1 /*
2  * Aic7xxx SCSI host adapter firmware assembler
3  *
4  * Copyright (c) 1997, 1998, 2000, 2001 Justin T. Gibbs.
5  * Copyright (c) 2001, 2002 Adaptec Inc.
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions, and the following disclaimer,
13  *    without modification.
14  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
15  *    substantially similar to the "NO WARRANTY" disclaimer below
16  *    ("Disclaimer") and any redistribution must be conditioned upon
17  *    including a substantially similar Disclaimer requirement for further
18  *    binary redistribution.
19  * 3. Neither the names of the above-listed copyright holders nor the names
20  *    of any contributors may be used to endorse or promote products derived
21  *    from this software without specific prior written permission.
22  *
23  * Alternatively, this software may be distributed under the terms of the
24  * GNU General Public License ("GPL") version 2 as published by the Free
25  * Software Foundation.
26  *
27  * NO WARRANTY
28  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
29  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
30  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
31  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
32  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
36  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
37  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
38  * POSSIBILITY OF SUCH DAMAGES.
39  *
40  * $Id: //depot/aic7xxx/aic7xxx/aicasm/aicasm.c#23 $
41  *
42  * $FreeBSD$
43  */
44 #include <sys/types.h>
45 #include <sys/mman.h>
46 
47 #include <ctype.h>
48 #include <inttypes.h>
49 #include <regex.h>
50 #include <stdio.h>
51 #include <stdlib.h>
52 #include <string.h>
53 #include <sysexits.h>
54 #include <unistd.h>
55 
56 #if linux
57 #include <endian.h>
58 #else
59 #include <machine/endian.h>
60 #endif
61 
62 #include "aicasm.h"
63 #include "aicasm_symbol.h"
64 #include "aicasm_insformat.h"
65 
66 typedef struct patch {
67 	STAILQ_ENTRY(patch) links;
68 	int		patch_func;
69 	u_int		begin;
70 	u_int		skip_instr;
71 	u_int		skip_patch;
72 } patch_t;
73 
74 STAILQ_HEAD(patch_list, patch) patches;
75 
76 static void usage(void);
77 static void back_patch(void);
78 static void output_code(void);
79 static void output_listing(char *ifilename);
80 static void dump_scope(scope_t *scope);
81 static void emit_patch(scope_t *scope, int patch);
82 static int check_patch(patch_t **start_patch, int start_instr,
83 		       int *skip_addr, int *func_vals);
84 
85 struct path_list search_path;
86 int includes_search_curdir;
87 char *appname;
88 char *stock_include_file;
89 FILE *ofile;
90 char *ofilename;
91 char *regfilename;
92 FILE *regfile;
93 char *listfilename;
94 FILE *listfile;
95 char *regdiagfilename;
96 FILE *regdiagfile;
97 int   src_mode;
98 int   dst_mode;
99 
100 static STAILQ_HEAD(,instruction) seq_program;
101 struct cs_tailq cs_tailq;
102 struct scope_list scope_stack;
103 symlist_t patch_functions;
104 
105 #if DEBUG
106 extern int yy_flex_debug;
107 extern int mm_flex_debug;
108 extern int yydebug;
