pftn.c

<B>Digital的Unix操作系统VAX 4.2源码</B>

 			SETOFF( argoff, ALSTACK );	/* slr001 restore alignment */

		}
	cendarg();
	locctr(PROG);
	defalign(ALINT);
	ftnno = getlab();
	bfcode( paramstk, paramno );
	paramno = 0;
	}

NODE *
rstruct( idn, soru, typattr ){ /* reference to a structure or union, 
				  with no definition */
	register struct symtab *p;
	register NODE *q;
	p = &stab[idn];
	switch( p->stype ){

	case UNDEF:
	def:
		q = block( FREE, NIL, NIL, 0, 0, 0 );
		q->tn.rval = idn;
		q->in.type = (soru&INSTRUCT) ? STRTY : ( (soru&INUNION) ? UNIONTY : ENUMTY );
		q->in.typattr = typattr;
		defid( q, (soru&INSTRUCT) ? STNAME : ( (soru&INUNION) ? UNAME : ENAME ) );
		break;

	case STRTY:
		if( soru & INSTRUCT ) break;
		goto def;

	case UNIONTY:
		if( soru & INUNION ) break;
		goto def;

	case ENUMTY:
		if( !(soru&(INUNION|INSTRUCT)) ) break;
		goto def;

		}
	stwart = instruct;
	return( mkty( p->stype, 0, p->sizoff ) );
	}

moedef( idn ){
	register NODE *q;

	q = block( FREE, NIL, NIL, MOETY, 0, 0 );
	q->tn.rval = idn;
	if( idn>=0 ) defid( q, MOE );
	}

bstruct( idn, soru, typattr ){ /* begining of structure/union declaration */
	register NODE *q;

	psave( instruct );
	psave( typattr );
	psave( curclass );
	psave( strucoff );
	strucoff = 0;
	instruct = soru;
	q = block( FREE, NIL, NIL, 0, 0, 0 );
	q->tn.rval = idn;
	if( instruct==INSTRUCT ){
		curclass = MOS;
		q->in.type = STRTY;
		if( idn >= 0 ) defid( q, STNAME );
		}
	else if( instruct == INUNION ) {
		curclass = MOU;
		q->in.type = UNIONTY;
		if( idn >= 0 ) defid( q, UNAME );
		}
	else { /* enum */
		curclass = MOE;
		q->in.type = ENUMTY;
		if( idn >= 0 ) defid( q, ENAME );
		}
	psave( idn = q->tn.rval );
	/* the "real" definition is where the members are seen */
	if ( idn >= 0 ) {
	    stab[idn].suse = lineno;
	    stab[idn].stypattr = typattr;
	}
	return( paramno-5 );
	}

NODE *
dclstruct( oparam ){
	register struct symtab *p;
	register i, al, sa, j, sz, szindex;
	register TWORD temp, typattr;
	register high, low;

	/* paramstack contains:
		paramstack[ oparam ] = previous instruct
		paramstack[ oparam+1 ] = type attributes
		paramstack[ oparam+2 ] = previous class
		paramstk[ oparam+3 ] = previous strucoff
		paramstk[ oparam+4 ] = structure name

		paramstk[ oparam+5, ... ]  = member stab indices

		*/


	if( (i=paramstk[oparam+4]) < 0 ){
		szindex = curdim;
		dstash( 0 );  /* size */
		dstash( -1 );  /* index to member names */
		dstash( ALSTRUCT );  /* alignment */
		dstash( -lineno );	/* name of structure */
		}
	else {
		szindex = stab[i].sizoff;
		}

