)
 }
 
 #ifdef BFD_ASSEMBLER
-static bfd_reloc_code_real_type reloc
-  PARAMS ((int, int, bfd_reloc_code_real_type));
 
 static bfd_reloc_code_real_type
-reloc (size, pcrel, other)
+reloc (size, pcrel, sign, other)
      int size;
      int pcrel;
+     int sign;
      bfd_reloc_code_real_type other;
 {
   if (other != NO_RELOC)
@@ -1001,6 +1080,8 @@ reloc (size, pcrel, other)
 
   if (pcrel)
     {
+      if (!sign)
+	as_bad(_("There are no unsigned pc-relative relocations"));
       switch (size)
 	{
 	case 1: return BFD_RELOC_8_PCREL;
@@ -1011,15 +1092,24 @@ reloc (size, pcrel, other)
     }
   else
     {
-      switch (size)
-	{
-	case 1: return BFD_RELOC_8;
-	case 2: return BFD_RELOC_16;
-	case 4: return BFD_RELOC_32;
-	}
-      as_bad (_("can not do %d byte relocation"), size);
+      if (sign)
+        switch (size)
+	  {
+	  case 4: return BFD_RELOC_X86_64_32S;
+	  }
+      else
+	switch (size)
+	  {
+	  case 1: return BFD_RELOC_8;
+	  case 2: return BFD_RELOC_16;
+	  case 4: return BFD_RELOC_32;
+	  case 8: return BFD_RELOC_64;
+	  }
+      as_bad (_("can not do %s %d byte relocation"),
+	      sign ? "signed" : "unsigned", size);
     }
 
+  abort();
   return BFD_RELOC_NONE;
 }
 
@@ -1043,6 +1133,8 @@ tc_i386_fix_adjustable (fixP)
   if (fixP->fx_r_type == BFD_RELOC_386_GOTOFF
       || fixP->fx_r_type == BFD_RELOC_386_PLT32
       || fixP->fx_r_type == BFD_RELOC_386_GOT32
+      || fixP->fx_r_type == BFD_RELOC_X86_64_PLT32
+      || fixP->fx_r_type == BFD_RELOC_X86_64_GOT32
       || fixP->fx_r_type == BFD_RELOC_VTABLE_INHERIT
       || fixP->fx_r_type == BFD_RELOC_VTABLE_ENTRY)
     return 0;
@@ -1057,6 +1149,8 @@ tc_i386_fix_adjustable (fixP)
 #define BFD_RELOC_386_PLT32	0
 #define BFD_RELOC_386_GOT32	0
 #define BFD_RELOC_386_GOTOFF	0
+#define BFD_RELOC_X86_64_PLT32	0
+#define BFD_RELOC_X86_64_GOT32	0
 #endif
 
 static int intel_float_operand PARAMS ((char *mnemonic));
@@ -1153,7 +1247,7 @@ md_assemble (line)
 	       Similarly, in 32-bit mode, do not allow addr32 or data32.  */
 	    if ((current_templates->start->opcode_modifier & (Size16 | Size32))
 		&& (((current_templates->start->opcode_modifier & Size32) != 0)
-		    ^ flag_16bit_code))
+		    ^ (flag_code == CODE_16BIT)))
 	      {
 		as_bad (_("redundant %s prefix"),
 			current_templates->start->name);
@@ -1182,6 +1276,7 @@ md_assemble (line)
 	  {
 	  case WORD_MNEM_SUFFIX:
 	  case BYTE_MNEM_SUFFIX:
+	  case QWORD_MNEM_SUFFIX:
 	    i.suffix = mnem_p[-1];
 	    mnem_p[-1] = '\0';
 	    current_templates = hash_find (op_hash, mnemonic);
@@ -1219,12 +1314,13 @@ md_assemble (line)
     /* Check if instruction is supported on specified architecture.  */
     if (cpu_arch_flags != 0)
       {
-	if (current_templates->start->cpu_flags & ~cpu_arch_flags)
+	if ((current_templates->start->cpu_flags & ~(Cpu64 | CpuNo64))
+	    & ~(cpu_arch_flags & ~(Cpu64 | CpuNo64)))
 	  {
 	    as_warn (_("`%s' is not supported on `%s'"),
 		     current_templates->start->name, cpu_arch_name);
 	  }
-	else if ((Cpu386 & ~cpu_arch_flags) && !flag_16bit_code)
+	else if ((Cpu386 & ~cpu_arch_flags) && (flag_code != CODE_16BIT))
 	  {
 	    as_warn (_("use .code16 to ensure correct addressing mode"));
 	  }
@@ -1394,9 +1490,9 @@ md_assemble (line)
 	union i386_op temp_op;
 	unsigned int temp_type;
 #ifdef BFD_ASSEMBLER
-	enum bfd_reloc_code_real temp_disp_reloc;
+	enum bfd_reloc_code_real temp_reloc;
 #else
-	int temp_disp_reloc;
+	int temp_reloc;
 #endif
 	int xchg1 = 0;
 	int xchg2 = 0;
@@ -1417,9 +1513,9 @@ md_assemble (line)
 	temp_op = i.op[xchg2];
 	i.op[xchg2] = i.op[xchg1];
 	i.op[xchg1] = temp_op;
-	temp_disp_reloc = i.disp_reloc[xchg2];
+	temp_reloc = i.disp_reloc[xchg2];
 	i.disp_reloc[xchg2] = i.disp_reloc[xchg1];
-	i.disp_reloc[xchg1] = temp_disp_reloc;
+	i.disp_reloc[xchg1] = temp_reloc;
 
 	if (i.mem_operands == 2)
 	  {
@@ -1452,38 +1548,82 @@ md_assemble (line)
 		    guess_suffix = BYTE_MNEM_SUFFIX;
 		  else if (i.types[op] & Reg16)
 		    guess_suffix = WORD_MNEM_SUFFIX;
+		  else if (i.types[op] & Reg32)
+		    guess_suffix = LONG_MNEM_SUFFIX;
+		  else if (i.types[op] & Reg64)
+		    guess_suffix = QWORD_MNEM_SUFFIX;
 		  break;
 		}
 	  }
-	else if (flag_16bit_code ^ (i.prefix[DATA_PREFIX] != 0))
+	else if ((flag_code == CODE_16BIT) ^ (i.prefix[DATA_PREFIX] != 0))
 	  guess_suffix = WORD_MNEM_SUFFIX;
 
 	for (op = i.operands; --op >= 0;)
-	  if ((i.types[op] & Imm)
-	      && i.op[op].imms->X_op == O_constant)
+	  if (i.types[op] & Imm)
 	    {
-	      /* If a suffix is given, this operand may be shortened.  */
-	      switch (guess_suffix)
-		{
-		case WORD_MNEM_SUFFIX:
-		  i.types[op] |= Imm16;
-		  break;
-		case BYTE_MNEM_SUFFIX:
-		  i.types[op] |= Imm16 | Imm8 | Imm8S;
-		  break;
-		}
+	      switch (i.op[op].imms->X_op)
+	        {
+		  case O_constant:
+		    /* If a suffix is given, this operand may be shortened.  */
+		    switch (guess_suffix)
+		      {
+		      case LONG_MNEM_SUFFIX:
+			i.types[op] |= Imm32 | Imm64;
+			break;
+		      case WORD_MNEM_SUFFIX:
+			i.types[op] |= Imm16 | Imm32S | Imm32 | Imm64;
+			break;
+		      case BYTE_MNEM_SUFFIX:
+			i.types[op] |= Imm16 | Imm8 | Imm8S | Imm32S | Imm32 | Imm64;
+			break;
+		      }
 
-	      /* If this operand is at most 16 bits, convert it to a
-		 signed 16 bit number before trying to see whether it will
-		 fit in an even smaller size.  This allows a 16-bit operand
-		 such as $0xffe0 to be recognised as within Imm8S range.  */
-	      if ((i.types[op] & Imm16)
-		  && (i.op[op].imms->X_add_number & ~(offsetT)0xffff) == 0)
-		{
-		  i.op[op].imms->X_add_number =
-		    (((i.op[op].imms->X_add_number & 0xffff) ^ 0x8000) - 0x8000);
+		    /* If this operand is at most 16 bits, convert it to a
+		       signed 16 bit number before trying to see whether it will
+		       fit in an even smaller size.  This allows a 16-bit operand
+		       such as $0xffe0 to be recognised as within Imm8S range.  */
+		    if ((i.types[op] & Imm16)
+			&& (i.op[op].imms->X_add_number & ~(offsetT)0xffff) == 0)
+		      {
+			i.op[op].imms->X_add_number =
+			  (((i.op[op].imms->X_add_number & 0xffff) ^ 0x8000) - 0x8000);
+		      }
+		    if ((i.types[op] & Imm32)
+			&& (i.op[op].imms->X_add_number & ~(((offsetT) 2 << 31) - 1)) == 0)
+		      {
+			i.op[op].imms->X_add_number =
+			  (i.op[op].imms->X_add_number ^ ((offsetT) 1 << 31)) - ((addressT) 1 << 31);
+		      }
+		    i.types[op] |= smallest_imm_type (i.op[op].imms->X_add_number);
+		    /* We must avoid matching of Imm32 templates when 64bit only immediate is available.  */
+		    if (guess_suffix == QWORD_MNEM_SUFFIX)
+		      i.types[op] &= ~Imm32;
+		    break;
+		  case O_absent:
+		  case O_register:
+		    abort();
+		  /* Symbols and expressions.  */
+		  default:
+		    /* Convert symbolic operand to proper sizes for matching.  */
+		    switch (guess_suffix)
+		      {
+		        case QWORD_MNEM_SUFFIX:
+			  i.types[op] = Imm64 | Imm32S;
+			  break;
+		        case LONG_MNEM_SUFFIX:
+			  i.types[op] = Imm32 | Imm64;
+			  break;
+		        case WORD_MNEM_SUFFIX:
+			  i.types[op] = Imm16 | Imm32 | Imm64;
+			  break;
+			  break;
+		        case BYTE_MNEM_SUFFIX:
+			  i.types[op] = Imm8 | Imm8S | Imm16 | Imm32S | Imm32;
+				break;
+			  break;
+		      }
+		    break;
 		}
-	      i.types[op] |= smallest_imm_type ((long) i.op[op].imms->X_add_number);
 	    }
       }
 
