mirror of
https://sourceware.org/git/binutils-gdb.git
synced 2024-12-03 04:12:10 +08:00
82 lines
2.6 KiB
C
82 lines
2.6 KiB
C
|
/* This file is part of the program psim.
|
||
|
|
||
|
Copyright (C) 1994-1995, 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 insn_handler print_semantic_declaration;
|
||
|
extern insn_handler print_semantic_definition;
|
||
|
|
||
|
extern void print_idecode_illegal
|
||
|
(lf *file,
|
||
|
const char *result);
|
||
|
|
||
|
extern void print_semantic_body
|
||
|
(lf *file,
|
||
|
insn *instruction,
|
||
|
insn_bits *expanded_bits,
|
||
|
opcode_field *opcodes);
|
||
|
|