Opcodes and assembler support for Nios II R2

2015-07-01  Sandra Loosemore  <sandra@codesourcery.com>
	    Cesar Philippidis  <cesar@codesourcery.com>

	gas/
	* config/tc-nios2.c (nios2_min_align): New.
	(nop): Replace with....
	(nop_r1, nop_r2, nop_r2_cdx, nop32, nop16): New.
	(nios2_align): Handle alignment on 2-byte boundaries when CDX
	instructions may be present.
	(s_nios2_align): Adjust reference to nop.
	(CDXBRANCH, IS_CDXBRANCH): New.
	(CDX_UBRANCH_SUBTYPE, CDX_CBRANCH_SUBTYPE): New.
	(nios2_relax_subtype_size): Handle 2-byte CDX branches.
	(nios2_relax_frag): Likewise.
	(md_convert_frag): Handle R2 encodings.
	(nios2_check_overflow): Check that low-order bits are zero
	before applying rightshift from howto.
	(nios2_check_overflow): Correct negative overflow calculation.
	(nios2_diagnose_overflow): Handle signed_immed12_overflow.  Issue
	generic overflow messages for miscellaneous instruction formats.
	(md_apply_fix): Recognize new R2 relocations.  For pc_relative
	relocations, store fixup in *valP.
	(nios2_reglist_mask, nios2_reglist_dir): New.
	(nios2_parse_reglist): New.
	(nios2_parse_base_register): New.
	(nios2_assemble_expression): Handle constant expressions designated
	by BFD_RELOC_NONE.
	(nios2_assemble_reg3): New.
	(nios2_assemble_arg_c): Handle R2 instruction formats.
	(nios2_assemble_arg_d): Likewise.
	(nios2_assemble_arg_s): Likewise.
	(nios2_assemble_arg_t): Likewise.
	(nios2_assemble_arg_D): New.
	(nios2_assemble_arg_S): New.
	(nios2_assemble_arg_T): New.
	(nios2_assemble_arg_i): Handle R2 instruction formats.
	(nios2_assemble_arg_I): New.
	(nios2_assemble_arg_u): Handle R2 instruction formats.
	(nios2_assemble_arg_U): New.
	(nios2_assemble_arg_V): New.
	(nios2_assemble_arg_W): New.
	(nios2_assemble_arg_X): New.
	(nios2_assemble_arg_Y): New.
	(nios2_assemble_arg_o): Handle R2 instruction formats.
	(nios2_assemble_arg_O): New.
	(nios2_assemble_arg_P): New.
	(nios2_assemble_arg_j): Handle R2 instruction formats.
	(nios2_assemble_arg_k): New.
	(nios2_assemble_arg_l): Handle R2 instruction formats.
	(nios2_assemble_arg_m): Likewise.
	(nios2_assemble_arg_M): New.
	(nios2_assemble_arg_N): New.
	(nios2_assemble_arg_e): New.
	(nios2_assemble_arg_f): New.
	(nios2_assemble_arg_g): New.
	(nios2_assemble_arg_h): New.
	(nios2_assemble_arg_R): New.
	(nios2_assemble_arg_B): New.
	(nios2_assemble_args): Handle new argument letters.
	(nios2_consume_arg): Likewise.
	(nios2_translate_pseudo_insn): Avoid dereferencing null pointer
	in error message.
	(nios2_ps_insn_info_structs): Add nop.n.
	(output_ubranch): Handle CDX branches.
	(output_cbranch): Likewise.
	(output_call): Handle R2 encodings.
	(output_movia): Likewise.
	(md_begin): Initialize nios2_min_align.
	(md_assemble): Align to nios2_min_align.  Adjust nios2_min_align
	if a 16-bit instruction is seen.
	(nios2_cons_align): Use appropriate nop pattern.

	include/opcode/
	* nios2.h (enum iw_format_type): Add R2 formats.
	(enum overflow_type): Add signed_immed12_overflow and
	enumeration_overflow for R2.
	(struct nios2_opcode): Document new argument letters for R2.
	(REG_3BIT, REG_LDWM, REG_POP): Define.
	(includes): Include nios2r2.h.
	(nios2_r2_opcodes, nios2_num_r2_opcodes): Declare.
	(nios2_r2_asi_n_mappings, nios2_num_r2_asi_n_mappings): Declare.
	(nios2_r2_shi_n_mappings, nios2_num_r2_shi_n_mappings): Declare.
	(nios2_r2_andi_n_mappings, nios2_num_r2_andi_n_mappings): Declare.
	(nios2_r2_reg3_mappings, nios2_num_r2_reg3_mappings): Declare.
	(nios2_r2_reg_range_mappings, nios2_num_r2_reg_range_mappings):
	Declare.
	* nios2r2.h: New file.

	opcodes/
	* nios2-dis.c (nios2_extract_opcode): New.
	(nios2_disassembler_state): New.
	(nios2_find_opcode_hash): Use mach parameter to select correct
	disassembler state.
	(nios2_print_insn_arg): Extend to support new R2 argument letters
	and formats.
	(print_insn_nios2): Check for 16-bit instruction at end of memory.
	* nios2-opc.c (nios2_builtin_regs): Add R2 register attributes.
	(NIOS2_NUM_OPCODES): Rename to...
	(NIOS2_NUM_R1_OPCODES): This.
	(nios2_r2_opcodes): New.
	(NIOS2_NUM_R2_OPCODES): New.
	(nios2_num_r2_opcodes): New.
	(nios2_r2_asi_n_mappings, nios2_num_r2_asi_n_mappings): New.
	(nios2_r2_shi_n_mappings, nios2_num_r2_shi_n_mappings): New.
	(nios2_r2_andi_n_mappings, nios2_num_r2_andi_n_mappings): New.
	(nios2_r2_reg3_mappings, nios2_num_r2_reg3_mappings): New.
	(nios2_r2_reg_range_mappings, nios2_num_r2_reg_range_mappings):	New.

3 files changed, 952 insertions, 56 deletions

diff --git a/opcodes/ChangeLog b/opcodes/ChangeLog
index 138536a..a3fbc43 100644
--- a/opcodes/ChangeLog
+++ b/opcodes/ChangeLog
@@ -1,3 +1,25 @@
+2015-07-01  Sandra Loosemore  <sandra@codesourcery.com>
+	    Cesar Philippidis  <cesar@codesourcery.com>
+
+	* nios2-dis.c (nios2_extract_opcode): New.
+	(nios2_disassembler_state): New.
+	(nios2_find_opcode_hash): Use mach parameter to select correct
+	disassembler state.
+	(nios2_print_insn_arg): Extend to support new R2 argument letters
+	and formats.
+	(print_insn_nios2): Check for 16-bit instruction at end of memory.
+	* nios2-opc.c (nios2_builtin_regs): Add R2 register attributes.
+	(NIOS2_NUM_OPCODES): Rename to...
+	(NIOS2_NUM_R1_OPCODES): This.
+	(nios2_r2_opcodes): New.
+	(NIOS2_NUM_R2_OPCODES): New.
+	(nios2_num_r2_opcodes): New.
+	(nios2_r2_asi_n_mappings, nios2_num_r2_asi_n_mappings): New.
+	(nios2_r2_shi_n_mappings, nios2_num_r2_shi_n_mappings): New.
+	(nios2_r2_andi_n_mappings, nios2_num_r2_andi_n_mappings): New.
+	(nios2_r2_reg3_mappings, nios2_num_r2_reg3_mappings): New.
+	(nios2_r2_reg_range_mappings, nios2_num_r2_reg_range_mappings):	New.
+
 2015-06-30  Amit Pawar  <Amit.Pawar@amd.com>
 
 	* i386-dis.c (OP_Mwaitx): New.
diff --git a/opcodes/nios2-dis.c b/opcodes/nios2-dis.c
index 80951f1..2735aad 100644
--- a/opcodes/nios2-dis.c
+++ b/opcodes/nios2-dis.c
@@ -55,7 +55,14 @@ nios2_r1_extract_opcode (unsigned int x)
   return GET_IW_R1_OP (x);
 }
 
-/* Pseudo-ops are stored in a different table than regular instructions.  */
+static unsigned int
+nios2_r2_extract_opcode (unsigned int x)
+{
+  return GET_IW_R2_OP (x);
+}
+
+/* We maintain separate hash tables for R1 and R2 opcodes, and pseudo-ops
+   are stored in a different table than regular instructions.  */
 
 typedef struct _nios2_disassembler_state
 {
@@ -79,6 +86,17 @@ nios2_r1_disassembler_state = {
   0
 };
 
+static nios2_disassembler_state
+nios2_r2_disassembler_state = {
+  nios2_r2_opcodes,
+  &nios2_num_r2_opcodes,
+  nios2_r2_extract_opcode,
+  {},
+  {},
+  NULL,
+  0
+};
+  
 /* Function to initialize the opcode hash table.  */
 static void
 nios2_init_opcode_hash (nios2_disassembler_state *state)
@@ -155,13 +173,17 @@ nios2_init_opcode_hash (nios2_disassembler_state *state)
 /* Return a pointer to an nios2_opcode struct for a given instruction
    word OPCODE for bfd machine MACH, or NULL if there is an error.  */
 const struct nios2_opcode *
-nios2_find_opcode_hash (unsigned long opcode,
-			unsigned long mach ATTRIBUTE_UNUSED)
+nios2_find_opcode_hash (unsigned long opcode, unsigned long mach)
 {
   nios2_opcode_hash *entry;
   nios2_disassembler_state *state;
 
