xref: /csrg-svn/old/as.vax/asmain.c (revision 638)
1 /* Copyright (c) 1980 Regents of the University of California */
2 static	char sccsid[] = "@(#)asmain.c 4.4 08/16/80";
3 #include <stdio.h>
4 #include <ctype.h>
5 #include <signal.h>
6 
7 #include "as.h"
8 #include "assyms.h"
9 #include "asexpr.h"
10 #include "asscan.h"
11 
12 #ifdef UNIX
13 #define	unix_lang_name "VAX/UNIX Assembler Vasmain.c"
14 #endif
15 
16 #ifdef VMS
17 #define vms_lang_name "VAX/VMS C Assembler V1.00"
18 #endif VMS
19 
20 /*
21  *	variables to manage reading the assembly source files
22  */
23 char	*dotsname;	/*the current file name; managed by the parser*/
24 int	lineno;		/*current line number; managed by the parser*/
25 char	*innames[32];	/*names of the files being assembled*/
26 int	ninfiles;	/*how many interesting files there are*/
27 /*
28  *	Flags settable from the argv process argument list
29  */
30 int	silent = 0;	/*don't complain about any errors*/
31 int	savelabels = 0;	/*write the labels to the a.out file*/
32 int 	d124 = 4;	/*default allocate 4 bytes for unknown pointers*/
33 int	anyerrs = 0;	/*no errors yet*/
34 int	orgwarn = 0;	/*Bad origins*/
35 int	passno = 1;	/* current pass*/
36 int	jxxxJUMP = 0;	/* in jxxxes that branch too far, use jmp instead of brw */
37 int	readonlydata = 0;	/* initialzed data -> text space */
38 
39 #ifdef DEBUG
40 int 	debug = 0;
41 int	toktrace = 0;
42 #endif
43 
44 int	useVM =		/*put the temp file in virtual memory*/
45 #ifdef VMS
46 	1;		/*VMS has virtual memory (duh)*/
47 #endif VMS
48 #ifdef UNIX
49  	0;
50 #endif
51 
52 char	*endcore;	/*where to get more symbol space*/
53 
54 /*
55  *	Managers of the a.out file.
56  */
57 struct	exec	hdr;
58 #define	MAGIC	0407
59 u_long	tsize;		/* total text size */
60 u_long	dsize;		/* total data size */
61 u_long	datbase;	/* base of the data segment */
62 u_long	trsize;		/* total text relocation size */
63 u_long	drsize;		/* total data relocation size */
64 
65 /*
66  *	Information about the current segment is accumulated in
67  *	usedot; the most important information stored is the
68  *	accumulated size of each of the text and data segments
69  *
70  *	dotp points to the correct usedot expression for the current segment
71  */
72 struct	exp	usedot[NLOC+NLOC];	/* info about all segments */
73 struct	exp	*dotp;			/* data/text location pointer */
74 /*
75  *	The inter pass temporary file is opened and closed by stdio, but
76  *	is written to using direct read/write, as the temporary file
77  *	is composed of buffers exactly BUFSIZ long.
78  */
79 FILE	*tmpfil;			/* interpass communication file */
80 /*
81  *	a.out is created during the second pass.
82  *	It is opened by stdio, but is filled with the parallel
83  *	block I/O library
84  */
85 char	*outfile = "a.out";
86 FILE	*a_out_file;
87 off_t	a_out_off;			/* cumulative offsets for segments */
88 /*
89  *	The logical files containing the assembled data for each of
90  *	the text and data segments are
91  *	managed by the parallel block I/O library.
92  *	a.out is logically opened in many places at once to
93  *	receive the assembled data from the various segments as
94  *	it all trickles in, but is physically opened only once
95  *	to minimize file overhead.
96  */
97 BFILE	*usefile[NLOC+NLOC];		/* text/data files */
98 BFILE	*txtfil;			/* current text/data file */
99 /*
100  *	Relocation information is accumulated seperately for each
101  *	segment.  This is required by the old loader (from BTL),
102  *	but not by the new loader (Bill Joy).
103  *
104  *	However, the size of the relocation information can not be computed
105  *	during or after the 1st pass because the ''absoluteness' of values
106  *	is unknown until all locally declared symbols have been seen.
