xref: /original-bsd/usr.bin/pascal/src/fhdr.c (revision a1c2194a)
1 /*-
2  * Copyright (c) 1980 The Regents of the University of California.
3  * All rights reserved.
4  *
5  * %sccs.include.redist.c%
6  */
7 
8 #ifndef lint
9 static char sccsid[] = "@(#)fhdr.c	5.4 (Berkeley) 04/16/91";
10 #endif /* not lint */
11 
12 #include "whoami.h"
13 #include "0.h"
14 #include "tree.h"
15 #include "opcode.h"
16 #include "objfmt.h"
17 #include "align.h"
18 #include "tree_ty.h"
19 
20 /*
21  * this array keeps the pxp counters associated with
22  * functions and procedures, so that they can be output
23  * when their bodies are encountered
24  */
25 int	bodycnts[ DSPLYSZ ];
26 
27 #ifdef PC
28 #   include "pc.h"
29 #endif PC
30 
31 #ifdef OBJ
32 int	cntpatch;
33 int	nfppatch;
34 #endif OBJ
35 
36 /*
37  * Funchdr inserts
38  * declaration of a the
39  * prog/proc/func into the
40  * namelist. It also handles
41  * the arguments and puts out
42  * a transfer which defines
43  * the entry point of a procedure.
44  */
45 
46 struct nl *
47 funchdr(r)
48 	struct tnode *r;
49 {
50 	register struct nl *p;
51 	register struct tnode *rl;
52 	struct nl *cp, *dp, *temp;
53 	int o;
54 
55 	if (inpflist(r->p_dec.id_ptr)) {
56 		opush('l');
57 		yyretrieve();	/* kludge */
58 	}
59 	pfcnt++;
60 	parts[ cbn ] |= RPRT;
61 	line = r->p_dec.line_no;
62 	if (r->p_dec.param_list == TR_NIL &&
63 		(p=lookup1(r->p_dec.id_ptr)) != NIL && bn == cbn) {
64 		/*
65 		 * Symbol already defined
66 		 * in this block. it is either
67 		 * a redeclared symbol (error)
68 		 * a forward declaration,
69 		 * or an external declaration.
70 		 * check that forwards are of the right kind:
71 		 *     if this fails, we are trying to redefine it
72 		 *     and enter() will complain.
73 		 */
74 		if (  ( ( p->nl_flags & NFORWD ) != 0 )
75 		   && (  ( p->class == FUNC && r->tag == T_FDEC )
76 		      || ( p->class == PROC && r->tag == T_PDEC ) ) ) {
77 			/*
78 			 * Grammar doesnt forbid
79 			 * types on a resolution
80 			 * of a forward function
81 			 * declaration.
82 			 */
83 			if (p->class == FUNC && r->p_dec.type)
84 				error("Function type should be given only in forward declaration");
85 			/*
86 			 * get another counter for the actual
87 			 */
88 			if ( monflg ) {
89 			    bodycnts[ cbn ] = getcnt();
90 			}
91 #			ifdef PC
92 			    enclosing[ cbn ] = p -> symbol;
93 #			endif PC
94 #			ifdef PTREE
95 				/*
96 				 *	mark this proc/func as forward
97 				 *	in the pTree.
98 				 */
99 			    pDEF( p -> inTree ).PorFForward = TRUE;
100 #			endif PTREE
101 			return (p);
102 		}
103 	}
104 
105 	/* if a routine segment is being compiled,
106 	 * do level one processing.
