#ifndef lint
static char rcsid[] = "$Header:trees.c 12.0$";
#endif
/* $Source: /ibm/acis/usr/src/lib/mip/RCS/trees.c,v $ */
static char *sccsid ="%W% (Berkeley) %G%";
#ifdef unix
#include "mfile1.h"
#else
# include "doption h *"  /* circumvention for -D problem with preprocessor */
# include "mfile1 h *"
#endif
 
        /* corrections when in violation of lint */
 
/*  some special actions, used in finding the type of nodes */
# define NCVT 01
# define PUN 02
# define TYPL 04
# define TYPR 010
# define TYMATCH 040
# define LVAL 0100
# define CVTO 0200
# define CVTL 0400
# define CVTR 01000
# define PTMATCH 02000
# define OTHER 04000
# define NCVTR 010000
 
/* node conventions:
 
    NAME:   rval>0 is stab index for external
        rval<0 is -inlabel number
        lval is offset in bits
    ICON:   lval has the value
        rval has the STAB index, or - label number,
            if a name whose address is in the constant
        rval = NONAME means no name
    REG:    rval is reg. identification cookie
 
    */
 
int bdebug = 0;
extern ddebug;
 
#ifndef FORT
NODE *
buildtree( o, l, r ) register NODE *l, *r; {
    register NODE *p, *q;
    int actions;
    register opty;
    register struct symtab *sp;
    register NODE *lr, *ll;
    int i;
    extern int eprint();
 
# ifndef BUG1
    if( bdebug ) printf( "buildtree( %s, %o, %o )\n", opst[o], l, r );
# endif
    opty = optype(o);
 
    /* check for constants */
 
    if( opty == UTYPE && l->in.op == ICON ){
 
        switch( o ){
 
        case NOT:
            if( hflag ) werror( "constant argument to NOT" );
        case UNARY MINUS:
        case COMPL:
            if( conval( l, o, l ) ) return(l);
            break;
 
            }
        }
 
    else if( o==UNARY MINUS && l->in.op==FCON ){
        l->fpn.dval = 0 - l->fpn.dval;
        return(l);
        }
 
    else if( o==QUEST && l->in.op==ICON ) {
        l->in.op = FREE;
        r->in.op = FREE;
        if( l->tn.lval ){
            tfree( r->in.right );
            return( r->in.left );
            }
        else {
            tfree( r->in.left );
            return( r->in.right );
            }
        }
 
    else if( (o==ANDAND || o==OROR) && (l->in.op==ICON||r->in.op==ICON) ) goto ccwarn;
 
    else if( opty == BITYPE && l->in.op == ICON && r->in.op == ICON ){
 
        switch( o ){
 
        case ULT:
        case UGT:
        case ULE:
        case UGE:
        case LT:
        case GT:
        case LE:
        case GE:
        case EQ:
        case NE:
        case ANDAND:
        case OROR:
        case CBRANCH:
 
        ccwarn:
            if( hflag ) werror( "constant in conditional context" );
 
        case PLUS:
        case MINUS:
        case MUL:
        case DIV:
        case MOD:
        case AND:
        case OR:
        case ER:
        case LS:
        case RS:
            if( conval( l, o, r ) ) {
                r->in.op = FREE;
                return(l);
                }
            break;
            }
        }
 
    else if( opty == BITYPE && (l->in.op==FCON||l->in.op==ICON) &&
        (r->in.op==FCON||r->in.op==ICON) ){
        switch(o){
        case PLUS:
        case MINUS:
        case MUL:
        case DIV:
            if( l->in.op == ICON ){
                l->fpn.dval = l->tn.lval;
                }
            if( r->in.op == ICON ){
                r->fpn.dval = r->tn.lval;
                }
            l->in.op = FCON;
            l->in.type = l->fn.csiz = DOUBLE;
            r->in.op = FREE;
            switch(o){
            case PLUS:
                l->fpn.dval += r->fpn.dval;
                return(l);
            case MINUS:
                l->fpn.dval -= r->fpn.dval;
                return(l);
            case MUL:
                l->fpn.dval *= r->fpn.dval;
                return(l);
            case DIV:
                if( r->fpn.dval == 0 ) uerror( "division by 0." );
                else l->fpn.dval /= r->fpn.dval;
                return(l);
                }
            }
        }
 
    /* its real; we must make a new node */
 
    p = block( o, l, r, INT, 0, INT );

    actions = opact(p);
 
    if( actions&LVAL ){ /* check left descendent */
        if( notlval(p->in.left) ) {
            uerror( "illegal lhs of assignment operator" );
            }
        }
 
    if( actions & NCVTR ){
        p->in.left = pconvert( p->in.left );
        }
    else if( !(actions & NCVT ) ){
        switch( opty ){
 
        case BITYPE:
            p->in.right = pconvert( p->in.right );
        case UTYPE:
            p->in.left = pconvert( p->in.left );
 
            }
        }
 
    if( (actions&PUN) && (o!=CAST||cflag) ){
        chkpun(p);
        }
 
    if( actions & (TYPL|TYPR) ){
 
        q = (actions&TYPL) ? p->in.left : p->in.right;
 
        p->in.type = q->in.type;
        p->fn.cdim = q->fn.cdim;
        p->fn.csiz = q->fn.csiz;
        }
 
    if( actions & CVTL ) p = convert( p, CVTL );
    if( actions & CVTR ) p = convert( p, CVTR );
    if( actions & TYMATCH ) p = tymatch(p);
    if( actions & PTMATCH ) p = ptmatch(p);
 
    if( actions & OTHER ){
        l = p->in.left;
        r = p->in.right;
 