-  state = &nios2_r1_disassembler_state;
+  /* Select the right instruction set, hash tables, and opcode accessor
+     for the mach variant.  */
+  if (mach == bfd_mach_nios2r2)
+    state = &nios2_r2_disassembler_state;
+  else
+    state = &nios2_r1_disassembler_state;
 
   /* Build a hash table to shorten the search time.  */
   if (!state->init)
@@ -260,19 +282,46 @@ nios2_print_insn_arg (const char *argptr,
       (*info->fprintf_func) (info->stream, "%c", *argptr);
       break;
 
+    case 'c':
+      /* Control register index.  */
+      switch (op->format)
+	{
+	case iw_r_type:
+	  i = GET_IW_R_IMM5 (opcode);
+	  break;
+	case iw_F3X6L5_type:
+	  i = GET_IW_F3X6L5_IMM5 (opcode);
+	  break;
+	default:
+	  bad_opcode (op);
+	}
+      reg_base = nios2_control_regs ();
+      (*info->fprintf_func) (info->stream, "%s", reg_base[i].name);
+      break;
+
     case 'd':
+      reg_base = nios2_regs;
       switch (op->format)
 	{
 	case iw_r_type:
 	  i = GET_IW_R_C (opcode);
-	  reg_base = nios2_regs;
 	  break;
 	case iw_custom_type:
 	  i = GET_IW_CUSTOM_C (opcode);
 	  if (GET_IW_CUSTOM_READC (opcode) == 0)
 	    reg_base = nios2_coprocessor_regs ();
-	  else
-	    reg_base = nios2_regs;
+	  break;
+	case iw_F3X6L5_type:
+	case iw_F3X6_type:
+	  i = GET_IW_F3X6L5_C (opcode);
+	  break;
+	case iw_F3X8_type:
+	  i = GET_IW_F3X8_C (opcode);
+	  if (GET_IW_F3X8_READC (opcode) == 0)
+	    reg_base = nios2_coprocessor_regs ();
+	  break;
+	case iw_F2_type:
+	  i = GET_IW_F2_B (opcode);
 	  break;
 	default:
 	  bad_opcode (op);
@@ -284,22 +333,52 @@ nios2_print_insn_arg (const char *argptr,
       break;
 
     case 's':
+      reg_base = nios2_regs;
       switch (op->format)
 	{
 	case iw_r_type:
 	  i = GET_IW_R_A (opcode);
-	  reg_base = nios2_regs;
 	  break;
 	case iw_i_type:
 	  i = GET_IW_I_A (opcode);
-	  reg_base = nios2_regs;
 	  break;
 	case iw_custom_type:
 	  i = GET_IW_CUSTOM_A (opcode);
 	  if (GET_IW_CUSTOM_READA (opcode) == 0)
 	    reg_base = nios2_coprocessor_regs ();
-	  else
-	    reg_base = nios2_regs;
+	  break;
+	case iw_F2I16_type:
+	  i = GET_IW_F2I16_A (opcode);
+	  break;
+	case iw_F2X4I12_type:
+	  i = GET_IW_F2X4I12_A (opcode);
+	  break;
+	case iw_F1X4I12_type:
+	  i = GET_IW_F1X4I12_A (opcode);
+	  break;
+	case iw_F1X4L17_type:
+	  i = GET_IW_F1X4L17_A (opcode);
+	  break;
+	case iw_F3X6L5_type:
+	case iw_F3X6_type:
+	  i = GET_IW_F3X6L5_A (opcode);
+	  break;
+	case iw_F2X6L10_type:
+	  i = GET_IW_F2X6L10_A (opcode);
+	  break;
+	case iw_F3X8_type:
+	  i = GET_IW_F3X8_A (opcode);
+	  if (GET_IW_F3X8_READA (opcode) == 0)
+	    reg_base = nios2_coprocessor_regs ();
+	  break;
+	case iw_F1X1_type:
+	  i = GET_IW_F1X1_A (opcode);
+	  break;
+	case iw_F1I5_type:
+	  i = 27;   /* Implicit stack pointer reference.  */
+	  break;
+	case iw_F2_type:
+	  i = GET_IW_F2_A (opcode);
 	  break;
 	default:
 	  bad_opcode (op);
@@ -311,22 +390,46 @@ nios2_print_insn_arg (const char *argptr,
       break;
 
     case 't':
+      reg_base = nios2_regs;
       switch (op->format)
 	{
 	case iw_r_type:
 	  i = GET_IW_R_B (opcode);
-	  reg_base = nios2_regs;
 	  break;
 	case iw_i_type:
 	  i = GET_IW_I_B (opcode);
-	  reg_base = nios2_regs;
 	  break;
 	case iw_custom_type:
 	  i = GET_IW_CUSTOM_B (opcode);
 	  if (GET_IW_CUSTOM_READB (opcode) == 0)
 	    reg_base = nios2_coprocessor_regs ();
-	  else
-	    reg_base = nios2_regs;
+	  break;
+	case iw_F2I16_type:
+	  i = GET_IW_F2I16_B (opcode);
+	  break;
+	case iw_F2X4I12_type:
+	  i = GET_IW_F2X4I12_B (opcode);
+	  break;
+	case iw_F3X6L5_type:
+	case iw_F3X6_type:
+	  i = GET_IW_F3X6L5_B (opcode);
+	  break;
+	case iw_F2X6L10_type:
+	  i = GET_IW_F2X6L10_B (opcode);
+	  break;
+	case iw_F3X8_type:
+	  i = GET_IW_F3X8_B (opcode);
+	  if (GET_IW_F3X8_READB (opcode) == 0)
+	    reg_base = nios2_coprocessor_regs ();
+	  break;
+	case iw_F1I5_type:
+	  i = GET_IW_F1I5_B (opcode);
+	  break;
+	case iw_F2_type:
+	  i = GET_IW_F2_B (opcode);
+	  break;
+	case iw_T1X1I6_type:
+	  i = 0;
 	  break;
 	default:
 	  bad_opcode (op);
@@ -337,6 +440,110 @@ nios2_print_insn_arg (const char *argptr,
 	(*info->fprintf_func) (info->stream, "unknown");
       break;
 