107  *	Thus, the size of the relocation information is only
108  *	known after the second pass is finished.
109  *	This obviates the use of the block I/O
110  *	library, which requires knowing the exact offsets in a.out.
111  *
112  *	So, we save the relocation information internally (we don't
113  *	go to internal files to minimize overhead).
114  *
115  *	Empirically, we studied 259 files composing the system,
116  *	two compilers and a compiler generator: (all of which have
117  *	fairly large source files)
118  *
119  *	Number of files = 259
120  *		Number of non zero text reloc files: 233
121  *		Number of non zero data reloc files: 53
122  *	Average text relocation = 889
123  *	Average data relocation = 346
124  *	Number of files > BUFSIZ text relocation = 71
125  *	Number of files > BUFSIZ data relocation = 6
126  *
127  *	For compiled C code, there is usually one text segment and two
128  *	data segments; we see that allocating our own buffers and
129  *	doing our internal handling of relocation information will,
130  *	on the average, not use more memory than taken up by the buffers
131  *	allocated for doing file I/O in parallel to a number of file.
132  *
133  *	If we are assembling with the -V option, we
134  *	use the left over token buffers from the 2nd pass,
135  *	otherwise, we create our own.
136  *
137  *	When the 2nd pass is complete, closeoutrel flushes the token
138  *	buffers out to a BFILE.
139  *
140  *	The internals to relbufdesc are known only in assyms.c
141  *
142  *	outrel constructs the relocation information.
143  *	closeoutrel flushes the relocation information to relfil.
144  */
145 struct	relbufdesc	*rusefile[NLOC+NLOC];
146 struct	relbufdesc 	*relfil;	/* un concatnated relocation info */
147 BFILE	*relocfile;			/* concatnated relocation info */
148 /*
149  *	Once the relocation information has been written,
150  *	we can write out the symbol table using the Block I/O
151  *	mechanisms, as we once again know the offsets into
152  *	the a.out file.
153  *
154  *	We use relfil to output the symbol table information.
155  */
156 
157 char	*tmpdirprefix =
158 #ifdef UNIX
159 			"/tmp/";
160 #else VMS
161 			"/usr/tmp/";
162 #endif
163 
164 #define		TMP_SUFFIX	"asXXXXXX"
165 char		tmpn1[TNAMESIZE];
166 
167 int delexit();
168 
169 main(argc, argv)
170 	int	argc;
171 	char 	**argv;
172 {
173 
174 	tmpn1[0] = 0;
175 	endcore = (char *)sbrk(0);
176 
177 	argprocess(argc, argv);		/* process argument lists */
178 	if (anyerrs) exit(1);
179 
180 	initialize();
181 	zeroorigins();			/* set origins to zero */
182 	zerolocals();			/* fix local label counters */
183 
184 	i_pass1();			/* open temp files, etc */
185 	pass1();			/* first pass through .s files */
186 	testlocals();			/* check for undefined locals */
187 	if (anyerrs) delexit();
188 
189 	pass1_5();			/* resolve jxxx */
190 	if (anyerrs) delexit();
191 
192 	open_a_out();			/* open a.out */
193 	roundsegments();		/* round segments to FW */
194 	build_hdr();			/* build initial header, and output */
195 
196 	i_pass2();			/* reopen temporary file, etc */
197 	pass2();			/* second pass through the virtual .s */
198 	if (anyerrs) delexit();
199 
200 	fillsegments();			/* fill segments with 0 to FW */
201 	reloc_syms();			/* dump relocation and symbol table */
202 
203 	delete();			/* remove tmp file */
204 	bflush();			/* close off block I/O view of a.out */
205 	fix_a_out();			/* add in text and data reloc counts */