@@ -1507,7 +1647,23 @@ md_assemble (line)
 
 		  disp = (((disp & 0xffff) ^ 0x8000) - 0x8000);
 		}
-	      if (fits_in_signed_byte (disp))
+	      else if (i.types[op] & Disp32)
+		{
+		  /* We know this operand is at most 32 bits, so convert to a
+		     signed 32 bit number before trying to see whether it will
+		     fit in an even smaller size.  */
+		  disp &= (((offsetT) 2 << 31) - 1);
+		  disp = (disp ^ ((offsetT) 1 << 31)) - ((addressT) 1 << 31);
+		}
+	      if (flag_code == CODE_64BIT)
+		{
+		  if (fits_in_signed_long (disp))
+		    i.types[op] |= Disp32S;
+		  if (fits_in_unsigned_long (disp))
+		    i.types[op] |= Disp32;
+		}
+	      if ((i.types[op] & (Disp32 | Disp32S | Disp16))
+		  && fits_in_signed_byte (disp))
 		i.types[op] |= Disp8;
 	    }
       }
@@ -1524,7 +1680,9 @@ md_assemble (line)
 			  ? No_sSuf
 			  : (i.suffix == LONG_MNEM_SUFFIX
 			     ? No_lSuf
-			     : (i.suffix == LONG_DOUBLE_MNEM_SUFFIX ? No_xSuf : 0)))));
+			     : (i.suffix == QWORD_MNEM_SUFFIX
+				? No_qSuf
+				: (i.suffix == LONG_DOUBLE_MNEM_SUFFIX ? No_xSuf : 0))))));
 
     for (t = current_templates->start;
 	 t < current_templates->end;
@@ -1585,10 +1743,9 @@ md_assemble (line)
 		/* found_reverse_match holds which of D or FloatDR
 		   we've found.  */
 		found_reverse_match = t->opcode_modifier & (D|FloatDR);
-		break;
 	      }
 	    /* Found a forward 2 operand match here.  */
-	    if (t->operands == 3)
+	    else if (t->operands == 3)
 	      {
 		/* Here we make use of the fact that there are no
 		   reverse match 3 operand instructions, and all 3
@@ -1606,6 +1763,11 @@ md_assemble (line)
 	    /* Found either forward/reverse 2 or 3 operand match here:
 	       slip through to break.  */
 	  }
+	if (t->cpu_flags & ~cpu_arch_flags)
+	  {
+	    found_reverse_match = 0;
+	    continue;
+	  }
 	/* We've found a match; break out of loop.  */
 	break;
       }
@@ -1690,12 +1852,24 @@ md_assemble (line)
 	  }
       }
 