+    case 'D':
+      switch (op->format)
+	{
+	case iw_T1I7_type:
+	  i = GET_IW_T1I7_A3 (opcode);
+	  break;
+	case iw_T2X1L3_type:
+	  i = GET_IW_T2X1L3_B3 (opcode);
+	  break;
+	case iw_T2X1I3_type:
+	  i = GET_IW_T2X1I3_B3 (opcode);
+	  break;
+	case iw_T3X1_type:
+	  i = GET_IW_T3X1_C3 (opcode);
+	  break;
+	case iw_T2X3_type:
+	  if (op->num_args == 3)
+	    i = GET_IW_T2X3_A3 (opcode);
+	  else
+	    i = GET_IW_T2X3_B3 (opcode);
+	  break;
+	default:
+	  bad_opcode (op);
+	}
+      i = nios2_r2_reg3_mappings[i];
+      (*info->fprintf_func) (info->stream, "%s", nios2_regs[i].name);
+      break;
+
+    case 'M':
+      /* 6-bit unsigned immediate with no shift.  */
+      switch (op->format)
+	{
+	case iw_T1X1I6_type:
+	  i = GET_IW_T1X1I6_IMM6 (opcode);
+	  break;
+	default:
+	  bad_opcode (op);
+	}
+      (*info->fprintf_func) (info->stream, "%ld", i);
+      break;
+
+    case 'N':
+      /* 6-bit unsigned immediate with 2-bit shift.  */
+      switch (op->format)
+	{
+	case iw_T1X1I6_type:
+	  i = GET_IW_T1X1I6_IMM6 (opcode) << 2;
+	  break;
+	default:
+	  bad_opcode (op);
+	}
+      (*info->fprintf_func) (info->stream, "%ld", i);
+      break;
+
+    case 'S':
+      switch (op->format)
+	{
+	case iw_T1I7_type:
+	  i = GET_IW_T1I7_A3 (opcode);
+	  break;
+	case iw_T2I4_type:
+	  i = GET_IW_T2I4_A3 (opcode);
+	  break;
+	case iw_T2X1L3_type:
+	  i = GET_IW_T2X1L3_A3 (opcode);
+	  break;
+	case iw_T2X1I3_type:
+	  i = GET_IW_T2X1I3_A3 (opcode);
+	  break;
+	case iw_T3X1_type:
+	  i = GET_IW_T3X1_A3 (opcode);
+	  break;
+	case iw_T2X3_type:
+	  i = GET_IW_T2X3_A3 (opcode);
+	  break;
+	case iw_T1X1I6_type:
+	  i = GET_IW_T1X1I6_A3 (opcode);
+	  break;
+	default:
+	  bad_opcode (op);
+	}
+      i = nios2_r2_reg3_mappings[i];
+      (*info->fprintf_func) (info->stream, "%s", nios2_regs[i].name);
+      break;
+
+    case 'T':
+      switch (op->format)
+	{
+	case iw_T2I4_type:
+	  i = GET_IW_T2I4_B3 (opcode);
+	  break;
+	case iw_T3X1_type:
+	  i = GET_IW_T3X1_B3 (opcode);
+	  break;
+	case iw_T2X3_type:
+	  i = GET_IW_T2X3_B3 (opcode);
+	  break;
+	default:
+	  bad_opcode (op);
+	}
+      i = nios2_r2_reg3_mappings[i];
+      (*info->fprintf_func) (info->stream, "%s", nios2_regs[i].name);
+      break;
+
     case 'i':
       /* 16-bit signed immediate.  */
       switch (op->format)
@@ -344,6 +551,25 @@ nios2_print_insn_arg (const char *argptr,
 	case iw_i_type:
 	  i = (signed) (GET_IW_I_IMM16 (opcode) << 16) >> 16;
 	  break;
+	case iw_F2I16_type:
+	  i = (signed) (GET_IW_F2I16_IMM16 (opcode) << 16) >> 16;
+	  break;
+	default:
+	  bad_opcode (op);
+	}
+      (*info->fprintf_func) (info->stream, "%ld", i);
+      break;
+
+    case 'I':
+      /* 12-bit signed immediate.  */
+      switch (op->format)
+	{
+	case iw_F2X4I12_type:
+	  i = (signed) (GET_IW_F2X4I12_IMM12 (opcode) << 20) >> 20;
+	  break;
+	case iw_F1X4I12_type:
+	  i = (signed) (GET_IW_F1X4I12_IMM12 (opcode) << 20) >> 20;
+	  break;
 	default:
 	  bad_opcode (op);
 	}
@@ -357,6 +583,80 @@ nios2_print_insn_arg (const char *argptr,
 	case iw_i_type:
 	  i = GET_IW_I_IMM16 (opcode);
 	  break;
+	case iw_F2I16_type:
+	  i = GET_IW_F2I16_IMM16 (opcode);
+	  break;
+	default:
+	  bad_opcode (op);
+	}
+      (*info->fprintf_func) (info->stream, "%ld", i);
+      break;
+
+    case 'U':
+      /* 7-bit unsigned immediate with 2-bit shift.  */
+      switch (op->format)
+	{
+	case iw_T1I7_type:
+	  i = GET_IW_T1I7_IMM7 (opcode) << 2;
+	  break;
+	case iw_X1I7_type:
+	  i = GET_IW_X1I7_IMM7 (opcode) << 2;
+	  break;
+	default:
+	  bad_opcode (op);
+	}
+      (*info->fprintf_func) (info->stream, "%ld", i);
+      break;
+
+    case 'V':
+      /* 5-bit unsigned immediate with 2-bit shift.  */
+      switch (op->format)
+	{
+	case iw_F1I5_type:
+	  i = GET_IW_F1I5_IMM5 (opcode) << 2;
+	  break;
+	default:
+	  bad_opcode (op);
+	}
+      (*info->fprintf_func) (info->stream, "%ld", i);
+      break;
+
+    case 'W':
+      /* 4-bit unsigned immediate with 2-bit shift.  */
+      switch (op->format)
+	{
+	case iw_T2I4_type:
+	  i = GET_IW_T2I4_IMM4 (opcode) << 2;
+	  break;
+	case iw_L5I4X1_type:
+	  i = GET_IW_L5I4X1_IMM4 (opcode) << 2;
+	  break;
+	default:
+	  bad_opcode (op);
+	}
+      (*info->fprintf_func) (info->stream, "%ld", i);
+      break;
+
+    case 'X':
+      /* 4-bit unsigned immediate with 1-bit shift.  */
+      switch (op->format)
+	{
+	case iw_T2I4_type:
+	  i = GET_IW_T2I4_IMM4 (opcode) << 1;
+	  break;
+	default:
+	  bad_opcode (op);
+	}
+      (*info->fprintf_func) (info->stream, "%ld", i);
+      break;
+
+    case 'Y':
+      /* 4-bit unsigned immediate without shift.  */
+      switch (op->format)
+	{
+	case iw_T2I4_type:
+	  i = GET_IW_T2I4_IMM4 (opcode);
+	  break;
 	default:
 	  bad_opcode (op);
 	}
@@ -370,6 +670,9 @@ nios2_print_insn_arg (const char *argptr,
 	case iw_i_type:
 	  i = (signed) (GET_IW_I_IMM16 (opcode) << 16) >> 16;
 	  break;
+	case iw_F2I16_type:
+	  i = (signed) (GET_IW_F2I16_IMM16 (opcode) << 16) >> 16;
+	  break;
 	default:
 	  bad_opcode (op);
 	}
@@ -377,6 +680,34 @@ nios2_print_insn_arg (const char *argptr,
       (*info->print_address_func) (address, info);
       break;
 
+    case 'O':
+      /* 10-bit signed address offset with 1-bit shift.  */
+      switch (op->format)
+	{
+	case iw_I10_type:
+	  i = (signed) (GET_IW_I10_IMM10 (opcode) << 22) >> 21;
+	  break;
+	default:
+	  bad_opcode (op);
+	}
+      address = address + 2 + i;
+      (*info->print_address_func) (address, info);
+      break;
+
+    case 'P':
+      /* 7-bit signed address offset with 1-bit shift.  */
+      switch (op->format)
+	{
+	case iw_T1I7_type:
+	  i = (signed) (GET_IW_T1I7_IMM7 (opcode) << 25) >> 24;
+	  break;
+	default:
+	  bad_opcode (op);
+	}
+      address = address + 2 + i;
+      (*info->print_address_func) (address, info);
+      break;
+
     case 'j':
       /* 5-bit unsigned immediate.  */
       switch (op->format)
@@ -384,6 +715,28 @@ nios2_print_insn_arg (const char *argptr,
 	case iw_r_type:
 	  i = GET_IW_R_IMM5 (opcode);
 	  break;
+	case iw_F3X6L5_type:
+	  i = GET_IW_F3X6L5_IMM5 (opcode);
+	  break;
+	case iw_F2X6L10_type:
+	  i = GET_IW_F2X6L10_MSB (opcode);
+	  break;
+	case iw_X2L5_type:
+	  i = GET_IW_X2L5_IMM5 (opcode);
+	  break;
+	default:
+	  bad_opcode (op);
+	}
+      (*info->fprintf_func) (info->stream, "%ld", i);
+      break;
+
+    case 'k':
+      /* Second 5-bit unsigned immediate field.  */
+      switch (op->format)
+	{
+	case iw_F2X6L10_type:
+	  i = GET_IW_F2X6L10_LSB (opcode);
+	  break;
 	default:
 	  bad_opcode (op);
 	}
@@ -397,6 +750,9 @@ nios2_print_insn_arg (const char *argptr,
 	case iw_custom_type:
 	  i = GET_IW_CUSTOM_N (opcode);
 	  break;
+	case iw_F3X8_type:
+	  i = GET_IW_F3X8_N (opcode);
+	  break;
 	default:
 	  bad_opcode (op);
 	}
@@ -410,6 +766,9 @@ nios2_print_insn_arg (const char *argptr,
 	case iw_j_type:
 	  i = GET_IW_J_IMM26 (opcode);
 	  break;
+	case iw_L26_type:
+	  i = GET_IW_L26_IMM26 (opcode);
+	  break;
 	default:
 	  bad_opcode (op);
 	}
@@ -419,18 +778,144 @@ nios2_print_insn_arg (const char *argptr,
       (*info->print_address_func) (address, info);
       break;
 