        switch(o){
 
        case NAME:
            sp = &stab[idname];
            if( sp->stype == UNDEF ){
#ifndef FLEXNAMES
                uerror( "%.8s undefined", sp->sname );
#else
                uerror( "%s undefined", sp->sname );
#endif
                /* make p look reasonable */
                p->in.type = p->fn.cdim = p->fn.csiz = INT;
                p->tn.rval = idname;
                p->tn.lval = 0;
                defid( p, SNULL );
                break;
                }
            p->in.type = sp->stype;
            p->fn.cdim = sp->dimoff;
            p->fn.csiz = sp->sizoff;
            p->tn.lval = 0;
            p->tn.rval = idname;
            /* special case: MOETY is really an ICON... */
            if( p->in.type == MOETY ){
                p->tn.rval = NONAME;
                p->tn.lval = sp->offset;
                p->fn.cdim = 0;
                p->in.type = ENUMTY;
                p->in.op = ICON;
                }
            break;
 
        case ICON:
            p->in.type = INT;
            p->fn.cdim = 0;
            p->fn.csiz = INT;
            break;
 
        case STRING:
            p->in.op = NAME;
            p->in.type = CHAR+ARY;
            p->tn.lval = 0;
            p->tn.rval = NOLAB;
            p->fn.cdim = curdim;
            p->fn.csiz = CHAR;
            break;
 
        case FCON:
            p->tn.lval = 0;
            p->tn.rval = 0;
            p->in.type = DOUBLE;
            p->fn.cdim = 0;
            p->fn.csiz = DOUBLE;
            break;
 
        case STREF:
            /* p->x turned into *(p+offset) */
            /* rhs must be a name; check correctness */
 
            i = r->tn.rval;
            if( i<0 || ((sp= &stab[i])->sclass != MOS && sp->sclass != MOU && !(sp->sclass&FIELD)) ){
                uerror( "member of structure or union required" );
                }else
            /* if this name is non-unique, find right one */
            if( stab[i].sflags & SNONUNIQ &&
                (l->in.type==PTR+STRTY || l->in.type == PTR+UNIONTY) &&
                (l->fn.csiz +1) >= 0 ){
                /* nonunique name && structure defined */
                char * memnam, * tabnam;
                register k;
                int j;
                int memi;
                j=dimtab[l->fn.csiz+1];
                for( ; (memi=dimtab[j]) >= 0; ++j ){
                    tabnam = stab[memi].sname;
                    memnam = stab[i].sname;
# ifndef BUG1
                    if( ddebug>1 ){
#ifndef FLEXNAMES
                        printf("member %.8s==%.8s?\n",
#else
                        printf("member %s==%s?\n",
#endif
                            memnam, tabnam);
                        }
# endif
                    if( stab[memi].sflags & SNONUNIQ ){
#ifndef FLEXNAMES
                        for( k=0; k<NCHNAM; ++k ){
                            if(*memnam++!=*tabnam)
                                goto next;
                            if(!*tabnam++) break;
                            }
#else
                        if (memnam != tabnam)
                            goto next;
#endif
                        r->tn.rval = i = memi;
                        break;
                        }
                    next: continue;
                    }
                if( memi < 0 )
#ifndef FLEXNAMES
                    uerror("illegal member use: %.8s",
#else
                    uerror("illegal member use: %s",
#endif
                        stab[i].sname);
                }
            else {
                register j;
                if( l->in.type != PTR+STRTY && l->in.type != PTR+UNIONTY ){
                    if( stab[i].sflags & SNONUNIQ ){
                        uerror( "nonunique name demands struct/union or struct/union pointer" );
                        }
                    else werror( "struct/union or struct/union pointer required" );
                    }
                else if( (j=l->fn.csiz+1)<0 ) cerror( "undefined structure or union" );
                else if( !chkstr( i, dimtab[j], DECREF(l->in.type) ) ){
#ifndef FLEXNAMES
                    werror( "illegal member use: %.8s", stab[i].sname );
#else
                    werror( "illegal member use: %s", stab[i].sname );
#endif
                    }
                }
 
            p = stref( p );
            break;
 
        case UNARY MUL:
            if( l->in.op == UNARY AND ){
                p->in.op = l->in.op = FREE;
                p = l->in.left;
                }
            if( !ISPTR(l->in.type))uerror("illegal indirection");
            p->in.type = DECREF(l->in.type);
            p->fn.cdim = l->fn.cdim;
            p->fn.csiz = l->fn.csiz;
            break;
 
       case UNARY MINUS:
            p->in.type = DOUBLE;
            p->fn.cdim = 0;
            p->fn.csiz = DOUBLE;
            p->in.left = makety(p->in.left, DOUBLE, 0, DOUBLE );
            break;

       case UNARY AND:
            switch( l->in.op ){
 
            case UNARY MUL:
	    { 
		extern int parmlbl;
                p->in.op = l->in.op = FREE;
                p = l->in.left;
/*
 * JSW - fix for apar #242
 * this if was moved above the name case.  Bad pointer references were occuring
 * because this code was sometimes being executed for the wrong case.
 * 8/21/86
 */
		if( optype(p->in.op) == BITYPE )
			{
			if (p->in.right->tn.rval== -parmlbl)
			    {
			    if (!parmadr(p)) 
				break;
			    else; /* fall through */
			    }
			else; /* fall through */
			}
            }

	    case NAME:
                p->in.type = INCREF( l->in.type );
                p->fn.cdim = l->fn.cdim;
                p->fn.csiz = l->fn.csiz;
                break;
 
            case COMOP:
                lr = buildtree( UNARY AND, l->in.right, NIL );
                p->in.op = l->in.op = FREE;
                p = buildtree( COMOP, l->in.left, lr );
                break;
 
            case QUEST:
                lr = buildtree( UNARY AND, l->in.right->in.right, NIL );
                ll = buildtree( UNARY AND, l->in.right->in.left, NIL );
                p->in.op = l->in.op = l->in.right->in.op = FREE;
                p = buildtree( QUEST, l->in.left, buildtree( COLON, ll, lr ) );
                break;
 