109 extern int mmdebug;
110 #endif
111 extern FILE *yyin;
112 extern int yyparse(void);
113 
114 int main(int argc, char *argv[]);
115 
116 int
117 main(int argc, char *argv[])
118 {
119 	extern char *optarg;
120 	extern int optind;
121 	int  ch;
122 	int  retval;
123 	char *inputfilename;
124 	scope_t *sentinal;
125 
126 	STAILQ_INIT(&patches);
127 	SLIST_INIT(&search_path);
128 	STAILQ_INIT(&seq_program);
129 	TAILQ_INIT(&cs_tailq);
130 	SLIST_INIT(&scope_stack);
131 
132 	/* Set Sentinal scope node */
133 	sentinal = scope_alloc();
134 	sentinal->type = SCOPE_ROOT;
135 
136 	includes_search_curdir = 1;
137 	appname = *argv;
138 	regfile = NULL;
139 	listfile = NULL;
140 #if DEBUG
141 	yy_flex_debug = 0;
142 	mm_flex_debug = 0;
143 	yydebug = 0;
144 	mmdebug = 0;
145 #endif
146 	while ((ch = getopt(argc, argv, "d:i:l:n:o:p:r:I:")) != -1) {
147 		switch(ch) {
148 		case 'd':
149 #if DEBUG
150 			if (strcmp(optarg, "s") == 0) {
151 				yy_flex_debug = 1;
152 				mm_flex_debug = 1;
153 			} else if (strcmp(optarg, "p") == 0) {
154 				yydebug = 1;
155 				mmdebug = 1;
156 			} else {
157 				fprintf(stderr, "%s: -d Requires either an "
158 					"'s' or 'p' argument\n", appname);
159 				usage();
160 			}
161 #else
162 			stop("-d: Assembler not built with debugging "
163 			     "information", EX_SOFTWARE);
164 #endif
165 			break;
166 		case 'i':
167 			stock_include_file = optarg;
168 			break;
169 		case 'l':
170 			/* Create a program listing */
171 			if ((listfile = fopen(optarg, "w")) == NULL) {
172 				perror(optarg);
173 				stop(NULL, EX_CANTCREAT);
174 			}
175 			listfilename = optarg;
176 			break;
177 		case 'n':
178 			/* Don't complain about the -nostdinc directrive */
179 			if (strcmp(optarg, "ostdinc")) {
180 				fprintf(stderr, "%s: Unknown option -%c%s\n",
181 					appname, ch, optarg);
182 				usage();
183 				/* NOTREACHED */
184 			}
185 			break;
186 		case 'o':
187 			if ((ofile = fopen(optarg, "w")) == NULL) {
188 				perror(optarg);
189 				stop(NULL, EX_CANTCREAT);
190 			}
191 			ofilename = optarg;
192 			break;
193 		case 'p':
194 			/* Create Register Diagnostic "printing" Functions */
195 			if ((regdiagfile = fopen(optarg, "w")) == NULL) {
196 				perror(optarg);
197 				stop(NULL, EX_CANTCREAT);
198 			}
199 			regdiagfilename = optarg;
200 			break;
201 		case 'r':
202 			if ((regfile = fopen(optarg, "w")) == NULL) {
203 				perror(optarg);
204 				stop(NULL, EX_CANTCREAT);
205 			}
206 			regfilename = optarg;
207 			break;
208 		case 'I':
209 		{
210 			path_entry_t include_dir;
211 
212 			if (strcmp(optarg, "-") == 0) {
213 				if (includes_search_curdir == 0) {
214 					fprintf(stderr, "%s: Warning - '-I-' "
215 							"specified multiple "
216 							"times\n", appname);
217 				}
218 				includes_search_curdir = 0;
219 				for (include_dir = SLIST_FIRST(&search_path);
220 				     include_dir != NULL;
221 				     include_dir = SLIST_NEXT(include_dir,
222 							      links))
223 					/*
224 					 * All entries before a '-I-' only
225 					 * apply to includes specified with
226 					 * quotes instead of "<>".
