xref: /original-bsd/usr.bin/pascal/src/stkrval.c (revision fb9118b1)
1 /*
2  * Copyright (c) 1980 Regents of the University of California.
3  * All rights reserved.  The Berkeley software License Agreement
4  * specifies the terms and conditions for redistribution.
5  */
6 
7 #ifndef lint
8 static char sccsid[] = "@(#)stkrval.c	5.2 (Berkeley) 11/12/86";
9 #endif not lint
10 
11 #include "whoami.h"
12 #include "0.h"
13 #include "tree.h"
14 #include "opcode.h"
15 #include "objfmt.h"
16 #include "align.h"
17 #ifdef PC
18 #   include <pcc.h>
19 #endif PC
20 #include "tree_ty.h"
21 
22 /*
23  * stkrval Rvalue - an expression, and coerce it to be a stack quantity.
24  *
25  * Contype is the type that the caller would prefer, nand is important
26  * if constant sets or constant strings are involved, the latter
27  * because of string padding.
28  */
29 /*
30  * for the obj version, this is a copy of rvalue hacked to use fancy new
31  * push-onto-stack-and-convert opcodes.
32  * for the pc version, i just call rvalue and convert if i have to,
33  * based on the return type of rvalue.
34  */
35 struct nl *
36 stkrval(r, contype , required )
37 	register struct tnode *r;
38 	struct nl *contype;
39 	long	required;
40 {
41 	register struct nl *p;
42 	register struct nl *q;
43 	register char *cp, *cp1;
44 	register int c, w;
45 	struct tnode *pt;
46 	long l;
47 	union
48 	{
49 		double pdouble;
50 		long   plong[2];
51 	}f;
52 
53 	if (r == TR_NIL)
54 		return (NLNIL);
55 	if (nowexp(r))
56 		return (NLNIL);
57 	/*
58 	 * The root of the tree tells us what sort of expression we have.
59 	 */
60 	switch (r->tag) {
61 
62 	/*
63 	 * The constant nil
64 	 */
65 	case T_NIL:
66 #		ifdef OBJ
67 		    (void) put(2, O_CON14, 0);
68 #		endif OBJ
69 #		ifdef PC
70 		    putleaf( PCC_ICON , 0 , 0 , PCCT_INT , (char *) 0 );
71 #		endif PC
72 		return (nl+TNIL);
73 
74 	case T_FCALL:
75 	case T_VAR:
76 		p = lookup(r->var_node.cptr);
77 		if (p == NLNIL || p->class == BADUSE)
78 			return (NLNIL);
79 		switch (p->class) {
80 		case VAR:
81 			/*
82 			 * if a variable is
83 			 * qualified then get
84 			 * the rvalue by a
85 			 * stklval and an ind.
86 			 */
87 			if (r->var_node.qual != TR_NIL)
88 				goto ind;
89 			q = p->type;
90 			if (q == NLNIL)
91 				return (NLNIL);
92 			if (classify(q) == TSTR)
93 				return(stklval(r, NOFLAGS));
94 #			ifdef OBJ
95 				return (stackRV(p));
96 #			endif OBJ
97 #			ifdef PC
98 			    q = rvalue( r , contype , (int) required );
99 			    if (isa(q, "sbci")) {
100 				sconv(p2type(q),PCCT_INT);
101 			    }
102 			    return q;
103 #			endif PC
104 
105 		case WITHPTR:
106 		case REF:
107 			/*
108 			 * A stklval for these
109 			 * is actually what one
110 			 * might consider a rvalue.
111 			 */
112 ind:
113 			q = stklval(r, NOFLAGS);
114 			if (q == NLNIL)
115 				return (NLNIL);
116 			if (classify(q) == TSTR)
117 				return(q);
118 #			ifdef OBJ
119 			    w = width(q);
120 			    switch (w) {
121 				    case 8:
122 					    (void) put(1, O_IND8);
123 					    return(q);
124 				    case 4:
125 					    (void) put(1, O_IND4);
126 					    return(q);
127 				    case 2:
128 					    (void) put(1, O_IND24);
129 					    return(q);
130 				    case 1:
131 					    (void) put(1, O_IND14);
132 					    return(q);
133 				    default:
134 					    (void) put(2, O_IND, w);
135 					    return(q);
136 			    }
137 #			endif OBJ
138 #			ifdef PC
139 			    if ( required == RREQ ) {
140 				putop( PCCOM_UNARY PCC_MUL , p2type( q ) );
141 				if (isa(q,"sbci")) {
142 				    sconv(p2type(q),PCCT_INT);
143 				}
144 			    }
145 			    return q;
146 #			endif PC
147 
148 		case CONST:
149 			if (r->var_node.qual != TR_NIL) {
150 				error("%s is a constant and cannot be qualified", r->var_node.cptr);
151 				return (NLNIL);
152 			}
153 			q = p->type;
154 			if (q == NLNIL)
155 				return (NLNIL);
156 			if (q == nl+TSTR) {
157 				/*
158 				 * Find the size of the string
159 				 * constant if needed.