# ifdef ADDROREG
            case OREG:
                /* OREG was built in clocal()
                 * for an auto or formal parameter
                 * now its address is being taken
                 * local code must unwind it
                 * back to PLUS/MINUS REG ICON
                 * according to local conventions
                 */
                {
                extern NODE * addroreg();
                p->in.op = FREE;
                p = addroreg( l );
                }
                break;
 
# endif
            default:
                uerror( "unacceptable operand of &" );
                break;
                }
            break;
 
        case LS:
        case RS:
        case ASG LS:
        case ASG RS:
            if(tsize(p->in.right->in.type, p->in.right->fn.cdim, p->in.right->fn.csiz) > SZINT)
                p->in.right = makety(p->in.right, INT, 0, INT );
            break;
 
        case RETURN:
        case ASSIGN:
        case CAST:
            /* structure assignment */
            /* take the addresses of the two sides; then make an
            /* operator using STASG and
            /* the addresses of left and right */
 
            {
                register TWORD t;
                register d, s;
 
                if( l->fn.csiz != r->fn.csiz ) uerror( "assignment of different structures" );
 
                r = buildtree( UNARY AND, r, NIL );
                t = r->in.type;
                d = r->fn.cdim;
                s = r->fn.csiz;
 
                l = block( STASG, l, r, t, d, s );
 
                if( o == RETURN ){
                    p->in.op = FREE;
                    p = l;
                    break;
                    }
 
                p->in.op = UNARY MUL;
                p->in.left = l;
                p->in.right = NIL;
                break;
                }
        case COLON:
            /* structure colon */
 
            if( l->fn.csiz != r->fn.csiz ) uerror( "type clash in conditional" );
            break;
 
        case CALL:
            p->in.right = r = strargs( p->in.right );
        case UNARY CALL:
            if( !ISPTR(l->in.type)) uerror("illegal function");
            p->in.type = DECREF(l->in.type);
            if( !ISFTN(p->in.type)) uerror("illegal function");
            p->in.type = DECREF( p->in.type );
            p->fn.cdim = l->fn.cdim;
            p->fn.csiz = l->fn.csiz;
            if( l->in.op == UNARY AND && l->in.left->in.op == NAME &&
                l->in.left->tn.rval >= 0 && l->in.left->tn.rval != NONAME &&
                ( (i=stab[l->in.left->tn.rval].sclass) == FORTRAN || i==UFORTRAN ) ){
                p->in.op += (FORTCALL-CALL);
                }
            if( p->in.type == STRTY || p->in.type == UNIONTY ){
                /* function returning structure */
                /*  make function really return ptr to str., with * */
 
                p->in.op += STCALL-CALL;
                p->in.type = INCREF( p->in.type );
                p = buildtree( UNARY MUL, p, NIL );
 
                }
            break;
 
        default:
            cerror( "other code %d", o );
            }
 
        }
 
    if( actions & CVTO ) p = oconvert(p);
    p = clocal(p);
 
# ifndef BUG1
    if( bdebug ) fwalk( p, eprint, 0 );
# endif
 
    return(p);
 
    }
 
NODE *
strargs( p ) register NODE *p;  { /* rewrite structure flavored arguments */
 
    if( p->in.op == CM ){
        p->in.left = strargs( p->in.left );
        p->in.right = strargs( p->in.right );
        return( p );
        }
 
    if( p->in.type == STRTY || p->in.type == UNIONTY ){
        p = block( STARG, p, NIL, p->in.type, p->fn.cdim, p->fn.csiz );
        p->in.left = buildtree( UNARY AND, p->in.left, NIL );
        p = clocal(p);
        }
    return( p );
    }
 
chkstr( i, j, type ) register i,j; register TWORD type; {
    /* is the MOS or MOU at stab[i] OK for strict reference by a ptr */
    /* i has been checked to contain a MOS or MOU */
    /* j is the index in dimtab of the members... */
    register int k, kk;
 
    extern int ddebug;
 
# ifndef BUG1
#ifndef FLEXNAMES
    if( ddebug > 1 ) printf( "chkstr( %.8s(%d), %d )\n", stab[i].sname, i, j );
#else
    if( ddebug > 1 ) printf( "chkstr( %s(%d), %d )\n", stab[i].sname, i, j );
#endif
# endif
    if( (k = j) < 0 ) uerror( "undefined structure or union" );
    else {
        for( ; (kk = dimtab[k] ) >= 0; ++k ){
            if( kk >= SYMTSZ ){
                cerror( "gummy structure" );
                return(1);
                }
            if( kk == i ) return( 1 );
            switch( stab[kk].stype ){
 
            case STRTY:
            case UNIONTY:
                if( type == STRTY ) continue;  /* no recursive looking for strs */
                if( hflag && chkstr( i, dimtab[stab[kk].sizoff+1], stab[kk].stype ) ){
                    if( stab[kk].sname[0] == '$' ) return(0);  /* $FAKE */
                    werror(
#ifndef FLEXNAMES
                    "illegal member use: perhaps %.8s.%.8s?",
#else
                    "illegal member use: perhaps %s.%s?",
#endif
                    stab[kk].sname, stab[i].sname );
                    return(1);
                    }
                }
            }
        }
    return( 0 );
    }
 
conval( p, o, q ) register o; register NODE *p, *q; {
    /* apply the op o to the lval part of p; if binary, rhs is val */
    int i, u;
    register CONSZ val;
 
    val = q->tn.lval;
    u = ISUNSIGNED(p->in.type) || ISUNSIGNED(q->in.type);
    if( u && (o==LE||o==LT||o==GE||o==GT)) o += (UGE-GE);
 
    if( p->tn.rval != NONAME && q->tn.rval != NONAME ) return(0);
    if( q->tn.rval != NONAME && o!=PLUS ) return(0);
    if( p->tn.rval != NONAME && o!=PLUS && o!=MINUS ) return(0);
 