+    if (i.reg_operands && flag_code < CODE_64BIT)
+      {
+	int op;
+	for (op = i.operands; --op >= 0; )
+	  if ((i.types[op] & Reg)
+	      && (i.op[op].regs->reg_flags & (RegRex64|RegRex)))
+	    as_bad (_("Extended register `%%%s' available only in 64bit mode."),
+		    i.op[op].regs->reg_name);
+      }
+
     /* If matched instruction specifies an explicit instruction mnemonic
        suffix, use it.  */
-    if (i.tm.opcode_modifier & (Size16 | Size32))
+    if (i.tm.opcode_modifier & (Size16 | Size32 | Size64))
       {
 	if (i.tm.opcode_modifier & Size16)
 	  i.suffix = WORD_MNEM_SUFFIX;
+	else if (i.tm.opcode_modifier & Size64)
+	  i.suffix = QWORD_MNEM_SUFFIX;
 	else
 	  i.suffix = LONG_MNEM_SUFFIX;
       }
@@ -1715,6 +1889,7 @@ md_assemble (line)
 		{
 		  i.suffix = ((i.types[op] & Reg8) ? BYTE_MNEM_SUFFIX :
 			      (i.types[op] & Reg16) ? WORD_MNEM_SUFFIX :
+			      (i.types[op] & Reg64) ? QWORD_MNEM_SUFFIX :
 			      LONG_MNEM_SUFFIX);
 		  break;
 		}
@@ -1734,6 +1909,7 @@ md_assemble (line)
 		if (intel_syntax
 		    && (i.tm.base_opcode == 0xfb7
 			|| i.tm.base_opcode == 0xfb6
+			|| i.tm.base_opcode == 0x63
 			|| i.tm.base_opcode == 0xfbe
 			|| i.tm.base_opcode == 0xfbf))
 		  continue;
@@ -1747,6 +1923,13 @@ md_assemble (line)
 #endif
 		    )
 		  {
+		    /* Prohibit these changes in the 64bit mode, since
+		       the lowering is more complicated.  */
+		    if (flag_code == CODE_64BIT
+			&& (i.tm.operand_types[op] & InOutPortReg) == 0)
+		      as_bad (_("Incorrect register `%%%s' used with`%c' suffix"),
+			      i.op[op].regs->reg_name,
+			      i.suffix);
 #if REGISTER_WARNINGS
 		    if (!quiet_warnings
 			&& (i.tm.operand_types[op] & InOutPortReg) == 0)
@@ -1787,18 +1970,63 @@ md_assemble (line)
 			  i.suffix);
 		  return;
 		}
-#if REGISTER_WARNINGS
 	      /* Warn if the e prefix on a general reg is missing.  */
-	      else if (!quiet_warnings
+	      else if ((!quiet_warnings || flag_code == CODE_64BIT)
 		       && (i.types[op] & Reg16) != 0
 		       && (i.tm.operand_types[op] & (Reg32|Acc)) != 0)
 		{
-		  as_warn (_("using `%%%s' instead of `%%%s' due to `%c' suffix"),
-			   (i.op[op].regs + 8)->reg_name,
-			   i.op[op].regs->reg_name,
-			   i.suffix);
-		}
+		  /* Prohibit these changes in the 64bit mode, since
+		     the lowering is more complicated.  */
+		  if (flag_code == CODE_64BIT)
+		    as_bad (_("Incorrect register `%%%s' used with`%c' suffix"),
+			    i.op[op].regs->reg_name,
+			    i.suffix);
+#if REGISTER_WARNINGS
+		  else
+		    as_warn (_("using `%%%s' instead of `%%%s' due to `%c' suffix"),
+			     (i.op[op].regs + 8)->reg_name,
+			     i.op[op].regs->reg_name,
+			     i.suffix);
 #endif
+		}
+	      /* Warn if the r prefix on a general reg is missing.  */
+	      else if ((i.types[op] & Reg64) != 0
+		       && (i.tm.operand_types[op] & (Reg32|Acc)) != 0)
+		{
+		  as_bad (_("Incorrect register `%%%s' used with`%c' suffix"),
+			  i.op[op].regs->reg_name,
+			  i.suffix);
+		}
+	  }
+	else if (i.suffix == QWORD_MNEM_SUFFIX)
+	  {
+	    int op;
+	    if (flag_code < CODE_64BIT)
+	      as_bad (_("64bit operations available only in 64bit modes."));
+
+	    for (op = i.operands; --op >= 0; )
+	      /* Reject eight bit registers, except where the template
+		 requires them. (eg. movzb)  */
+	      if ((i.types[op] & Reg8) != 0
+		  && (i.tm.operand_types[op] & (Reg16|Reg32|Acc)) != 0)
+		{
+		  as_bad (_("`%%%s' not allowed with `%s%c'"),
+			  i.op[op].regs->reg_name,
+			  i.tm.name,
+			  i.suffix);
+		  return;
+		}
+	      /* Warn if the e prefix on a general reg is missing.  */
+	      else if (((i.types[op] & Reg16) != 0
+		        || (i.types[op] & Reg32) != 0)
+		       && (i.tm.operand_types[op] & (Reg32|Acc)) != 0)
+		{
+		  /* Prohibit these changes in the 64bit mode, since
+		     the lowering is more complicated.  */
+		  as_bad (_("Incorrect register `%%%s' used with`%c' suffix"),
+			  i.op[op].regs->reg_name,
+			  i.suffix);
+		}
 	  }
 	else if (i.suffix == WORD_MNEM_SUFFIX)
 	  {
@@ -1815,18 +2043,25 @@ md_assemble (line)
 			  i.suffix);
 		  return;
 		}
-#if REGISTER_WARNINGS
 	      /* Warn if the e prefix on a general reg is present.  */
-	      else if (!quiet_warnings
+	      else if ((!quiet_warnings || flag_code == CODE_64BIT)
 		       && (i.types[op] & Reg32) != 0
 		       && (i.tm.operand_types[op] & (Reg16|Acc)) != 0)
 		{
-		  as_warn (_("using `%%%s' instead of `%%%s' due to `%c' suffix"),
-			   (i.op[op].regs - 8)->reg_name,
-			   i.op[op].regs->reg_name,
-			   i.suffix);
-		}
+		  /* Prohibit these changes in the 64bit mode, since
+		     the lowering is more complicated.  */
+		  if (flag_code == CODE_64BIT)
+		    as_bad (_("Incorrect register `%%%s' used with`%c' suffix"),
+			    i.op[op].regs->reg_name,
+			    i.suffix);
+		  else
+#if REGISTER_WARNINGS
+		    as_warn (_("using `%%%s' instead of `%%%s' due to `%c' suffix"),
+			     (i.op[op].regs - 8)->reg_name,
+			     i.op[op].regs->reg_name,
+			     i.suffix);
 #endif
+		}
 	  }
 	else if (intel_syntax && (i.tm.opcode_modifier & IgnoreSize))
 	  /* Do nothing if the instruction is going to ignore the prefix.  */
@@ -1838,46 +2073,57 @@ md_assemble (line)
       {
 	i.suffix = stackop_size;
       }
-
     /* Make still unresolved immediate matches conform to size of immediate
        given in i.suffix.  Note: overlap2 cannot be an immediate!  */
-    if ((overlap0 & (Imm8 | Imm8S | Imm16 | Imm32))
+    if ((overlap0 & (Imm8 | Imm8S | Imm16 | Imm32 | Imm32S))
 	&& overlap0 != Imm8 && overlap0 != Imm8S
-	&& overlap0 != Imm16 && overlap0 != Imm32)
+        && overlap0 != Imm16 && overlap0 != Imm32S
+ 	&& overlap0 != Imm32 && overlap0 != Imm64)
       {
 	if (i.suffix)
 	  {
 	    overlap0 &= (i.suffix == BYTE_MNEM_SUFFIX ? (Imm8 | Imm8S) :
-			 (i.suffix == WORD_MNEM_SUFFIX ? Imm16 : Imm32));
+			(i.suffix == WORD_MNEM_SUFFIX ? Imm16 : 
+			(i.suffix == QWORD_MNEM_SUFFIX ? Imm64 | Imm32S : Imm32)));
 	  }
-	else if (overlap0 == (Imm16 | Imm32))
+	else if (overlap0 == (Imm16 | Imm32S | Imm32)
+		 || overlap0 == (Imm16 | Imm32)
+		 || overlap0 == (Imm16 | Imm32S))
 	  {
 	    overlap0 =
-	      (flag_16bit_code ^ (i.prefix[DATA_PREFIX] != 0)) ? Imm16 : Imm32;
+	      ((flag_code == CODE_16BIT) ^ (i.prefix[DATA_PREFIX] != 0)) ? Imm16 : Imm32S;
 	  }
-	else
+	if (overlap0 != Imm8 && overlap0 != Imm8S
+	    && overlap0 != Imm16 && overlap0 != Imm32S
+	    && overlap0 != Imm32 && overlap0 != Imm64)
 	  {
 	    as_bad (_("no instruction mnemonic suffix given; can't determine immediate size"));
 	    return;
 	  }
       }
-    if ((overlap1 & (Imm8 | Imm8S | Imm16 | Imm32))
+    if ((overlap1 & (Imm8 | Imm8S | Imm16 | Imm32S | Imm32))
 	&& overlap1 != Imm8 && overlap1 != Imm8S
-	&& overlap1 != Imm16 && overlap1 != Imm32)
+        && overlap1 != Imm16 && overlap1 != Imm32S
+ 	&& overlap1 != Imm32 && overlap1 != Imm64)
       {
 	if (i.suffix)
 	  {
 	    overlap1 &= (i.suffix == BYTE_MNEM_SUFFIX ? (Imm8 | Imm8S) :
-			 (i.suffix == WORD_MNEM_SUFFIX ? Imm16 : Imm32));
+			(i.suffix == WORD_MNEM_SUFFIX ? Imm16 : 
+	 		(i.suffix == QWORD_MNEM_SUFFIX ? Imm64 | Imm32S : Imm32)));
 	  }
-	else if (overlap1 == (Imm16 | Imm32))
+	else if (overlap1 == (Imm16 | Imm32 | Imm32S)
+		 || overlap1 == (Imm16 | Imm32)
+		 || overlap1 == (Imm16 | Imm32S))
 	  {
 	    overlap1 =
-	      (flag_16bit_code ^ (i.prefix[DATA_PREFIX] != 0)) ? Imm16 : Imm32;
+	      ((flag_code == CODE_16BIT) ^ (i.prefix[DATA_PREFIX] != 0)) ? Imm16 : Imm32S;
 	  }
-	else
+	if (overlap1 != Imm8 && overlap1 != Imm8S
+	    && overlap1 != Imm16 && overlap1 != Imm32S
+	    && overlap1 != Imm32 && overlap1 != Imm64)
 	  {
-	    as_bad (_("no instruction mnemonic suffix given; can't determine immediate size"));
+	    as_bad (_("no instruction mnemonic suffix given; can't determine immediate size %x %c"),overlap1, i.suffix);
 	    return;
 	  }
       }
@@ -1931,7 +2177,8 @@ md_assemble (line)
 	/* Now select between word & dword operations via the operand
 	   size prefix, except for instructions that will ignore this
 	   prefix anyway.  */
-	if ((i.suffix == LONG_MNEM_SUFFIX) == flag_16bit_code
+	if (i.suffix != QWORD_MNEM_SUFFIX
+	    && (i.suffix == LONG_MNEM_SUFFIX) == (flag_code == CODE_16BIT)
 	    && !(i.tm.opcode_modifier & IgnoreSize))
 	  {
 	    unsigned int prefix = DATA_PREFIX_OPCODE;
@@ -1941,6 +2188,12 @@ md_assemble (line)
 	    if (! add_prefix (prefix))
 	      return;
 	  }
+
+	/* Set mode64 for an operand.  */
+	if (i.suffix == QWORD_MNEM_SUFFIX
+	    && !(i.tm.opcode_modifier & NoRex64))
+	    i.rex.mode64 = 1;
+
 	/* Size floating point instruction.  */
 	if (i.suffix == LONG_MNEM_SUFFIX)
 	  {
@@ -1995,6 +2248,8 @@ md_assemble (line)
 	    unsigned int op = (i.types[0] & (Reg | FloatReg)) ? 0 : 1;
 	    /* Register goes in low 3 bits of opcode.  */
 	    i.tm.base_opcode |= i.op[op].regs->reg_num;
+	    if (i.op[op].regs->reg_flags & RegRex)
+	      i.rex.extZ=1;
 	    if (!quiet_warnings && (i.tm.opcode_modifier & Ugh) != 0)
 	      {
 		/* Warn about some common errors, but press on regardless.
@@ -2045,11 +2300,19 @@ md_assemble (line)
 		  {
 		    i.rm.reg = i.op[dest].regs->reg_num;
 		    i.rm.regmem = i.op[source].regs->reg_num;
+		    if (i.op[dest].regs->reg_flags & RegRex)
+		      i.rex.extX=1;
+		    if (i.op[source].regs->reg_flags & RegRex)
+		      i.rex.extZ=1;
 		  }
 		else
 		  {
 		    i.rm.reg = i.op[source].regs->reg_num;
 		    i.rm.regmem = i.op[dest].regs->reg_num;
+		    if (i.op[dest].regs->reg_flags & RegRex)
+		      i.rex.extZ=1;
+		    if (i.op[source].regs->reg_flags & RegRex)
+		      i.rex.extX=1;
 		  }
 	      }
 	    else
@@ -2071,18 +2334,30 @@ md_assemble (line)
 			if (! i.index_reg)
 			  {
 			    /* Operand is just <disp>  */
-			    if (flag_16bit_code ^ (i.prefix[ADDR_PREFIX] != 0))
+			    if ((flag_code == CODE_16BIT) ^ (i.prefix[ADDR_PREFIX] != 0))
 			      {
 				i.rm.regmem = NO_BASE_REGISTER_16;
 				i.types[op] &= ~Disp;
 				i.types[op] |= Disp16;
 			      }
-			    else
+			    else if (flag_code != CODE_64BIT)
 			      {
 				i.rm.regmem = NO_BASE_REGISTER;
 				i.types[op] &= ~Disp;
 				i.types[op] |= Disp32;
 			      }
+			    else
+			      {
+			        /* 64bit mode overwrites the 32bit absolute addressing
+				   by RIP relative addressing and absolute addressing
+				   is encoded by one of the redundant SIB forms.  */
+
+				i.rm.regmem = ESCAPE_TO_TWO_BYTE_ADDRESSING;
+				i.sib.base = NO_BASE_REGISTER;
+				i.sib.index = NO_INDEX_REGISTER;
+				i.types[op] &= ~Disp;
+				i.types[op] |= Disp32S;
+			      }
 			  }
 			else /* ! i.base_reg && i.index_reg  */
 			  {
@@ -2091,9 +2366,22 @@ md_assemble (line)
 			    i.sib.scale = i.log2_scale_factor;
 			    i.rm.regmem = ESCAPE_TO_TWO_BYTE_ADDRESSING;
 			    i.types[op] &= ~Disp;
-			    i.types[op] |= Disp32;	/* Must be 32 bit.  */
+			    if (flag_code != CODE_64BIT)
+			      i.types[op] |= Disp32;	/* Must be 32 bit */
+			    else
+			      i.types[op] |= Disp32S;
+			    if (i.index_reg->reg_flags & RegRex)
+			      i.rex.extY=1;
 			  }
 		      }
+		    /* RIP addressing for 64bit mode.  */
+		    else if (i.base_reg->reg_type == BaseIndex)
+		      {
+			i.rm.regmem = NO_BASE_REGISTER;
+			i.types[op] &= ~Disp;
+			i.types[op] |= Disp32S;
+			i.flags[op] = Operand_PCrel;
+		      }
 		    else if (i.base_reg->reg_type & Reg16)
 		      {
 			switch (i.base_reg->reg_num)
@@ -2124,11 +2412,23 @@ md_assemble (line)
 			  }
 			i.rm.mode = mode_from_disp_size (i.types[op]);
 		      }
-		    else /* i.base_reg and 32 bit mode  */
+		    else /* i.base_reg and 32/64 bit mode  */
 		      {
+			if (flag_code == CODE_64BIT
+			    && (i.types[op] & Disp))
+			  {
+			    if (i.types[op] & Disp8)
+			      i.types[op] = Disp8 | Disp32S;
+			    else
+			      i.types[op] = Disp32S;
+			  }
 			i.rm.regmem = i.base_reg->reg_num;
+			if (i.base_reg->reg_flags & RegRex)
+			  i.rex.extZ=1;
 			i.sib.base = i.base_reg->reg_num;
-			if (i.base_reg->reg_num == EBP_REG_NUM)
+			/* x86-64 ignores REX prefix bit here to avoid
+			   decoder complications.  */
+			if ((i.base_reg->reg_num & 7) == EBP_REG_NUM)
 			  {
 			    default_seg = &ss;
 			    if (i.disp_operands == 0)
@@ -2162,6 +2462,8 @@ md_assemble (line)
 			  {
 			    i.sib.index = i.index_reg->reg_num;
 			    i.rm.regmem = ESCAPE_TO_TWO_BYTE_ADDRESSING;
+			    if (i.index_reg->reg_flags & RegRex)
+			      i.rex.extY=1;
 			  }
 			i.rm.mode = mode_from_disp_size (i.types[op]);
 		      }
@@ -2204,9 +2506,17 @@ md_assemble (line)
 		    /* If there is an extension opcode to put here, the
 		       register number must be put into the regmem field.  */
 		    if (i.tm.extension_opcode != None)
-		      i.rm.regmem = i.op[op].regs->reg_num;
+		      {
+			i.rm.regmem = i.op[op].regs->reg_num;
+			if (i.op[op].regs->reg_flags & RegRex)
+			  i.rex.extZ=1;
+		      }
 		    else
-		      i.rm.reg = i.op[op].regs->reg_num;
+		      {
+			i.rm.reg = i.op[op].regs->reg_num;
+			if (i.op[op].regs->reg_flags & RegRex)
+			  i.rex.extX=1;
+		      }
 
