include/opcode/nios2.h

   1 /* Nios II opcode list for GAS, the GNU assembler.
   2    Copyright (C) 2012-2015 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 #ifdef __cplusplus
  29 extern "C" {
  30 #endif
  31
  32 /****************************************************************************
  33  * This file contains structures, bit masks and shift counts used
  34  * by the GNU toolchain to define the Nios II instruction set and
  35  * access various opcode fields.
  36  ****************************************************************************/
  37
  38 /* Instruction encoding formats.  */
  39 enum iw_format_type {
  40   /* R1 formats */
  41   iw_i_type,
  42   iw_r_type,
  43   iw_j_type,
  44   iw_custom_type
  45 };
  46
  47 /* Identify different overflow situations for error messages.  */
  48 enum overflow_type
  49 {
  50   call_target_overflow = 0,
  51   branch_target_overflow,
  52   address_offset_overflow,
  53   signed_immed16_overflow,
  54   unsigned_immed16_overflow,
  55   unsigned_immed5_overflow,
  56   custom_opcode_overflow,
  57   no_overflow
  58 };
  59
  60 /* This structure holds information for a particular instruction.
  61
  62    The args field is a string describing the operands.  The following
  63    letters can appear in the args:
  64      c - a 5-bit control register index
  65      d - a 5-bit destination register index
  66      s - a 5-bit left source register index
  67      t - a 5-bit right source register index
  68      i - a 16-bit signed immediate
  69      u - a 16-bit unsigned immediate
  70      o - a 16-bit signed program counter relative offset
  71      j - a 5-bit unsigned immediate
  72      l - a 8-bit custom instruction constant
  73      m - a 26-bit unsigned immediate
  74    Literal ',', '(', and ')' characters may also appear in the args as
  75    delimiters.
  76
  77    Note that the args describe the semantics and assembly-language syntax
  78    of the operands, not their encoding into the instruction word.
  79
  80    The pinfo field is INSN_MACRO for a macro.  Otherwise, it is a collection
  81    of bits describing the instruction, notably any relevant hazard
  82    information.
  83
  84    When assembling, the match field contains the opcode template, which
  85    is modified by the arguments to produce the actual opcode
  86    that is emitted.  If pinfo is INSN_MACRO, then this is 0.
  87
  88    If pinfo is INSN_MACRO, the mask field stores the macro identifier.
  89    Otherwise this is a bit mask for the relevant portions of the opcode
  90    when disassembling.  If the actual opcode anded with the match field
  91    equals the opcode field, then we have found the correct instruction.  */
  92
  93 struct nios2_opcode
  94 {
  95   const char *name;             /* The name of the instruction.  */
  96   const char *args;             /* A string describing the arguments for this
  97                                    instruction.  */
  98   const char *args_test;        /* Like args, but with an extra argument for
  99                                    the expected opcode.  */
 100   unsigned long num_args;       /* The number of arguments the instruction
 101                                    takes.  */
 102   unsigned size;                /* Size in bytes of the instruction.  */
 103   enum iw_format_type format;   /* Instruction format.  */
 104   unsigned long match;          /* The basic opcode for the instruction.  */
 105   unsigned long mask;           /* Mask for the opcode field of the
 106                                    instruction.  */
 107   unsigned long pinfo;          /* Is this a real instruction or instruction
 108                                    macro?  */
 109   enum overflow_type overflow_msg;  /* Used to generate informative
 110                                        message when fixup overflows.  */
 111 };
 112
 113 /* This value is used in the nios2_opcode.pinfo field to indicate that the
 114    instruction is a macro or pseudo-op.  This requires special treatment by
 115    the assembler, and is used by the disassembler to determine whether to
 116    check for a nop.  */
 117 #define NIOS2_INSN_MACRO        0x80000000
 118 #define NIOS2_INSN_MACRO_MOV    0x80000001
 119 #define NIOS2_INSN_MACRO_MOVI   0x80000002
 120 #define NIOS2_INSN_MACRO_MOVIA  0x80000004
 121
 122 #define NIOS2_INSN_RELAXABLE    0x40000000
 123 #define NIOS2_INSN_UBRANCH      0x00000010
 124 #define NIOS2_INSN_CBRANCH      0x00000020
 125 #define NIOS2_INSN_CALL         0x00000040
 126
 127 #define NIOS2_INSN_OPTARG       0x00000080
 128
 129 /* Register attributes.  */
 130 #define REG_NORMAL      (1<<0)  /* Normal registers.  */
 131 #define REG_CONTROL     (1<<1)  /* Control registers.  */
 132 #define REG_COPROCESSOR (1<<2)  /* For custom instructions.  */
 133
 134 struct nios2_reg
 135 {
 136   const char *name;
 137   const int index;
 138   unsigned long regtype;
 139 };
 140
 141 /* Pull in the instruction field accessors, opcodes, and masks.  */
 142 #include "nios2r1.h"
 143
 144 /* These are the data structures used to hold the instruction information.  */
 145 extern const struct nios2_opcode nios2_r1_opcodes[];
 146 extern const int nios2_num_r1_opcodes;
 147 extern struct nios2_opcode *nios2_opcodes;
 148 extern int nios2_num_opcodes;
 149
 150 /* These are the data structures used to hold the register information.  */
 151 extern const struct nios2_reg nios2_builtin_regs[];
 152 extern struct nios2_reg *nios2_regs;
 153 extern const int nios2_num_builtin_regs;
 154 extern int nios2_num_regs;
 155
 156 /* Return the opcode descriptor for a single instruction.  */
 157 extern const struct nios2_opcode *
 158 nios2_find_opcode_hash (unsigned long, unsigned long);
 159
 160 #ifdef __cplusplus
 161 }
 162 #endif
 163
 164 #endif /* _NIOS2_H */