    switch( o ){
 
    case PLUS:
        p->tn.lval += val;
        if( p->tn.rval == NONAME ){
            p->tn.rval = q->tn.rval;
            p->in.type = q->in.type;
            }
        break;
    case MINUS:
        p->tn.lval -= val;
        break;
    case MUL:
        p->tn.lval *= val;
        break;
    case DIV:
        if( val == 0 ) uerror( "division by 0" );
        else p->tn.lval /= val;
        break;
    case MOD:
        if( val == 0 ) uerror( "division by 0" );
        else p->tn.lval %= val;
        break;
    case AND:
        p->tn.lval &= val;
        break;
    case OR:
        p->tn.lval |= val;
        break;
    case ER:
        p->tn.lval ^=  val;
        break;
    case LS:
        i = val;
        p->tn.lval = p->tn.lval << i;
        break;
    case RS:
        i = val;
        p->tn.lval = p->tn.lval >> i;
        break;
 
    case UNARY MINUS:
        p->tn.lval = - p->tn.lval;
        break;
    case COMPL:
        p->tn.lval = ~p->tn.lval;
        break;
    case NOT:
        p->tn.lval = !p->tn.lval;
        break;
    case LT:
        p->tn.lval = p->tn.lval < val;
        break;
    case LE:
        p->tn.lval = p->tn.lval <= val;
        break;
    case GT:
        p->tn.lval = p->tn.lval > val;
        break;
    case GE:
        p->tn.lval = p->tn.lval >= val;
        break;
    case ULT:
        p->tn.lval = (p->tn.lval-val)<0;
        break;
    case ULE:
        p->tn.lval = (p->tn.lval-val)<=0;
        break;
    case UGE:
        p->tn.lval = (p->tn.lval-val)>=0;
        break;
    case UGT:
        p->tn.lval = (p->tn.lval-val)>0;
        break;
    case EQ:
        p->tn.lval = p->tn.lval == val;
        break;
    case NE:
        p->tn.lval = p->tn.lval != val;
        break;
    default:
        return(0);
        }
    return(1);
    }
 
chkpun(p) register NODE *p; {
 
    /* checks p for the existance of a pun */
 
    /* this is called when the op of p is ASSIGN, RETURN, CAST, COLON, or relational */
 
    /* one case is when enumerations are used: this applies only to lint */
    /* in the other case, one operand is a pointer, the other integer type */
    /* we check that this integer is in fact a constant zero... */
 
    /* in the case of ASSIGN, any assignment of pointer to integer is illegal */
    /* this falls out, because the LHS is never 0 */
 
    register NODE *q;
    register t1, t2;
    register d1, d2;
 
    t1 = p->in.left->in.type;
    t2 = p->in.right->in.type;
 
    if( t1==ENUMTY || t2==ENUMTY ) { /* check for enumerations */
        if( logop( p->in.op ) && p->in.op != EQ && p->in.op != NE ) {
            uerror( "illegal comparison of enums" );
            return;
            }
        if( t1==ENUMTY && t2==ENUMTY && p->in.left->fn.csiz==p->in.right->fn.csiz ) return;
        werror( "enumeration type clash, operator %s", opst[p->in.op] );
        return;
        }
 
    if( ISPTR(t1) || ISARY(t1) ) q = p->in.right;
    else q = p->in.left;
 
    if( !ISPTR(q->in.type) && !ISARY(q->in.type) ){
        if( q->in.op != ICON || q->tn.lval != 0 ){
            werror( "illegal combination of pointer and integer, op %s",
                opst[p->in.op] );
            }
        }
    else {
        d1 = p->in.left->fn.cdim;
        d2 = p->in.right->fn.cdim;
        for( ;; ){
            if( t1 == t2 ) {;
                if( p->in.left->fn.csiz != p->in.right->fn.csiz ) {
                    werror( "illegal structure pointer combination" );
                    }
                return;
                }
            if( ISARY(t1) || ISPTR(t1) ){
                if( !ISARY(t2) && !ISPTR(t2) ) break;
                if( ISARY(t1) && ISARY(t2) && dimtab[d1] != dimtab[d2] ){
                    werror( "illegal array size combination" );
                    return;
                    }
                if( ISARY(t1) ) ++d1;
                if( ISARY(t2) ) ++d2;
                }
            else break;
            t1 = DECREF(t1);
            t2 = DECREF(t2);
            }
        werror( "illegal pointer combination" );
        }
 
    }
 
NODE *
stref( p ) register NODE *p; {
 
    TWORD t;
    register int d, s, dsc;
    int	     align = 0;
    register OFFSZ off;
    register struct symtab *q;
 
    /* make p->x */
    /* this is also used to reference automatic variables */
 
    q = &stab[p->in.right->tn.rval];
 
/*    if( q->sclass & FIELD )  /* added 8/84 by JEC for ibm032 */
/*      q->stype = UNSIGNED; */
 
    p->in.right->in.op = FREE;
    p->in.op = FREE;
    p = pconvert( p->in.left );
 
    /* make p look like ptr to x */
 
    if( !ISPTR(p->in.type)){
        p->in.type = PTR+UNIONTY;
        }
 
    t = INCREF( q->stype );
    d = q->dimoff;
    s = q->sizoff;
 
    p = makety( p, t, d, s );
 
    /* compute the offset to be added */
 
    off = q->offset;
    dsc = q->sclass;
 
    if( dsc & FIELD ) {  /* normalize offset */
	switch( BTYPE( t ) ) {
	case CHAR:
	case UCHAR:
	    align = ALCHAR;
	    s = CHAR;
	    break;
	case SHORT:
	case USHORT:
	    align = ALSHORT;
	    s = SHORT;
	    break;
	default:
            align = ALINT;
	    s = INT;
	    break;
	    }
        off = (off/align)*align;
        }
    if( off != 0 ) 
	p = clocal( block( PLUS, p, offcon( off, t, d, s ), t, d, s ) );
 
    p = buildtree( UNARY MUL, p, NIL );
 