 		    /* Now, if no memory operand has set i.rm.mode = 0, 1, 2
 		       we must set it to 3 to indicate this is a register
@@ -2229,6 +2539,8 @@ md_assemble (line)
 		return;
 	      }
 	    i.tm.base_opcode |= (i.op[0].regs->reg_num << 3);
+	    if (i.op[0].regs->reg_flags & RegRex)
+	      i.rex.extZ = 1;
 	  }
 	else if ((i.tm.base_opcode & ~(D|W)) == MOV_AX_DISP32)
 	  {
@@ -2277,6 +2589,47 @@ md_assemble (line)
       i.op[0].disps->X_op = O_symbol;
     }
 
+  if (i.tm.opcode_modifier & Rex64)
+    i.rex.mode64 = 1;
+
+  /* For 8bit registers we would need an empty rex prefix.
+     Also in the case instruction is already having prefix,
+     we need to convert old registers to new ones.  */
+
+  if (((i.types[0] & Reg8) && (i.op[0].regs->reg_flags & RegRex64))
+      || ((i.types[1] & Reg8) && (i.op[1].regs->reg_flags & RegRex64))
+      || ((i.rex.mode64 || i.rex.extX || i.rex.extY || i.rex.extZ || i.rex.empty)
+	  && ((i.types[0] & Reg8) || (i.types[1] & Reg8))))
+    {
+      int x;
+      i.rex.empty=1;
+      for (x = 0; x < 2; x++)
+	{
+	  /* Look for 8bit operand that does use old registers.  */
+	  if (i.types[x] & Reg8
+	      && !(i.op[x].regs->reg_flags & RegRex64))
+	    {
+	      /* In case it is "hi" register, give up.  */
+	      if (i.op[x].regs->reg_num > 3)
+		as_bad (_("Can't encode registers '%%%s' in the instruction requiring REX prefix.\n"),
+			i.op[x].regs->reg_name);
+
+	      /* Otherwise it is equivalent to the extended register.
+	         Since the encoding don't change this is merely cosmetical
+	         cleanup for debug output.  */
+
+	      i.op[x].regs = i.op[x].regs + 8;
+	    }
+	}
+    }
+
+  if (i.rex.mode64 || i.rex.extX || i.rex.extY || i.rex.extZ || i.rex.empty)
+    add_prefix (0x40
+		| (i.rex.mode64 ? 8 : 0)
+		| (i.rex.extX ? 4 : 0)
+		| (i.rex.extY ? 2 : 0)
+		| (i.rex.extZ ? 1 : 0));
+
   /* We are ready to output the insn.  */
   {
     register char *p;
@@ -2289,7 +2642,7 @@ md_assemble (line)
 	int prefix;
 
 	code16 = 0;
-	if (flag_16bit_code)
+	if (flag_code == CODE_16BIT)
 	  code16 = CODE16;
 
 	prefix = 0;
@@ -2299,6 +2652,11 @@ md_assemble (line)
 	    i.prefixes -= 1;
 	    code16 ^= CODE16;
 	  }
+	if (i.prefix[REX_PREFIX])
+	  {
+	    prefix++;
+	    i.prefixes --;
+	  }
 
 	size = 4;
 	if (code16)
@@ -2316,8 +2674,10 @@ md_assemble (line)
 	insn_size += prefix + 1;
 	/* Prefix and 1 opcode byte go in fr_fix.  */
 	p = frag_more (prefix + 1);
-	if (prefix)
+	if (i.prefix[DATA_PREFIX])
 	  *p++ = DATA_PREFIX_OPCODE;
+	if (i.prefix[REX_PREFIX])
+	  *p++ = i.prefix[REX_PREFIX];
 	*p = i.tm.base_opcode;
 	/* 1 possible extra opcode + displacement go in var part.
 	   Pass reloc in fr_var.  */
@@ -2351,7 +2711,7 @@ md_assemble (line)
 	    int code16;
 
 	    code16 = 0;
-	    if (flag_16bit_code)
+	    if (flag_code == CODE_16BIT)
 	      code16 = CODE16;
 
 	    if (i.prefix[DATA_PREFIX])
@@ -2367,6 +2727,13 @@ md_assemble (line)
 	      size = 2;
 	  }
 
+	if (i.prefix[REX_PREFIX])
+	  {
+	    FRAG_APPEND_1_CHAR (i.prefix[REX_PREFIX]);
+	    insn_size++;
+	    i.prefixes -= 1;
+	  }
+
 	if (i.prefixes != 0 && !intel_syntax)
 	  as_warn (_("skipping prefixes on this instruction"));
 
@@ -2385,7 +2752,7 @@ md_assemble (line)
 	*p++ = i.tm.base_opcode & 0xff;
 
 	fix_new_exp (frag_now, p - frag_now->fr_literal, size,
-		     i.op[0].disps, 1, reloc (size, 1, i.disp_reloc[0]));
+		     i.op[0].disps, 1, reloc (size, 1, 1, i.disp_reloc[0]));
       }
     else if (i.tm.opcode_modifier & JumpInterSegment)
       {
@@ -2394,7 +2761,7 @@ md_assemble (line)
 	int code16;
 
 	code16 = 0;
-	if (flag_16bit_code)
+	if (flag_code == CODE_16BIT)
 	  code16 = CODE16;
 
 	prefix = 0;
@@ -2404,6 +2771,11 @@ md_assemble (line)
 	    i.prefixes -= 1;
 	    code16 ^= CODE16;
 	  }
+	if (i.prefix[REX_PREFIX])
+	  {
+	    prefix++;
+	    i.prefixes -= 1;
+	  }
 
 	size = 4;
 	if (code16)
@@ -2415,8 +2787,13 @@ md_assemble (line)
 	/* 1 opcode; 2 segment; offset  */
 	insn_size += prefix + 1 + 2 + size;
 	p = frag_more (prefix + 1 + 2 + size);
-	if (prefix)
+
+	if (i.prefix[DATA_PREFIX])
 	  *p++ = DATA_PREFIX_OPCODE;
+
+	if (i.prefix[REX_PREFIX])
+	  *p++ = i.prefix[REX_PREFIX];
+
 	*p++ = i.tm.base_opcode;
 	if (i.op[1].imms->X_op == O_constant)
 	  {
@@ -2433,7 +2810,7 @@ md_assemble (line)
 	  }
 	else
 	  fix_new_exp (frag_now, p - frag_now->fr_literal, size,
-		       i.op[1].imms, 0, reloc (size, 0, i.disp_reloc[0]));
+		       i.op[1].imms, 0, reloc (size, 0, 0, i.disp_reloc[0]));
 	if (i.op[0].imms->X_op != O_constant)
 	  as_bad (_("can't handle non absolute segment in `%s'"),
 		  i.tm.name);
@@ -2531,11 +2908,13 @@ md_assemble (line)
 			offsetT val;
 