-    case 'c':
-      /* Control register index.  */
+    case 'e':
+      /* Encoded enumeration for addi.n/subi.n.  */
       switch (op->format)
 	{
-	case iw_r_type:
-	  i = GET_IW_R_IMM5 (opcode);
+	case iw_T2X1I3_type:
+	  i = nios2_r2_asi_n_mappings[GET_IW_T2X1I3_IMM3 (opcode)];
+	  break;
+	default:
+	  bad_opcode (op);
+	}
+      (*info->fprintf_func) (info->stream, "%lu", i);
+      break;
+
+    case 'f':
+      /* Encoded enumeration for slli.n/srli.n.  */
+      switch (op->format)
+	{
+	case iw_T2X1L3_type:
+	  i = nios2_r2_shi_n_mappings[GET_IW_T2X1I3_IMM3 (opcode)];
+	  break;
+	default:
+	  bad_opcode (op);
+	}
+      (*info->fprintf_func) (info->stream, "%lu", i);
+      break;
+
+    case 'g':
+      /* Encoded enumeration for andi.n.  */
+      switch (op->format)
+	{
+	case iw_T2I4_type:
+	  i = nios2_r2_andi_n_mappings[GET_IW_T2I4_IMM4 (opcode)];
+	  break;
+	default:
+	  bad_opcode (op);
+	}
+      (*info->fprintf_func) (info->stream, "%lu", i);
+      break;
+
+    case 'h':
+      /* Encoded enumeration for movi.n.  */
+      switch (op->format)
+	{
+	case iw_T1I7_type:
+	  i = GET_IW_T1I7_IMM7 (opcode);
+	  if (i == 125)
+	    i = 0xff;
+	  else if (i == 126)
+	    i = -2;
+	  else if (i == 127)
+	    i = -1;
+	  break;
+	default:
+	  bad_opcode (op);
+	}
+      (*info->fprintf_func) (info->stream, "%ld", i);
+      break;
+
+    case 'R':
+      {
+	unsigned long reglist = 0;
+	int dir = 1;
+	int k, t;
+
+	switch (op->format)
+	  {
+	  case iw_F1X4L17_type:
+	    /* Encoding for ldwm/stwm.  */
+	    i = GET_IW_F1X4L17_REGMASK (opcode);
+	    if (GET_IW_F1X4L17_RS (opcode))
+	      {
+		reglist = ((i << 14) & 0x00ffc000);
+		if (i & (1 << 10))
+		  reglist |= (1 << 28);
+		if (i & (1 << 11))
+		  reglist |= (1 << 31);
+	      }
+	    else
+	      reglist = i << 2;
+	    dir = GET_IW_F1X4L17_REGMASK (opcode) ? 1 : -1;
+	    break;
+	    
+	  case iw_L5I4X1_type:
+	    /* Encoding for push.n/pop.n.  */
+	    reglist |= (1 << 31);
+	    if (GET_IW_L5I4X1_FP (opcode))
+	      reglist |= (1 << 28);
+	    if (GET_IW_L5I4X1_CS (opcode))
+	      {
+		int val = GET_IW_L5I4X1_REGRANGE (opcode);
+		reglist |= nios2_r2_reg_range_mappings[val];
+	      }
+	    dir = (op->match == MATCH_R2_POP_N ? 1 : -1);
+	    break;
+
+	  default:
+	    bad_opcode (op);
+	  }
+
+	t = 0;
+	(*info->fprintf_func) (info->stream, "{");
+	for (k = (dir == 1 ? 0 : 31);
+	     (dir == 1 && k < 32) || (dir == -1 && k >= 0);
+	     k += dir)
+	  if (reglist & (1 << k))
+	    {
+	      if (t)
+		(*info->fprintf_func) (info->stream, ",");
+	      else
+		t++;
+	      (*info->fprintf_func) (info->stream, "%s", nios2_regs[k].name);
+	    }
+	(*info->fprintf_func) (info->stream, "}");
+	break;
+      }
+
+    case 'B':
+      /* Base register and options for ldwm/stwm.  */
+      switch (op->format)
+	{
+	case iw_F1X4L17_type:
+	  if (GET_IW_F1X4L17_ID (opcode) == 0)
+	    (*info->fprintf_func) (info->stream, "--");
+
+	  i = GET_IW_F1X4I12_A (opcode);
+	  (*info->fprintf_func) (info->stream, "(%s)", 
+				 nios2_builtin_regs[i].name);
+
+	  if (GET_IW_F1X4L17_ID (opcode))
+	    (*info->fprintf_func) (info->stream, "++");
+	  if (GET_IW_F1X4L17_WB (opcode))
+	    (*info->fprintf_func) (info->stream, ",writeback");
+	  if (GET_IW_F1X4L17_PC (opcode))
+	    (*info->fprintf_func) (info->stream, ",ret");
 	  break;
 	default:
 	  bad_opcode (op);
 	}
-      reg_base = nios2_control_regs ();
-      (*info->fprintf_func) (info->stream, "%s", reg_base[i].name);
       break;
 
     default:
@@ -512,14 +997,27 @@ print_insn_nios2 (bfd_vma address, disassemble_info *info,
 	insn = (unsigned long) bfd_getb32 (buffer);
       else
 	insn = (unsigned long) bfd_getl32 (buffer);
-      status = nios2_disassemble (address, insn, info);
+      return nios2_disassemble (address, insn, info);
     }
-  else
+
+  /* We might have a 16-bit R2 instruction at the end of memory.  Try that.  */
+  if (info->mach == bfd_mach_nios2r2)
     {
-      (*info->memory_error_func) (status, address, info);
-      status = -1;
+      status = (*info->read_memory_func) (address, buffer, 2, info);
+      if (status == 0)
+	{
+	  unsigned long insn;
+	  if (endianness == BFD_ENDIAN_BIG)
+	    insn = (unsigned long) bfd_getb16 (buffer);
+	  else
+	    insn = (unsigned long) bfd_getl16 (buffer);
+	  return nios2_disassemble (address, insn, info);
+	}
     }
-  return status;
+
+  /* If we got here, we couldn't read anything.  */
+  (*info->memory_error_func) (status, address, info);
+  return -1;
 }
 
 /* These two functions are the main entry points, accessed from
diff --git a/opcodes/nios2-opc.c b/opcodes/nios2-opc.c
index d5ec06f..d119f9a 100644
--- a/opcodes/nios2-opc.c
+++ b/opcodes/nios2-opc.c
@@ -30,36 +30,36 @@ const struct nios2_reg nios2_builtin_regs[] = {
   /* Standard register names.  */
   {"zero", 0, REG_NORMAL},
   {"at", 1, REG_NORMAL},			/* assembler temporary */
-  {"r2", 2, REG_NORMAL},
-  {"r3", 3, REG_NORMAL},
-  {"r4", 4, REG_NORMAL},
-  {"r5", 5, REG_NORMAL},
-  {"r6", 6, REG_NORMAL},
-  {"r7", 7, REG_NORMAL},
-  {"r8", 8, REG_NORMAL},
-  {"r9", 9, REG_NORMAL},
-  {"r10", 10, REG_NORMAL},
-  {"r11", 11, REG_NORMAL},
-  {"r12", 12, REG_NORMAL},
-  {"r13", 13, REG_NORMAL},
-  {"r14", 14, REG_NORMAL},
-  {"r15", 15, REG_NORMAL},
-  {"r16", 16, REG_NORMAL},
-  {"r17", 17, REG_NORMAL},
-  {"r18", 18, REG_NORMAL},
-  {"r19", 19, REG_NORMAL},
-  {"r20", 20, REG_NORMAL},
-  {"r21", 21, REG_NORMAL},
-  {"r22", 22, REG_NORMAL},
-  {"r23", 23, REG_NORMAL},
+  {"r2", 2, REG_NORMAL | REG_3BIT | REG_LDWM},
+  {"r3", 3, REG_NORMAL | REG_3BIT | REG_LDWM},
+  {"r4", 4, REG_NORMAL | REG_3BIT | REG_LDWM},
+  {"r5", 5, REG_NORMAL | REG_3BIT | REG_LDWM},
+  {"r6", 6, REG_NORMAL | REG_3BIT | REG_LDWM},
+  {"r7", 7, REG_NORMAL | REG_3BIT | REG_LDWM},
+  {"r8", 8, REG_NORMAL | REG_LDWM},
+  {"r9", 9, REG_NORMAL | REG_LDWM},
+  {"r10", 10, REG_NORMAL | REG_LDWM},
+  {"r11", 11, REG_NORMAL | REG_LDWM},
+  {"r12", 12, REG_NORMAL | REG_LDWM},
+  {"r13", 13, REG_NORMAL | REG_LDWM},
+  {"r14", 14, REG_NORMAL | REG_LDWM},
+  {"r15", 15, REG_NORMAL | REG_LDWM},
+  {"r16", 16, REG_NORMAL | REG_3BIT | REG_LDWM | REG_POP},
+  {"r17", 17, REG_NORMAL | REG_3BIT | REG_LDWM | REG_POP},
+  {"r18", 18, REG_NORMAL | REG_LDWM | REG_POP},
+  {"r19", 19, REG_NORMAL | REG_LDWM | REG_POP},
+  {"r20", 20, REG_NORMAL | REG_LDWM | REG_POP},
+  {"r21", 21, REG_NORMAL | REG_LDWM | REG_POP},
+  {"r22", 22, REG_NORMAL | REG_LDWM | REG_POP},
+  {"r23", 23, REG_NORMAL | REG_LDWM | REG_POP},
   {"et", 24, REG_NORMAL},
   {"bt", 25, REG_NORMAL},
   {"gp", 26, REG_NORMAL},			/* global pointer */
   {"sp", 27, REG_NORMAL},			/* stack pointer */
-  {"fp", 28, REG_NORMAL},			/* frame pointer */
+  {"fp", 28, REG_NORMAL | REG_LDWM | REG_POP},	/* frame pointer */
   {"ea", 29, REG_NORMAL},			/* exception return address */
   {"sstatus", 30, REG_NORMAL},			/* saved processor status */
-  {"ra", 31, REG_NORMAL},			/* return address */
+  {"ra", 31, REG_NORMAL | REG_LDWM | REG_POP},	/* return address */
 
   /* Alternative names for special registers.  */
   {"r0", 0, REG_NORMAL},
@@ -68,11 +68,11 @@ const struct nios2_reg nios2_builtin_regs[] = {
   {"r25", 25, REG_NORMAL},
   {"r26", 26, REG_NORMAL},
   {"r27", 27, REG_NORMAL},
-  {"r28", 28, REG_NORMAL},
+  {"r28", 28, REG_NORMAL | REG_LDWM | REG_POP},
   {"r29", 29, REG_NORMAL},
   {"r30", 30, REG_NORMAL},
   {"ba", 30, REG_NORMAL},			/* breakpoint return address */
-  {"r31", 31, REG_NORMAL},
+  {"r31", 31, REG_NORMAL | REG_LDWM | REG_POP},
 