107 	 */
108 
109 	 if ((r->tag != T_PROG) && (!progseen))
110 		level1();
111 
112 
113 	/*
114 	 * Declare the prog/proc/func
115 	 */
116 	switch (r->tag) {
117 	    case T_PROG:
118 		    progseen = TRUE;
119 		    if (opt('z'))
120 			    monflg = TRUE;
121 		    program = p = defnl(r->p_dec.id_ptr, PROG, NLNIL, 0);
122 		    p->value[3] = r->p_dec.line_no;
123 		    break;
124 	    case T_PDEC:
125 		    if (r->p_dec.type != TR_NIL)
126 			    error("Procedures do not have types, only functions do");
127 		    p = enter(defnl(r->p_dec.id_ptr, PROC, NLNIL, 0));
128 		    p->nl_flags |= NMOD;
129 #		    ifdef PC
130 			enclosing[ cbn ] = r->p_dec.id_ptr;
131 			p -> extra_flags |= NGLOBAL;
132 #		    endif PC
133 		    break;
134 	    case T_FDEC:
135 		    {
136 			register struct tnode *il;
137 		    il = r->p_dec.type;
138 		    if (il == TR_NIL) {
139 			    temp = NLNIL;
140 			    error("Function type must be specified");
141 		    } else if (il->tag != T_TYID) {
142 			    temp = NLNIL;
143 			    error("Function type can be specified only by using a type identifier");
144 		    } else
145 			    temp = gtype(il);
146 		    }
147 		    p = enter(defnl(r->p_dec.id_ptr, FUNC, temp, NIL));
148 		    p->nl_flags |= NMOD;
149 		    /*
150 		     * An arbitrary restriction
151 		     */
152 		    switch (o = classify(p->type)) {
153 			    case TFILE:
154 			    case TARY:
155 			    case TREC:
156 			    case TSET:
157 			    case TSTR:
158 				    warning();
159 				    if (opt('s')) {
160 					    standard();
161 				    }
162 				    error("Functions should not return %ss", clnames[o]);
163 		    }
164 #		    ifdef PC
165 			enclosing[ cbn ] = r->p_dec.id_ptr;
166 			p -> extra_flags |= NGLOBAL;
167 #		    endif PC
168 		    break;
169 	    default:
170 		    panic("funchdr");
171 	}
172 	if (r->tag != T_PROG) {
173 		/*
174 		 * Mark this proc/func as
175 		 * being forward declared
176 		 */
177 		p->nl_flags |= NFORWD;
178 		/*
179 		 * Enter the parameters
180 		 * in the next block for
181 		 * the time being
182 		 */
183 		if (++cbn >= DSPLYSZ) {
184 			error("Procedure/function nesting too deep");
185 			pexit(ERRS);
186 		}
187 		/*
188 		 * For functions, the function variable
189 		 */
190 		if (p->class == FUNC) {
191 #			ifdef OBJ
192 			    cp = defnl(r->p_dec.id_ptr, FVAR, p->type, 0);
193 #			endif OBJ
194 #			ifdef PC
195 				/*
196 				 * fvars used to be allocated and deallocated
197 				 * by the caller right before the arguments.
198 				 * the offset of the fvar was kept in
199 				 * value[NL_OFFS] of function (very wierd,
200 				 * but see asgnop).
201 				 * now, they are locals to the function
202 				 * with the offset kept in the fvar.
203 				 */
204 
205 			    cp = defnl(r->p_dec.id_ptr, FVAR, p->type,
206 				(int)-roundup(roundup(
207 			            (int)(DPOFF1+lwidth(p->type)),
208 				    (long)align(p->type))), (long) A_STACK);
209 			    cp -> extra_flags |= NLOCAL;
210 #			endif PC
211 			cp->chain = p;
212 			p->ptr[NL_FVAR] = cp;
213 		}
214 		/*
215 		 * Enter the parameters
216 		 * and compute total size
217 		 */
218 	        p->value[NL_OFFS] = params(p, r->p_dec.param_list);
219 		/*
220 		 * because NL_LINENO field in the function
221 		 * namelist entry has been used (as have all
222 		 * the other fields), the line number is
223 		 * stored in the NL_LINENO field of its fvar.
224 		 */
225 		if (p->class == FUNC)
226 		    p->ptr[NL_FVAR]->value[NL_LINENO] = r->p_dec.line_no;
227 		else
228 		    p->value[NL_LINENO] = r->p_dec.line_no;
229 		cbn--;
230 	} else {
231 		/*
232 		 * The wonderful
233 		 * program statement!
234 		 */
235 #		ifdef OBJ
236 		    if (monflg) {
237 			    (void) put(1, O_PXPBUF);
238 			    cntpatch = put(2, O_CASE4, (long)0);
239 			    nfppatch = put(2, O_CASE4, (long)0);
240 		    }
241 #		endif OBJ
242 		cp = p;
243 		for (rl = r->p_dec.param_list; rl; rl = rl->list_node.next) {
244 			if (rl->list_node.list == TR_NIL)
245 				continue;
246 			dp = defnl((char *) rl->list_node.list, VAR, NLNIL, 0);
247 			cp->chain = dp;
248 			cp = dp;
249 		}
250 	}
251 	/*
252 	 * Define a branch at
253 	 * the "entry point" of
254 	 * the prog/proc/func.
255 	 */
256 	p->value[NL_ENTLOC] = (int) getlab();
257 	if (monflg) {
258 		bodycnts[ cbn ] = getcnt();
259 		p->value[ NL_CNTR ] = 0;
260 	}
261 #	ifdef OBJ
262 	    (void) put(2, O_TRA4, (long)p->value[NL_ENTLOC]);
263 #	endif OBJ
264 #	ifdef PTREE
265 	    {
266 		pPointer	PF = tCopy( r );
267 
268 		pSeize( PorFHeader[ nesting ] );
269 		if ( r->tag != T_PROG ) {
270 			pPointer	*PFs;
271 
272 			PFs = &( pDEF( PorFHeader[ nesting ] ).PorFPFs );
273 			*PFs = ListAppend( *PFs , PF );
274 		} else {
275 			pDEF( PorFHeader[ nesting ] ).GlobProg = PF;
276 		}
277 		pRelease( PorFHeader[ nesting ] );
278 	    }
279 #	endif PTREE
280 	return (p);
281 }
282 
283 	/*
284 	 * deal with the parameter declaration for a routine.
