include/opcode/nios2.h

   1 /* Nios II opcode list for GAS, the GNU assembler.
   2    Copyright (C) 2012-2014 Free Software Foundation, Inc.
   3    Contributed by Nigel Gray (ngray@altera.com).
   4    Contributed by Mentor Graphics, Inc.
   5
   6    This file is part of GAS, the GNU Assembler, and GDB, the GNU disassembler.
   7
   8    GAS/GDB is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3, or (at your option)
  11    any later version.
  12
  13    GAS/GDB is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with GAS or GDB; see the file COPYING3.  If not, write to
  20    the Free Software Foundation, 51 Franklin Street - Fifth Floor,
  21    Boston, MA 02110-1301, USA.  */
  22
  23 #ifndef _NIOS2_H_
  24 #define _NIOS2_H_
  25
  26 #include "bfd.h"
  27
  28 /****************************************************************************
  29  * This file contains structures, bit masks and shift counts used
  30  * by the GNU toolchain to define the Nios II instruction set and
  31  * access various opcode fields.
  32  ****************************************************************************/
  33
  34 /* Instruction encoding formats.  */
  35 enum iw_format_type {
  36   /* R1 formats */
  37   iw_i_type,
  38   iw_r_type,
  39   iw_j_type,
  40   iw_custom_type
  41 };
  42
  43 /* Identify different overflow situations for error messages.  */
  44 enum overflow_type
  45 {
  46   call_target_overflow = 0,
  47   branch_target_overflow,
  48   address_offset_overflow,
  49   signed_immed16_overflow,
  50   unsigned_immed16_overflow,
  51   unsigned_immed5_overflow,
  52   custom_opcode_overflow,
  53   no_overflow
  54 };
  55
  56 /* This structure holds information for a particular instruction.
  57
  58    The args field is a string describing the operands.  The following
  59    letters can appear in the args:
  60      c - a 5-bit control register index
  61      d - a 5-bit destination register index
  62      s - a 5-bit left source register index
  63      t - a 5-bit right source register index
  64      i - a 16-bit signed immediate
  65      u - a 16-bit unsigned immediate
  66      o - a 16-bit signed program counter relative offset
  67      j - a 5-bit unsigned immediate
  68      l - a 8-bit custom instruction constant
  69      m - a 26-bit unsigned immediate
  70    Literal ',', '(', and ')' characters may also appear in the args as
  71    delimiters.
  72
  73    Note that the args describe the semantics and assembly-language syntax
  74    of the operands, not their encoding into the instruction word.
  75
  76    The pinfo field is INSN_MACRO for a macro.  Otherwise, it is a collection
  77    of bits describing the instruction, notably any relevant hazard
  78    information.
  79
  80    When assembling, the match field contains the opcode template, which
  81    is modified by the arguments to produce the actual opcode
  82    that is emitted.  If pinfo is INSN_MACRO, then this is 0.
  83
  84    If pinfo is INSN_MACRO, the mask field stores the macro identifier.
  85    Otherwise this is a bit mask for the relevant portions of the opcode
  86    when disassembling.  If the actual opcode anded with the match field
  87    equals the opcode field, then we have found the correct instruction.  */
  88
  89 struct nios2_opcode
  90 {
  91   const char *name;             /* The name of the instruction.  */
  92   const char *args;             /* A string describing the arguments for this
  93                                    instruction.  */
  94   const char *args_test;        /* Like args, but with an extra argument for
  95                                    the expected opcode.  */
  96   unsigned long num_args;       /* The number of arguments the instruction
  97                                    takes.  */
  98   unsigned size;                /* Size in bytes of the instruction.  */
  99   enum iw_format_type format;   /* Instruction format.  */
 100   unsigned long match;          /* The basic opcode for the instruction.  */
 101   unsigned long mask;           /* Mask for the opcode field of the
 102                                    instruction.  */
 103   unsigned long pinfo;          /* Is this a real instruction or instruction
 104                                    macro?  */
 105   enum overflow_type overflow_msg;  /* Used to generate informative
 106                                        message when fixup overflows.  */
 107 };
 108
 109 /* This value is used in the nios2_opcode.pinfo field to indicate that the
 110    instruction is a macro or pseudo-op.  This requires special treatment by
 111    the assembler, and is used by the disassembler to determine whether to
 112    check for a nop.  */
 113 #define NIOS2_INSN_MACRO        0x80000000
 114 #define NIOS2_INSN_MACRO_MOV    0x80000001
 115 #define NIOS2_INSN_MACRO_MOVI   0x80000002
 116 #define NIOS2_INSN_MACRO_MOVIA  0x80000004
 117
 118 #define NIOS2_INSN_RELAXABLE    0x40000000
 119 #define NIOS2_INSN_UBRANCH      0x00000010
 120 #define NIOS2_INSN_CBRANCH      0x00000020
 121 #define NIOS2_INSN_CALL         0x00000040
 122
 123 #define NIOS2_INSN_ADDI         0x00000080
 124 #define NIOS2_INSN_ANDI         0x00000100
 125 #define NIOS2_INSN_ORI          0x00000200
 126 #define NIOS2_INSN_XORI         0x00000400
 127
 128 #define NIOS2_INSN_OPTARG       0x00000800
 129
 130 /* Register attributes.  */
 131 #define REG_NORMAL      (1<<0)  /* Normal registers.  */
 132 #define REG_CONTROL     (1<<1)  /* Control registers.  */
 133 #define REG_COPROCESSOR (1<<2)  /* For custom instructions.  */
 134
 135 struct nios2_reg
 136 {
 137   const char *name;
 138   const int index;
 139   unsigned long regtype;
 140 };
 141
 142 /* Pull in the instruction field accessors, opcodes, and masks.  */
 143 #include "nios2r1.h"
 144
 145 /* These are the data structures used to hold the instruction information.  */
 146 extern const struct nios2_opcode nios2_r1_opcodes[];
 147 extern const int nios2_num_r1_opcodes;
 148 extern struct nios2_opcode *nios2_opcodes;
 149 extern int nios2_num_opcodes;
 150
 151 /* These are the data structures used to hold the register information.  */
 152 extern const struct nios2_reg nios2_builtin_regs[];
 153 extern struct nios2_reg *nios2_regs;
 154 extern const int nios2_num_builtin_regs;
 155 extern int nios2_num_regs;
 156
 157 /* This is made extern so that the assembler can use it to find out
 158    what instruction caused an error.  */
 159 extern const struct nios2_opcode *nios2_find_opcode_hash (unsigned long);
 160
 161 #endif /* _NIOS2_H */