227 					 */
228 					include_dir->quoted_includes_only = 1;
229 			} else {
230 				include_dir =
231 				    (path_entry_t)malloc(sizeof(*include_dir));
232 				if (include_dir == NULL) {
233 					perror(optarg);
234 					stop(NULL, EX_OSERR);
235 				}
236 				include_dir->directory = strdup(optarg);
237 				if (include_dir->directory == NULL) {
238 					perror(optarg);
239 					stop(NULL, EX_OSERR);
240 				}
241 				include_dir->quoted_includes_only = 0;
242 				SLIST_INSERT_HEAD(&search_path, include_dir,
243 						  links);
244 			}
245 			break;
246 		}
247 		case '?':
248 		default:
249 			usage();
250 			/* NOTREACHED */
251 		}
252 	}
253 	argc -= optind;
254 	argv += optind;
255 
256 	if (argc != 1) {
257 		fprintf(stderr, "%s: No input file specified\n", appname);
258 		usage();
259 		/* NOTREACHED */
260 	}
261 
262 	if (regdiagfile != NULL
263 	 && (regfile == NULL || stock_include_file == NULL)) {
264 		fprintf(stderr,
265 			"%s: The -p option requires the -r and -i options.\n",
266 			appname);
267 		usage();
268 		/* NOTREACHED */
269 	}
270 	symtable_open();
271 	inputfilename = *argv;
272 	include_file(*argv, SOURCE_FILE);
273 	retval = yyparse();
274 	if (retval == 0) {
275 		if (SLIST_FIRST(&scope_stack) == NULL
276 		 || SLIST_FIRST(&scope_stack)->type != SCOPE_ROOT) {
277 			stop("Unterminated conditional expression", EX_DATAERR);
278 			/* NOTREACHED */
279 		}
280 
281 		/* Process outmost scope */
282 		process_scope(SLIST_FIRST(&scope_stack));
283 		/*
284 		 * Decend the tree of scopes and insert/emit
285 		 * patches as appropriate.  We perform a depth first
286 		 * tranversal, recursively handling each scope.
287 		 */
288 		/* start at the root scope */
289 		dump_scope(SLIST_FIRST(&scope_stack));
290 
291 		/* Patch up forward jump addresses */
292 		back_patch();
293 
294 		if (ofile != NULL)
295 			output_code();
296 		if (regfile != NULL)
297 			symtable_dump(regfile, regdiagfile);
298 		if (listfile != NULL)
299 			output_listing(inputfilename);
300 	}
301 
302 	stop(NULL, 0);
303 	/* NOTREACHED */
304 	return (0);
305 }
306 
307 static void
308 usage()
309 {
310 
311 	(void)fprintf(stderr,
312 "usage: %-16s [-nostdinc] [-I-] [-I directory] [-o output_file]\n"
313 "	[-r register_output_file [-p register_diag_file -i includefile]]\n"
314 "	[-l program_list_file]\n"
315 "	input_file\n", appname);
316 	exit(EX_USAGE);
317 }
318 
319 static void
320 back_patch()
321 {
322 	struct instruction *cur_instr;
323 
324 	for (cur_instr = STAILQ_FIRST(&seq_program);
325 	     cur_instr != NULL;
326 	     cur_instr = STAILQ_NEXT(cur_instr, links)) {
327 		if (cur_instr->patch_label != NULL) {
328 			struct ins_format3 *f3_instr;
329 			u_int address;
330 
331 			if (cur_instr->patch_label->type != LABEL) {
332 				char buf[255];
333 
334 				snprintf(buf, sizeof(buf),
335 					 "Undefined label %s",
336 					 cur_instr->patch_label->name);
337 				stop(buf, EX_DATAERR);
338 				/* NOTREACHED */
339 			}
340 			f3_instr = &cur_instr->format.format3;
341 			address = f3_instr->address;
342 			address += cur_instr->patch_label->info.linfo->address;
343 			f3_instr->address = address;
344 		}
345 	}
346 }
347 
348 static void
349 output_code()
350 {
351 	struct instruction *cur_instr;
352 	patch_t *cur_patch;
353 	critical_section_t *cs;
354 	symbol_node_t *cur_node;
355 	int instrcount;
356 
357 	instrcount = 0;
358 	fprintf(ofile,
359 "/*\n"
360 " * DO NOT EDIT - This file is automatically generated\n"
361 " *		 from the following source files:\n"
362 " *\n"
363 "%s */\n", versions);
364 
365 	fprintf(ofile, "static const uint8_t seqprog[] = {\n");
366 	for (cur_instr = STAILQ_FIRST(&seq_program);
367 	     cur_instr != NULL;
368 	     cur_instr = STAILQ_NEXT(cur_instr, links)) {
369 
370 		fprintf(ofile, "%s\t0x%02x, 0x%02x, 0x%02x, 0x%02x",
371 			cur_instr == STAILQ_FIRST(&seq_program) ? "" : ",\n",
372 #ifdef __LITTLE_ENDIAN
373 			cur_instr->format.bytes[0],
374 			cur_instr->format.bytes[1],
375 			cur_instr->format.bytes[2],
376 			cur_instr->format.bytes[3]);
377 #else
378 			cur_instr->format.bytes[3],
379 			cur_instr->format.bytes[2],
380 			cur_instr->format.bytes[1],
381 			cur_instr->format.bytes[0]);
382 #endif
383 		instrcount++;
384 	}
385 	fprintf(ofile, "\n};\n\n");
386 
387 	if (patch_arg_list == NULL)
388 		stop("Patch argument list not defined",
389 		     EX_DATAERR);
390 
391 	/*
392 	 *  Output patch information.  Patch functions first.