# ifndef BUG1
	if( ddebug ){
#ifndef FLEXNAMES
		printf( "dclstruct( %.8s ), szindex = %d\n", (i>=0)? stab[i].sname : "??", szindex );
#else
		printf( "dclstruct( %s ), szindex = %d\n", (i>=0)? stab[i].sname : "??", szindex );
#endif
		}
# endif
	temp = (instruct&INSTRUCT)?STRTY:((instruct&INUNION)?UNIONTY:ENUMTY);
	stwart = instruct = paramstk[ oparam ];
	typattr = paramstk[oparam+1];
	curclass = paramstk[ oparam+2 ];
	dimtab[ szindex+1 ] = curdim;
	al = ALSTRUCT;

	high = low = 0;

	for( i = oparam+5;  i< paramno; ++i ){
		dstash( j=paramstk[i] );
		if( j<0 || j>= SYMTSZ ) cerror( "gummy structure member" );
		p = &stab[j];
		p->stypattr |= typattr;
		if( temp == ENUMTY ){
			if( p->offset < low ) low = p->offset;
			if( p->offset > high ) high = p->offset;
			p->sizoff = szindex;
			continue;
			}
		sa = talign( p->stype, p->sizoff );
		if( p->sclass & FIELD ){
			sz = p->sclass&FLDSIZ;
			}
		else {
			sz = tsize( p->stype, p->dimoff, p->sizoff );
			}
		if( sz == 0 ){
#ifndef FLEXNAMES
			werror( "illegal zero sized structure member: %.8s", p->sname );
#else
			werror( "illegal zero sized structure member: %s", p->sname );
#endif
			}
		if( sz > strucoff ) strucoff = sz;  /* for use with unions */
		SETOFF( al, sa );
		/* set al, the alignment, to the lcm of the alignments of the members */
		}
	dstash( -1 );  /* endmarker */
	SETOFF( strucoff, al );

	if( temp == ENUMTY ){
		register TWORD ty;

# ifdef ENUMSIZE
		ty = ENUMSIZE(high,low);
# else
		if( (char)high == high && (char)low == low ) ty = ctype( CHAR );
		else if( (short)high == high && (short)low == low ) ty = ctype( SHORT );
		else ty = ctype(INT);
#endif
		strucoff = tsize( ty, 0, (int)ty );
		dimtab[ szindex+2 ] = al = talign( ty, (int)ty );
		}

	if( strucoff == 0 ) uerror( "zero sized structure" );
	dimtab[ szindex ] = strucoff;
	dimtab[ szindex+2 ] = al;
	dimtab[ szindex+3 ] = paramstk[ oparam+4 ];  /* name index */

	FIXSTRUCT( szindex, oparam ); /* local hook, eg. for sym debugger */
# ifndef BUG1
	if( ddebug>1 ){
		printf( "\tdimtab[%d,%d,%d] = %d,%d,%d\n", szindex,szindex+1,szindex+2,
				dimtab[szindex],dimtab[szindex+1],dimtab[szindex+2] );
		for( i = dimtab[szindex+1]; dimtab[i] >= 0; ++i ){
#ifndef FLEXNAMES
			printf( "\tmember %.8s(%d)\n", stab[dimtab[i]].sname, dimtab[i] );
#else
			printf( "\tmember %s(%d)\n", stab[dimtab[i]].sname, dimtab[i] );
#endif
			}
		}
# endif

	strucoff = paramstk[ oparam+3 ];
	paramno = oparam;

	return( mkty( temp, 0, szindex ) );
	}

	/* VARARGS */
yyerror( s ) char *s; { /* error printing routine in parser */

	uerror( s );

	}

yyaccpt(){
	ftnend();
	}

ftnarg( idn ) {
	switch( stab[idn].stype ){

	case UNDEF:
		/* this parameter, entered at scan */
		break;
	case FARG:
#ifndef FLEXNAMES
		uerror("redeclaration of formal parameter, %.8s",
#else
		uerror("redeclaration of formal parameter, %s",
#endif
			stab[idn].sname);
		/* fall thru */
	case FTN:
		/* the name of this function matches parm */
		/* fall thru */
	default:
		idn = hide( &stab[idn]);
		break;
	case TNULL:
		/* unused entry, fill it */
		;
		}
	stab[idn].stype = FARG;
	stab[idn].sclass = PARAM;
	psave( idn );
	}

talign( ty, s) register unsigned ty; register s; {
	/* compute the alignment of an object with type ty, sizeoff index s */