 			size = 4;
-			if (i.types[n] & (Disp8 | Disp16))
+			if (i.types[n] & (Disp8 | Disp16 | Disp64))
 			  {
 			    size = 2;
 			    if (i.types[n] & Disp8)
 			      size = 1;
+			    if (i.types[n] & Disp64)
+			      size = 8;
 			  }
 			val = offset_in_range (i.op[n].disps->X_add_number,
 					       size);
@@ -2546,15 +2925,51 @@ md_assemble (line)
 		    else
 		      {
 			int size = 4;
+			int sign = 0;
+			int pcrel = (i.flags[n] & Operand_PCrel) != 0;
+
+			/* The PC relative address is computed relative
+			   to the instruction boundary, so in case immediate
+			   fields follows, we need to adjust the value.  */
+			if (pcrel && i.imm_operands)
+			  {
+			    int imm_size = 4;
+			    register unsigned int n1;
+
+			    for (n1 = 0; n1 < i.operands; n1++)
+			      if (i.types[n1] & Imm)
+				{
+				  if (i.types[n1] & (Imm8 | Imm8S | Imm16 | Imm64))
+				    {
+				      imm_size = 2;
+				      if (i.types[n1] & (Imm8 | Imm8S))
+					imm_size = 1;
+				      if (i.types[n1] & Imm64)
+					imm_size = 8;
+				    }
+				  break;
+				}
+			    /* We should find the immediate.  */
+			    if (n1 == i.operands)
+			      abort();
+			    i.op[n].disps->X_add_number -= imm_size;
+			  }
 
-			if (i.types[n] & Disp16)
-			  size = 2;
+			if (i.types[n] & Disp32S)
+			  sign = 1;
+
+		        if (i.types[n] & (Disp16 | Disp64))
+			  {
+			    size = 2;
+			    if (i.types[n] & Disp64)
+			      size = 8;
+			  }
 
 			insn_size += size;
 			p = frag_more (size);
 			fix_new_exp (frag_now, p - frag_now->fr_literal, size,
-				     i.op[n].disps, 0,
-				     reloc (size, 0, i.disp_reloc[n]));
+				     i.op[n].disps, pcrel,
+				     reloc (size, pcrel, sign, i.disp_reloc[n]));
 		      }
 		  }
 	      }
@@ -2575,11 +2990,13 @@ md_assemble (line)
 			offsetT val;
 
 			size = 4;
-			if (i.types[n] & (Imm8 | Imm8S | Imm16))
+			if (i.types[n] & (Imm8 | Imm8S | Imm16 | Imm64))
 			  {
 			    size = 2;
 			    if (i.types[n] & (Imm8 | Imm8S))
 			      size = 1;
+			    else if (i.types[n] & Imm64)
+			      size = 8;
 			  }
 			val = offset_in_range (i.op[n].imms->X_add_number,
 					       size);
@@ -2599,15 +3016,23 @@ md_assemble (line)
 			int reloc_type;
 #endif
 			int size = 4;
+			int sign = 0;
 
-			if (i.types[n] & Imm16)
-			  size = 2;
-			else if (i.types[n] & (Imm8 | Imm8S))
-			  size = 1;
+			if ((i.types[n] & (Imm32S))
+			    && i.suffix == QWORD_MNEM_SUFFIX)
+			  sign = 1;
+			if (i.types[n] & (Imm8 | Imm8S | Imm16 | Imm64))
+			  {
+			    size = 2;
+			    if (i.types[n] & (Imm8 | Imm8S))
+			      size = 1;
+			    if (i.types[n] & Imm64)
+			      size = 8;
+			  }
 
 			insn_size += size;
 			p = frag_more (size);
-			reloc_type = reloc (size, 0, i.disp_reloc[0]);
+			reloc_type = reloc (size, 0, sign, i.disp_reloc[0]);
 #ifdef BFD_ASSEMBLER
 			if (reloc_type == BFD_RELOC_32
 			    && GOT_symbol
@@ -2618,6 +3043,9 @@ md_assemble (line)
 					 (i.op[n].imms->X_op_symbol)->X_op)
 					== O_subtract))))
 			  {
+			    /* We don't support dynamic linking on x86-64 yet.  */
+			    if (flag_code == CODE_64BIT)
+			      abort();
 			    reloc_type = BFD_RELOC_386_GOTPC;
 			    i.op[n].imms->X_add_number += 3;
 			  }
@@ -2682,7 +3110,7 @@ i386_immediate (imm_start)
 	int first;
 
 	/* GOT relocations are not supported in 16 bit mode.  */
-	if (flag_16bit_code)
+	if (flag_code == CODE_16BIT)
 	  as_bad (_("GOT relocations not supported in 16 bit mode"));
 
 	if (GOT_symbol == NULL)
@@ -2690,17 +3118,33 @@ i386_immediate (imm_start)
 
 	if (strncmp (cp + 1, "PLT", 3) == 0)
 	  {
-	    i.disp_reloc[this_operand] = BFD_RELOC_386_PLT32;
+	    if (flag_code == CODE_64BIT)
+	      i.disp_reloc[this_operand] = BFD_RELOC_X86_64_PLT32;
+	    else
+	      i.disp_reloc[this_operand] = BFD_RELOC_386_PLT32;
 	    len = 3;
 	  }
 	else if (strncmp (cp + 1, "GOTOFF", 6) == 0)
 	  {
+	    if (flag_code == CODE_64BIT)
+	      as_bad ("GOTOFF relocations are unsupported in 64bit mode.");
 	    i.disp_reloc[this_operand] = BFD_RELOC_386_GOTOFF;
 	    len = 6;
 	  }
 	else if (strncmp (cp + 1, "GOT", 3) == 0)
 	  {
-	    i.disp_reloc[this_operand] = BFD_RELOC_386_GOT32;
+	    if (flag_code == CODE_64BIT)
+	      i.disp_reloc[this_operand] = BFD_RELOC_X86_64_GOT32;
+	    else
+	      i.disp_reloc[this_operand] = BFD_RELOC_386_GOT32;
+	    len = 3;
+	  }
+	else if (strncmp (cp + 1, "GOTPCREL", 3) == 0)
+	  {
+	    if (flag_code == CODE_64BIT)
+	      i.disp_reloc[this_operand] = BFD_RELOC_X86_64_GOTPCREL;
+	    else
+	      as_bad ("GOTPCREL relocations are supported only in 64bit mode.");
 	    len = 3;
 	  }
 	else
@@ -2736,11 +3180,14 @@ i386_immediate (imm_start)
       exp->X_add_symbol = (symbolS *) 0;
       exp->X_op_symbol = (symbolS *) 0;
     }
-
-  if (exp->X_op == O_constant)
+  else if (exp->X_op == O_constant)
     {
       /* Size it properly later.  */
-      i.types[this_operand] |= Imm32;
+      i.types[this_operand] |= Imm64;
+      /* If BFD64, sign extend val.  */
+      if (!use_rela_relocations)
+	if ((exp->X_add_number & ~(((addressT) 2 << 31) - 1)) == 0)
+	  exp->X_add_number = (exp->X_add_number ^ ((addressT) 1 << 31)) - ((addressT) 1 << 31);
     }
 #if (defined (OBJ_AOUT) || defined (OBJ_MAYBE_AOUT))
   else if (1
@@ -2768,10 +3215,8 @@ i386_immediate (imm_start)
     {
       /* This is an address.  The size of the address will be
 	 determined later, depending on destination register,
-	 suffix, or the default for the section.  We exclude
-	 Imm8S here so that `push $foo' and other instructions
-	 with an Imm8S form will use Imm16 or Imm32.  */
-      i.types[this_operand] |= (Imm8 | Imm16 | Imm32);
+	 suffix, or the default for the section.  */
+      i.types[this_operand] |= Imm8 | Imm16 | Imm32 | Imm32S | Imm64;
     }
 
   return 1;
@@ -2830,8 +3275,10 @@ i386_displacement (disp_start, disp_end)
   char *save_input_line_pointer;
   int bigdisp = Disp32;
 
-  if (flag_16bit_code ^ (i.prefix[ADDR_PREFIX] != 0))
+  if ((flag_code == CODE_16BIT) ^ (i.prefix[ADDR_PREFIX] != 0))
     bigdisp = Disp16;
+  if (flag_code == CODE_64BIT)
+    bigdisp = Disp64;
   i.types[this_operand] |= bigdisp;
 
   exp = &disp_expressions[i.disp_operands];
@@ -2901,7 +3348,7 @@ i386_displacement (disp_start, disp_end)
 	int first;
 