393 	 */
394 	fprintf(ofile,
395 "typedef int %spatch_func_t (%s);\n", prefix, patch_arg_list);
396 
397 	for (cur_node = SLIST_FIRST(&patch_functions);
398 	     cur_node != NULL;
399 	     cur_node = SLIST_NEXT(cur_node,links)) {
400 		fprintf(ofile,
401 "static %spatch_func_t %spatch%d_func;\n"
402 "\n"
403 "static int\n"
404 "%spatch%d_func(%s)\n"
405 "{\n"
406 "	return (%s);\n"
407 "}\n\n",
408 			prefix,
409 			prefix,
410 			cur_node->symbol->info.condinfo->func_num,
411 			prefix,
412 			cur_node->symbol->info.condinfo->func_num,
413 			patch_arg_list,
414 			cur_node->symbol->name);
415 	}
416 
417 	fprintf(ofile,
418 "static const struct patch {\n"
419 "	%spatch_func_t		*patch_func;\n"
420 "	uint32_t		 begin		:10,\n"
421 "				 skip_instr	:10,\n"
422 "				 skip_patch	:12;\n"
423 "} patches[] = {\n", prefix);
424 
425 	for (cur_patch = STAILQ_FIRST(&patches);
426 	     cur_patch != NULL;
427 	     cur_patch = STAILQ_NEXT(cur_patch,links)) {
428 		fprintf(ofile, "%s\t{ %spatch%d_func, %d, %d, %d }",
429 			cur_patch == STAILQ_FIRST(&patches) ? "" : ",\n",
430 			prefix,
431 			cur_patch->patch_func, cur_patch->begin,
432 			cur_patch->skip_instr, cur_patch->skip_patch);
433 	}
434 
435 	fprintf(ofile, "\n};\n\n");
436 
437 	fprintf(ofile,
438 "static const struct cs {\n"
439 "	uint16_t	begin;\n"
440 "	uint16_t	end;\n"
441 "} critical_sections[] = {\n");
442 
443 	for (cs = TAILQ_FIRST(&cs_tailq);
444 	     cs != NULL;
445 	     cs = TAILQ_NEXT(cs, links)) {
446 		fprintf(ofile, "%s\t{ %d, %d }",
447 			cs == TAILQ_FIRST(&cs_tailq) ? "" : ",\n",
448 			cs->begin_addr, cs->end_addr);
449 	}
450 
451 	fprintf(ofile, "\n};\n\n");
452 
453 	fprintf(ofile,
454 	"#define NUM_CRITICAL_SECTIONS ARRAY_SIZE(critical_sections)\n");
455 
456 	fprintf(stderr, "%s: %d instructions used\n", appname, instrcount);
457 }
458 
459 static void
460 dump_scope(scope_t *scope)
461 {
462 	scope_t *cur_scope;
463 
464 	/*
465 	 * Emit the first patch for this scope
466 	 */
467 	emit_patch(scope, 0);
468 
469 	/*
470 	 * Dump each scope within this one.
