582 lines
		
	
	
	
		
			12 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			582 lines
		
	
	
	
		
			12 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* D E S I G N A T O R   E V A L U A T I O N */
 | |
| 
 | |
| /*	Code generation for designators.
 | |
| 	This file contains some routines that generate code common to address
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| 	as well as value computations, and leave a description in a "desig"
 | |
| 	structure. It also contains routines to load an address, load a value
 | |
| 	or perform a store.
 | |
| */
 | |
| 
 | |
| #include	"debug.h"
 | |
| 
 | |
| #include	<assert.h>
 | |
| #include	<em.h>
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| 
 | |
| #include	"LLlex.h"
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| #include	"def.h"
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| #include	"desig.h"
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| #include	"main.h"
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| /* next line DEBUG */
 | |
| #include	"idf.h"
 | |
| #include	"node.h"
 | |
| #include	"scope.h"
 | |
| #include	"type.h"
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| 
 | |
| struct desig	InitDesig = {DSG_INIT, 0, 0, NULLDEF, 0};
 | |
| struct withdesig *WithDesigs;
 | |
| 
 | |
| 
 | |
| STATIC int
 | |
| properly(ds, size, al)
 | |
| 	register struct desig *ds;
 | |
| 	arith size;
 | |
| {
 | |
| 	/*	Check if it is allowed to load or store the value indicated
 | |
| 		by "ds" with LOI/STI.
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| 		- if the size is not either a multiple or a dividor of the
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| 		  wordsize, then not.
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| 		- if the alignment is at least "word" then OK.
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| 		- if size is dividor of word_size and alignment >= size then OK.
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| 		- otherwise check alignment of address. This can only be done
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| 		  with DSG_FIXED.
 | |
| 	*/
 | |
| 
 | |
| 	arith szmodword = size % word_size;	/* 0 if multiple of wordsize */
 | |
| 	arith wordmodsz = word_size % size;	/* 0 if dividor of wordsize */
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| 
 | |
| 	if( szmodword && wordmodsz ) return 0;
 | |
| 	if( al >= word_align ) return 1;
 | |
| 	if( szmodword && al >= szmodword ) return 1;
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| 
 | |
| 	return ds->dsg_kind == DSG_FIXED &&
 | |
| 	       ((! szmodword && ds->dsg_offset % word_align == 0) ||
 | |
| 		(! wordmodsz && ds->dsg_offset % size == 0));
 | |
| }
 | |
| 
 | |
| CodeCopy(lhs, rhs, sz, psize)
 | |
| 	register struct desig *lhs, *rhs;
 | |
| 	arith sz, *psize;
 | |
| {
 | |
| 	struct desig l, r;
 | |
| 
 | |
| 	l = *lhs;
 | |
| 	r = *rhs;
 | |
| 	*psize -= sz;
 | |
| 	lhs->dsg_offset += sz;
 | |
| 	rhs->dsg_offset += sz;
 | |
| 	CodeAddress(&r);
 | |
| 	C_loi(sz);
 | |
| 	CodeAddress(&l);
 | |
| 	C_sti(sz);
 | |
| }
 | |
| 
 | |
| CodeMove(rhs, left, rtp)
 | |
| 	register struct desig *rhs;
 | |
| 	register struct node *left;
 | |
| 	struct type *rtp;
 | |
| {
 | |
| 	struct desig dsl;
 | |
| 	register struct desig *lhs = &dsl;
 | |
| 	register struct type *ltp = left->nd_type;
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| 
 | |
| 	dsl = InitDesig;
 | |
| 	/*	Generate code for an assignment. Testing of type
 | |
| 		compatibility and the like is already done.