	register i;
	if( s<0 && ty!=INT && ty!=CHAR && ty!=SHORT && ty!=UNSIGNED && ty!=UCHAR && ty!=USHORT 
#ifdef LONGFIELDS
		&& ty!=LONG && ty!=ULONG
#endif
					){
		return( fldal( ty ) );
		}

	for( i=0; i<=(SZINT-BTSHIFT-1); i+=TSHIFT ){
		switch( (ty>>i)&TMASK ){

		case FTN:
			cerror( "compiler takes alignment of function");
		case PTR:
			return( ALPOINT );
		case ARY:
			continue;
		case 0:
			break;
			}
		}

	switch( BTYPE(ty) ){

	case UNIONTY:
	case ENUMTY:
	case STRTY:
		return( (unsigned int) dimtab[ s+2 ] );
	case CHAR:
	case UCHAR:
		return( ALCHAR );
	case FLOAT:
		return( ALFLOAT );
	case DOUBLE:
		return( ALDOUBLE );
	case LONG:
	case ULONG:
		return( ALLONG );
	case SHORT:
	case USHORT:
		return( ALSHORT );
	default:
		return( ALINT );
		}
	}

OFFSZ
tsize( ty, d, s )  TWORD ty; {
	/* compute the size associated with type ty,
	    dimoff d, and sizoff s */
	/* BETTER NOT BE CALLED WHEN t, d, and s REFER TO A BIT FIELD... */

	int i;
	OFFSZ mult;

	mult = 1;

	for( i=0; i<=(SZINT-BTSHIFT-1); i+=TSHIFT ){
		switch( (ty>>i)&TMASK ){

		case FTN:
			cerror( "compiler takes size of function");
		case PTR:
			return( SZPOINT * mult );
		case ARY:
			mult *= (unsigned int) dimtab[ d++ ];
			continue;
		case 0:
			break;

			}
		}

	if( dimtab[s]==0 ) {
		uerror( "unknown size");
		return( SZINT );
		}
	return( (unsigned int) dimtab[ s ] * mult );
	}

inforce( n ) OFFSZ n; {  /* force inoff to have the value n */
	/* inoff is updated to have the value n */
	OFFSZ wb;
	register rest;
	/* rest is used to do a lot of conversion to ints... */

	if( inoff == n ) return;
	if( inoff > n )
	{
		inoff = n;							/* make it object only once */
		werror( "attempt to initialize past end of object" );
		return;
/* was:	cerror( "initialization alignment error"); /* fix qar 4654 & 4556 */

		}

	wb = inoff;
	SETOFF( wb, SZINT );

	/* wb now has the next higher word boundary */

	if( wb >= n ){ /* in the same word */
		rest = n - inoff;
		vfdzero( rest );
		return;
		}

	/* otherwise, extend inoff to be word aligned */

	rest = wb - inoff;
	vfdzero( rest );

	/* now, skip full words until near to n */

	rest = (n-inoff)/SZINT;
	zecode( rest );

	/* now, the remainder of the last word */

	rest = n-inoff;
	vfdzero( rest );
	if( inoff != n ) cerror( "inoff error");

	}

vfdalign( n ){ /* make inoff have the offset the next alignment of n */
	OFFSZ m;

	m = inoff;
	SETOFF( m, n );
	inforce( m );
	}


int idebug = 0;

int ibseen = 0;  /* the number of } constructions which have been filled */

int iclass;  /* storage class of thing being initialized */

int ilocctr = 0;  /* location counter for current initialization */

beginit(curid){
	/* beginning of initilization; set location ctr and set type */
	register struct symtab *p;

# ifndef BUG1
	if( idebug >= 3 ) printf( "beginit(), curid = %d\n", curid );
# endif

	p = &stab[curid];

	iclass = p->sclass;
	if( curclass == EXTERN || curclass == FORTRAN ) iclass = EXTERN;
	switch( iclass ){

	case UNAME:
	case EXTERN:
		return;
	case AUTO:
	case REGISTER:
		break;
	case EXTDEF:
	case STATIC:
		if (ISRODATA(p->stypattr, p->stype)) {
		    ilocctr = RODATA;
		} else {
		    ilocctr = ISARY(p->stype)?ADATA:DATA;
		}
		locctr( ilocctr );
		defalign( talign( p->stype, p->sizoff ) );
		defnam( p );