   /* Control register names.  */
   {"status", 0, REG_CONTROL},
@@ -398,10 +398,386 @@ const struct nios2_opcode nios2_r1_opcodes[] =
    MATCH_R1_XORI, MASK_R1_XORI, 0, unsigned_immed16_overflow}
 };
 
-#define NIOS2_NUM_OPCODES \
+#define NIOS2_NUM_R1_OPCODES \
        ((sizeof nios2_r1_opcodes) / (sizeof (nios2_r1_opcodes[0])))
-const int nios2_num_r1_opcodes = NIOS2_NUM_OPCODES;
+const int nios2_num_r1_opcodes = NIOS2_NUM_R1_OPCODES;
 
+
+const struct nios2_opcode nios2_r2_opcodes[] =
+{
+  /* { name, args, args_test, num_args, size, format,
+       match, mask, pinfo, overflow } */
+  {"add", "d,s,t", "d,s,t,E", 3, 4, iw_F3X6_type,
+   MATCH_R2_ADD, MASK_R2_ADD, 0, no_overflow},
+  {"addi", "t,s,i", "t,s,i,E", 3, 4, iw_F2I16_type,
+   MATCH_R2_ADDI, MASK_R2_ADDI, 0, signed_immed16_overflow},
+  {"add.n", "D,S,T", "D,S,T,E", 3, 2, iw_T3X1_type,
+   MATCH_R2_ADD_N, MASK_R2_ADD_N, 0, no_overflow},
+  {"addi.n", "D,S,e", "D,S,e,E", 3, 2, iw_T2X1I3_type,
+   MATCH_R2_ADDI_N, MASK_R2_ADDI_N, 0, enumeration_overflow},
+  {"and", "d,s,t", "d,s,t,E", 3, 4, iw_F3X6_type,
+   MATCH_R2_AND, MASK_R2_AND, 0, no_overflow},
+  {"andchi", "t,s,u", "t,s,u,E", 3, 4, iw_F2I16_type,
+   MATCH_R2_ANDCHI, MASK_R2_ANDCHI, 0, unsigned_immed16_overflow},
+  {"andci", "t,s,u", "t,s,u,E", 3, 4, iw_F2I16_type,
+   MATCH_R2_ANDCI, MASK_R2_ANDCI, 0, unsigned_immed16_overflow},
+  {"andhi", "t,s,u", "t,s,u,E", 3, 4, iw_F2I16_type,
+   MATCH_R2_ANDHI, MASK_R2_ANDHI, 0, unsigned_immed16_overflow},
+  {"andi", "t,s,u", "t,s,u,E", 3, 4, iw_F2I16_type,
+   MATCH_R2_ANDI, MASK_R2_ANDI, 0, unsigned_immed16_overflow},
+  {"andi.n", "T,S,g", "T,S,g,E", 3, 2, iw_T2I4_type,
+   MATCH_R2_ANDI_N, MASK_R2_ANDI_N, 0, enumeration_overflow},
+  {"and.n", "D,S,T", "D,S,T,E", 3, 2, iw_T2X3_type,
+   MATCH_R2_AND_N, MASK_R2_AND_N, 0, no_overflow},
+  {"beq", "s,t,o", "s,t,o,E", 3, 4, iw_F2I16_type,
+   MATCH_R2_BEQ, MASK_R2_BEQ, NIOS2_INSN_CBRANCH, branch_target_overflow},
+  {"beqz.n", "S,P", "S,P,E", 2, 2, iw_T1I7_type,
+   MATCH_R2_BEQZ_N, MASK_R2_BEQZ_N, NIOS2_INSN_CBRANCH, branch_target_overflow},
+  {"bge", "s,t,o", "s,t,o,E", 3, 4, iw_F2I16_type,
+   MATCH_R2_BGE, MASK_R2_BGE, NIOS2_INSN_CBRANCH, branch_target_overflow},
+  {"bgeu", "s,t,o", "s,t,o,E", 3, 4, iw_F2I16_type,
+   MATCH_R2_BGEU, MASK_R2_BGEU, NIOS2_INSN_CBRANCH, branch_target_overflow},
+  {"bgt", "s,t,o", "s,t,o,E", 3, 4, iw_F2I16_type,
+   MATCH_R2_BGT, MASK_R2_BGT,
+   NIOS2_INSN_MACRO|NIOS2_INSN_CBRANCH, branch_target_overflow},
+  {"bgtu", "s,t,o", "s,t,o,E", 3, 4, iw_F2I16_type,
+   MATCH_R2_BGTU, MASK_R2_BGTU,
+   NIOS2_INSN_MACRO|NIOS2_INSN_CBRANCH, branch_target_overflow},
+  {"ble", "s,t,o", "s,t,o,E", 3, 4, iw_F2I16_type,
+   MATCH_R2_BLE, MASK_R2_BLE,
+   NIOS2_INSN_MACRO|NIOS2_INSN_CBRANCH, branch_target_overflow},
+  {"bleu", "s,t,o", "s,t,o,E", 3, 4, iw_F2I16_type,
+   MATCH_R2_BLEU, MASK_R2_BLEU,
+   NIOS2_INSN_MACRO|NIOS2_INSN_CBRANCH, branch_target_overflow},
+  {"blt", "s,t,o", "s,t,o,E", 3, 4, iw_F2I16_type,
+   MATCH_R2_BLT, MASK_R2_BLT, NIOS2_INSN_CBRANCH, branch_target_overflow},
+  {"bltu", "s,t,o", "s,t,o,E", 3, 4, iw_F2I16_type,
+   MATCH_R2_BLTU, MASK_R2_BLTU, NIOS2_INSN_CBRANCH, branch_target_overflow},
+  {"bne", "s,t,o", "s,t,o,E", 3, 4, iw_F2I16_type,
+   MATCH_R2_BNE, MASK_R2_BNE, NIOS2_INSN_CBRANCH, branch_target_overflow},
+  {"bnez.n", "S,P", "S,P,E", 2, 2, iw_T1I7_type,
+   MATCH_R2_BNEZ_N, MASK_R2_BNEZ_N, NIOS2_INSN_CBRANCH, branch_target_overflow},
+  {"br", "o", "o,E", 1, 4, iw_F2I16_type,
+   MATCH_R2_BR, MASK_R2_BR, NIOS2_INSN_UBRANCH, branch_target_overflow},
+  {"break", "j", "j,E", 1, 4, iw_F3X6L5_type,
+   MATCH_R2_BREAK, MASK_R2_BREAK, NIOS2_INSN_OPTARG, no_overflow},
+  {"break.n", "j", "j,E", 1, 2, iw_X2L5_type,
+   MATCH_R2_BREAK_N, MASK_R2_BREAK_N, NIOS2_INSN_OPTARG, no_overflow},
+  {"bret", "", "E", 0, 4, iw_F3X6_type,
+   MATCH_R2_BRET, MASK_R2_BRET, 0, no_overflow},
+  {"br.n", "O", "O,E", 1, 2, iw_I10_type,
+   MATCH_R2_BR_N, MASK_R2_BR_N, NIOS2_INSN_UBRANCH, branch_target_overflow},
+  {"call", "m", "m,E", 1, 4, iw_L26_type,
+   MATCH_R2_CALL, MASK_R2_CALL, NIOS2_INSN_CALL, call_target_overflow},
+  {"callr", "s", "s,E", 1, 4, iw_F3X6_type,
+   MATCH_R2_CALLR, MASK_R2_CALLR, 0, no_overflow},
+  {"callr.n", "s", "s,E", 1, 2, iw_F1X1_type,
+   MATCH_R2_CALLR_N, MASK_R2_CALLR_N, 0, no_overflow},
+  {"cmpeq", "d,s,t", "d,s,t,E", 3, 4, iw_F3X6_type,
+   MATCH_R2_CMPEQ, MASK_R2_CMPEQ, 0, no_overflow},
+  {"cmpeqi", "t,s,i", "t,s,i,E", 3, 4, iw_F2I16_type,
+   MATCH_R2_CMPEQI, MASK_R2_CMPEQI, 0, signed_immed16_overflow},
+  {"cmpge", "d,s,t", "d,s,t,E", 3, 4, iw_F3X6_type,
+   MATCH_R2_CMPGE, MASK_R2_CMPGE, 0, no_overflow},
+  {"cmpgei", "t,s,i", "t,s,i,E", 3, 4, iw_F2I16_type,
+   MATCH_R2_CMPGEI, MASK_R2_CMPGEI, 0, signed_immed16_overflow},
+  {"cmpgeu", "d,s,t", "d,s,t,E", 3, 4, iw_F3X6_type,
+   MATCH_R2_CMPGEU, MASK_R2_CMPGEU, 0, no_overflow},
+  {"cmpgeui", "t,s,u", "t,s,u,E", 3, 4, iw_F2I16_type,
+   MATCH_R2_CMPGEUI, MASK_R2_CMPGEUI, 0, unsigned_immed16_overflow},
+  {"cmpgt", "d,s,t", "d,s,t,E", 3, 4, iw_F3X6_type,
+   MATCH_R2_CMPGT, MASK_R2_CMPGT, NIOS2_INSN_MACRO, no_overflow},