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| 		Go through some (considerable) trouble to see if
 | |
| 		a BLM can be generated.
 | |
| 	*/
 | |
| 
 | |
| 	switch( rhs->dsg_kind )	{
 | |
| 	case DSG_LOADED:
 | |
| 		CodeDesig(left, lhs);
 | |
| 		if( rtp->tp_fund == T_STRINGCONST )	{
 | |
| 			CodeAddress(lhs);
 | |
| 			C_blm(lhs->dsg_packed ? ltp->tp_psize : ltp->tp_size);
 | |
| 			return;
 | |
| 		}
 | |
| 		CodeStore(lhs, ltp);
 | |
| 		return;
 | |
| 
 | |
| 	case DSG_PLOADED:
 | |
| 	case DSG_PFIXED:
 | |
| 		CodeAddress(rhs);
 | |
| 		CodeValue(rhs, rtp);
 | |
| 		CodeDStore(left);
 | |
| 		return;
 | |
| 
 | |
| 	case DSG_FIXED:	{
 | |
| 		arith tpsize;
 | |
| 
 | |
| 		CodeDesig(left, lhs);
 | |
| 		tpsize = lhs->dsg_packed ? ltp->tp_psize : ltp->tp_size;
 | |
| 		if( lhs->dsg_kind == DSG_FIXED &&
 | |
| 		    lhs->dsg_offset % word_size == rhs->dsg_offset % word_size
 | |
| 		  )	{
 | |
| 			arith size = tpsize;
 | |
| 
 | |
| 			if( size > 6 * word_size )	{
 | |
| 				/*	Do a block move
 | |
| 				*/
 | |
| 				struct desig l, r;
 | |
| 
 | |
| 				l = *lhs;
 | |
| 				r = *rhs;
 | |
| 				CodeAddress(&r);
 | |
| 				CodeAddress(&l);
 | |
| 				C_blm(size);
 | |
| 			}
 | |
| 			else	{
 | |
| 				register arith sz;
 | |
| 
 | |
| 				for( sz = 2 * word_size; sz; sz -= word_size) {
 | |
| 					while( size >= sz )
 | |
| 					/*	Then copy dwords, words.
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| 						Depend on peephole optimizer
 | |
| 					*/
 | |
| 					CodeCopy(lhs, rhs, sz, &size);
 | |
| 				}
 | |
| 			}
 | |
| 			return;
 | |
| 		}
 | |
| 		if( lhs->dsg_kind == DSG_PLOADED ||
 | |
| 		    lhs->dsg_kind == DSG_INDEXED )	{
 | |
| 			CodeAddress(lhs);
 | |
| 		}
 | |
| 	}
 | |
| 	default:
 | |
| 		crash("(CodeMove)");
 | |
| 		/*NOTREACHED*/
 | |
| 	}
 | |
| }
 | |
| 
 | |
| CodeValue(ds, tp)
 | |
| 	register struct desig *ds;
 | |
| 	register struct type *tp;
 | |
| {
 | |
| 	/*	Generate code to load the value of the designator described
 | |
| 		in "ds"
 | |
| 	*/
 | |
| 	arith size = ds->dsg_packed ? tp->tp_psize : tp->tp_size;
 | |
| 	int align = ds->dsg_packed ? tp->tp_palign : tp->tp_align;
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| 
 | |
| 	switch( ds->dsg_kind )	{
 | |
| 	case DSG_LOADED:
 | |
| 		break;
 | |
| 
 | |
| 	case DSG_FIXED:
 | |
| 		if( ds->dsg_offset % word_size == 0 && size == word_size ) {
 | |
| 			if( ds->dsg_name )
 | |
| 				C_loe_dnam(ds->dsg_name, ds->dsg_offset);
 | |
| 			else
 | |
| 				C_lol(ds->dsg_offset);
 | |
| 			break;
 | |
| 		}
 | |
| 		/* Fall through */
 | |
| 	case DSG_PLOADED:
 | |
| 	case DSG_PFIXED:
 | |
| 		if( properly(ds, size, align) )	{
 | |
| 			CodeAddress(ds);
 | |
| 			C_loi(size);
 | |
| 			break;
 | |
| 		}
 | |
| 		crash("(CodeValue)");
 | |
| 		break;
 | |
| 
 | |
| 	case DSG_INDEXED:
 | |
| 		C_lar(word_size);
 | |
| 		break;
 | |
| 
 | |
| 	default:
 | |
| 		crash("(CodeValue)");
 | |
| 		/*NOTREACHED*/
 | |
| 	}
 | |
| 
 | |
| 	ds->dsg_kind = DSG_LOADED;
 | |
| }
 | |
| 
 | |
| CodeStore(ds, tp)
 | |
| 	register struct desig *ds;
 | |
| 	register struct type *tp;
 | |
| {
 | |
| 	/*	Generate code to store the value on the stack in the designator
 | |
| 		described in "ds"
 | |
| 	*/
 | |
| 	struct desig save;
 | |
| 	arith size = ds->dsg_packed ? tp->tp_psize : tp->tp_size;
 | |
| 	int align = ds->dsg_packed ? tp->tp_palign : tp->tp_align;
 | |
| 
 | |
| 	save = *ds;
 | |
| 	
 | |
| 	switch( ds->dsg_kind )	{