 	/* GOT relocations are not supported in 16 bit mode.  */
-	if (flag_16bit_code)
+	if (flag_code == CODE_16BIT)
 	  as_bad (_("GOT relocations not supported in 16 bit mode"));
 
 	if (GOT_symbol == NULL)
@@ -2909,17 +3356,32 @@ i386_displacement (disp_start, disp_end)
 
 	if (strncmp (cp + 1, "PLT", 3) == 0)
 	  {
-	    i.disp_reloc[this_operand] = BFD_RELOC_386_PLT32;
+	    if (flag_code == CODE_64BIT)
+	      i.disp_reloc[this_operand] = BFD_RELOC_X86_64_PLT32;
+	    else
+	      i.disp_reloc[this_operand] = BFD_RELOC_386_PLT32;
 	    len = 3;
 	  }
 	else if (strncmp (cp + 1, "GOTOFF", 6) == 0)
 	  {
+	    if (flag_code == CODE_64BIT)
+	      as_bad ("GOTOFF relocation is not supported in 64bit mode.");
 	    i.disp_reloc[this_operand] = BFD_RELOC_386_GOTOFF;
 	    len = 6;
 	  }
 	else if (strncmp (cp + 1, "GOT", 3) == 0)
 	  {
-	    i.disp_reloc[this_operand] = BFD_RELOC_386_GOT32;
+	    if (flag_code == CODE_64BIT)
+	      i.disp_reloc[this_operand] = BFD_RELOC_X86_64_GOT32;
+	    else
+	      i.disp_reloc[this_operand] = BFD_RELOC_386_GOT32;
+	    len = 3;
+	  }
+	else if (strncmp (cp + 1, "GOTPCREL", 3) == 0)
+	  {
+	    if (flag_code != CODE_64BIT)
+	      as_bad ("GOTPCREL relocation is supported only in 64bit mode.");
+	    i.disp_reloc[this_operand] = BFD_RELOC_X86_64_GOTPCREL;
 	    len = 3;
 	  }
 	else
@@ -2943,7 +3405,8 @@ i386_displacement (disp_start, disp_end)
   /* We do this to make sure that the section symbol is in
      the symbol table.  We will ultimately change the relocation
      to be relative to the beginning of the section.  */
-  if (i.disp_reloc[this_operand] == BFD_RELOC_386_GOTOFF)
+  if (i.disp_reloc[this_operand] == BFD_RELOC_386_GOTOFF
+      || i.disp_reloc[this_operand] == BFD_RELOC_X86_64_GOTPCREL)
     {
       if (S_IS_LOCAL(exp->X_add_symbol)
 	  && S_GET_SEGMENT (exp->X_add_symbol) != undefined_section)
@@ -2994,6 +3457,8 @@ i386_displacement (disp_start, disp_end)
       return 0;
     }
 #endif
+  else if (flag_code == CODE_64BIT)
+    i.types[this_operand] |= Disp32S | Disp32;
   return 1;
 }
 
@@ -3006,32 +3471,58 @@ static int
 i386_index_check (operand_string)
      const char *operand_string;
 {
+  int ok;
 #if INFER_ADDR_PREFIX
   int fudged = 0;
 
  tryprefix:
 #endif
-  if (flag_16bit_code ^ (i.prefix[ADDR_PREFIX] != 0)
-      /* 16 bit mode checks.  */
-      ? ((i.base_reg
-	  && ((i.base_reg->reg_type & (Reg16|BaseIndex))
-	      != (Reg16|BaseIndex)))
-	 || (i.index_reg
-	     && (((i.index_reg->reg_type & (Reg16|BaseIndex))
-		  != (Reg16|BaseIndex))
-		 || ! (i.base_reg
-		       && i.base_reg->reg_num < 6
-		       && i.index_reg->reg_num >= 6
-		       && i.log2_scale_factor == 0))))
-      /* 32 bit mode checks.  */
-      : ((i.base_reg
-	  && (i.base_reg->reg_type & Reg32) == 0)
-	 || (i.index_reg
-	     && ((i.index_reg->reg_type & (Reg32|BaseIndex))
-		 != (Reg32|BaseIndex)))))
+  ok = 1;
+  if (flag_code == CODE_64BIT)
+    {
+      /* 64bit checks.  */
+      if ((i.base_reg
+	   && ((i.base_reg->reg_type & Reg64) == 0)
+	       && (i.base_reg->reg_type != BaseIndex
+		   || i.index_reg))
+	  || (i.index_reg
+	      && ((i.index_reg->reg_type & (Reg64|BaseIndex))
+		  != (Reg64|BaseIndex))))
+	ok = 0;
+    }
+  else
+    {
+      if ((flag_code == CODE_16BIT) ^ (i.prefix[ADDR_PREFIX] != 0))
+	{
+	  /* 16bit checks.  */
+	  if ((i.base_reg
+	       && ((i.base_reg->reg_type & (Reg16|BaseIndex|RegRex))
+		   != (Reg16|BaseIndex)))
+	      || (i.index_reg
+		  && (((i.index_reg->reg_type & (Reg16|BaseIndex))
+		       != (Reg16|BaseIndex))
+		      || ! (i.base_reg
+			    && i.base_reg->reg_num < 6
+			    && i.index_reg->reg_num >= 6
+			    && i.log2_scale_factor == 0))))
+	    ok = 0;
+	}
+      else
+        {
+	  /* 32bit checks.  */
+	  if ((i.base_reg
+	       && (i.base_reg->reg_type & (Reg32 | RegRex)) != Reg32)
+	      || (i.index_reg
+		  && ((i.index_reg->reg_type & (Reg32|BaseIndex|RegRex))
+		      != (Reg32|BaseIndex))))
+	   ok = 0;
+	}
+    }
+  if (!ok)
     {
 #if INFER_ADDR_PREFIX
-      if (i.prefix[ADDR_PREFIX] == 0 && stackop_size != '\0')
+      if (flag_code != CODE_64BIT
+	  && i.prefix[ADDR_PREFIX] == 0 && stackop_size != '\0')
 	{
 	  i.prefix[ADDR_PREFIX] = ADDR_PREFIX_OPCODE;
 	  i.prefixes += 1;
@@ -3052,7 +3543,7 @@ i386_index_check (operand_string)
 #endif
 	as_bad (_("`%s' is not a valid %s bit base/index expression"),
 		operand_string,
-		flag_16bit_code ^ (i.prefix[ADDR_PREFIX] != 0) ? "16" : "32");
+		flag_code_names[flag_code]);
       return 0;
     }
   return 1;
@@ -3651,6 +4142,7 @@ md_apply_fix3 (fixP, valp, seg)
     switch (fixP->fx_r_type)
       {
       case BFD_RELOC_386_PLT32:
+      case BFD_RELOC_X86_64_PLT32:
 	/* Make the jump instruction point to the address of the operand.  At
 	   runtime we merely add the offset to the actual PLT entry.  */
 	value = -4;
@@ -3698,9 +4190,11 @@ md_apply_fix3 (fixP, valp, seg)
 	value -= 1;
 	break;
       case BFD_RELOC_386_GOT32:
+      case BFD_RELOC_X86_64_GOT32:
 	value = 0; /* Fully resolved at runtime.  No addend.  */
 	break;
       case BFD_RELOC_386_GOTOFF:
+      case BFD_RELOC_X86_64_GOTPCREL:
 	break;
 
       case BFD_RELOC_VTABLE_INHERIT:
@@ -3714,7 +4208,20 @@ md_apply_fix3 (fixP, valp, seg)
 #endif /* defined (OBJ_ELF) || defined (OBJ_MAYBE_ELF)  */
   *valp = value;
 #endif /* defined (BFD_ASSEMBLER) && !defined (TE_Mach)  */
+
+#ifndef BFD_ASSEMBLER
   md_number_to_chars (p, value, fixP->fx_size);
+#else
+  /* Are we finished with this relocation now?  */
+  if (fixP->fx_addsy == 0 && fixP->fx_pcrel == 0)
+    fixP->fx_done = 1;
+  else if (use_rela_relocations)
+    {
+      fixP->fx_no_overflow = 1;
+      value = 0;
+    }
+  md_number_to_chars (p, value, fixP->fx_size);
+#endif
 
   return 1;
 }
@@ -3859,6 +4366,10 @@ const char *md_shortopts = "kVQ:sq";
 const char *md_shortopts = "q";
 #endif
 struct option md_longopts[] = {
+#define OPTION_32 (OPTION_MD_BASE + 0)
+  {"32", no_argument, NULL, OPTION_32},
+#define OPTION_64 (OPTION_MD_BASE + 1)
+  {"64", no_argument, NULL, OPTION_64},
   {NULL, no_argument, NULL, 0}
 };
 size_t md_longopts_size = sizeof (md_longopts);
@@ -3894,6 +4405,34 @@ md_parse_option (c, arg)
          .stab instead of .stab.excl.  We always use .stab anyhow.  */
       break;
 #endif
+#ifdef OBJ_ELF
+    case OPTION_32:
+    case OPTION_64:
+      {
+	const char **list, **l;
+
+	default_arch = c == OPTION_32 ? "i386" : "x86_64";
+	list = bfd_target_list ();
+	for (l = list; *l != NULL; l++)
+	  {
+	    if (c == OPTION_32)
+	      {
+		if (strcmp (*l, "elf32-i386") == 0)
+		  break;
+	      }
+	    else
+	      {
+		if (strcmp (*l, "elf64-x86-64") == 0)
+		  break;
+	      }
+	  }
+	if (*l == NULL)
+	  as_fatal (_("No compiled in support for %d bit object file format"),
+		    c == OPTION_32 ? 32 : 64);
+	free (list);
+      }
+      break;
+#endif
 
     default:
       return 0;
@@ -3919,15 +4458,20 @@ md_show_usage (stream)
 }
 
 #ifdef BFD_ASSEMBLER
-#if ((defined (OBJ_MAYBE_ELF) && defined (OBJ_MAYBE_COFF)) \
-     || (defined (OBJ_MAYBE_ELF) && defined (OBJ_MAYBE_AOUT)) \
-     || (defined (OBJ_MAYBE_COFF) && defined (OBJ_MAYBE_AOUT)))
+#if ((defined (OBJ_MAYBE_COFF) && defined (OBJ_MAYBE_AOUT)) \
+     || defined (OBJ_ELF) || defined (OBJ_MAYBE_ELF))
 