+  {"cmpgti", "t,s,i", "t,s,i,E", 3, 4, iw_F2I16_type,
+   MATCH_R2_CMPGTI, MASK_R2_CMPGTI, NIOS2_INSN_MACRO, signed_immed16_overflow},
+  {"cmpgtu", "d,s,t", "d,s,t,E", 3, 4, iw_F3X6_type,
+   MATCH_R2_CMPGTU, MASK_R2_CMPGTU, NIOS2_INSN_MACRO, no_overflow},
+  {"cmpgtui", "t,s,u", "t,s,u,E", 3, 4, iw_F2I16_type,
+   MATCH_R2_CMPGTUI, MASK_R2_CMPGTUI,
+   NIOS2_INSN_MACRO, unsigned_immed16_overflow},
+  {"cmple", "d,s,t", "d,s,t,E", 3, 4, iw_F3X6_type,
+   MATCH_R2_CMPLE, MASK_R2_CMPLE, NIOS2_INSN_MACRO, no_overflow},
+  {"cmplei", "t,s,i", "t,s,i,E", 3, 4, iw_F2I16_type,
+   MATCH_R2_CMPLEI, MASK_R2_CMPLEI, NIOS2_INSN_MACRO, signed_immed16_overflow},
+  {"cmpleu", "d,s,t", "d,s,t,E", 3, 4, iw_F3X6_type,
+   MATCH_R2_CMPLEU, MASK_R2_CMPLEU, NIOS2_INSN_MACRO, no_overflow},
+  {"cmpleui", "t,s,u", "t,s,u,E", 3, 4, iw_F2I16_type,
+   MATCH_R2_CMPLEUI, MASK_R2_CMPLEUI,
+   NIOS2_INSN_MACRO, unsigned_immed16_overflow},
+  {"cmplt", "d,s,t", "d,s,t,E", 3, 4, iw_F3X6_type,
+   MATCH_R2_CMPLT, MASK_R2_CMPLT, 0, no_overflow},
+  {"cmplti", "t,s,i", "t,s,i,E", 3, 4, iw_F2I16_type,
+   MATCH_R2_CMPLTI, MASK_R2_CMPLTI, 0, signed_immed16_overflow},
+  {"cmpltu", "d,s,t", "d,s,t,E", 3, 4, iw_F3X6_type,
+   MATCH_R2_CMPLTU, MASK_R2_CMPLTU, 0, no_overflow},
+  {"cmpltui", "t,s,u", "t,s,u,E", 3, 4, iw_F2I16_type,
+   MATCH_R2_CMPLTUI, MASK_R2_CMPLTUI, 0, unsigned_immed16_overflow},
+  {"cmpne", "d,s,t", "d,s,t,E", 3, 4, iw_F3X6_type,
+   MATCH_R2_CMPNE, MASK_R2_CMPNE, 0, no_overflow},
+  {"cmpnei", "t,s,i", "t,s,i,E", 3, 4, iw_F2I16_type,
+   MATCH_R2_CMPNEI, MASK_R2_CMPNEI, 0, signed_immed16_overflow},
+  {"custom", "l,d,s,t", "l,d,s,t,E", 4, 4, iw_F3X8_type,
+   MATCH_R2_CUSTOM, MASK_R2_CUSTOM, 0, custom_opcode_overflow},
+  {"div", "d,s,t", "d,s,t,E", 3, 4, iw_F3X6_type,
+   MATCH_R2_DIV, MASK_R2_DIV, 0, no_overflow},
+  {"divu", "d,s,t", "d,s,t,E", 3, 4, iw_F3X6_type,
+   MATCH_R2_DIVU, MASK_R2_DIVU, 0, no_overflow},
+  {"eni", "j", "j,E", 1, 4, iw_F3X6L5_type,
+   MATCH_R2_ENI, MASK_R2_ENI, NIOS2_INSN_OPTARG, no_overflow},
+  {"eret", "", "E", 0, 4, iw_F3X6_type,
+   MATCH_R2_ERET, MASK_R2_ERET, 0, no_overflow},
+  {"extract", "t,s,j,k", "t,s,j,k,E", 4, 4, iw_F2X6L10_type,
+   MATCH_R2_EXTRACT, MASK_R2_EXTRACT, 0, no_overflow},
+  {"flushd", "I(s)", "I(s),E", 2, 4, iw_F1X4I12_type,
+   MATCH_R2_FLUSHD, MASK_R2_FLUSHD, 0, address_offset_overflow},
+  {"flushda", "I(s)", "I(s),E", 2, 4, iw_F1X4I12_type,
+   MATCH_R2_FLUSHDA, MASK_R2_FLUSHDA, 0, address_offset_overflow},
+  {"flushi", "s", "s,E", 1, 4, iw_F3X6_type,
+   MATCH_R2_FLUSHI, MASK_R2_FLUSHI, 0, no_overflow},
+  {"flushp", "", "E", 0, 4, iw_F3X6_type,
+   MATCH_R2_FLUSHP, MASK_R2_FLUSHP, 0, no_overflow},
+  {"initd", "I(s)", "I(s),E", 2, 4, iw_F1X4I12_type,
+   MATCH_R2_INITD, MASK_R2_INITD, 0, address_offset_overflow},
+  {"initda", "I(s)", "I(s),E", 2, 4, iw_F1X4I12_type,
+   MATCH_R2_INITDA, MASK_R2_INITDA, 0, address_offset_overflow},
+  {"initi", "s", "s,E", 1, 4, iw_F3X6_type,
+   MATCH_R2_INITI, MASK_R2_INITI, 0, no_overflow},
+  {"insert", "t,s,j,k", "t,s,j,k,E", 4, 4, iw_F2X6L10_type,
+   MATCH_R2_INSERT, MASK_R2_INSERT, 0, no_overflow},
+  {"jmp", "s", "s,E", 1, 4, iw_F3X6_type,
+   MATCH_R2_JMP, MASK_R2_JMP, 0, no_overflow},
+  {"jmpi", "m", "m,E", 1, 4, iw_L26_type,
+   MATCH_R2_JMPI, MASK_R2_JMPI, 0, call_target_overflow},
+  {"jmpr.n", "s", "s,E", 1, 2, iw_F1X1_type,
+   MATCH_R2_JMPR_N, MASK_R2_JMPR_N, 0, no_overflow},
+  {"ldb", "t,i(s)", "t,i(s),E", 3, 4, iw_F2I16_type,
+   MATCH_R2_LDB, MASK_R2_LDB, 0, address_offset_overflow},
+  {"ldbio", "t,I(s)", "t,I(s),E", 3, 4, iw_F2X4I12_type,
+   MATCH_R2_LDBIO, MASK_R2_LDBIO, 0, signed_immed12_overflow},
+  {"ldbu", "t,i(s)", "t,i(s),E", 3, 4, iw_F2I16_type,
+   MATCH_R2_LDBU, MASK_R2_LDBU, 0, address_offset_overflow},
+  {"ldbuio", "t,I(s)", "t,I(s),E", 3, 4, iw_F2X4I12_type,
+   MATCH_R2_LDBUIO, MASK_R2_LDBUIO, 0, signed_immed12_overflow},
+  {"ldbu.n", "T,Y(S)", "T,Y(S),E", 3, 2, iw_T2I4_type,
+   MATCH_R2_LDBU_N, MASK_R2_LDBU_N, 0, address_offset_overflow},
+  {"ldex", "d,(s)", "d,(s),E", 2, 4, iw_F3X6_type,
+   MATCH_R2_LDEX, MASK_R2_LDEX, 0, no_overflow},
+  {"ldh", "t,i(s)", "t,i(s),E", 3, 4, iw_F2I16_type,
+   MATCH_R2_LDH, MASK_R2_LDH, 0, address_offset_overflow},
+  {"ldhio", "t,I(s)", "t,I(s),E", 3, 4, iw_F2X4I12_type,
+   MATCH_R2_LDHIO, MASK_R2_LDHIO, 0, signed_immed12_overflow},
+  {"ldhu", "t,i(s)", "t,i(s),E", 3, 4, iw_F2I16_type,
+   MATCH_R2_LDHU, MASK_R2_LDHU, 0, address_offset_overflow},
+  {"ldhuio", "t,I(s)", "t,I(s),E", 3, 4, iw_F2X4I12_type,
+   MATCH_R2_LDHUIO, MASK_R2_LDHUIO, 0, signed_immed12_overflow},
+  {"ldhu.n", "T,X(S)", "T,X(S),E", 3, 2, iw_T2I4_type,
+   MATCH_R2_LDHU_N, MASK_R2_LDHU_N, 0, address_offset_overflow},
+  {"ldsex", "d,(s)", "d,(s),E", 2, 4, iw_F3X6_type,
+   MATCH_R2_LDSEX, MASK_R2_LDSEX, 0, no_overflow},
+  {"ldw", "t,i(s)", "t,i(s),E", 3, 4, iw_F2I16_type,
+   MATCH_R2_LDW, MASK_R2_LDW, 0, address_offset_overflow},
+  {"ldwio", "t,I(s)", "t,I(s),E", 3, 4, iw_F2X4I12_type,
+   MATCH_R2_LDWIO, MASK_R2_LDWIO, 0, signed_immed12_overflow},
