nkeynes@359: /**
nkeynes@420:  * $Id: gendec.c,v 1.2 2007-10-06 08:48:47 nkeynes Exp $
nkeynes@359:  * 
nkeynes@359:  * Parse the instruction and action files and generate an appropriate
nkeynes@359:  * instruction decoder.
nkeynes@359:  *
nkeynes@359:  * Copyright (c) 2005 Nathan Keynes.
nkeynes@359:  *
nkeynes@359:  * This program is free software; you can redistribute it and/or modify
nkeynes@359:  * it under the terms of the GNU General Public License as published by
nkeynes@359:  * the Free Software Foundation; either version 2 of the License, or
nkeynes@359:  * (at your option) any later version.
nkeynes@359:  *
nkeynes@359:  * This program is distributed in the hope that it will be useful,
nkeynes@359:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
nkeynes@359:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
nkeynes@359:  * GNU General Public License for more details.
nkeynes@359:  */
nkeynes@359: 
nkeynes@359: #include <stdio.h>
nkeynes@359: #include <stdlib.h>
nkeynes@359: #include <string.h>
nkeynes@359: #include <getopt.h>
nkeynes@359: #include <errno.h>
nkeynes@359: #include <ctype.h>
nkeynes@359: #include <glib/gstrfuncs.h>
nkeynes@359: #include <assert.h>
nkeynes@359: #include "tools/gendec.h"
nkeynes@359: 
nkeynes@359: #define DEFAULT_OUT_EXT ".c"
nkeynes@359: 
nkeynes@359: const char *ins_filename = NULL;
nkeynes@359: const char *act_filename = NULL;
nkeynes@359: const char *out_filename = NULL;
nkeynes@359: 
nkeynes@359: #define GEN_SOURCE 1
nkeynes@359: #define GEN_TEMPLATE 2
nkeynes@359: 
nkeynes@359: FILE *ins_file, *act_file, *out_file;
nkeynes@359: 
nkeynes@359: char *option_list = "tmho:";
nkeynes@359: int gen_mode = GEN_SOURCE;
nkeynes@359: struct option longopts[1] = { { NULL, 0, 0, 0 } };
nkeynes@359: 
nkeynes@359: void usage() {
nkeynes@359:     printf( "gendec <instruction-file> <action-file> [ -o <output-file> ]\n" );
nkeynes@359: }
nkeynes@359: 
nkeynes@359: /**
nkeynes@359:  * Find a mask that can be used to split up the given rules
nkeynes@359:  */
nkeynes@359: uint32_t find_mask( struct ruleset *rules, int ruleidx[], int rule_count, 
nkeynes@359: 		    uint32_t input_mask )
nkeynes@359: {
nkeynes@359:     int i;
nkeynes@359:     uint32_t mask = rules->rules[ruleidx[0]]->mask;
nkeynes@359: 
nkeynes@359:     for( i=1; i<rule_count; i++ ) {
nkeynes@359: 	mask = mask & rules->rules[ruleidx[i]]->mask;
nkeynes@359:     }
nkeynes@359: 
nkeynes@359:     assert( (mask & input_mask) == input_mask ); /* input_mask should always be included in the mask */
nkeynes@359: 
nkeynes@359:     return mask & (~input_mask); /* but we don't want to see the input mask again */
nkeynes@359: }
nkeynes@359: 
nkeynes@359: int get_option_count_for_mask( uint32_t mask ) {
nkeynes@359:     int count = 0;
nkeynes@359: 
nkeynes@359:     while( mask ) {
nkeynes@359: 	if( mask&1 ) 
nkeynes@359: 	    count++;
nkeynes@359: 	mask >>= 1;
nkeynes@359:     }
nkeynes@359:     return 1<<count;
nkeynes@359: }
nkeynes@359: 
nkeynes@359: int get_bitshift_for_mask( uint32_t mask ) {
nkeynes@359:     int shift = 0;
nkeynes@359:     while( mask && !(mask&1) ) {
nkeynes@359: 	shift++;
nkeynes@359: 	mask >>= 1;
nkeynes@359:     }
nkeynes@359:     return shift;
nkeynes@359: }
nkeynes@359: 
nkeynes@359: void get_option_values_for_mask( uint32_t *options, 
nkeynes@359: 				      uint32_t mask ) 
nkeynes@359: {
nkeynes@359:     /* This could be a lot smarter. But it's not */
nkeynes@359:     int i;
nkeynes@359:     *options = 0;
nkeynes@359:     for( i=1; i<=mask; i++ ) {
nkeynes@359: 	if( (i & mask) > *options ) {
nkeynes@359: 	    options++;
nkeynes@359: 	    *options = (i&mask);