206 
207 	if (anyerrs == 0 && orgwarn)
208 		yyerror("Caution: absolute origins.\n");
209 	exit(anyerrs != 0);
210 }	/*end of UNIX main*/
211 
212 argprocess(argc, argv)
213 	int	argc;
214 	char	*argv[];
215 {
216 	register	char	*cp;
217 
218 	ninfiles = 0;
219 	silent = 0;
220 #ifdef DEBUG
221 	debug = 0;
222 #endif
223 	dotsname = "<argv error>";
224 	while (argc > 1) {
225 		if (argv[1][0] == '-'){
226 			cp = argv[1] + 1;
227 			/*
228 			 *	We can throw away single minus signs, so
229 			 *	that make scripts for the PDP 11 assembler work
230 			 *	on this assembler too
231 			 */
232 			while (*cp){
233 				switch(*cp++){
234 				 default:
235 					yyerror("Unknown flag: %c", *--cp);
236 					cp++;
237 					break;
238 				 case 'd':
239 					d124 = *cp++ - '0';
240 					if ( (d124 != 1) && (d124 != 2) &&
241 					     (d124 != 4)){
242 						yyerror("-d[124] only");
243 						exit(1);
244 					}
245 					break;
246 				 case 'o':
247 					if (argc < 3){
248 						yyerror("-o what???");
249 						exit(1);
250 					}
251 					outfile = argv[2];
252 				   bumpone:
253 					argc -= 2;
254 					argv += 2;
255 					goto nextarg;
256 
257 				 case 't':
258 					if (argc < 3){
259 						yyerror("-t what???");
260 						exit(1);
261 					}
262 					tmpdirprefix = argv[2];
263 					goto bumpone;
264 
265 				 case 'V':
266 					useVM = 1;
267 					break;
268 				 case 'W':
269 					silent = 1;
270 					break;
271 				 case 'L':
272 					savelabels = 1;
273 					break;
274 				 case 'J':
275 					jxxxJUMP = 1;
276 					break;
277 #ifdef DEBUG
278 				 case 'D':
279 					debug = 1;
280 					break;
281 				 case 'T':
282 					toktrace = 1;
283 					break;
284 #endif
285 				 case 'R':
286 					readonlydata = 1;
287 					break;
288 				}	/*end of the switch*/
289 			}	/*end of pulling out all arguments*/
290 		}	/*end of a flag argument*/
291 		else {	/*file name*/
292 			if (ninfiles > 32){
293 				yyerror("More than 32 file names");
294 				exit(3);
295 			}
296 			innames[ninfiles++] = argv[1];
297 		}
298 		--argc; ++argv;
299 	   nextarg:;
300 	}
301 }
302 
303 initialize()
304 {
305 	if (signal(SIGINT, SIG_IGN) != SIG_IGN)
306 		signal(SIGINT, delexit);
307 	/*
308 	 *	Install symbols in the table
309 	 */
310 	symtabinit();
311 	syminstall();
312 	/*
313 	 *	Build the expression parser accelerator token sets
314 	 */
315 	buildtokensets();
316 }
317 
318 zeroorigins()
319 {
320 	register	int	locindex;
321 	/*
322 	 *	Mark usedot: the first NLOC slots are for named text segments,
323 	 *	the next for named data segments.
324 	 */
325 	for (locindex = 0; locindex < NLOC; locindex++){
326 		usedot[locindex].e_xtype = XTEXT;
327 		usedot[NLOC + locindex].e_xtype = XDATA;
328 		usedot[locindex].e_xvalue = 0;
329 		usedot[NLOC + locindex].e_xvalue = 0;
330 		usedot[locindex].e_yvalue = 0;
331 		usedot[NLOC + locindex].e_yvalue = 0;
332 	}
333 }
334 
335 zerolocals()
336 {
337 	register	int	i;
338 
339 	for (i = 0; i <= 9; i++) {
340 		lgensym[i] = 1;
341 		genref[i] = 0;
342 	}
343 }
344 
345 i_pass1()
346 {
347 	if (useVM == 0){
348 		strcat(tmpn1, tmpdirprefix);
349 		strcat(tmpn1, TMP_SUFFIX);
350 		mktemp(tmpn1);
351 		tmpfil = fopen(tmpn1, "w");
352 		if (tmpfil==NULL) {
353 		  yyerror("Bad pass 1 temporary file for writing %s", tmpn1);
354 		  delexit();
355 		}
356 	}
357 
358 	inittmpfile();
359 	initijxxx();
360 }
361 
362 pass1()
363 {
364 	register	int	i;
