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+/* This file is part of the program psim.
+
+ Copyright (C) 1994-1997, Andrew Cagney <cagney@highland.com.au>
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+ */
+
+
+/* Creates the files semantics.[hc].
+
+ The generated file semantics contains functions that implement the
+ operations required to model a single target processor instruction.
+
+ Several different variations on the semantics file can be created:
+
+ o uncached
+
+ No instruction cache exists. The semantic function
+ needs to generate any required values locally.
+
+ o cached - separate cracker and semantic
+
+ Two independant functions are created. Firstly the
+ function that cracks an instruction entering it into a
+ cache and secondly the semantic function propper that
+ uses the cache.
+
+ o cached - semantic + cracking semantic
+
+ The function that cracks the instruction and enters
+ all values into the cache also contains a copy of the
+ semantic code (avoiding the need to call both the
+ cracker and the semantic function when there is a
+ cache miss).
+
+ For each of these general forms, several refinements can occure:
+
+ o do/don't duplicate/expand semantic functions
+
+ As a consequence of decoding an instruction, the
+ decoder, as part of its table may have effectivly made
+ certain of the variable fields in an instruction
+ constant. Separate functions for each of the
+ alternative values for what would have been treated as
+ a variable part can be created.
+
+ o use cache struct directly.
+
+ When a cracking cache is present, the semantic
+ functions can be generated to either hold intermediate
+ cache values in local variables or always refer to the
+ contents of the cache directly. */
+
+
+
+
+
+
+extern void print_semantic_declaration
+(lf *file,
+ insn_entry *insn,
+ opcode_bits *bits,
+ insn_opcodes *opcodes,
+ int nr_prefetched_words);
+
+extern void print_semantic_definition
+(lf *file,
+ insn_entry *insn,
+ opcode_bits *bits,
+ insn_opcodes *opcodes,
+ cache_entry *cache_rules,
+ int nr_prefetched_words);
+
+
+typedef enum {
+ invalid_illegal,
+ invalid_fp_unavailable,
+ invalid_wrong_slot,
+} invalid_type;
+
+extern void print_idecode_invalid
+(lf *file,
+ const char *result,
+ invalid_type type);
+
+extern void print_semantic_body
+(lf *file,
+ insn_entry *instruction,
+ opcode_bits *expanded_bits,
+ insn_opcodes *opcodes);
+