    /* if field, build field info */
 
    if( dsc & FIELD ){
        p = block( FLD, p, NIL, q->stype, 0, q->sizoff );
        p->tn.rval = PKFIELD( dsc&FLDSIZ, q->offset%align );
        }
 
    return( clocal(p) );
    }
 
notlval(p) register NODE *p; {
 
    /* return 0 if p an lvalue, 1 otherwise */
 
    again:
 
    switch( p->in.op ){
 
    case FLD:
        p = p->in.left;
        goto again;
 
    case UNARY MUL:
        /* fix the &(a=b) bug, given that a and b are structures */
        if( p->in.left->in.op == STASG ) return( 1 );
        /* and the f().a bug, given that f returns a structure */
        if( p->in.left->in.op == UNARY STCALL ||
            p->in.left->in.op == STCALL ) return( 1 );
    case NAME:
    case OREG:
        if( ISARY(p->in.type) || ISFTN(p->in.type) ) return(1);
    case REG:
        return(0);
 
    default:
        return(1);
 
        }
 
    }
 
NODE *
bcon( i ) register i; { /* make a constant node with value i */
    register NODE *p;
 
    p = block( ICON, NIL, NIL, INT, 0, INT );
    p->tn.lval = i;
    p->tn.rval = NONAME;
    return( clocal(p) );
    }
 
NODE *
bpsize(p) register NODE *p; {
    return( offcon( psize(p), p->in.type, p->fn.cdim, p->fn.csiz ) );
    }
 
OFFSZ
psize( p ) register NODE *p; {
    /* p is a node of type pointer; psize returns the
       size of the thing pointed to */
 
    if( !ISPTR(p->in.type) ){
        uerror( "pointer required");
        return( SZINT );
        }
    /* note: no pointers to fields */
    return( tsize( DECREF(p->in.type), p->fn.cdim, p->fn.csiz ) );
    }
 
NODE *
convert( p, f )  register NODE *p; {
    /*  convert an operand of p
        f is either CVTL or CVTR
        operand has type int, and is converted by the size of the other side
        */
 
    register NODE *q, *r;
 
    q = (f==CVTL)?p->in.left:p->in.right;
 
    r = block( PMCONV,
        q, bpsize(f==CVTL?p->in.right:p->in.left), INT, 0, INT );
    r = clocal(r);
    if( f == CVTL )
        p->in.left = r;
    else
        p->in.right = r;
    return(p);
 
    }
#else /* FORT */
ctype( type ){

    switch( BTYPE( type ) ){

	case LONG:
	    MODTYPE( type,INT );
	    break;

	case ULONG:
	    MODTYPE( type,UNSIGNED );
    }
    return( type);
}

#endif /* FORT */
econvert( p ) register NODE *p; {
 
    /* change enums to ints, or appropriate types */
 
    register TWORD ty;
 
    if( (ty=BTYPE(p->in.type)) == ENUMTY || ty == MOETY ) {
        if( dimtab[ p->fn.csiz ] == SZCHAR ) ty = CHAR;
        else if( dimtab[ p->fn.csiz ] == SZINT ) ty = INT;
        else if( dimtab[ p->fn.csiz ] == SZSHORT ) ty = SHORT;
        else ty = LONG;
        ty = ctype( ty );
        p->fn.csiz = ty;
        MODTYPE(p->in.type,ty);
        if( p->in.op == ICON && ty != LONG ) p->in.type = p->fn.csiz = INT;
        }
    }

#ifndef FORT 
NODE *
pconvert( p ) register NODE *p; {
 
    /* if p should be changed into a pointer, do so */
 
    if( ISARY( p->in.type) ){
        p->in.type = DECREF( p->in.type );
        ++p->fn.cdim;
        return( buildtree( UNARY AND, p, NIL ) );
        }
    if( ISFTN( p->in.type) )
        return( buildtree( UNARY AND, p, NIL ) );
 
    return( p );
    }
 
NODE *
oconvert(p) register NODE *p; {
    /* convert the result itself: used for pointer and unsigned */
 
    switch(p->in.op) {
 
    case LE:
    case LT:
    case GE:
    case GT:
        if( ISUNSIGNED(p->in.left->in.type) || ISUNSIGNED(p->in.right->in.type) )  p->in.op += (ULE-LE);
    case EQ:
    case NE:
        return( p );
 
    case MINUS:
        return(  clocal( block( PVCONV,
            p, bpsize(p->in.left), INT, 0, INT ) ) );
        }
 
    cerror( "illegal oconvert: %d", p->in.op );
 
    return(p);
    }
 
NODE *
ptmatch(p)  register NODE *p; {
 
    /* makes the operands of p agree; they are
       either pointers or integers, by this time */
    /* with MINUS, the sizes must be the same */
    /* with COLON, the types must be the same */
 
    register TWORD t1, t2, t;
    register int d2, d;
    int o, s2, s;
 
    o = p->in.op;
    t = t1 = p->in.left->in.type;
    t2 = p->in.right->in.type;
    d = p->in.left->fn.cdim;
    d2 = p->in.right->fn.cdim;
    s = p->in.left->fn.csiz;
    s2 = p->in.right->fn.csiz;
 
    switch( o ){
 
    case ASSIGN:
    case RETURN:
    case CAST:
        {  break; }
 
    case MINUS:
        {  if( psize(p->in.left) != psize(p->in.right) ){
            uerror( "illegal pointer subtraction");
            }
           break;
           }
    case COLON:
        {  if( t1 != t2 ) uerror( "illegal types in :");
           break;
           }
    default:  /* must work harder: relationals or comparisons */
 
        if( !ISPTR(t1) ){
            t = t2;
            d = d2;
            s = s2;
            break;
            }
        if( !ISPTR(t2) ){
            break;
            }
 
        /* both are pointers */
        if( talign(t2,s2) < talign(t,s) ){
            t = t2;
            s = s2;
            }
        break;
        }
 
    p->in.left = makety( p->in.left, t, d, s );
    p->in.right = makety( p->in.right, t, d, s );
    if( o!=MINUS && !logop(o) ){
 
        p->in.type = t;
        p->fn.cdim = d;
        p->fn.csiz = s;
        }
 
    return(clocal(p));
    }
 
int tdebug = 0;
 