365 
366 	passno = 1;
367 	dotp = &usedot[0];
368 	txtfil = (BFILE *)0;
369 	relfil = (struct relbufdesc *)0;
370 
371 	if (ninfiles == 0){		/*take the input from stdin directly*/
372 		lineno = 1;
373 		dotsname = "<stdin>";
374 
375 		yyparse();
376 	} else {		/*we have the names tanked*/
377 		for (i = 0; i < ninfiles; i++){
378 			new_dot_s(innames[i]);
379 			if (freopen(innames[i], "r", stdin) == NULL) {
380 				yyerror( "Can't open source file %s\n",
381 					innames[i]);
382 				exit(2);
383 			}
384 			/* stdio is NOT used to read the input characters */
385 			/* we use read directly, into our own buffers */
386 			yyparse();
387 		}
388 	}
389 
390 	closetmpfile();		/*kick out the last buffered intermediate text*/
391 }
392 
393 testlocals()
394 {
395 	register	int	i;
396 	for (i = 0; i <= 9; i++) {
397 		if (genref[i])
398 			yyerror("Reference to undefined local label %df", i);
399 		lgensym[i] = 1;
400 		genref[i] = 0;
401 	}
402 }
403 
404 pass1_5()
405 {
406 	sortsymtab();
407 #ifdef DEBUG
408 	if (debug) dumpsymtab();
409 #endif
410 	jxxxfix();
411 #ifdef DEBUG
412 	if (debug) dumpsymtab();
413 #endif
414 }
415 
416 open_a_out()
417 {
418 	/*
419 	 *	Open up the a.out file now, and get set to build
420 	 *	up offsets into it for all of the various text,data
421 	 *	text relocation and data relocation segments.
422 	 */
423 	a_out_file = fopen(outfile, "w");
424 	if (a_out_file == NULL) {
425 		yyerror("Cannot create %s", outfile);
426 		delexit();
427 	}
428 	biofd = a_out_file->_file;
429 	a_out_off = 0;
430 }
431 
432 roundsegments()
433 {
434 	register	int	locindex;
435 	register	long	v;
436 	/*
437 	 *	round and assign text segment origins
438 	 *	the exec header always goes in usefile[0]
439 	 */
440 	tsize = 0;
441 	for (locindex=0; locindex<NLOC; locindex++) {
442 		v = round(usedot[locindex].e_xvalue, FW);
443 		usedot[locindex].e_xvalue = tsize;
444 		if ((locindex == 0) || (v != 0) ){
445 			usefile[locindex] = (BFILE *)Calloc(1, sizeof(BFILE));
446 			bopen(usefile[locindex], a_out_off);
447 			if (locindex == 0)
448 				a_out_off = sizeof (struct exec);
449 		} else {
450 			usefile[locindex] = (BFILE *)-1;
451 		}
452 		tsize += v;
453 		a_out_off += v;
454 	}
455 	/*
456 	 *		Round and assign data segment origins.
457 	 */
458 	datbase = round(tsize, FW);
459 	for (locindex=0; locindex<NLOC; locindex++) {
460 		v = round(usedot[NLOC+locindex].e_xvalue, FW);
461 		usedot[NLOC+locindex].e_xvalue = datbase + dsize;
462 		if (v != 0){
463 			usefile[NLOC + locindex] = (BFILE *)Calloc(1,sizeof(BFILE));
464 			bopen(usefile[NLOC + locindex], a_out_off);
465 		} else {
466 			usefile[NLOC + locindex] = (BFILE *)-1;
467 		}
468 		dsize += v;
469 		a_out_off += v;
470 	}
471 	/*
472 	 *	Assign final values to symbols
473 	 */
474 	hdr.a_bss = dsize;
475 	freezesymtab();		/* this touches hdr.a_bss */
476 	stabfix();
477 	/*
478 	 *	Set up the relocation information "files" to
479 	 *	be zero; outrel takes care of the rest
480 	 */
481 	for (locindex = 0; locindex < NLOC + NLOC; locindex++){
482 		rusefile[locindex] = (struct relbufdesc *)0;
483 	}
484 }
485 
486 build_hdr()
487 {
488 	/*
489 	 *	Except for the text and data relocation sizes,
490 	 *	calculate the final values for the header
491 	 *
492 	 *	Write out the initial copy; we to come
493 	 *	back later and patch up a_trsize and a_drsize,
494 	 *	and overwrite this first version of the header.