		}

	inoff = 0;
	ibseen = 0;

	pstk = 0;

	instk( curid, p->stype, p->dimoff, p->sizoff, inoff );

	}

instk( id, t, d, s, off ) OFFSZ off; TWORD t; {
	/* make a new entry on the parameter stack to initialize id */

	register struct symtab *p;

	for(;;){
# ifndef BUG1
		if( idebug ) printf( "instk((%d, %o,%d,%d, %d)\n", id, t, d, s, off );
# endif

		/* save information on the stack */

		if( !pstk ) pstk = instack;
		else ++pstk;

		pstk->in_fl = 0;	/* { flag */
		pstk->in_id =  id ;
		pstk->in_t =  t ;
		pstk->in_d =  d ;
		pstk->in_s =  s ;
		pstk->in_n = 0;  /* number seen */
		pstk->in_x =  t==STRTY ?dimtab[s+1] : 0 ;
		pstk->in_off =  off;   /* offset at the beginning of this element */
		/* if t is an array, DECREF(t) can't be a field */
		/* INS_sz has size of array elements, and -size for fields */
		if( ISARY(t) ){
			pstk->in_sz = tsize( DECREF(t), d+1, s );
			}
		else if( stab[id].sclass & FIELD ){
			pstk->in_sz = - ( stab[id].sclass & FLDSIZ );
			}
		else {
			pstk->in_sz = 0;
			}

		if( (iclass==AUTO || iclass == REGISTER ) &&
			(ISARY(t) || t==STRTY) ) uerror( "no automatic aggregate initialization" );

		/* now, if this is not a scalar, put on another element */

		if( ISARY(t) ){
			t = DECREF(t);
			++d;
			continue;
			}
		else if( t == STRTY ){
			id = dimtab[pstk->in_x];
			p = &stab[id];
			if( p->sclass != MOS && !(p->sclass&FIELD) ) cerror( "insane structure member list" );
			t = p->stype;
			d = p->dimoff;
			s = p->sizoff;
			off += p->offset;
			continue;
			}
		else return;
		}
	}

NODE *
getstr(){ /* decide if the string is external or an initializer, and get the contents accordingly */

	register l, temp;
	register NODE *p;

	if( (iclass==EXTDEF||iclass==STATIC) && (pstk->in_t == CHAR || pstk->in_t == UCHAR) &&
			pstk!=instack && ISARY( pstk[-1].in_t ) ){
		/* treat "abc" as { 'a', 'b', 'c', 0 } */
		strflg = 1;
		ilbrace();  /* simulate { */
		inforce( pstk->in_off );
		/* if the array is inflexible (not top level), pass in the size and
			be prepared to throw away unwanted initializers */
		lxstr((pstk-1)!=instack?dimtab[(pstk-1)->in_d]:0);  /* get the contents */
		irbrace();  /* simulate } */
		return( NIL );
		}
	else { /* make a label, and get the contents and stash them away */
		if( iclass != SNULL ){ /* initializing */
			/* fill out previous word, to permit pointer */
			vfdalign( ALPOINT );
			}
		temp = locctr( blevel==0?ISTRNG:STRNG ); /* set up location counter */
		deflab( l = getlab() );
		strflg = 0;
		lxstr(0); /* get the contents */
		locctr( blevel==0?ilocctr:temp );
		p = buildtree( STRING, NIL, NIL );
		p->tn.rval = -l;
		return(p);
		}
	}

putbyte( v ){ /* simulate byte v appearing in a list of integer values */
	register NODE *p;
	p = bcon(v);
	incode( p, SZCHAR );
	tfree( p );
	gotscal();
	}

endinit(){
	register TWORD t;
	register d, s, n, d1;

# ifndef BUG1
	if( idebug ) printf( "endinit(), inoff = %d\n", inoff );
# endif

	switch( iclass ){

	case EXTERN:
	case AUTO:
	case REGISTER:
		return;
		}