// Copyright (C) 1984-1995 by Symantec
// Copyright (C) 2000-2009 by Digital Mars
// All Rights Reserved
// http://www.digitalmars.com
// Written by Walter Bright
/*
 * This source file is made available for personal use
 * only. The license is in /dmd/src/dmd/backendlicense.txt
 * For any other uses, please contact Digital Mars.
 */

//#pragma once
#ifndef DT_H
#define DT_H	1

/**********************************
 * Data definitions
 *	DTibytes	1..7 bytes
 *	DT1byte		one byte of data follows
 *			n
 *	DTabytes	offset of bytes of data
 *			a { a data bytes }
 *	DTnbytes	bytes of data
 *			a { a data bytes }
 *			a = offset
 *	DTazeros	# of 0 bytes
 *			a
 *	DTsymsize	same as DTazeros, but the type of the symbol gives
 *			the size
 *	DTcommon	# of 0 bytes (in a common block)
 *			a
 *	DTxoff		offset from symbol
 *			w a
 *			w = symbol number (pointer for CPP)
 *			a = offset
 *	DTcoff		offset into code segment
 *	DTend		mark end of list
 */

struct dt_t
{   dt_t *DTnext;			// next in list
    char dt;				// type (DTxxxx)
    unsigned char Dty;			// pointer type
    union
    {
	struct				// DTibytes
	{   char DTn_;			// number of bytes
	    #define DTn _DU._DI.DTn_
	    char DTdata_[7];		// data
	    #define DTdata _DU._DI.DTdata_
	}_DI;
	char DTonebyte_;		// DT1byte
	#define DTonebyte _DU.DTonebyte_
	targ_size_t DTazeros_;		// DTazeros,DTcommon,DTsymsize
	#define DTazeros _DU.DTazeros_
	struct				// DTabytes
	{
	    char *DTpbytes_;		// pointer to the bytes
	    #define DTpbytes _DU._DN.DTpbytes_
	    unsigned DTnbytes_;		// # of bytes
	    #define DTnbytes _DU._DN.DTnbytes_
#if TX86
	    int DTseg_;			// segment it went into
	    #define DTseg _DU._DN.DTseg_
#endif
	    targ_size_t DTabytes_;		// offset of abytes for DTabytes
	    #define DTabytes _DU._DN.DTabytes_
	}_DN;
	struct				// DTxoff
	{
	    symbol *DTsym_;		// symbol pointer
	    #define DTsym _DU._DS.DTsym_
	    targ_size_t DToffset_;	// offset from symbol
	    #define DToffset _DU._DS.DToffset_
	}_DS;
    }_DU;
};

enum
{
    DT_abytes,
    DT_azeros,  // 1
    DT_xoff,
    DT_1byte,
    DT_nbytes,
    DT_common,
    DT_symsize,
    DT_coff,
    DT_ibytes, // 8
};

#if TX86
dt_t *dt_calloc(char dtx);
void dt_free(dt_t *);
void dt_term(void);
#elif TARGET_MAC
dt_t *dt_calloc(void);
void dt_free(dt_t *);
#endif

dt_t **dtnbytes(dt_t **,targ_size_t,const char *);
dt_t **dtabytes(dt_t **pdtend,tym_t ty, targ_size_t offset, targ_size_t size, const char *ptr);
dt_t **dtdword(dt_t **,long value);
dt_t **dtnzeros(dt_t **pdtend,targ_size_t size);
dt_t **dtxoff(dt_t **pdtend,symbol *s,targ_size_t offset,tym_t ty);
dt_t **dtselfoff(dt_t **pdtend,targ_size_t offset,tym_t ty);
dt_t **dtcoff(dt_t **pdtend,targ_size_t offset);
dt_t ** dtcat(dt_t **pdtend,dt_t *dt);
void dt_optimize(dt_t *dt);
void dtsymsize(symbol *);
void init_common(symbol *);
unsigned dt_size(dt_t *dtstart);

#endif /* DT_H */