285 	 * p is the namelist entry of the routine.
286 	 * formalist is the parse tree for the parameter declaration.
287 	 * formalist	[0]	T_LISTPP
288 	 *		[1]	pointer to a formal
289 	 *		[2]	pointer to next formal
290 	 * for by-value or by-reference formals, the formal is
291 	 * formal	[0]	T_PVAL or T_PVAR
292 	 *		[1]	pointer to id_list
293 	 *		[2]	pointer to type (error if not typeid)
294 	 * for function and procedure formals, the formal is
295 	 * formal	[0]	T_PFUNC or T_PPROC
296 	 *		[1]	pointer to id_list (error if more than one)
297 	 *		[2]	pointer to type (error if not typeid, or proc)
298 	 *		[3]	pointer to formalist for this routine.
299 	 */
300 fparams(p, formal)
301 	register struct nl *p;
302 	struct tnode *formal;		/* T_PFUNC or T_PPROC */
303 {
304 	(void) params(p, formal->pfunc_node.param_list);
305 	p -> value[ NL_LINENO ] = formal->pfunc_node.line_no;
306 	p -> ptr[ NL_FCHAIN ] = p -> chain;
307 	p -> chain = NIL;
308 }
309 
310 params(p, formalist)
311 	register struct nl *p;
312 	struct tnode *formalist;	/* T_LISTPP */
313 {
314 	struct nl *chainp, *savedp;
315 	struct nl *dp;
316 	register struct tnode *formalp;	/* an element of the formal list */
317 	register struct tnode *formal;	/* a formal */
318 	struct tnode *r, *s, *t, *typ, *idlist;
319 	int w, o;
320 
321 	/*
322 	 * Enter the parameters
323 	 * and compute total size
324 	 */
325 	chainp = savedp = p;
326 
327 #	ifdef OBJ
328 	    o = 0;
329 #	endif OBJ
330 #	ifdef PC
331 		/*
332 		 * parameters used to be allocated backwards,
333 		 * then fixed.  for pc, they are allocated correctly.
334 		 * also, they are aligned.
335 		 */
336 	    o = DPOFF2;
337 #	endif PC
338 	for (formalp = formalist; formalp != TR_NIL;
339 			formalp = formalp->list_node.next) {
340 		formal = formalp->list_node.list;
341 		if (formal == TR_NIL)
342 			continue;
343 		/*
344 		 * Parametric procedures
345 		 * don't have types !?!
346 		 */
347 		typ = formal->pfunc_node.type;
348 		p = NLNIL;
349 		if ( typ == TR_NIL ) {
350 		    if ( formal->tag != T_PPROC ) {
351 			error("Types must be specified for arguments");
352 		    }
353 		} else {
354 		    if ( formal->tag == T_PPROC ) {
355 			error("Procedures cannot have types");
356 		    } else {
357 			p = gtype(typ);
358 		    }
359 		}
360 		for (idlist = formal->param.id_list; idlist != TR_NIL;
361 				idlist = idlist->list_node.next) {
362 			switch (formal->tag) {
363 			    default:
364 				    panic("funchdr2");
365 			    case T_PVAL:
366 				    if (p != NLNIL) {
367 					    if (p->class == FILET)
368 						    error("Files cannot be passed by value");
369 					    else if (p->nl_flags & NFILES)
370 						    error("Files cannot be a component of %ss passed by value",
371 							    nameof(p));
372 				    }
373 #				    ifdef OBJ
374 					w = lwidth(p);
375 					o -= roundup(w, (long) A_STACK);
376 #					ifdef DEC11
377 					    dp = defnl((char *) idlist->list_node.list,
378 								VAR, p, o);
379 #					else
380 					    dp = defnl((char *) idlist->list_node.list,
381 						    VAR,p, (w < 2) ? o + 1 : o);
382 #					endif DEC11
383 #				    endif OBJ
384 #				    ifdef PC
385 					o = roundup(o, (long) A_STACK);
386 					w = lwidth(p);
387 #					ifndef DEC11
388 					    if (w <= sizeof(int)) {
389 						o += sizeof(int) - w;
390 					    }
391 #					endif not DEC11
392 					dp = defnl((char *) idlist->list_node.list,VAR,
393 							p, o);
394 					o += w;
395 #				    endif PC
396 				    dp->nl_flags |= NMOD;
397 				    break;
398 			    case T_PVAR:
399 #				    ifdef OBJ
400 					dp = defnl((char *) idlist->list_node.list, REF,
401 						    p, o -= sizeof ( int * ) );
402 #				    endif OBJ
403 #				    ifdef PC
404 					dp = defnl( (char *) idlist->list_node.list, REF,
405 						    p ,
406 					    o = roundup( o , (long)A_STACK ) );
407 					o += sizeof(char *);
408 #				    endif PC
409 				    break;
410 			    case T_PFUNC:
411 				    if (idlist->list_node.next != TR_NIL) {
412 					error("Each function argument must be declared separately");
413 					idlist->list_node.next = TR_NIL;
414 				    }
415 #				    ifdef OBJ
416 					dp = defnl((char *) idlist->list_node.list,FFUNC,
417 						p, o -= sizeof ( int * ) );
418 #				    endif OBJ
419 #				    ifdef PC
420 					dp = defnl( (char *) idlist->list_node.list ,
421 						FFUNC , p ,
422 						o = roundup( o , (long)A_STACK ) );
423 					o += sizeof(char *);
424 #				    endif PC
425 				    dp -> nl_flags |= NMOD;
426 				    fparams(dp, formal);
427 				    break;
428 			    case T_PPROC:
429 				    if (idlist->list_node.next != TR_NIL) {
430 					error("Each procedure argument must be declared separately");
431 					idlist->list_node.next = TR_NIL;
432 				    }
433 #				    ifdef OBJ
434 					dp = defnl((char *) idlist->list_node.list,
435 					    FPROC, p, o -= sizeof ( int * ) );
436 #				    endif OBJ
437 #				    ifdef PC
438 					dp = defnl( (char *) idlist->list_node.list ,
439 						FPROC , p,
440 						o = roundup( o , (long)A_STACK ) );
441 					o += sizeof(char *);
442 #				    endif PC
443 				    dp -> nl_flags |= NMOD;
444 				    fparams(dp, formal);
445 				    break;
446 			    }
447 			if (dp != NLNIL) {
448 #				ifdef PC
449 				    dp -> extra_flags |= NPARAM;
450 #				endif PC
451 				chainp->chain = dp;
452 				chainp = dp;
453 			}
454 		}
455 		if (typ != TR_NIL && typ->tag == T_TYCARY) {
456 #		    ifdef OBJ
457 			w = -roundup(lwidth(p->chain), (long) A_STACK);
458 #			ifndef DEC11
459 			    w = (w > -2)? w + 1 : w;
460 #			endif
461 #		    endif OBJ
462 #		    ifdef PC
463 			w = lwidth(p->chain);
464 			o = roundup(o, (long)A_STACK);
465 #		    endif PC
466 		    /*
467 		     * Allocate space for upper and
468 		     * lower bounds and width.
469 		     */
470 		    for (s=typ; s->tag == T_TYCARY; s = s->ary_ty.type) {
471 			for (r=s->ary_ty.type_list; r != TR_NIL;
472 						r = r->list_node.next) {
473 			    t = r->list_node.list;
474 			    p = p->chain;
475 #			    ifdef OBJ
476 				o += w;
477 #			    endif OBJ
478 			    chainp->chain = defnl(t->crang_ty.lwb_var,
479 								VAR, p, o);
480 			    chainp = chainp->chain;
481 			    chainp->nl_flags |= (NMOD | NUSED);
482 			    p->nptr[0] = chainp;
483 			    o += w;
484 			    chainp->chain = defnl(t->crang_ty.upb_var,
485 								VAR, p, o);
486 			    chainp = chainp->chain;
487 			    chainp->nl_flags |= (NMOD | NUSED);
488 			    p->nptr[1] = chainp;
489 			    o += w;
490 			    chainp->chain  = defnl(0, VAR, p, o);
491 			    chainp = chainp->chain;
492 			    chainp->nl_flags |= (NMOD | NUSED);
493 			    p->nptr[2] = chainp;
494 #			    ifdef PC
495 				o += w;
496 #			    endif PC
497 			}
498 		    }
499 		}
500 	}
501 	p = savedp;
502 #	ifdef OBJ
503 		/*
504 		 * Correct the naivete (naivety)
505 		 * of our above code to
506 		 * calculate offsets
507 		 */
508 	    for (dp = p->chain; dp != NLNIL; dp = dp->chain)
509 		    dp->value[NL_OFFS] += -o + DPOFF2;
510 	    return (-o + DPOFF2);
511 #	endif OBJ
512 #	ifdef PC
513 	    return roundup( o , (long)A_STACK );
514 #	endif PC
515 }
516