471 	 */
472 	cur_scope = TAILQ_FIRST(&scope->inner_scope);
473 
474 	while (cur_scope != NULL) {
475 
476 		dump_scope(cur_scope);
477 
478 		cur_scope = TAILQ_NEXT(cur_scope, scope_links);
479 	}
480 
481 	/*
482 	 * Emit the second, closing, patch for this scope
483 	 */
484 	emit_patch(scope, 1);
485 }
486 
487 void
488 emit_patch(scope_t *scope, int patch)
489 {
490 	patch_info_t *pinfo;
491 	patch_t *new_patch;
492 
493 	pinfo = &scope->patches[patch];
494 
495 	if (pinfo->skip_instr == 0)
496 		/* No-Op patch */
497 		return;
498 
499 	new_patch = (patch_t *)malloc(sizeof(*new_patch));
500 
501 	if (new_patch == NULL)
502 		stop("Could not malloc patch structure", EX_OSERR);
503 
504 	memset(new_patch, 0, sizeof(*new_patch));
505 
506 	if (patch == 0) {
507 		new_patch->patch_func = scope->func_num;
508 		new_patch->begin = scope->begin_addr;
509 	} else {
510 		new_patch->patch_func = 0;
511 		new_patch->begin = scope->end_addr;
512 	}
513 	new_patch->skip_instr = pinfo->skip_instr;
514 	new_patch->skip_patch = pinfo->skip_patch;
515 	STAILQ_INSERT_TAIL(&patches, new_patch, links);
516 }
517 
518 void
519 output_listing(char *ifilename)
520 {
521 	char buf[1024];
522 	FILE *ifile;
523 	struct instruction *cur_instr;
524 	patch_t *cur_patch;
525 	symbol_node_t *cur_func;
526 	int *func_values;
527 	int instrcount;
528 	int instrptr;
529 	int line;
530 	int func_count;
531 	int skip_addr;
532 
533 	instrcount = 0;
534 	instrptr = 0;
535 	line = 1;
536 	skip_addr = 0;
537 	if ((ifile = fopen(ifilename, "r")) == NULL) {
538 		perror(ifilename);
539 		stop(NULL, EX_DATAERR);
540 	}
541 
542 	/*
543 	 * Determine which options to apply to this listing.
544 	 */
545 	for (func_count = 0, cur_func = SLIST_FIRST(&patch_functions);
546 	    cur_func != NULL;
547 	    cur_func = SLIST_NEXT(cur_func, links))
548 		func_count++;
549 
550 	func_values = NULL;
551 	if (func_count != 0) {
552 		func_values = (int *)malloc(func_count * sizeof(int));
553 
554 		if (func_values == NULL)
555 			stop("Could not malloc", EX_OSERR);
556 
557 		func_values[0] = 0; /* FALSE func */
558 		func_count--;
559 
560 		/*
561 		 * Ask the user to fill in the return values for
562 		 * the rest of the functions.
563 		 */
564 
565 
566 		for (cur_func = SLIST_FIRST(&patch_functions);
567 		     cur_func != NULL && SLIST_NEXT(cur_func, links) != NULL;
568 		     cur_func = SLIST_NEXT(cur_func, links), func_count--) {
569 			int input;
570 
571 			fprintf(stdout, "\n(%s)\n", cur_func->symbol->name);
572 			fprintf(stdout,
573 				"Enter the return value for "
574 				"this expression[T/F]:");
575 
576 			while (1) {
577 
578 				input = getchar();
579 				input = toupper(input);
580 
581 				if (input == 'T') {
582 					func_values[func_count] = 1;
583 					break;
584 				} else if (input == 'F') {
585 					func_values[func_count] = 0;
586 					break;
587 				}
588 			}
589 			if (isatty(fileno(stdin)) == 0)
590 				putchar(input);
591 		}
592 		fprintf(stdout, "\nThanks!\n");
593 	}
594 
595 	/* Now output the listing */
596 	cur_patch = STAILQ_FIRST(&patches);
597 	for (cur_instr = STAILQ_FIRST(&seq_program);
598 	     cur_instr != NULL;
599 	     cur_instr = STAILQ_NEXT(cur_instr, links), instrcount++) {
600 
601 		if (check_patch(&cur_patch, instrcount,
602 				&skip_addr, func_values) == 0) {
603 			/* Don't count this instruction as it is in a patch
604 			 * that was removed.