 | |
| 	case DSG_FIXED:
 | |
| 		if( ds->dsg_offset % word_size == 0 && size == word_size ) {
 | |
| 			if( ds->dsg_name )
 | |
| 				C_ste_dnam(ds->dsg_name, ds->dsg_offset);
 | |
| 			else
 | |
| 				C_stl(ds->dsg_offset);
 | |
| 			break;
 | |
| 		}
 | |
| 		/* Fall through */
 | |
| 	case DSG_PLOADED:
 | |
| 	case DSG_PFIXED:
 | |
| 		CodeAddress(&save);
 | |
| 		if( properly(ds, size, align) )	{
 | |
| 			C_sti(size);
 | |
| 			break;
 | |
| 		}
 | |
| 		crash("(CodeStore)");
 | |
| 		break;
 | |
| 
 | |
| 	case DSG_INDEXED:
 | |
| 		C_sar(word_size);
 | |
| 		break;
 | |
| 
 | |
| 	default:
 | |
| 		crash("(CodeStore)");
 | |
| 		/*NOTREACHED*/
 | |
| 	}
 | |
| 
 | |
| 	ds->dsg_kind = DSG_INIT;
 | |
| }
 | |
| 
 | |
| CodeAddress(ds)
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| 	register struct desig *ds;
 | |
| {
 | |
| 	/*	Generate code to load the address of the designator described
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| 	   	in "ds"
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| 	*/
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| 
 | |
| 	switch( ds->dsg_kind )	{
 | |
| 	case DSG_PLOADED:
 | |
| 		if( ds->dsg_offset )
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| 			C_adp(ds->dsg_offset);
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| 		break;
 | |
| 
 | |
| 	case DSG_FIXED:
 | |
| 		if( ds->dsg_name )	{
 | |
| 			C_lae_dnam(ds->dsg_name, ds->dsg_offset);
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| 			break;
 | |
| 		}
 | |
| 		C_lal(ds->dsg_offset);
 | |
| 		if( ds->dsg_def )
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| 			ds->dsg_def->df_flags |= D_NOREG;
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| 		break;
 | |
| 		
 | |
| 	case DSG_PFIXED:
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| 		if( ds->dsg_name )
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| 			C_loe_dnam(ds->dsg_name, ds->dsg_offset);
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| 		else
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| 			C_lol(ds->dsg_offset);
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| 		break;
 | |
| 
 | |
| 	case DSG_INDEXED:
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| 		C_aar(word_size);
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| 		break;
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| 
 | |
| 	default:
 | |
| 		crash("(CodeAddress)");
 | |
| 		/*NOTREACHED*/
 | |
| 	}
 | |
| 
 | |
| 	ds->dsg_offset = 0;
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| 	ds->dsg_kind = DSG_PLOADED;
 | |
| }
 | |
| 
 | |
| CodeFieldDesig(df, ds)
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| 	register struct def *df;
 | |
| 	register struct desig *ds;
 | |
| {
 | |
| 	/* Generate code for a field designator. Only the code common for
 | |
| 	   address as well as value computation is generated, and the
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| 	   resulting information on where to find the designator is placed
 | |
| 	   in "ds". "df" indicates the definition of the field.
 | |
| 	*/
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| 
 | |
| 	if( ds->dsg_kind == DSG_INIT )	{
 | |
| 		/* In a WITH statement. We must find the designator in the
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| 		   WITH statement, and act as if the field is a selection
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| 		   of this designator.
