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[/] [openrisc/] [trunk/] [gnu-src/] [gdb-6.8/] [sim/] [ppc/] [gen-semantics.h] - Blame information for rev 258

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1 24 jeremybenn
/*  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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