+  {"ldwm", "R,B", "R,B,E", 2, 4, iw_F1X4L17_type,
+   MATCH_R2_LDWM, MASK_R2_LDWM, 0, no_overflow},
+  {"ldw.n", "T,W(S)", "T,W(S),E", 3, 2, iw_T2I4_type,
+   MATCH_R2_LDW_N, MASK_R2_LDW_N, 0, address_offset_overflow},
+  {"ldwsp.n", "t,V(s)", "t,V(s),E", 3, 2, iw_F1I5_type,
+   MATCH_R2_LDWSP_N, MASK_R2_LDWSP_N, 0, address_offset_overflow},
+  {"merge", "t,s,j,k", "t,s,j,k,E", 4, 4, iw_F2X6L10_type,
+   MATCH_R2_MERGE, MASK_R2_MERGE, 0, no_overflow},
+  {"mov", "d,s", "d,s,E", 2, 4, iw_F3X6_type,
+   MATCH_R2_MOV, MASK_R2_MOV, NIOS2_INSN_MACRO_MOV, no_overflow},
+  {"mov.n", "d,s", "d,s,E", 2, 2, iw_F2_type,
+   MATCH_R2_MOV_N, MASK_R2_MOV_N, 0, no_overflow},
+  {"movi.n", "D,h", "D,h,E", 2, 2, iw_T1I7_type,
+   MATCH_R2_MOVI_N, MASK_R2_MOVI_N, 0, enumeration_overflow},
+  {"movhi", "t,u", "t,u,E", 2, 4, iw_F2I16_type,
+   MATCH_R2_MOVHI, MASK_R2_MOVHI,
+   NIOS2_INSN_MACRO_MOVI, unsigned_immed16_overflow},
+  {"movi", "t,i", "t,i,E", 2, 4, iw_F2I16_type,
+   MATCH_R2_MOVI, MASK_R2_MOVI, NIOS2_INSN_MACRO_MOVI, signed_immed16_overflow},
+  {"movia", "t,o", "t,o,E", 2, 4, iw_F2I16_type,
+   MATCH_R2_ORHI, MASK_R2_ORHI, NIOS2_INSN_MACRO_MOVIA, no_overflow},
+  {"movui", "t,u", "t,u,E", 2, 4, iw_F2I16_type,
+   MATCH_R2_MOVUI, MASK_R2_MOVUI,
+   NIOS2_INSN_MACRO_MOVI, unsigned_immed16_overflow},
+  {"mul", "d,s,t", "d,s,t,E", 3, 4, iw_F3X6_type,
+   MATCH_R2_MUL, MASK_R2_MUL, 0, no_overflow},
+  {"muli", "t,s,i", "t,s,i,E", 3, 4, iw_F2I16_type,
+   MATCH_R2_MULI, MASK_R2_MULI, 0, signed_immed16_overflow},
+  {"mulxss", "d,s,t", "d,s,t,E", 3, 4, iw_F3X6_type,
+   MATCH_R2_MULXSS, MASK_R2_MULXSS, 0, no_overflow},
+  {"mulxsu", "d,s,t", "d,s,t,E", 3, 4, iw_F3X6_type,
+   MATCH_R2_MULXSU, MASK_R2_MULXSU, 0, no_overflow},
+  {"mulxuu", "d,s,t", "d,s,t,E", 3, 4, iw_F3X6_type,
+   MATCH_R2_MULXUU, MASK_R2_MULXUU, 0, no_overflow},
+  /* The encoding of the neg.n operands is backwards, not
+     the interpretation -- the first operand is still the
+     destination and the second the source.  */
+  {"neg.n", "S,D", "S,D,E", 2, 2, iw_T2X3_type,
+   MATCH_R2_NEG_N, MASK_R2_NEG_N, 0, no_overflow},
+  {"nextpc", "d", "d,E", 1, 4, iw_F3X6_type,
+   MATCH_R2_NEXTPC, MASK_R2_NEXTPC, 0, no_overflow},
+  {"nop", "", "E", 0, 4, iw_F3X6_type,
+   MATCH_R2_NOP, MASK_R2_NOP, NIOS2_INSN_MACRO_MOV, no_overflow},
+  {"nop.n", "", "E", 0, 2, iw_F2_type,
+   MATCH_R2_NOP_N, MASK_R2_NOP_N, NIOS2_INSN_MACRO_MOV, no_overflow},
+  {"nor", "d,s,t", "d,s,t,E", 3, 4, iw_F3X6_type,
+   MATCH_R2_NOR, MASK_R2_NOR, 0, no_overflow},
+  {"not.n", "D,S", "D,S,E", 2, 2, iw_T2X3_type,
+   MATCH_R2_NOT_N, MASK_R2_NOT_N, 0, no_overflow},
+  {"or", "d,s,t", "d,s,t,E", 3, 4, iw_F3X6_type,
+   MATCH_R2_OR, MASK_R2_OR, 0, no_overflow},
+  {"orhi", "t,s,u", "t,s,u,E", 3, 4, iw_F2I16_type,
+   MATCH_R2_ORHI, MASK_R2_ORHI, 0, unsigned_immed16_overflow},
+  {"ori", "t,s,u", "t,s,u,E", 3, 4, iw_F2I16_type,
+   MATCH_R2_ORI, MASK_R2_ORI, 0, unsigned_immed16_overflow},
+  {"or.n", "D,S,T", "D,S,T,E", 3, 2, iw_T2X3_type,
+   MATCH_R2_OR_N, MASK_R2_OR_N, 0, no_overflow},
+  {"pop.n", "R,W", "R,W,E", 2, 2, iw_L5I4X1_type,
+   MATCH_R2_POP_N, MASK_R2_POP_N, NIOS2_INSN_OPTARG, no_overflow},
+  {"push.n", "R,W", "R,W,E", 2, 2, iw_L5I4X1_type,
+   MATCH_R2_PUSH_N, MASK_R2_PUSH_N, NIOS2_INSN_OPTARG, no_overflow},
+  {"rdctl", "d,c", "d,c,E", 2, 4, iw_F3X6L5_type,
+   MATCH_R2_RDCTL, MASK_R2_RDCTL, 0, no_overflow},
+  {"rdprs", "t,s,I", "t,s,I,E", 3, 4, iw_F2X4I12_type,
+   MATCH_R2_RDPRS, MASK_R2_RDPRS, 0, signed_immed12_overflow},
+  {"ret", "", "E", 0, 4, iw_F3X6_type,
+   MATCH_R2_RET, MASK_R2_RET, 0, no_overflow},
+  {"ret.n", "", "E", 0, 2, iw_X2L5_type,
+   MATCH_R2_RET_N, MASK_R2_RET_N, 0, no_overflow},
+  {"rol", "d,s,t", "d,s,t,E", 3, 4, iw_F3X6_type,
+   MATCH_R2_ROL, MASK_R2_ROL, 0, no_overflow},
+  {"roli", "d,s,j", "d,s,j,E", 3, 4, iw_F3X6L5_type,
+   MATCH_R2_ROLI, MASK_R2_ROLI, 0, unsigned_immed5_overflow},
+  {"ror", "d,s,t", "d,s,t,E", 3, 4, iw_F3X6_type,
+   MATCH_R2_ROR, MASK_R2_ROR, 0, no_overflow},
+  {"sll", "d,s,t", "d,s,t,E", 3, 4, iw_F3X6_type,
+   MATCH_R2_SLL, MASK_R2_SLL, 0, no_overflow},
+  {"slli", "d,s,j", "d,s,j,E", 3, 4, iw_F3X6L5_type,
+   MATCH_R2_SLLI, MASK_R2_SLLI, 0, unsigned_immed5_overflow},
+  {"sll.n", "D,S,T", "D,S,T,E", 3, 2, iw_T2X3_type,
+   MATCH_R2_SLL_N, MASK_R2_SLL_N, 0, no_overflow},
+  {"slli.n", "D,S,f", "D,S,f,E", 3, 2, iw_T2X1L3_type,
+   MATCH_R2_SLLI_N, MASK_R2_SLLI_N, 0, enumeration_overflow},
+  {"spaddi.n", "D,U", "D,U,E", 2, 2, iw_T1I7_type,
+   MATCH_R2_SPADDI_N, MASK_R2_SPADDI_N, 0, address_offset_overflow},
+  {"spdeci.n", "U", "U,E", 1, 2, iw_X1I7_type,
+   MATCH_R2_SPDECI_N, MASK_R2_SPDECI_N, 0, address_offset_overflow},
+  {"spinci.n", "U", "U,E", 1, 2, iw_X1I7_type,
+   MATCH_R2_SPINCI_N, MASK_R2_SPINCI_N, 0, address_offset_overflow},
+  {"sra", "d,s,t", "d,s,t,E", 3, 4, iw_F3X6_type,
+   MATCH_R2_SRA, MASK_R2_SRA, 0, no_overflow},
+  {"srai", "d,s,j", "d,s,j,E", 3, 4, iw_F3X6L5_type,
+   MATCH_R2_SRAI, MASK_R2_SRAI, 0, unsigned_immed5_overflow},
+  {"srl", "d,s,t", "d,s,t,E", 3, 4, iw_F3X6_type,
+   MATCH_R2_SRL, MASK_R2_SRL, 0, no_overflow},