nkeynes@359: 	}
nkeynes@359:     }
nkeynes@359: }
nkeynes@359: 
nkeynes@420: void fprint_indent( char *action, int depth, FILE *f )
nkeynes@359: {
nkeynes@359:     int spaces = 0, needed = depth*8, i;
nkeynes@359:     char *text = action;
nkeynes@359: 
nkeynes@359:     /* Determine number of spaces in first line of input */
nkeynes@359:     for( i=0; isspace(action[i]); i++ ) {
nkeynes@359: 	if( action[i] == '\n' ) {
nkeynes@359: 	    spaces = 0;
nkeynes@359: 	    text = &action[i+1];
nkeynes@359: 	} else {
nkeynes@359: 	    spaces++;
nkeynes@359: 	}
nkeynes@359:     }
nkeynes@359: 
nkeynes@359:     needed -= spaces;
nkeynes@359:     fprintf( f, "%*c", needed, ' ' );
nkeynes@359:     for( i=0; text[i] != '\0'; i++ ) {
nkeynes@359: 	fputc( text[i], f );
nkeynes@359: 	if( text[i] == '\n' && text[i+1] != '\0' ) {
nkeynes@359: 	    fprintf( f, "%*c", needed, ' ' );
nkeynes@359: 	}
nkeynes@359:     }
nkeynes@359:     if( text[i-1] != '\n' ) {
nkeynes@359: 	fprintf( f, "\n" );
nkeynes@359:     }
nkeynes@359: }
nkeynes@359: 
nkeynes@420: void fprint_action( struct rule *rule, char *action, int depth, FILE *f ) 
nkeynes@359: {
nkeynes@359:     int i;
nkeynes@359:     if( action == NULL ) {
nkeynes@359: 	fprintf( f, "%*cUNIMP(ir); /* %s */\n", depth*8, ' ', rule->format );
nkeynes@359:     } else {
nkeynes@359: 	fprintf( f, "%*c{ /* %s */", depth*8, ' ', rule->format );
nkeynes@359: 	if( rule->operand_count != 0 ) {
nkeynes@359: 	    fprintf( f, "\n%*c", depth*8, ' ' );
nkeynes@359: 	    for( i=0; i<rule->operand_count; i++ ) {
nkeynes@359: 		if( rule->operands[i].is_signed ) {
nkeynes@359: 		    fprintf( f, "int32_t %s = SIGNEXT%d", rule->operands[i].name, rule->operands[i].bit_count );
nkeynes@359: 		} else {
nkeynes@359: 		    fprintf( f, "uint32_t %s = ", rule->operands[i].name );
nkeynes@359: 		}
nkeynes@359: 		if( rule->operands[i].bit_shift == 0 ) {
nkeynes@359: 		    fprintf( f, "(ir&0x%X)", (1<<(rule->operands[i].bit_count))-1 );
nkeynes@359: 		} else {
nkeynes@359: 		    fprintf( f, "((ir>>%d)&0x%X)", rule->operands[i].bit_shift,
nkeynes@359: 			     (1<<(rule->operands[i].bit_count))-1 );
nkeynes@359: 		}
nkeynes@359: 		if( rule->operands[i].left_shift != 0 ) {
nkeynes@359: 		    fprintf( f, "<<%d", rule->operands[i].left_shift );
nkeynes@359: 		}
nkeynes@359: 		fprintf( f, "; " );
nkeynes@359: 	    }
nkeynes@359: 	}
nkeynes@359: 	fputs( "\n", f );
nkeynes@359: 	if( action[0] != '\0' ) {
nkeynes@359: 	    fprint_indent( action, depth, f );
nkeynes@359: 	}
nkeynes@359: 	fprintf( f, "%*c}\n", depth*8, ' ' );
nkeynes@359:     }
nkeynes@359: }
nkeynes@359: 
nkeynes@420: void split_and_generate( struct ruleset *rules, struct actionset *actions, 
nkeynes@359: 			int ruleidx[], int rule_count, int input_mask, 
nkeynes@359: 			int depth, FILE *f ) {
nkeynes@359:     uint32_t mask;
nkeynes@359:     int i,j;
nkeynes@359: 
nkeynes@359:     if( rule_count == 0 ) {
nkeynes@359: 	fprintf( f, "%*cUNDEF(ir);\n", depth*8, ' ' );
nkeynes@359:     } else if( rule_count == 1 ) {
nkeynes@359: 	fprint_action( rules->rules[ruleidx[0]], actions->actions[ruleidx[0]], depth, f );
nkeynes@359:     } else {
nkeynes@359: 
nkeynes@359: 	mask = find_mask(rules, ruleidx, rule_count, input_mask);
nkeynes@359: 	if( mask == 0 ) { /* No matching mask? */
nkeynes@359: 	    fprintf( stderr, "Error: unable to find a valid bitmask (%d rules, %08X input mask)\n", rule_count, input_mask );
nkeynes@359: 	    dump_rulesubset( rules, ruleidx, rule_count, stderr );
nkeynes@420: 	    return;
nkeynes@359: 	}
nkeynes@359: 	
nkeynes@359: 	/* break up the rules into sub-sets, and process each sub-set.