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| 		   So, first find the right WITH statement, which is the
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| 		   first one of the proper record type, which is
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| 		   recognized by its scope indication.
 | |
| 		*/
 | |
| 		register struct withdesig *wds = WithDesigs;
 | |
| 
 | |
| 		assert(wds != 0);
 | |
| 
 | |
| 		while( wds->w_scope != df->df_scope )	{
 | |
| 			wds = wds->w_next;
 | |
| 			assert(wds != 0);
 | |
| 		}
 | |
| 
 | |
| 		/* Found it. Now, act like it was a selection.
 | |
| 		*/
 | |
| 		*ds = wds->w_desig;
 | |
| 		assert(ds->dsg_kind == DSG_PFIXED);
 | |
| 	}
 | |
| 
 | |
| 	switch( ds->dsg_kind )	{
 | |
| 		case DSG_PLOADED:
 | |
| 		case DSG_FIXED:
 | |
| 			ds->dsg_offset += df->fld_off;
 | |
| 			break;
 | |
| 
 | |
| 		case DSG_PFIXED:
 | |
| 		case DSG_INDEXED:
 | |
| 			CodeAddress(ds);
 | |
| 			ds->dsg_kind = DSG_PLOADED;
 | |
| 			ds->dsg_offset = df->fld_off;
 | |
| 			break;
 | |
| 
 | |
| 		default:
 | |
| 			crash("(CodeFieldDesig)");
 | |
| 	}
 | |
| 
 | |
| 	ds->dsg_packed = df->fld_flags & F_PACKED;
 | |
| }
 | |
| 
 | |
| CodeVarDesig(df, ds)
 | |
| 	register struct def *df;
 | |
| 	register struct desig *ds;
 | |
| {
 | |
| 	/*	Generate code for a variable represented by a "def" structure.
 | |
| 		Of course, there are numerous cases: the variable is local,
 | |
| 		it is a value parameter, it is a var parameter, it is one of
 | |
| 		those of an enclosing procedure, or it is global.
 | |
| 	*/
 | |
| 	register struct scope *sc = df->df_scope;
 | |
| 
 | |
| 	assert(ds->dsg_kind == DSG_INIT);
 | |
| 
 | |
| 	if( df->var_name )	{
 | |
| 		/* this variable has been given a name, so it is global.
 | |
| 		   It is directly accessible.
 | |
| 		*/
 | |
| 		ds->dsg_name = df->var_name;
 | |
| 		ds->dsg_offset = 0;
 | |
| 		ds->dsg_kind = DSG_FIXED;
 | |
| 		return;
 | |
| 	}
 | |
| 
 | |
| 	if( sc->sc_level != proclevel )	{
 | |
| 		/* the variable is local to a statically enclosing procedure.
 | |
| 		*/
 | |
| 		assert(proclevel > sc->sc_level);
 | |
| 
 | |
| 		df->df_flags |= D_NOREG;
 | |
| 		if( df->df_flags & (D_VARPAR|D_VALPAR) )	{
 | |
| 			/* value or var parameter
 | |
| 			*/
 | |
| 			C_lxa((arith) (proclevel - sc->sc_level));
 | |
| 			if( (df->df_flags & D_VARPAR) ||
 | |
| 			    IsConformantArray(df->df_type) )	{
 | |
| 				/* var parameter or conformant array.
 | |
| 				   For conformant array's, the address is
 | |
| 				   passed.
