usr/src/ucb/pascal/pdx/tree/assign.c

/*
 * Copyright (c) 1980 Regents of the University of California.
 * All rights reserved.  The Berkeley software License Agreement
 * specifies the terms and conditions for redistribution.
 */

#ifndef lint
static char sccsid[] = "@(#)assign.c    5.1 (Berkeley) 6/6/85";
#endif not lint

/*
 * assign the value of an expression to a variable (or term)
 */

#include "defs.h"
#include "tree.h"
#include "sym.h"
#include "process.h"
#include "tree.rep"

assign(var, exp)
NODE *var;
NODE *exp;
{
        ADDRESS addr;
        int varsize;
        char cvalue;
        short svalue;
        long lvalue;

        if (!compatible(var->nodetype, exp->nodetype)) {
                error("incompatible types");
        }
        addr = lval(var);
        eval(exp);
        varsize = size(var->nodetype);
        if (varsize < sizeof(long)) {
                lvalue = pop(long);
                switch (varsize) {
                        case sizeof(char):
                                cvalue = lvalue;
                                dwrite(&cvalue, addr, varsize);
                                break;

                        case sizeof(short):
                                svalue = lvalue;
                                dwrite(&svalue, addr, varsize);
                                break;

                        default:
                                panic("bad size %d", varsize);
                }
        } else {
                sp -= varsize;
                dwrite(sp, addr, varsize);
        }
}