nkeynes@359: 	 * NB: We could do this in one pass at the cost of more complex
nkeynes@359: 	 * data structures. For now though, this keeps it simple
nkeynes@359: 	 */
nkeynes@359: 	int option_count = get_option_count_for_mask( mask );
nkeynes@359: 	uint32_t options[option_count];
nkeynes@359: 	int subruleidx[rule_count];
nkeynes@359: 	int subrule_count;
nkeynes@359: 	int mask_shift = get_bitshift_for_mask( mask );
nkeynes@359: 	int has_empty_options = 0;
nkeynes@359: 	get_option_values_for_mask( options, mask );
nkeynes@359: 	
nkeynes@359: 	if( mask_shift == 0 ) {
nkeynes@359: 	    fprintf( f, "%*cswitch( ir&0x%X ) {\n", depth*8, ' ', mask );
nkeynes@359: 	} else {
nkeynes@359: 	    fprintf( f, "%*cswitch( (ir&0x%X) >> %d ) {\n", depth*8, ' ',
nkeynes@359: 		     mask, mask_shift);
nkeynes@359: 	}
nkeynes@359: 	for( i=0; i<option_count; i++ ) {
nkeynes@359: 	    subrule_count = 0;
nkeynes@359: 	    for( j=0; j<rule_count; j++ ) {
nkeynes@359: 		int match = rules->rules[ruleidx[j]]->bits & mask;
nkeynes@359: 		if( match == options[i] ) {
nkeynes@359: 		    subruleidx[subrule_count++] = ruleidx[j];
nkeynes@359: 		}
nkeynes@359: 	    }
nkeynes@359: 	    if( subrule_count == 0 ) {
nkeynes@359: 		has_empty_options = 1;
nkeynes@359: 	    } else {
nkeynes@359: 		fprintf( f, "%*ccase 0x%X:\n", depth*8+4, ' ', options[i]>>mask_shift );
nkeynes@359: 		split_and_generate( rules, actions, subruleidx, subrule_count,
nkeynes@359: 				    mask|input_mask, depth+1, f );
nkeynes@359: 		fprintf( f, "%*cbreak;\n", depth*8+8, ' ' );
nkeynes@359: 	    }
nkeynes@359: 	}
nkeynes@359: 	if( has_empty_options ) {
nkeynes@359: 	    fprintf( f, "%*cdefault:\n%*cUNDEF();\n%*cbreak;\n",
nkeynes@359: 		     depth*8+4, ' ', depth*8+8, ' ', depth*8 + 8, ' ' );
nkeynes@359: 	}
nkeynes@359: 	fprintf( f, "%*c}\n", depth*8, ' ' );
nkeynes@359:     }
nkeynes@359: }
nkeynes@359: 
nkeynes@359: int generate_decoder( struct ruleset *rules, struct actionset *actions, FILE *f )
nkeynes@359: {
nkeynes@359:     int ruleidx[rules->rule_count];
nkeynes@359:     int i;
nkeynes@359: 
nkeynes@359:     for( i=0; i<rules->rule_count; i++ ) {
nkeynes@359: 	ruleidx[i] = i;
nkeynes@359:     }
nkeynes@359: 
nkeynes@359:     fputs( actions->pretext, f );
nkeynes@359:     
nkeynes@359:     split_and_generate( rules, actions, ruleidx, rules->rule_count, 0, 1, f );
nkeynes@359: 
nkeynes@359:     fputs( actions->posttext, f );
nkeynes@359:     
nkeynes@359:     return 0;
nkeynes@359: }
nkeynes@359: 
nkeynes@359: int generate_template( struct ruleset *rules, struct actionset *actions, FILE *f )
nkeynes@359: {
nkeynes@359:     int i;
nkeynes@359:     fputs( actions->pretext, f );
nkeynes@359:     fputs( "%%\n", f );
nkeynes@359: 
nkeynes@359:     for( i=0; i<rules->rule_count; i++ ) {
nkeynes@359: 	fprintf( f, "%s {: %s :}\n", rules->rules[i]->format, 
nkeynes@359: 		 actions->actions[i] == NULL ? "" : actions->actions[i] );
nkeynes@359:     }
nkeynes@359:     fputs( "%%\n", f );
nkeynes@359:     fputs( actions->posttext, f );
nkeynes@359:     
nkeynes@359:     return 0;
nkeynes@359: }
nkeynes@420: 
nkeynes@420: 
nkeynes@420: int main( int argc, char *argv[] )
nkeynes@420: {
nkeynes@420:     int opt;
nkeynes@420: 