605 			 */
606                         continue;
607 		}
608 
609 		while (line < cur_instr->srcline) {
610 			fgets(buf, sizeof(buf), ifile);
611 				fprintf(listfile, "             \t%s", buf);
612 				line++;
613 		}
614 		fprintf(listfile, "%04x %02x%02x%02x%02x", instrptr,
615 #ifdef __LITTLE_ENDIAN
616 			cur_instr->format.bytes[0],
617 			cur_instr->format.bytes[1],
618 			cur_instr->format.bytes[2],
619 			cur_instr->format.bytes[3]);
620 #else
621 			cur_instr->format.bytes[3],
622 			cur_instr->format.bytes[2],
623 			cur_instr->format.bytes[1],
624 			cur_instr->format.bytes[0]);
625 #endif
626 		/*
627 		 * Macro expansions can cause several instructions
628 		 * to be output for a single source line.  Only
629 		 * advance the line once in these cases.
630 		 */
631 		if (line == cur_instr->srcline) {
632 			fgets(buf, sizeof(buf), ifile);
633 			fprintf(listfile, "\t%s", buf);
634 			line++;
635 		} else {
636 			fprintf(listfile, "\n");
637 		}
638 		instrptr++;
639 	}
640 	/* Dump the remainder of the file */
641 	while(fgets(buf, sizeof(buf), ifile) != NULL)
642 		fprintf(listfile, "             %s", buf);
643 
644 	fclose(ifile);
645 }
646 
647 static int
648 check_patch(patch_t **start_patch, int start_instr,
649 	    int *skip_addr, int *func_vals)
650 {
651 	patch_t *cur_patch;
652 
653 	cur_patch = *start_patch;
654 
655 	while (cur_patch != NULL && start_instr == cur_patch->begin) {
656 		if (func_vals[cur_patch->patch_func] == 0) {
657 			int skip;
658 
659 			/* Start rejecting code */
660 			*skip_addr = start_instr + cur_patch->skip_instr;
661 			for (skip = cur_patch->skip_patch;
662 			     skip > 0 && cur_patch != NULL;
663 			     skip--)
664 				cur_patch = STAILQ_NEXT(cur_patch, links);
665 		} else {
666 			/* Accepted this patch.  Advance to the next
667 			 * one and wait for our intruction pointer to
668 			 * hit this point.
669 			 */
670 			cur_patch = STAILQ_NEXT(cur_patch, links);
671 		}
672 	}
673 
674 	*start_patch = cur_patch;
675 	if (start_instr < *skip_addr)
676 		/* Still skipping */
677 		return (0);
678 
679 	return (1);
680 }
681 
682 /*
683  * Print out error information if appropriate, and clean up before
684  * terminating the program.
685  */
686 void
687 stop(const char *string, int err_code)
688 {
689 	if (string != NULL) {
690 		fprintf(stderr, "%s: ", appname);
691 		if (yyfilename != NULL) {
692 			fprintf(stderr, "Stopped at file %s, line %d - ",
693 				yyfilename, yylineno);
694 		}
695 		fprintf(stderr, "%s\n", string);
696 	}
697 
698 	if (ofile != NULL) {
699 		fclose(ofile);
700 		if (err_code != 0) {
701 			fprintf(stderr, "%s: Removing %s due to error\n",
702 				appname, ofilename);
703 			unlink(ofilename);
704 		}
705 	}
706 
707 	if (regfile != NULL) {
708 		fclose(regfile);
709 		if (err_code != 0) {
710 			fprintf(stderr, "%s: Removing %s due to error\n",
711 				appname, regfilename);
712 			unlink(regfilename);
713 		}
714 	}
715 
716 	if (listfile != NULL) {
717 		fclose(listfile);
718 		if (err_code != 0) {
719 			fprintf(stderr, "%s: Removing %s due to error\n",
720 				appname, listfilename);
721 			unlink(listfilename);
722 		}
723 	}
724 
725 	symlist_free(&patch_functions);
726 	symtable_close();
727 
728 	exit(err_code);
729 }
730 
731 struct instruction *
732 seq_alloc()