+  {"srli", "d,s,j", "d,s,j,E", 3, 4, iw_F3X6L5_type,
+   MATCH_R2_SRLI, MASK_R2_SRLI, 0, unsigned_immed5_overflow},
+  {"srl.n", "D,S,T", "D,S,T,E", 3, 2, iw_T2X3_type,
+   MATCH_R2_SRL_N, MASK_R2_SRL_N, 0, no_overflow},
+  {"srli.n", "D,S,f", "D,S,f,E", 3, 2, iw_T2X1L3_type,
+   MATCH_R2_SRLI_N, MASK_R2_SRLI_N, 0, enumeration_overflow},
+  {"stb", "t,i(s)", "t,i(s),E", 3, 4, iw_F2I16_type,
+   MATCH_R2_STB, MASK_R2_STB, 0, address_offset_overflow},
+  {"stbio", "t,I(s)", "t,I(s),E", 3, 4, iw_F2X4I12_type,
+   MATCH_R2_STBIO, MASK_R2_STBIO, 0, signed_immed12_overflow},
+  {"stb.n", "T,Y(S)", "T,Y(S),E", 3, 2, iw_T2I4_type,
+   MATCH_R2_STB_N, MASK_R2_STB_N, 0, address_offset_overflow},
+  {"stbz.n", "t,M(S)", "t,M(S),E", 3, 2, iw_T1X1I6_type,
+   MATCH_R2_STBZ_N, MASK_R2_STBZ_N, 0, address_offset_overflow},
+  {"stex", "d,t,(s)", "d,t,(s),E", 3, 4, iw_F3X6_type,
+   MATCH_R2_STEX, MASK_R2_STEX, 0, no_overflow},
+  {"sth", "t,i(s)", "t,i(s),E", 3, 4, iw_F2I16_type,
+   MATCH_R2_STH, MASK_R2_STH, 0, address_offset_overflow},
+  {"sthio", "t,I(s)", "t,I(s),E", 3, 4, iw_F2X4I12_type,
+   MATCH_R2_STHIO, MASK_R2_STHIO, 0, signed_immed12_overflow},
+  {"sth.n", "T,X(S)", "T,X(S),E", 3, 2, iw_T2I4_type,
+   MATCH_R2_STH_N, MASK_R2_STH_N, 0, address_offset_overflow},
+  {"stsex", "d,t,(s)", "d,t,(s),E", 3, 4, iw_F3X6_type,
+   MATCH_R2_STSEX, MASK_R2_STSEX, 0, no_overflow},
+  {"stw", "t,i(s)", "t,i(s),E", 3, 4, iw_F2I16_type,
+   MATCH_R2_STW, MASK_R2_STW, 0, address_offset_overflow},
+  {"stwio", "t,I(s)", "t,I(s),E", 3, 4, iw_F2X4I12_type,
+   MATCH_R2_STWIO, MASK_R2_STWIO, 0, signed_immed12_overflow},
+  {"stwm", "R,B", "R,B,E", 2, 4, iw_F1X4L17_type,
+   MATCH_R2_STWM, MASK_R2_STWM, 0, no_overflow},
+  {"stwsp.n", "t,V(s)", "t,V(s),E", 3, 2, iw_F1I5_type,
+   MATCH_R2_STWSP_N, MASK_R2_STWSP_N, 0, address_offset_overflow},
+  {"stw.n", "T,W(S)", "T,W(S),E", 3, 2, iw_T2I4_type,
+   MATCH_R2_STW_N, MASK_R2_STW_N, 0, address_offset_overflow},
+  {"stwz.n", "t,N(S)", "t,N(S),E", 3, 2, iw_T1X1I6_type,
+   MATCH_R2_STWZ_N, MASK_R2_STWZ_N, 0, address_offset_overflow},
+  {"sub", "d,s,t", "d,s,t,E", 3, 4, iw_F3X6_type,
+   MATCH_R2_SUB, MASK_R2_SUB, 0, no_overflow},
+  {"subi", "t,s,i", "t,s,i,E", 3, 4, iw_F2I16_type,
+   MATCH_R2_SUBI, MASK_R2_SUBI, NIOS2_INSN_MACRO, signed_immed16_overflow},
+  {"sub.n", "D,S,T", "D,S,T,E", 3, 2, iw_T3X1_type,
+   MATCH_R2_SUB_N, MASK_R2_SUB_N, 0, no_overflow},
+  {"subi.n", "D,S,e", "D,S,e,E", 3, 2, iw_T2X1I3_type,
+   MATCH_R2_SUBI_N, MASK_R2_SUBI_N, 0, enumeration_overflow},
+  {"sync", "", "E", 0, 4, iw_F3X6_type,
+   MATCH_R2_SYNC, MASK_R2_SYNC, 0, no_overflow},
+  {"trap", "j", "j,E", 1, 4, iw_F3X6L5_type,
+   MATCH_R2_TRAP, MASK_R2_TRAP, NIOS2_INSN_OPTARG, no_overflow},
+  {"trap.n", "j", "j,E", 1, 2, iw_X2L5_type,
+   MATCH_R2_TRAP_N, MASK_R2_TRAP_N, NIOS2_INSN_OPTARG, no_overflow},
+  {"wrctl", "c,s", "c,s,E", 2, 4, iw_F3X6L5_type,
+   MATCH_R2_WRCTL, MASK_R2_WRCTL, 0, no_overflow},
+  {"wrpie", "d,s", "d,s,E", 2, 4, iw_F3X6L5_type,
+   MATCH_R2_WRPIE, MASK_R2_WRPIE, 0, no_overflow},
+  {"wrprs", "d,s", "d,s,E", 2, 4, iw_F3X6_type,
+   MATCH_R2_WRPRS, MASK_R2_WRPRS, 0, no_overflow},
+  {"xor", "d,s,t", "d,s,t,E", 3, 4, iw_F3X6_type,
+   MATCH_R2_XOR, MASK_R2_XOR, 0, no_overflow},
+  {"xorhi", "t,s,u", "t,s,u,E", 3, 4, iw_F2I16_type,
+   MATCH_R2_XORHI, MASK_R2_XORHI, 0, unsigned_immed16_overflow},
+  {"xori", "t,s,u", "t,s,u,E", 3, 4, iw_F2I16_type,
+   MATCH_R2_XORI, MASK_R2_XORI, 0, unsigned_immed16_overflow},
+  {"xor.n", "D,S,T", "D,S,T,E", 3, 2, iw_T2X3_type,
+   MATCH_R2_XOR_N, MASK_R2_XOR_N, 0, no_overflow},
+};
+
+#define NIOS2_NUM_R2_OPCODES \
+       ((sizeof nios2_r2_opcodes) / (sizeof (nios2_r2_opcodes[0])))
+const int nios2_num_r2_opcodes = NIOS2_NUM_R2_OPCODES;
+
+/* Default to using the R1 instruction tables.  */
 struct nios2_opcode *nios2_opcodes = (struct nios2_opcode *) nios2_r1_opcodes;
-int nios2_num_opcodes = NIOS2_NUM_OPCODES;
-#undef NIOS2_NUM_OPCODES
+int nios2_num_opcodes = NIOS2_NUM_R1_OPCODES;
+#undef NIOS2_NUM_R1_OPCODES
+#undef NIOS2_NUM_R2_OPCODES
+
+/* Decodings for R2 asi.n (addi.n/subi.n) immediate values.  */
+unsigned int nios2_r2_asi_n_mappings[] =
+  {1, 2, 4, 8, 16, 32, 64, 128};
+const int nios2_num_r2_asi_n_mappings = 8;
+
+/* Decodings for R2 shi.n (slli.n/srli.n) immediate values.  */
+unsigned int nios2_r2_shi_n_mappings[] =
+  {1, 2, 3, 8, 12, 16, 24, 31};
+const int nios2_num_r2_shi_n_mappings = 8;
+
+/* Decodings for R2 andi.n immediate values.  */
+unsigned int nios2_r2_andi_n_mappings[] =
+  {1, 2, 3, 4, 8, 0xf, 0x10, 0x1f,
+   0x20, 0x3f, 0x7f, 0x80, 0xff, 0x7ff, 0xff00, 0xffff};
+const int nios2_num_r2_andi_n_mappings = 16;
+
+/* Decodings for R2 3-bit register fields.  */
+int nios2_r2_reg3_mappings[] =
+  {16, 17, 2, 3, 4, 5, 6, 7};
+const int nios2_num_r2_reg3_mappings = 8;
+
+/* Decodings for R2 push.n/pop.n REG_RANGE value list.  */
+unsigned long nios2_r2_reg_range_mappings[] = {
+  0x00010000,
+  0x00030000,
+  0x00070000,
+  0x000f0000,
+  0x001f0000,
+  0x003f0000,
+  0x007f0000,
+  0x00ff0000
+};
+const int nios2_num_r2_reg_range_mappings = 8;