nkeynes@420:     /* Parse the command line */
nkeynes@420:     while( (opt = getopt_long( argc, argv, option_list, longopts, NULL )) != -1 ) {
nkeynes@420:         switch( opt ) {
nkeynes@420: 	case 't':
nkeynes@420: 	    gen_mode = GEN_TEMPLATE;
nkeynes@420: 	    break;
nkeynes@420: 	case 'o':
nkeynes@420: 	    out_filename = optarg;
nkeynes@420: 	    break;
nkeynes@420: 	case 'h':
nkeynes@420: 	    usage();
nkeynes@420: 	    exit(0);
nkeynes@420: 	}
nkeynes@420:     }
nkeynes@420:     if( optind < argc ) {
nkeynes@420: 	ins_filename = argv[optind++];
nkeynes@420:     }
nkeynes@420:     if( optind < argc ) {
nkeynes@420: 	act_filename = argv[optind++];
nkeynes@420:     }
nkeynes@420: 
nkeynes@420:     if( optind < argc || ins_filename == NULL || act_filename == NULL ) {
nkeynes@420: 	usage();
nkeynes@420: 	exit(1);
nkeynes@420:     }
nkeynes@420:     
nkeynes@420:     if( out_filename == NULL ) {
nkeynes@420: 	if( gen_mode == GEN_TEMPLATE ) {
nkeynes@420: 	    out_filename = act_filename;
nkeynes@420: 	} else {
nkeynes@420: 	    char tmp[strlen(act_filename)+1];
nkeynes@420: 	    strcpy( tmp, act_filename);
nkeynes@420: 	    char *c = strrchr( tmp, '.' );
nkeynes@420: 	    if( c != NULL ) {
nkeynes@420: 		*c = '\0';
nkeynes@420: 	    }
nkeynes@420: 	    out_filename = g_strconcat( tmp, DEFAULT_OUT_EXT, NULL );
nkeynes@420: 	}
nkeynes@420:     }
nkeynes@420: 
nkeynes@420:     /* Open the files */
nkeynes@420:     ins_file = fopen( ins_filename, "ro" );
nkeynes@420:     if( ins_file == NULL ) {
nkeynes@420:         fprintf( stderr, "Unable to open '%s' for reading (%s)\n", ins_filename, strerror(errno) );
nkeynes@420: 	exit(2);
nkeynes@420:     }
nkeynes@420: 
nkeynes@420:     act_file = fopen( act_filename, "ro" );
nkeynes@420:     if( act_file == NULL ) {
nkeynes@420:         fprintf( stderr, "Unable to open '%s' for reading (%s)\n", act_filename, strerror(errno) );
nkeynes@420: 	exit(3);
nkeynes@420:     }
nkeynes@420: 	
nkeynes@420:     /* Parse the input */
nkeynes@420:     struct ruleset *rules = parse_ruleset_file( ins_file );
nkeynes@420:     fclose( ins_file );
nkeynes@420:     if( rules == NULL ) {
nkeynes@420: 	exit(5);
nkeynes@420:     }
nkeynes@420: 
nkeynes@420:     struct actionset *actions = parse_action_file( rules, act_file );
nkeynes@420:     fclose( act_file );
nkeynes@420:     if( actions == NULL ) {
nkeynes@420: 	exit(6);
nkeynes@420:     }
nkeynes@420: 
nkeynes@420:     /* Finally write out the results */
nkeynes@420:     out_file = fopen( out_filename, "wo" );
nkeynes@420:     if( out_file == NULL ) {
nkeynes@420:         fprintf( stderr, "Unable to open '%s' for writing (%s)\n", out_filename, strerror(errno) );
nkeynes@420: 	exit(4);
nkeynes@420:     }
nkeynes@420:     
nkeynes@420:     switch( gen_mode ) {
nkeynes@420:     case GEN_SOURCE:
nkeynes@420: 	if( generate_decoder( rules, actions, out_file ) != 0 ) {
nkeynes@420: 	    exit(7);
nkeynes@420: 	}
nkeynes@420: 	break;
nkeynes@420:     case GEN_TEMPLATE:
nkeynes@420: 	if( generate_template( rules, actions, out_file ) != 0 ) {
nkeynes@420: 	    exit(7);
nkeynes@420: 	}
nkeynes@420: 	break;
nkeynes@420:     }
nkeynes@420:     fclose( out_file );
nkeynes@420:     return 0;
nkeynes@420: }