160 				 */
161 				cp = (char *) p->ptr[0];
162 cstrng:
163 				cp1 = cp;
164 				for (c = 0; *cp++; c++)
165 					continue;
166 				w = c;
167 				if (contype != NIL && !opt('s')) {
168 					if (width(contype) < c && classify(contype) == TSTR) {
169 						error("Constant string too long");
170 						return (NLNIL);
171 					}
172 					w = width(contype);
173 				}
174 #				ifdef OBJ
175 				    (void) put(2, O_LVCON, lenstr(cp1, w - c));
176 				    putstr(cp1, w - c);
177 #				endif OBJ
178 #				ifdef PC
179 				    putCONG( cp1 , w , LREQ );
180 #				endif PC
181 				/*
182 				 * Define the string temporarily
183 				 * so later people can know its
184 				 * width.
185 				 * cleaned out by stat.
186 				 */
187 				q = defnl((char *) 0, STR, NLNIL, w);
188 				q->type = q;
189 				return (q);
190 			}
191 			if (q == nl+T1CHAR) {
192 #			    ifdef OBJ
193 				(void) put(2, O_CONC4, (int)p->value[0]);
194 #			    endif OBJ
195 #			    ifdef PC
196 				putleaf(PCC_ICON, p -> value[0], 0, PCCT_INT,
197 						(char *) 0);
198 #			    endif PC
199 			    return(q);
200 			}
201 			/*
202 			 * Every other kind of constant here
203 			 */
204 #			ifdef OBJ
205 			    switch (width(q)) {
206 			    case 8:
207 #ifndef DEBUG
208 				    (void) put(2, O_CON8, p->real);
209 				    return(q);
210 #else
211 				    if (hp21mx) {
212 					    f.pdouble = p->real;
213 					    conv((int *) (&f.pdouble));
214 					    l = f.plong[1];
215 					    (void) put(2, O_CON4, l);
216 				    } else
217 					    (void) put(2, O_CON8, p->real);
218 				    return(q);
219 #endif
220 			    case 4:
221 				    (void) put(2, O_CON4, p->range[0]);
222 				    return(q);
223 			    case 2:
224 				    (void) put(2, O_CON24, (short)p->range[0]);
225 				    return(q);
226 			    case 1:
227 				    (void) put(2, O_CON14, p->value[0]);
228 				    return(q);
229 			    default:
230 				    panic("stkrval");
231 			    }
232 #			endif OBJ
233 #			ifdef PC
234 			    q = rvalue( r , contype , (int) required );
235 			    if (isa(q,"sbci")) {
236 				sconv(p2type(q),PCCT_INT);
237 			    }
238 			    return q;
239 #			endif PC
240 
241 		case FUNC:
242 		case FFUNC:
243 			/*
244 			 * Function call
245 			 */
246 			pt = r->var_node.qual;
247 			if (pt != TR_NIL) {
248 				switch (pt->list_node.list->tag) {
249 				case T_PTR:
250 				case T_ARGL:
251 				case T_ARY:
252 				case T_FIELD:
253 					error("Can't qualify a function result value");
254 					return (NLNIL);
255 				}
256 			}
257 #			ifdef OBJ
258 			    q = p->type;
259 			    if (classify(q) == TSTR) {
260 				    c = width(q);
261 				    (void) put(2, O_LVCON,
262 					roundup(c+1, (long) A_SHORT));
263 				    putstr("", c);
264 				    (void) put(1, PTR_DUP);
265 				    p = funccod(r);
266 				    (void) put(2, O_AS, c);
267 				    return(p);
268 			    }
269 			    p = funccod(r);
270 			    if (width(p) <= 2)
271 				    (void) put(1, O_STOI);
272 #			endif OBJ
273 #			ifdef PC
274 			    p = pcfunccod( r );
275 			    if (isa(p,"sbci")) {
276 				sconv(p2type(p),PCCT_INT);
277 			    }
278 #			endif PC
279 			return (p);
280 
281 		case TYPE:
282 			error("Type names (e.g. %s) allowed only in declarations", p->symbol);
283 			return (NLNIL);
284 
285 		case PROC:
286 		case FPROC:
287 			error("Procedure %s found where expression required", p->symbol);
288 			return (NLNIL);