NODE *
tymatch(p)  register NODE *p; {
 
    /* satisfy the types of various arithmetic binary ops */
 
    /* rules are:
        if assignment, op, type of LHS
        if any float or doubles, make double
        if any longs, make long
        otherwise, make int
        if either operand is unsigned, the result is...
    */
 
    register TWORD t1, t2, t, tu;
    register o, u;
 
    o = p->in.op;
    t1 = p->in.left->in.type;
    t2 = p->in.right->in.type;
    if( (t1==UNDEF || t2==UNDEF) && o!=CAST )
        uerror("void type illegal in expression");
 
    u = 0;
    if( ISUNSIGNED(t1) ){
        u = 1;
        t1 = DEUNSIGN(t1);
        }
    if( ISUNSIGNED(t2) ){
        u = 1;
        t2 = DEUNSIGN(t2);
        }
 
    if( ( t1 == CHAR || t1 == SHORT ) && o!= RETURN ) t1 = INT;
    if( t2 == CHAR || t2 == SHORT ) t2 = INT;
 
    if( t1==DOUBLE || t1==FLOAT || t2==DOUBLE || t2==FLOAT ) t = DOUBLE;
    else if( t1==LONG || t2==LONG ) t = LONG;
    else t = INT;

#ifdef FLOAT_IS_FLOAT 
    if( asgop(o) ){
#else
    if ( o==RETURN && t1==FLOAT ) {
	t= t1= tu = DOUBLE;
    }
    else if ( asgop(o) ) {
#endif FLOAT_IS_FLOAT
        tu = p->in.left->in.type;
        t = t1;
        }
    else {
        tu = (u && UNSIGNABLE(t))?ENUNSIGN(t):t;
        }
 
    /* because expressions have values that are at least as wide
       as INT or UNSIGNED, the only conversions needed
       are those involving FLOAT/DOUBLE, and those
       from LONG to INT and ULONG to UNSIGNED */
 
    if( t != t1 ) p->in.left = makety( p->in.left, tu, 0, (int)tu );
 
    if( t != t2 || o==CAST ) p->in.right = makety( p->in.right, tu, 0, (int)tu );
 
    if( asgop(o) ){
        p->in.type = p->in.left->in.type;
        p->fn.cdim = p->in.left->fn.cdim;
        p->fn.csiz = p->in.left->fn.csiz;
        }
    else if( !logop(o) ){
        p->in.type = tu;
        p->fn.cdim = 0;
        p->fn.csiz = t;
        }
 
# ifndef BUG1
    if( tdebug ) printf( "tymatch(%o): %o %s %o => %o\n",p,t1,opst[o],t2,tu );
# endif
 
    return(p);
    }
#endif /* ndef FORT */ 

NODE *
makety( p, t, d, s ) register NODE *p; register TWORD t; register d,s; {
    /* make p into type t by inserting a conversion */
 
    if( p->in.type == ENUMTY && p->in.op == ICON ) econvert(p);
    if( t == p->in.type ){
        p->fn.cdim = d;
        p->fn.csiz = s;
        return( p );
        }
 
    if( t & TMASK ){
        /* non-simple type */
        return( block( PCONV, p, NIL, t, d, s ) );
        }
 
    if( p->in.op == ICON ){
        if( t==DOUBLE||t==FLOAT ){
            p->in.op = FCON;
            if( ISUNSIGNED(p->in.type) ){
                p->fpn.dval = /* (unsigned CONSZ) */ p->tn.lval;
                }
            else {
                p->fpn.dval = p->tn.lval;
                }
 
            p->in.type = p->fn.csiz = DOUBLE;
            return( block( SCONV, p, NIL, t, d, s ) );
            }
        }
 
    return( block( SCONV, p, NIL, t, d, s ) );
 
    }
 
NODE *
block( o, l, r, t, d, s ) register NODE *l, *r; register TWORD t; register d,s; {
 
    register NODE *p;
 
    p = talloc();
    p->in.op = o;
    p->in.left = l;
    p->in.right = r;
    p->in.type = t;
    p->fn.cdim = d;
    p->fn.csiz = s;
    return(p);
    }

#ifndef FORT 
icons(p) register NODE *p; {
    /* if p is an integer constant, return its value */
    register int val;
 
    if( p->in.op != ICON ){
        uerror( "constant expected");
        val = 1;
        }
    else {
        val = p->tn.lval;
        if( val != p->tn.lval ) uerror( "constant too big for cross-compiler" );
        }
    tfree( p );
    return(val);
    }
 
/*  the intent of this table is to examine the
    operators, and to check them for
    correctness.
 
    The table is searched for the op and the
    modified type (where this is one of the
    types INT (includes char and short), LONG,
    DOUBLE (includes FLOAT), and POINTER
 
    The default action is to make the node type integer
 
    The actions taken include:
        PUN   check for puns
        CVTL      convert the left operand
        CVTR      convert the right operand
        TYPL      the type is determined by the left operand
        TYPR      the type is determined by the right operand
        TYMATCH   force type of left and right to match, by inserting conversions
        PTMATCH   like TYMATCH, but for pointers
        LVAL      left operand must be lval
        CVTO      convert the op
        NCVT      do not convert the operands
        OTHER     handled by code
        NCVTR     convert the left operand, not the right...
 