 | |
| 				*/
 | |
| 				C_adp(df->var_off);
 | |
| 				C_loi(pointer_size);
 | |
| 				ds->dsg_offset = 0;
 | |
| 				ds->dsg_kind = DSG_PLOADED;
 | |
| 				return;
 | |
| 			}
 | |
| 		}
 | |
| 		else
 | |
| 			C_lxl((arith) (proclevel - sc->sc_level));
 | |
| 
 | |
| 		ds->dsg_kind = DSG_PLOADED;
 | |
| 		ds->dsg_offset = df->var_off;
 | |
| 		return;
 | |
| 	}
 | |
| 
 | |
| 	/* Now, finally, we have a local variable or a local parameter
 | |
| 	*/
 | |
| 	if( (df->df_flags & D_VARPAR) || IsConformantArray(df->df_type) )
 | |
| 		/* a var parameter; address directly accessible. */
 | |
| 		ds->dsg_kind = DSG_PFIXED;
 | |
| 	else
 | |
| 		ds->dsg_kind = DSG_FIXED;
 | |
| 
 | |
| 	ds->dsg_offset = df->var_off;
 | |
| 	ds->dsg_def = df;
 | |
| }
 | |
| 
 | |
| CodeBoundDesig(df, ds)
 | |
| 	register struct def *df;
 | |
| 	register struct desig *ds;
 | |
| {
 | |
| 	/* Generate code for the lower- and upperbound of a conformant array */
 | |
| 
 | |
| 	assert(ds->dsg_kind == DSG_INIT);
 | |
| 
 | |
| 	if( df->df_scope->sc_level < proclevel )	{
 | |
| 		C_lxa((arith) (proclevel - df->df_scope->sc_level));
 | |
| 		if( df->df_kind == D_UBOUND )	{
 | |
| 			C_ldf(df->bnd_type->arr_cfdescr);
 | |
| 			C_adi(word_size);
 | |
| 		}
 | |
| 		else
 | |
| 			C_lof(df->bnd_type->arr_cfdescr);
 | |
| 	}
 | |
| 	else	{
 | |
| 		if( df->df_kind == D_UBOUND )	{
 | |
| 			C_ldl(df->bnd_type->arr_cfdescr);
 | |
| 			C_adi(word_size);
 | |
| 		}
 | |
| 		else
 | |
| 			C_lol(df->bnd_type->arr_cfdescr);
 | |
| 	}
 | |
| 
 | |
| 	ds->dsg_kind = DSG_LOADED;
 | |
| }
 | |
| 
 | |
| CodeFuncDesig(df, ds)
 | |
| 	register struct def *df;
 | |
| 	register struct desig *ds;
 | |
| {
 | |
| 	/* generate code to store the function result */
 | |
| 
 | |
| 	if( df->df_scope->sc_level + 1 < proclevel )	{
 | |
| 		/* Assignment to function-identifier in the declaration-part of
 | |
| 		   the function (i.e. in the statement-part of a nested function
 | |
| 		   or procedure).
 | |
| 		*/
 | |
| 		if( !options['R'] ) {
 | |
| 			C_loc((arith)1);
 | |
| 			C_lxl((arith) (proclevel - df->df_scope->sc_level - 1));
 | |
| 			C_adp(df->prc_bool);
 | |
| 			C_sti(int_size);
 | |
| 		}
 | |
| 
 | |
| 		C_lxl((arith) (proclevel - df->df_scope->sc_level - 1));
 | |
| 		ds->dsg_kind = DSG_PLOADED;
 | |
| 	}
 | |
| 	else	{
 | |
| 		/* Assignment to function-identifier in the statement-part of
 | |
| 		   the function.