289 		default:
290 			panic("stkrvid");
291 		}
292 	case T_PLUS:
293 	case T_MINUS:
294 	case T_NOT:
295 	case T_AND:
296 	case T_OR:
297 	case T_DIVD:
298 	case T_MULT:
299 	case T_SUB:
300 	case T_ADD:
301 	case T_MOD:
302 	case T_DIV:
303 	case T_EQ:
304 	case T_NE:
305 	case T_GE:
306 	case T_LE:
307 	case T_GT:
308 	case T_LT:
309 	case T_IN:
310 		p = rvalue(r, contype , (int) required );
311 #		ifdef OBJ
312 		    if (width(p) <= 2)
313 			    (void) put(1, O_STOI);
314 #		endif OBJ
315 #		ifdef PC
316 		    if (isa(p,"sbci")) {
317 			sconv(p2type(p),PCCT_INT);
318 		    }
319 #		endif PC
320 		return (p);
321 	case T_CSET:
322 		p = rvalue(r, contype , (int) required );
323 		return (p);
324 	default:
325 		if (r->const_node.cptr == (char *) NIL)
326 			return (NLNIL);
327 		switch (r->tag) {
328 		default:
329 			panic("stkrval3");
330 
331 		/*
332 		 * An octal number
333 		 */
334 		case T_BINT:
335 			f.pdouble = a8tol(r->const_node.cptr);
336 			goto conint;
337 
338 		/*
339 		 * A decimal number
340 		 */
341 		case T_INT:
342 			f.pdouble = atof(r->const_node.cptr);
343 conint:
344 			if (f.pdouble > MAXINT || f.pdouble < MININT) {
345 				error("Constant too large for this implementation");
346 				return (NLNIL);
347 			}
348 			l = f.pdouble;
349 			if (bytes(l, l) <= 2) {
350 #			    ifdef OBJ
351 				(void) put(2, O_CON24, (short)l);
352 #			    endif OBJ
353 #			    ifdef PC
354 				putleaf( PCC_ICON , (short) l , 0 , PCCT_INT ,
355 						(char *) 0 );
356 #			    endif PC
357 				return(nl+T4INT);
358 			}
359 #			ifdef OBJ
360 			    (void) put(2, O_CON4, l);
361 #			endif OBJ
362 #			ifdef PC
363 			    putleaf( PCC_ICON , (int) l , 0 , PCCT_INT , (char *) 0 );
364 #			endif PC
365 			return (nl+T4INT);
366 
367 		/*
368 		 * A floating point number
369 		 */
370 		case T_FINT:
371 #		   	ifdef OBJ
372 			    (void) put(2, O_CON8, atof(r->const_node.cptr));
373 #			endif OBJ
374 #			ifdef PC
375 			    putCON8( atof( r->const_node.cptr ) );
376 #			endif PC
377 			return (nl+TDOUBLE);
378 
379 		/*
380 		 * Constant strings.  Note that constant characters
381 		 * are constant strings of length one; there is
382 		 * no constant string of length one.
383 		 */
384 		case T_STRNG:
385 			cp = r->const_node.cptr;
386 			if (cp[1] == 0) {
387 #				ifdef OBJ
388 				    (void) put(2, O_CONC4, cp[0]);
389 #				endif OBJ
390 #				ifdef PC
391 				    putleaf( PCC_ICON , cp[0] , 0 , PCCT_INT ,
392 						(char *) 0 );
393 #				endif PC
394 				return(nl+T1CHAR);
395 			}
396 			goto cstrng;
397 		}
398 
399 	}
400 }
401 
402 #ifdef OBJ
403 /*
404  * push a value onto the interpreter stack, longword aligned.
405  */
406 struct nl
407 *stackRV(p)
408 	struct nl *p;
409 {
410 	struct nl *q;
411 	int w, bn;
412 
413 	q = p->type;
414 	if (q == NLNIL)
415 		return (NLNIL);
416 	bn = BLOCKNO(p->nl_block);
417 	w = width(q);
418 	switch (w) {
419 	case 8:
420 		(void) put(2, O_RV8 | bn << 8+INDX, (int)p->value[0]);
421 		break;
422 	case 4:
423 		(void) put(2, O_RV4 | bn << 8+INDX, (int)p->value[0]);
424 		break;
425 	case 2:
426 		(void) put(2, O_RV24 | bn << 8+INDX, (int)p->value[0]);
427 		break;
428 	case 1:
429 		(void) put(2, O_RV14 | bn << 8+INDX, (int)p->value[0]);
430 		break;
431 	default:
432 		(void) put(3, O_RV | bn << 8+INDX, (int)p->value[0], w);
433 		break;
434 	}
435 	return (q);
436 }
437 #endif OBJ
438