sim/igen/gen-semantics.h

   1 /* The IGEN simulator generator for GDB, the GNU Debugger.
   2
   3    Copyright 2002, 2007 Free Software Foundation, Inc.
   4
   5    Contributed by Andrew Cagney.
   6
   7    This file is part of GDB.
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 2 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program; if not, write to the Free Software
  21    Foundation, Inc., 59 Temple Place - Suite 330,
  22    Boston, MA 02111-1307, USA.  */
  23
  24
  25 /* Creates the files semantics.[hc].
  26
  27    The generated file semantics contains functions that implement the
  28    operations required to model a single target processor instruction.
  29
  30    Several different variations on the semantics file can be created:
  31
  32         o       uncached
  33
  34                 No instruction cache exists.  The semantic function
  35                 needs to generate any required values locally.
  36
  37         o       cached - separate cracker and semantic
  38
  39                 Two independant functions are created.  Firstly the
  40                 function that cracks an instruction entering it into a
  41                 cache and secondly the semantic function propper that
  42                 uses the cache.
  43
  44         o       cached - semantic + cracking semantic
  45
  46                 The function that cracks the instruction and enters
  47                 all values into the cache also contains a copy of the
  48                 semantic code (avoiding the need to call both the
  49                 cracker and the semantic function when there is a
  50                 cache miss).
  51
  52    For each of these general forms, several refinements can occure:
  53
  54         o       do/don't duplicate/expand semantic functions
  55
  56                 As a consequence of decoding an instruction, the
  57                 decoder, as part of its table may have effectivly made
  58                 certain of the variable fields in an instruction
  59                 constant. Separate functions for each of the
  60                 alternative values for what would have been treated as
  61                 a variable part can be created.
  62
  63         o       use cache struct directly.
  64
  65                 When a cracking cache is present, the semantic
  66                 functions can be generated to either hold intermediate
  67                 cache values in local variables or always refer to the
  68                 contents of the cache directly. */
  69
  70
  71
  72
  73
  74
  75 extern void print_semantic_declaration
  76   (lf *file,
  77    insn_entry * insn,
  78    opcode_bits *bits, insn_opcodes *opcodes, int nr_prefetched_words);
  79
  80 extern void print_semantic_definition
  81   (lf *file,
  82    insn_entry * insn,
  83    opcode_bits *bits,
  84    insn_opcodes *opcodes, cache_entry *cache_rules, int nr_prefetched_words);
  85
  86
  87 typedef enum
  88 {
  89   invalid_illegal,
  90   invalid_fp_unavailable,
  91   invalid_wrong_slot,
  92 }
  93 invalid_type;
  94
  95 extern void print_idecode_invalid
  96   (lf *file, const char *result, invalid_type type);
  97
  98 extern void print_semantic_body
  99   (lf *file,
 100    insn_entry * instruction,
 101    opcode_bits *expanded_bits, insn_opcodes *opcodes);