 /* Pick the target format to use.  */
 
 const char *
 i386_target_format ()
 {
+  if (!strcmp (default_arch, "x86_64"))
+    set_code_flag (CODE_64BIT);
+  else if (!strcmp (default_arch, "i386"))
+    set_code_flag (CODE_32BIT);
+  else
+    as_fatal (_("Unknown architecture"));
   switch (OUTPUT_FLAVOR)
     {
 #ifdef OBJ_MAYBE_AOUT
@@ -3938,9 +4482,13 @@ i386_target_format ()
     case bfd_target_coff_flavour:
       return "coff-i386";
 #endif
-#ifdef OBJ_MAYBE_ELF
+#if defined (OBJ_MAYBE_ELF) || defined (OBJ_ELF)
     case bfd_target_elf_flavour:
-      return "elf32-i386";
+      {
+	 if (flag_code == CODE_64BIT)
+	   use_rela_relocations = 1;
+         return flag_code == CODE_64BIT ? "elf64-x86-64" : "elf32-i386";
+      }
 #endif
     default:
       abort ();
@@ -4033,6 +4581,9 @@ i386_validate_fix (fixp)
 {
   if (fixp->fx_subsy && fixp->fx_subsy == GOT_symbol)
     {
+      /* GOTOFF relocation are nonsense in 64bit mode.  */
+      if (flag_code == CODE_64BIT)
+	abort();
       fixp->fx_r_type = BFD_RELOC_386_GOTOFF;
       fixp->fx_subsy = 0;
     }
@@ -4048,10 +4599,14 @@ tc_gen_reloc (section, fixp)
 
   switch (fixp->fx_r_type)
     {
+    case BFD_RELOC_X86_64_PLT32:
+    case BFD_RELOC_X86_64_GOT32:
+    case BFD_RELOC_X86_64_GOTPCREL:
     case BFD_RELOC_386_PLT32:
     case BFD_RELOC_386_GOT32:
     case BFD_RELOC_386_GOTOFF:
     case BFD_RELOC_386_GOTPC:
+    case BFD_RELOC_X86_64_32S:
     case BFD_RELOC_RVA:
     case BFD_RELOC_VTABLE_ENTRY:
     case BFD_RELOC_VTABLE_INHERIT:
@@ -4083,6 +4638,7 @@ tc_gen_reloc (section, fixp)
 	    case 1: code = BFD_RELOC_8;  break;
 	    case 2: code = BFD_RELOC_16; break;
 	    case 4: code = BFD_RELOC_32; break;
+	    case 8: code = BFD_RELOC_64; break;
 	    }
 	}
       break;
@@ -4091,22 +4647,47 @@ tc_gen_reloc (section, fixp)
   if (code == BFD_RELOC_32
       && GOT_symbol
       && fixp->fx_addsy == GOT_symbol)
-    code = BFD_RELOC_386_GOTPC;
+    {
+      /* We don't support GOTPC on 64bit targets.  */
+      if (flag_code == CODE_64BIT)
+	abort();
+      code = BFD_RELOC_386_GOTPC;
+    }
 
   rel = (arelent *) xmalloc (sizeof (arelent));
   rel->sym_ptr_ptr = (asymbol **) xmalloc (sizeof (asymbol *));
   *rel->sym_ptr_ptr = symbol_get_bfdsym (fixp->fx_addsy);
 
   rel->address = fixp->fx_frag->fr_address + fixp->fx_where;
-  /* HACK: Since i386 ELF uses Rel instead of Rela, encode the
-     vtable entry to be used in the relocation's section offset.  */
-  if (fixp->fx_r_type == BFD_RELOC_VTABLE_ENTRY)
-    rel->address = fixp->fx_offset;
+  if (!use_rela_relocations)
+    {
+      /* HACK: Since i386 ELF uses Rel instead of Rela, encode the
+	 vtable entry to be used in the relocation's section offset.  */
+      if (fixp->fx_r_type == BFD_RELOC_VTABLE_ENTRY)
+	rel->address = fixp->fx_offset;
 
-  if (fixp->fx_pcrel)
-    rel->addend = fixp->fx_addnumber;
+      if (fixp->fx_pcrel)
+	rel->addend = fixp->fx_addnumber;
+      else
+	rel->addend = 0;
+    }
+  /* Use the rela in 64bit mode.  */
   else
-    rel->addend = 0;
+    {
+      rel->addend = fixp->fx_offset;
+#ifdef OBJ_ELF
+      /* Ohhh, this is ugly.  The problem is that if this is a local global
+         symbol, the relocation will entirely be performed at link time, not
+         at assembly time.  bfd_perform_reloc doesn't know about this sort
+         of thing, and as a result we need to fake it out here.  */
+      if ((S_IS_EXTERN (fixp->fx_addsy) || S_IS_WEAK (fixp->fx_addsy))
+	  && !S_IS_COMMON(fixp->fx_addsy))
+	rel->addend -= symbol_get_bfdsym (fixp->fx_addsy)->value;
+#endif
+      if (fixp->fx_pcrel)
+	rel->addend -= fixp->fx_size;
+    }
+
 
   rel->howto = bfd_reloc_type_lookup (stdoutput, code);
   if (rel->howto == NULL)
@@ -4564,11 +5145,7 @@ intel_e09_1 ()
 	  if (intel_parser.got_a_float == 1)	/* "f..." */
 	    i.suffix = LONG_MNEM_SUFFIX;
 	  else
-	    {
-	      as_bad (_("operand modifier `%s' supported only for i387 operations\n"),
-		      prev_token.str);
-	      return 0;
-	    }
+	    i.suffix = QWORD_MNEM_SUFFIX;
 	}
 
       else if (prev_token.code == T_XWORD)
diff --git a/gas/config/tc-i386.h b/gas/config/tc-i386.h
index 5d48102..3c2efbf 100644
--- a/gas/config/tc-i386.h
+++ b/gas/config/tc-i386.h
@@ -101,9 +101,8 @@ extern int tc_i386_fix_adjustable PARAMS ((struct fix *));
 #define AOUT_TARGET_FORMAT	"a.out-i386"
 #endif
 
-#if ((defined (OBJ_MAYBE_ELF) && defined (OBJ_MAYBE_COFF)) \
-     || (defined (OBJ_MAYBE_ELF) && defined (OBJ_MAYBE_AOUT)) \
-     || (defined (OBJ_MAYBE_COFF) && defined (OBJ_MAYBE_AOUT)))
+#if ((defined (OBJ_MAYBE_COFF) && defined (OBJ_MAYBE_AOUT)) \
+     || defined (OBJ_ELF) || defined (OBJ_MAYBE_ELF))
 extern const char *i386_target_format PARAMS ((void));
 #define TARGET_FORMAT i386_target_format ()
 #else
@@ -202,7 +201,8 @@ extern const char extra_symbol_chars[];
 #define ADDR_PREFIX	2
 #define DATA_PREFIX	3
 #define SEG_PREFIX	4
-#define MAX_PREFIXES	5	/* max prefixes per opcode */
+#define REX_PREFIX	5       /* must come last.  */
+#define MAX_PREFIXES	6	/* max prefixes per opcode */
 
 /* we define the syntax here (modulo base,index,scale syntax) */
 #define REGISTER_PREFIX '%'
@@ -229,6 +229,7 @@ extern const char extra_symbol_chars[];
 #define BYTE_MNEM_SUFFIX  'b'
 #define SHORT_MNEM_SUFFIX 's'
 #define LONG_MNEM_SUFFIX  'l'
+#define QWORD_MNEM_SUFFIX  'q'
 /* Intel Syntax */
 #define LONG_DOUBLE_MNEM_SUFFIX 'x'
 
@@ -278,9 +279,20 @@ typedef struct
 #define Cpu486		 0x10	/* i486 or better required */
 #define Cpu586		 0x20	/* i585 or better required */
 #define Cpu686		 0x40	/* i686 or better required */
-#define CpuMMX		 0x80	/* MMX support required */
-#define CpuSSE		0x100	/* Streaming SIMD extensions required */
-#define Cpu3dnow	0x200	/* 3dnow! support required */
+#define CpuK6		 0x80	/* AMD K6 or better required*/
+#define CpuAthlon	0x100	/* AMD Athlon or better required*/
+#define CpuSledgehammer 0x200	/* Sledgehammer or better required */
+#define CpuMMX		0x400	/* MMX support required */
+#define CpuSSE		0x800	/* Streaming SIMD extensions required */
+#define Cpu3dnow       0x1000	/* 3dnow! support required */
+#define CpuUnknown     0x2000	/* The CPU is unknown,  be on the safe side.  */
+
+  /* These flags are set by gas depending on the flag_code.  */
+#define Cpu64	     0x4000000   /* 64bit support required  */
+#define CpuNo64      0x8000000   /* Not supported in the 64bit mode  */
+
+  /* The default value for unknown CPUs - enable all features to avoid problems.  */
+#define CpuUnknownFlags (Cpu086|Cpu186|Cpu286|Cpu386|Cpu486|Cpu586|Cpu686|CpuSledgehammer|CpuMMX|CpuSSE|Cpu3dnow|CpuK6|CpuAthlon)
 
