82 lines
2.6 KiB
C
82 lines
2.6 KiB
C
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/* This file is part of the program psim.
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Copyright (C) 1994-1995, Andrew Cagney <cagney@highland.com.au>
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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*/
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/* Creates the files semantics.[hc].
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The generated file semantics contains functions that implement the
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operations required to model a single target processor instruction.
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Several different variations on the semantics file can be created:
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o uncached
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No instruction cache exists. The semantic function
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needs to generate any required values locally.
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o cached - separate cracker and semantic
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Two independant functions are created. Firstly the
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function that cracks an instruction entering it into a
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cache and secondly the semantic function propper that
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uses the cache.
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o cached - semantic + cracking semantic
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The function that cracks the instruction and enters
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all values into the cache also contains a copy of the
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semantic code (avoiding the need to call both the
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cracker and the semantic function when there is a
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cache miss).
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For each of these general forms, several refinements can occure:
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o do/don't duplicate/expand semantic functions
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As a consequence of decoding an instruction, the
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decoder, as part of its table may have effectivly made
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certain of the variable fields in an instruction
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constant. Separate functions for each of the
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alternative values for what would have been treated as
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a variable part can be created.
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o use cache struct directly.
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When a cracking cache is present, the semantic
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functions can be generated to either hold intermediate
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cache values in local variables or always refer to the
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contents of the cache directly. */
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extern insn_handler print_semantic_declaration;
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extern insn_handler print_semantic_definition;
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extern void print_idecode_illegal
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(lf *file,
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const char *result);
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extern void print_semantic_body
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(lf *file,
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insn *instruction,
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insn_bits *expanded_bits,
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opcode_field *opcodes);
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