4.4BSD/usr/src/usr.bin/pascal/src/case.c
/*-
* Copyright (c) 1980, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifndef lint
static char sccsid[] = "@(#)case.c 8.1 (Berkeley) 6/6/93";
#endif /* not lint */
#include "whoami.h"
#include "0.h"
#include "tree.h"
#include "opcode.h"
#include "tree_ty.h"
/*
* The structure used to
* hold information about
* each case label.
*/
struct ct {
long clong;
int cline;
};
#ifdef OBJ
/*
* Caseop generates the
* pascal case statement code
*/
caseop(rnode)
WHI_CAS *rnode;
{
register struct nl *p;
register struct ct *ctab;
register struct tnode *cs;
extern char *lc;
double low, high;
short *brtab;
char *brtab0;
char *csend;
int w, j, m, n;
int goc;
bool nr;
goc = gocnt;
/*
* Obtain selector attributes:
* p type
* w width
* low lwb(p)
* high upb(p)
*/
p = rvalue(rnode->expr, NLNIL , RREQ );
{
register struct nl *cl;
if (p != NLNIL) {
if (isnta(p, "bcsi")) {
error("Case selectors cannot be %ss", nameof(p));
p = NLNIL;
} else {
cl = p;
if (p->class != (char) RANGE)
cl = p->type;
if (cl == NLNIL)
p = NLNIL;
else {
w = width(p);
#ifdef DEBUG
if (hp21mx)
w = 2;
#endif
low = cl->range[0];
high = cl->range[1];
}
}
}
} /* local declaration */
{
struct tnode *cl; /* list node */
/*
* Count # of cases
*/
n = 0;
for (cl = rnode->stmnt_list; cl != TR_NIL;
cl = cl->list_node.next) {
cs = cl->list_node.list;;
if (cs == TR_NIL)
continue;
for (cs = cs->c_stmnt.const_list; cs != TR_NIL;
cs = cs->list_node.next)
n++;
}
} /* local declaration */
/*
* Allocate case table space
*/
{
char *i;
i = malloc((unsigned) n * sizeof *ctab);
if (i == 0) {
error("Ran out of memory (case)");
pexit(DIED);
}
ctab = (struct ct *) i;
}
/*
* Check the legality of the
* labels and count the number
* of good labels
*/
{
register struct tnode *cl;
m = 0;
for (cl = rnode->stmnt_list; cl != TR_NIL;
cl = cl->list_node.next) {
cs = cl->list_node.list;
if (cs == TR_NIL)
continue;
line = cs->c_stmnt.line_no;
for (cs = cs->c_stmnt.const_list; cs != TR_NIL;
cs = cs->list_node.next) {
gconst(cs->list_node.list);
if (p == NLNIL || con.ctype == NIL)
continue;
if (incompat(con.ctype, p, TR_NIL )) {
cerror("Case label type clashed with case selector expression type");
continue;
}
if (con.crval < low || con.crval > high) {
error("Case label out of range");
continue;
}
ctab[m].clong = con.crval;
ctab[m].cline = line;
m++;
}
}
} /* decl of cl */
{
register int i;
/*
* Check for duplicate labels
*/
for (i = 0; i < m; i++)
for (j = 0; j < m; j++)
if (ctab[i].clong == ctab[j].clong) {
if (i == j)
continue;
if (j < i)
break;
error("Multiply defined label in case, lines %d and %d", (char *) ctab[i].cline, (char *) ctab[j].cline);
}
}
/*
* Put out case operator and
* leave space for the
* branch table
*/
if (p != NLNIL) {
(void) put(2, O_CASE1OP + (w >> 1), n);
brtab0 = lc;
brtab = ((short *) brtab0);
putspace(n * 2);
(void) put(1, O_CASEBEG);
{
int i;
for (i=0; i<m; i++)
if (w <= 2)
(void) put(2 ,O_CASE1 + (w >> 1), (int)ctab[i].clong);
else
(void) put(2 ,O_CASE4, ctab[i].clong);
}
(void) put(1, O_CASEEND);
}
csend = getlab();
(void) put(2, O_TRA, csend);
/*
* Free the case
* table space.
*/
free((char *) ctab);
/*
* Generate code for each
* statement. Patch branch
* table to beginning of each
* statement and follow each
* statement with a branch back
* to the TRA above.
*/
{
register struct tnode *cl;
nr = TRUE;
for (cl = rnode->stmnt_list; cl != TR_NIL;
cl = cl->list_node.next) {
cs = cl->list_node.list;
if (cs == TR_NIL)
continue;
if (p != NLNIL)
for (cs = cs->c_stmnt.const_list; cs != TR_NIL;
cs = cs->list_node.next) {
#ifdef ADDR16
patchfil(((char *) (brtab - 1)),
(long)(lc - brtab0), 1);
#endif ADDR16
#ifdef ADDR32
patchfil( ((unsigned long) (brtab - 1)),
(long)(lc - brtab0), 1);
#endif ADDR32
brtab++;
}
cs = cl->list_node.list;
putcnt();
level++;
statement(cs->c_stmnt.stmnt);
nr = (bool)(noreach && nr);
noreach = FALSE;
(void) put(2, O_TRA, csend);
level--;
if (gotos[cbn])
ungoto();
}
} /* decl of cl */
/*
* Patch the termination branch
*/
#ifdef ADDR16
patch((char *) csend);
#endif ADDR16
#ifdef ADDR32
patch((unsigned long) csend);
#endif ADDR32
noreach = nr;
if (goc != gocnt)
putcnt();
}
#endif OBJ