   /* the bits in opcode_modifier are used to generate the final opcode from
      the base_opcode.  These bits also are used to detect alternate forms of
@@ -305,19 +317,23 @@ typedef struct
 #define Seg3ShortForm	0x1000	/* fs/gs segment register insns.  */
 #define Size16		0x2000	/* needs size prefix if in 32-bit mode */
 #define Size32		0x4000	/* needs size prefix if in 16-bit mode */
-#define IgnoreSize	0x8000  /* instruction ignores operand size prefix */
-#define DefaultSize    0x10000  /* default insn size depends on mode */
-#define No_bSuf	       0x20000	/* b suffix on instruction illegal */
-#define No_wSuf	       0x40000	/* w suffix on instruction illegal */
-#define No_lSuf	       0x80000	/* l suffix on instruction illegal */
-#define No_sSuf	      0x100000	/* s suffix on instruction illegal */
-#define No_xSuf       0x200000  /* x suffix on instruction illegal */
-#define FWait	      0x400000	/* instruction needs FWAIT */
-#define IsString      0x800000	/* quick test for string instructions */
-#define regKludge    0x1000000	/* fake an extra reg operand for clr, imul */
-#define IsPrefix     0x2000000	/* opcode is a prefix */
-#define ImmExt	     0x4000000	/* instruction has extension in 8 bit imm */
-#define Ugh	     0x8000000	/* deprecated fp insn, gets a warning */
+#define Size64		0x8000	/* needs size prefix if in 16-bit mode */
+#define IgnoreSize     0x10000  /* instruction ignores operand size prefix */
+#define DefaultSize    0x20000  /* default insn size depends on mode */
+#define No_bSuf	       0x40000	/* b suffix on instruction illegal */
+#define No_wSuf	       0x80000	/* w suffix on instruction illegal */
+#define No_lSuf	      0x100000 	/* l suffix on instruction illegal */
+#define No_sSuf	      0x200000	/* s suffix on instruction illegal */
+#define No_qSuf       0x400000  /* q suffix on instruction illegal */
+#define No_xSuf       0x800000  /* x suffix on instruction illegal */
+#define FWait	     0x1000000	/* instruction needs FWAIT */
+#define IsString     0x2000000	/* quick test for string instructions */
+#define regKludge    0x4000000	/* fake an extra reg operand for clr, imul */
+#define IsPrefix     0x8000000	/* opcode is a prefix */
+#define ImmExt	    0x10000000	/* instruction has extension in 8 bit imm */
+#define NoRex64	    0x20000000  /* instruction don't need Rex64 prefix.  */
+#define Rex64	    0x40000000  /* instruction require Rex64 prefix.  */
+#define Ugh	    0x80000000	/* deprecated fp insn, gets a warning */
 
   /* operand_types[i] describes the type of operand i.  This is made
      by OR'ing together all of the possible type masks.  (e.g.
@@ -330,51 +346,58 @@ typedef struct
 #define Reg8		   0x1	/* 8 bit reg */
 #define Reg16		   0x2	/* 16 bit reg */
 #define Reg32		   0x4	/* 32 bit reg */
+#define Reg64		   0x8	/* 64 bit reg */
   /* immediate */
-#define Imm8		   0x8	/* 8 bit immediate */
-#define Imm8S		  0x10	/* 8 bit immediate sign extended */
-#define Imm16		  0x20	/* 16 bit immediate */
-#define Imm32		  0x40	/* 32 bit immediate */
-#define Imm1		  0x80	/* 1 bit immediate */
+#define Imm8		  0x10	/* 8 bit immediate */
+#define Imm8S		  0x20	/* 8 bit immediate sign extended */
+#define Imm16		  0x40	/* 16 bit immediate */
+#define Imm32		  0x80	/* 32 bit immediate */
+#define Imm32S		 0x100	/* 32 bit immediate sign extended */
+#define Imm64		 0x200	/* 64 bit immediate */
+#define Imm1		 0x400	/* 1 bit immediate */
   /* memory */
-#define BaseIndex	 0x100
+#define BaseIndex	 0x800
   /* Disp8,16,32 are used in different ways, depending on the
      instruction.  For jumps, they specify the size of the PC relative
      displacement, for baseindex type instructions, they specify the
      size of the offset relative to the base register, and for memory
      offset instructions such as `mov 1234,%al' they specify the size of
      the offset relative to the segment base.  */
-#define Disp8		 0x200	/* 8 bit displacement */
-#define Disp16		 0x400	/* 16 bit displacement */
-#define Disp32		 0x800	/* 32 bit displacement */
+#define Disp8		0x1000	/* 8 bit displacement */
+#define Disp16		0x2000	/* 16 bit displacement */
+#define Disp32		0x4000	/* 32 bit displacement */
+#define Disp32S	        0x8000	/* 32 bit signed displacement */
+#define Disp64	       0x10000	/* 64 bit displacement */
   /* specials */
-#define InOutPortReg	0x1000	/* register to hold in/out port addr = dx */
-#define ShiftCount	0x2000	/* register to hold shift cound = cl */
-#define Control	        0x4000	/* Control register */
-#define Debug	        0x8000	/* Debug register */
-#define Test	       0x10000	/* Test register */
-#define FloatReg       0x20000	/* Float register */
-#define FloatAcc       0x40000	/* Float stack top %st(0) */
-#define SReg2	       0x80000	/* 2 bit segment register */
-#define SReg3	      0x100000	/* 3 bit segment register */
-#define Acc	      0x200000	/* Accumulator %al or %ax or %eax */
-#define JumpAbsolute  0x400000
-#define RegMMX	      0x800000	/* MMX register */
-#define RegXMM	     0x1000000	/* XMM registers in PIII */
-#define EsSeg	     0x2000000	/* String insn operand with fixed es segment */
+#define InOutPortReg   0x20000	/* register to hold in/out port addr = dx */
+#define ShiftCount     0x40000	/* register to hold shift cound = cl */
+#define Control	       0x80000	/* Control register */
+#define Debug	      0x100000	/* Debug register */
+#define Test	      0x200000	/* Test register */
+#define FloatReg      0x400000	/* Float register */
+#define FloatAcc      0x800000	/* Float stack top %st(0) */
+#define SReg2	     0x1000000	/* 2 bit segment register */
+#define SReg3	     0x2000000	/* 3 bit segment register */
+#define Acc	     0x4000000	/* Accumulator %al or %ax or %eax */
+#define JumpAbsolute 0x8000000
+#define RegMMX	    0x10000000	/* MMX register */
+#define RegXMM	    0x20000000	/* XMM registers in PIII */
+#define EsSeg	    0x40000000	/* String insn operand with fixed es segment */
+
   /* InvMem is for instructions with a modrm byte that only allow a
      general register encoding in the i.tm.mode and i.tm.regmem fields,
      eg. control reg moves.  They really ought to support a memory form,
      but don't, so we add an InvMem flag to the register operand to
      indicate that it should be encoded in the i.tm.regmem field.  */
-#define InvMem	     0x4000000
+#define InvMem	    0x80000000
 
-#define Reg	(Reg8|Reg16|Reg32)	/* gen'l register */
-#define WordReg (Reg16|Reg32)
+#define Reg	(Reg8|Reg16|Reg32|Reg64) /* gen'l register */
+#define WordReg (Reg16|Reg32|Reg64)
 #define ImplicitRegister (InOutPortReg|ShiftCount|Acc|FloatAcc)
-#define Imm	(Imm8|Imm8S|Imm16|Imm32) /* gen'l immediate */
-#define Disp	(Disp8|Disp16|Disp32)	/* General displacement */
-#define AnyMem	(Disp|BaseIndex|InvMem)	/* General memory */
+#define Imm	(Imm8|Imm8S|Imm16|Imm32S|Imm32|Imm64) /* gen'l immediate */
+#define EncImm	(Imm8|Imm16|Imm32|Imm32S) /* Encodable gen'l immediate */
+#define Disp	(Disp8|Disp16|Disp32|Disp32S|Disp64) /* General displacement */
+#define AnyMem	(Disp8|Disp16|Disp32|Disp32S|BaseIndex|InvMem)	/* General memory */
   /* The following aliases are defined because the opcode table
      carefully specifies the allowed memory types for each instruction.
      At the moment we can only tell a memory reference size by the
@@ -408,6 +431,9 @@ typedef struct
 {
   char *reg_name;
   unsigned int reg_type;
+  unsigned int reg_flags;
+#define RegRex	    0x1  /* Extended register.  */
+#define RegRex64    0x2  /* Extended 8 bit register.  */
   unsigned int reg_num;
 }
 reg_entry;
@@ -428,6 +454,17 @@ typedef struct
 }
 modrm_byte;
 
+/* x86-64 extension prefix.  */
+typedef struct
+  {
+    unsigned int mode64;
+    unsigned int extX;		/* Used to extend modrm reg field.  */
+    unsigned int extY;		/* Used to extend SIB index field.  */
+    unsigned int extZ;		/* Used to extend modrm reg/mem, SIB base, modrm base fields.  */
+    unsigned int empty;		/* Used to old-style byte registers to new style.  */
+  }
+rex_byte;
+
 /* 386 opcode byte to code indirect addressing.  */
 typedef struct
 {