 | |
| 		*/
 | |
| 		if( !options['R'] ) {
 | |
| 			C_loc((arith)1);
 | |
| 			C_stl(df->prc_bool);
 | |
| 		}
 | |
| 
 | |
| 		ds->dsg_kind = DSG_FIXED;
 | |
| 	}
 | |
| 	assert(df->prc_res < 0);
 | |
| 	ds->dsg_offset = df->prc_res;
 | |
| }
 | |
| 
 | |
| CodeDesig(nd, ds)
 | |
| 	register struct node *nd;
 | |
| 	register struct desig *ds;
 | |
| {
 | |
| 	/*	Generate code for a designator. Use divide and conquer
 | |
| 		principle
 | |
| 	*/
 | |
| 	register struct def *df;
 | |
| 
 | |
| 	switch( nd->nd_class )	{	/* Divide */
 | |
| 	case Def:
 | |
| 		df = nd->nd_def;
 | |
| 
 | |
| 		switch( df->df_kind )	{
 | |
| 		case D_FIELD:
 | |
| 			CodeFieldDesig(df, ds);
 | |
| 			break;
 | |
| 
 | |
| 		case D_VARIABLE:
 | |
| 			CodeVarDesig(df, ds);
 | |
| 			break;
 | |
| 
 | |
| 		case D_LBOUND:
 | |
| 		case D_UBOUND:
 | |
| 			CodeBoundDesig(df, ds);
 | |
| 			break;
 | |
| 
 | |
| 		case D_FUNCTION:
 | |
| 			CodeFuncDesig(df, ds);
 | |
| 			break;
 | |
| 
 | |
| 		default:
 | |
| 			crash("(CodeDesig) Def");
 | |
| 		}
 | |
| 		break;
 | |
| 
 | |
| 	case LinkDef:
 | |
| 		assert(nd->nd_symb == '.');
 | |
| 
 | |
| 		CodeDesig(nd->nd_left, ds);
 | |
| 		CodeFieldDesig(nd->nd_def, ds);
 | |
| 		break;
 | |
| 
 | |
| 	case Arrsel:	{
 | |
| 		struct type *tp;
 | |
| 
 | |
| 		assert(nd->nd_symb == '[');
 | |
| 
 | |
| 		CodeDesig(nd->nd_left, ds);
 | |
| 		CodeAddress(ds);
 | |
| 		CodePExpr(nd->nd_right);
 | |
| 
 | |
| 		/* Now load address of descriptor
 | |
| 		*/
 | |
| 		tp = nd->nd_left->nd_type;
 | |
| 		if( IsConformantArray(tp) )	{
 | |
| 			if( tp->arr_sclevel < proclevel )	{
 | |
| 				C_lxa((arith) (proclevel - tp->arr_sclevel));
 | |
| 				C_adp(tp->arr_cfdescr);
 | |
| 			}
 | |
| 			else
 | |
| 				C_lal(tp->arr_cfdescr);
 | |
| 		}
 | |
| 		else
 | |
| 			C_lae_dlb(tp->arr_ardescr, (arith) 0);
 | |
| 
 | |
| 		if( options['A'] ) {
 | |
| 			C_cal("_rcka");
 | |
| 		}
 | |
| 		ds->dsg_kind = DSG_INDEXED;
 | |
| 		ds->dsg_packed = IsPacked(tp);
 | |
| 		break;
 | |
| 	}
 | |
| 
 | |
| 	case Arrow:
 | |
| 		assert(nd->nd_symb == '^');
 | |
| 
 | |
| 		if( nd->nd_right->nd_type->tp_fund == T_FILE )	{
 | |
| 			CodeDAddress(nd->nd_right);
 | |
| 			C_cal("_wdw");
 | |
| 			C_asp(pointer_size);
 | |
| 			C_lfr(pointer_size);
 | |
| 			ds->dsg_kind = DSG_PLOADED;
 | |
| 			ds->dsg_packed = 1;
 | |
| 			break;
 | |
| 		}
 | |
| 
 | |
| 		CodeDesig(nd->nd_right, ds);
 | |
| 		switch(ds->dsg_kind) {
 | |
| 		case DSG_LOADED:
 | |
| 			ds->dsg_kind = DSG_PLOADED;
 | |
| 			break;
 | |
| 
 | |
| 		case DSG_INDEXED:
 | |
| 		case DSG_PLOADED:
 | |
| 		case DSG_PFIXED:
 | |
| 			CodeValue(ds, nd->nd_right->nd_type);
 | |
| 			ds->dsg_kind = DSG_PLOADED;
 | |
| 			ds->dsg_offset = 0;
 | |
| 			break;
 | |
| 
 | |
| 		case DSG_FIXED:
 | |
| 			ds->dsg_kind = DSG_PFIXED;
 | |
| 			break;
 | |
| 
 | |
| 		default:
 | |
| 			crash("(CodeDesig) Uoper");
 | |
| 		}
 | |
| 		break;
 | |
| 		
 | |
| 	default:
 | |
| 		crash("(CodeDesig) class");
 | |
| 	}
 | |
| }
 |