733 {
734 	struct instruction *new_instr;
735 
736 	new_instr = (struct instruction *)malloc(sizeof(struct instruction));
737 	if (new_instr == NULL)
738 		stop("Unable to malloc instruction object", EX_SOFTWARE);
739 	memset(new_instr, 0, sizeof(*new_instr));
740 	STAILQ_INSERT_TAIL(&seq_program, new_instr, links);
741 	new_instr->srcline = yylineno;
742 	return new_instr;
743 }
744 
745 critical_section_t *
746 cs_alloc()
747 {
748 	critical_section_t *new_cs;
749 
750 	new_cs= (critical_section_t *)malloc(sizeof(critical_section_t));
751 	if (new_cs == NULL)
752 		stop("Unable to malloc critical_section object", EX_SOFTWARE);
753 	memset(new_cs, 0, sizeof(*new_cs));
754 
755 	TAILQ_INSERT_TAIL(&cs_tailq, new_cs, links);
756 	return new_cs;
757 }
758 
759 scope_t *
760 scope_alloc()
761 {
762 	scope_t *new_scope;
763 
764 	new_scope = (scope_t *)malloc(sizeof(scope_t));
765 	if (new_scope == NULL)
766 		stop("Unable to malloc scope object", EX_SOFTWARE);
767 	memset(new_scope, 0, sizeof(*new_scope));
768 	TAILQ_INIT(&new_scope->inner_scope);
769 
770 	if (SLIST_FIRST(&scope_stack) != NULL) {
771 		TAILQ_INSERT_TAIL(&SLIST_FIRST(&scope_stack)->inner_scope,
772 				  new_scope, scope_links);
773 	}
774 	/* This patch is now the current scope */
775 	SLIST_INSERT_HEAD(&scope_stack, new_scope, scope_stack_links);
776 	return new_scope;
777 }
778 
779 void
780 process_scope(scope_t *scope)
781 {
782 	/*
783 	 * We are "leaving" this scope.  We should now have
784 	 * enough information to process the lists of scopes
785 	 * we encapsulate.
786 	 */
787 	scope_t *cur_scope;
788 	u_int skip_patch_count;
789 	u_int skip_instr_count;
790 
791 	cur_scope = TAILQ_LAST(&scope->inner_scope, scope_tailq);
792 	skip_patch_count = 0;
793 	skip_instr_count = 0;
794 	while (cur_scope != NULL) {
795 		u_int patch0_patch_skip;
796 
797 		patch0_patch_skip = 0;
798 		switch (cur_scope->type) {
799 		case SCOPE_IF:
800 		case SCOPE_ELSE_IF:
801 			if (skip_instr_count != 0) {
802 				/* Create a tail patch */
803 				patch0_patch_skip++;
804 				cur_scope->patches[1].skip_patch =
805 				    skip_patch_count + 1;
806 				cur_scope->patches[1].skip_instr =
807 				    skip_instr_count;
808 			}
809 
810 			/* Count Head patch */
811 			patch0_patch_skip++;
812 
813 			/* Count any patches contained in our inner scope */
814 			patch0_patch_skip += cur_scope->inner_scope_patches;
815 
816 			cur_scope->patches[0].skip_patch = patch0_patch_skip;
817 			cur_scope->patches[0].skip_instr =
818 			    cur_scope->end_addr - cur_scope->begin_addr;
819 
820 			skip_instr_count += cur_scope->patches[0].skip_instr;
821 
822 			skip_patch_count += patch0_patch_skip;
823 			if (cur_scope->type == SCOPE_IF) {
824 				scope->inner_scope_patches += skip_patch_count;
825 				skip_patch_count = 0;
826 			        skip_instr_count = 0;
827 			}
828 			break;
829 		case SCOPE_ELSE:
830 			/* Count any patches contained in our innter scope */
831 			skip_patch_count += cur_scope->inner_scope_patches;
832 
833 			skip_instr_count += cur_scope->end_addr
834 					  - cur_scope->begin_addr;
835 			break;
836 		case SCOPE_ROOT:
837 			stop("Unexpected scope type encountered", EX_SOFTWARE);
838 			/* NOTREACHED */
839 		}
840 
841 		cur_scope = TAILQ_PREV(cur_scope, scope_tailq, scope_links);
842 	}
843 }
844