    */
 
# define MINT 01  /* integer */
# define MDBI 02   /* integer or double */
# define MSTR 04  /* structure */
# define MPTR 010  /* pointer */
# define MPTI 020  /* pointer or integer */
# define MENU 040 /* enumeration variable or member */
 
opact( p )  register NODE *p; {
 
    register mt12, mt1, mt2, o;
 
    mt12 = 0;
 
    switch( optype(o=p->in.op) ){
 
    case BITYPE:
        mt12=mt2 = moditype( p->in.right->in.type );
    case UTYPE:
        mt12 &= (mt1 = moditype( p->in.left->in.type ));
 
        }
 
    switch( o ){
 
    case NAME :
    case STRING :
    case ICON :
    case FCON :
    case CALL :
    case UNARY CALL:
    case UNARY MUL:
        {  return( OTHER ); }
    case UNARY MINUS:
	if( mt1 == MDBI ) return( OTHER );
        else if( mt1 & MINT ) return( TYPL );
        break;
 
    case COMPL:
        if( mt1 & MINT ) return( TYPL );
        break;
 
    case UNARY AND:
        {  return( NCVT+OTHER ); }
    case INIT:
    case CM:
    case NOT:
    case CBRANCH:
    case ANDAND:
    case OROR:
        return( 0 );
 
    case MUL:
    case DIV:
        if( mt12 & MDBI ) return( TYMATCH );
        break;
 
    case MOD:
    case AND:
    case OR:
    case ER:
        if( mt12 & MINT ) return( TYMATCH );
        break;
 
    case LS:
    case RS:
        if( mt12 & MINT ) return( TYMATCH+OTHER );
        break;
 
    case EQ:
    case NE:
    case LT:
    case LE:
    case GT:
    case GE:
        if( (mt1&MENU)||(mt2&MENU) ) return( PTMATCH+PUN+NCVT );
        if( mt12 & MDBI ) return( TYMATCH+CVTO );
        else if( mt12 & MPTR ) return( PTMATCH+PUN );
        else if( mt12 & MPTI ) return( PTMATCH+PUN );
        else break;
 
    case QUEST:
    case COMOP:
        if( mt2&MENU ) return( TYPR+NCVTR );
        return( TYPR );
 
    case STREF:
        return( NCVTR+OTHER );
 
    case FORCE:
        return( TYPL );
 
    case COLON:
        if( mt12 & MENU ) return( NCVT+PUN+PTMATCH );
        else if( mt12 & MDBI ) return( TYMATCH );
        else if( mt12 & MPTR ) return( TYPL+PTMATCH+PUN );
        else if( (mt1&MINT) && (mt2&MPTR) ) return( TYPR+PUN );
        else if( (mt1&MPTR) && (mt2&MINT) ) return( TYPL+PUN );
        else if( mt12 & MSTR ) return( NCVT+TYPL+OTHER );
        break;
 
    case ASSIGN:
    case RETURN:
        if( mt12 & MSTR ) return( LVAL+NCVT+TYPL+OTHER );
    case CAST:
        if(o==CAST && mt1==0)return(TYPL+TYMATCH);
        if( mt12 & MDBI ) return( TYPL+LVAL+TYMATCH );
        else if( (mt1&MENU)||(mt2&MENU) ) return( LVAL+NCVT+TYPL+PTMATCH+PUN );
/*
        else if( mt12 == 0 ) break;
*/
	/* JSW fix for Rice Univ. apar */
 	/* if right is TVOID and looks like a CALL, is not ok */
 	else if (mt2 == 0 && (p->in.right->in.op == CALL || p->in.right->in.op == UNARY CALL))
 		break;

        else if( mt1 & MPTR ) return( LVAL+PTMATCH+PUN );
        else if( mt12 & MPTI ) return( TYPL+LVAL+TYMATCH+PUN );
        break;
 
    case ASG LS:
    case ASG RS:
        if( mt12 & MINT ) return( TYPL+LVAL+OTHER );
        break;
 
    case ASG MUL:
    case ASG DIV:
        if( mt12 & MDBI ) return( LVAL+TYMATCH );
        break;
 
    case ASG MOD:
    case ASG AND:
    case ASG OR:
    case ASG ER:
        if( mt12 & MINT ) return( LVAL+TYMATCH );
        break;
 
    case ASG PLUS:
    case ASG MINUS:
    case INCR:
    case DECR:
        if( mt12 & MDBI ) return( TYMATCH+LVAL );
        else if( (mt1&MPTR) && (mt2&MINT) ) return( TYPL+LVAL+CVTR );
        break;
 
    case MINUS:
        if( mt12 & MPTR ) return( CVTO+PTMATCH+PUN );
        if( mt2 & MPTR ) break;
    case PLUS:
        if( mt12 & MDBI ) return( TYMATCH );
        else if( (mt1&MPTR) && (mt2&MINT) ) return( TYPL+CVTR );
        else if( (mt1&MINT) && (mt2&MPTR) ) return( TYPR+CVTL );
 
        }
    uerror( "operands of %s have incompatible types", opst[o] );
    return( NCVT );
    }
 
moditype( ty ) register TWORD ty; {
 
    switch( ty ){
 
    case TVOID:
    case UNDEF:
        return(0); /* type is void */
    case ENUMTY:
    case MOETY:
        return( MENU );
 
    case STRTY:
    case UNIONTY:
        return( MSTR );
 
    case CHAR:
    case SHORT:
    case UCHAR:
    case USHORT:
        return( MINT|MPTI|MDBI );
    case UNSIGNED:
    case ULONG:
    case INT:
    case LONG:
        return( MINT|MDBI|MPTI );
    case FLOAT:
    case DOUBLE:
        return( MDBI );
    default:
        return( MPTR|MPTI );
 
        }
    }
 
NODE *
doszof( p )  register NODE *p; {
    /* do sizeof p */
    register int i;
 
    /* whatever is the meaning of this if it is a bitfield? */
    i = tsize( p->in.type, p->fn.cdim, p->fn.csiz )/SZCHAR;
 
    tfree(p);
    if( i <= 0 ) werror( "sizeof returns 0" );
    return( bcon( i ) );
    }
 