495 	 */
496 	hdr.a_magic = MAGIC;
497 	hdr.a_text = tsize;
498 	hdr.a_data = dsize;
499 	hdr.a_bss -= dsize;
500 	hdr.a_syms = sizesymtab();	/* Does not include string pool length */
501 	hdr.a_entry = 0;
502 	hdr.a_trsize = 0;
503 	hdr.a_drsize = 0;
504 
505 	bwrite((char *)&hdr, sizeof(hdr), usefile[0]);
506 }
507 
508 i_pass2()
509 {
510 	if (useVM == 0) {
511 		fclose(tmpfil);
512 		tmpfil = fopen(tmpn1, "r");
513 		if (tmpfil==NULL) {
514 		   yyerror("Bad pass 2 temporary file for reading %s", tmpn1);
515 		   delexit();
516 		}
517 	}
518 }
519 
520 pass2()
521 {
522 #ifdef DEBUG
523 	if (debug)
524 		printf("\n\n\n\t\tPASS 2\n\n\n\n");
525 #endif DEBUG
526 	passno = 2;
527 	lineno = 1;
528 	dotp = &usedot[0];
529 	txtfil = usefile[0];	/* already opened (always!) */
530 	relfil = 0;		/* outrel takes care of the rest */
531 	initoutrel();
532 
533 	inittmpfile();
534 
535 	yyparse();
536 
537 	closetmpfile();
538 }
539 
540 fillsegments()
541 {
542 	int	locindex;
543 	/*
544 	 *	Round text and data segments to FW by appending zeros
545 	 */
546 	for (locindex = 0; locindex < NLOC + NLOC; locindex++) {
547 		if (usefile[locindex]) {
548 			txtfil = usefile[locindex];
549 			dotp = &usedot[locindex];
550 			while (usedot[locindex].e_xvalue & FW)
551 				outb(0);
552 		}
553 	}
554 }
555 
556 reloc_syms()
557 {
558 	u_long	closerelfil();
559 	/*
560 	 *	Move the relocation information to a.out
561 	 *	a_out_off is the offset so far:
562 	 *	exec + text segments + data segments
563 	 */
564 	relocfile = (BFILE *)Calloc(1,sizeof(BFILE));
565 	bopen(relocfile, a_out_off);
566 	a_out_off += closeoutrel(relocfile);
567 
568 	hdr.a_trsize = trsize;
569 	hdr.a_drsize = drsize;
570 	if (readonlydata) {
571 		hdr.a_text += hdr.a_data;
572 		hdr.a_data = 0;
573 		hdr.a_trsize += hdr.a_drsize;
574 		hdr.a_drsize = 0;
575 	}
576 	/*
577 	 *	Output the symbol table
578 	 *	and if FLEXNAMES is set, the string pool
579 	 */
580 	symwrite(relocfile);
581 }
582 
583 fix_a_out()
584 {
585 	if (lseek(a_out_file->_file, 0L, 0) < 0)
586 		yyerror("Reposition for header rewrite fails");
587 	if (write(a_out_file->_file, (char *)&hdr, sizeof (struct exec)) < 0)
588 		yyerror("Rewrite of header fails");
589 }
590 
591 delexit()
592 {
593 	delete();
594 	if (passno == 2){
595 		unlink(outfile);
596 	}
597 	exit(1);
598 }
599 
600 delete()
601 {
602 	if (useVM == 0 || tmpn1[0])
603 		unlink(tmpn1);
604 }
605 
606 sawabort()
607 {
608 	char	*fillinbuffer();
609 	while (fillinbuffer() != (char *)0)
610 		continue;
611 	delete();
612 	exit(1);	/*although the previous pass will also exit non zero*/
613 }
614 
615 panic(fmt, a1, a2, a3, a4)
616 	char	*fmt;
617 	/*VARARGS 1*/
618 {
619 	yyerror("Assembler panic: bad internal data structure.");
620 	yyerror(fmt, a1, a2, a3, a4);
621 	delete();
622 	abort();
623 }
624