# ifndef BUG2
eprint( p, down, a, b ) register NODE *p; register int *a, *b; {
    register ty;
 
    *a = *b = down+1;
    while( down > 1 ){
/*      printf( "\t" );   modified 1/19/84 by JEC
*/      printf( "    " );
        down -= 2;
        }
    if( down ) printf( "    " );
 
    ty = optype( p->in.op );
 
    printf("%o) %s, ", p, opst[p->in.op] );
    if( ty == LTYPE ){
        printf( CONFMT, p->tn.lval );
        printf( ", %d, ", p->tn.rval );
        }
    tprint( p->in.type );
    printf( ", %d, %d\n", p->fn.cdim, p->fn.csiz );
    }
# endif
 
prtdcon( p ) register NODE *p; {
    register int i;
 
    if( p->in.op == FCON ){
        locctr( DATA );
        defalign( ALDOUBLE );
        deflab( i = getlab() );
        fincode( p->fpn.dval, SZDOUBLE );
        p->tn.lval = 0;
        p->tn.rval = -i;
#ifdef ONEPASS
#ifdef FLEXNAMES
	p->in.name= "";
#else
too bad
#endif FLEXNAMES
#endif ONEPASS
        p->in.type = DOUBLE;
        p->in.op = NAME;
        }
    }
 
 
int edebug = 0;
ecomp( p ) register NODE *p; {
# ifndef BUG2
    if( edebug ) fwalk( p, eprint, 0 );
# endif
    if( !reached ){
        werror( "statement not reached" );
        reached = 1;
        }
    p = optim(p);
    walkf( p, prtdcon );
    locctr( PROG );
    ecode( p );
    tfree(p);
    }
 
# ifdef STDPRTREE
# ifndef ONEPASS
 
prtree(p) register NODE *p; {
 
    register struct symtab *q;
    register ty;
 
# ifdef MYPRTREE
    MYPRTREE(p);  /* local action can be taken here; then return... */
#endif
 
    ty = optype(p->in.op);
 
/*  printf( "%d\t", p->in.op );  modified 1/20/84 by JEC
*/  printf( "\n| %d\t", p->in.op );
 
    if( ty == LTYPE ) {
        printf( CONFMT, p->tn.lval );
        printf( "\t" );
        }
    if( ty != BITYPE ) {
        if( p->in.op == NAME || p->in.op == ICON ) printf( "0\t" );
        else printf( "%d\t", p->tn.rval );
        }
 
    printf( "%o\t", p->in.type );
 
    /* handle special cases */
 
    switch( p->in.op ){
 
    case NAME:
    case ICON:
        /* print external name */
        if( p->tn.rval == NONAME ) printf( "\n" );
        else if( p->tn.rval >= 0 ){
            q = &stab[p->tn.rval];
            printf(  "%s\n", exname(q->sname) );
            }
        else { 
            char temp[32];

	    if ((p->in.op==NAME && p->in.type!=DOUBLE && p->in.type!=FLOAT) ||
		(p->in.op==ICON && p->tn.rval<0)) {
		if ( strncmp( "LCOM", p->in.name, 4) != 0 ) {
		     sprintf(temp, LABFMT, -p->tn.rval );
		     p->in.name = tstr(temp);
		}
	    } else { /* label */
                sprintf( temp, LABFMT, -p->tn.rval );
                p->in.name = tstr(temp);
	    }
        break;
 
    case STARG:
    case STASG:
    case STCALL:
    case UNARY STCALL:
        /* print out size */
        /* use lhs size, in order to avoid hassles with the structure `.' operator */
 
        /* note: p->in.left not a field... */
        printf( CONFMT, (CONSZ) tsize( STRTY, p->in.left->fn.cdim, p->in.left->fn.csiz ) );
        printf( "\t%d\t\n", talign( STRTY, p->in.left->fn.csiz ) );
        break;
 
    default:
        printf(  "\n" );
        }
 
    if( ty != LTYPE ) prtree( p->in.left );
    if( ty == BITYPE ) prtree( p->in.right );
 
    }
 
# else
 
p2tree(p) register NODE *p; {
    register ty;
 
# ifdef MYP2TREE
    MYP2TREE(p);  /* local action can be taken here; then return... */
# endif
 
    ty = optype(p->in.op);
 
    switch( p->in.op ){
 
    case NAME:
    case ICON:
#ifndef FLEXNAMES
        if( p->tn.rval == NONAME ) p->in.name[0] = '\0';
#else
        if( p->tn.rval == NONAME ) p->in.name = "";
#endif
        else if( p->tn.rval >= 0 ){ /* copy name from exname */
            register char *cp;
            register i;
            cp = exname( stab[p->tn.rval].sname );
#ifndef FLEXNAMES
            for( i=0; i<NCHNAM; ++i ) p->in.name[i] = *cp++;
#else
            p->in.name = tstr(cp);
#endif
            }
#ifndef FLEXNAMES
        else sprintf( p->in.name, LABFMT, -p->tn.rval );
#else
        else {
            char temp[32];

	    if ((p->in.op==NAME)||(p->in.op==ICON && p->tn.rval<0)) {
		if ( strncmp( "LCOM", p->in.name, 4) != 0 ) {
		     sprintf(temp, LABFMT, -p->tn.rval );
		     p->in.name = tstr(temp);
		}
	    } else {
                sprintf( temp, LABFMT, -p->tn.rval );
                p->in.name = tstr(temp);
	    }
        }
#endif
        break;
 
    case STARG:
    case STASG:
    case STCALL:
    case UNARY STCALL:
        /* set up size parameters */
        p->stn.stsize = (tsize(STRTY,p->in.left->fn.cdim,p->in.left->fn.csiz)+SZCHAR-1)/SZCHAR;
        p->stn.stalign = talign(STRTY,p->in.left->fn.csiz)/SZCHAR;
        break;
 
    case REG:
        rbusy( p->tn.rval, p->in.type );
    default:
#ifndef FLEXNAMES
        p->in.name[0] = '\0';
#else
        p->in.name = "";
#endif
        }
 
    p->in.rall = NOPREF;
 
    if( ty != LTYPE ) p2tree( p->in.left );
    if( ty == BITYPE ) p2tree( p->in.right );
    }
 
# endif
# endif
# endif
