type.h

/****h* libfirm/type
 *
 * NAME
 *   file type.h - datastructure to hold type information.
 * COPYRIGHT
 *  (C) 2001 by Universitaet Karlsruhe
 * AUTHORS
 *  Goetz Lindenmaier
 *
 * NOTES
 *  This module supplies a datastructure to represent all types
 *  known in the compiled program.  This includes types specified
 *  in the program as well as types defined by the language.  In the
 *  view of the intermediate representation there is no difference
 *  between these types.
 *
 *  There exist several kinds of types, arranged by the structure of
 *  the type.  A type is described by a set of attributes.  Some of
 *  these attributes are common to all types, others depend on the
 *  kind of the type.
 *
 *  Types are different from the modes defined in irmode:  Types are
 *  on the level of the programming language, modes at the level of
 *  the target processor.
 *
 * SEE ALSO
 *   tpop.h
 *****
 */
# ifndef _TYPE_H_
# define _TYPE_H_

# include "tpop.h"
# include "common.h"
# include "ident.h"
# include "irmode.h"
# include "bool.h"

#ifndef _ENTITY_TYPEDEF_
#define _ENTITY_TYPEDEF_
/* to resolve recursion between entity.h and type.h */
typedef struct entity entity;
#endif

#ifndef _IR_NODE_TYPEDEF_
#define _IR_NODE_TYPEDEF_
typedef struct ir_node ir_node;
#endif

/****s* type/type
 *
 * NAME
 *   type - An abstract data type to represent types.
 * NOTE
 *  This is the abstract data type with which any type known in the
 *  compiled program can be represented.  This includes types specified
 *  in the program as well as types defined by the language.  In the
 *  view of the intermediate representation there is no difference
 *  between these types.
 *
 *  There exist several kinds of types, arranged by the structure of
 *  the type.  These are distinguished by a type opcode.
 *  A type is described by a set of attributes.  Some of these attributes
 *  are common to all types, others depend on the kind of the type.
 *
 *  The following describes the common attributes.  They can only be
 *  accessed by the functions given below.
 *
 * ATTRIBUTES
 *  The common fields are:
 *
 *  firm_kind    A firm_kind tag containing k_type.  This is useful
 *               for dynamically checking whether a node is a type node.
 *  type_op      A tp_op specifying the kind of the type.
 *  mode         The mode to be used to represent the type on a machine.
 *               @@@ maybe not global field??
 *  name         An identifier specifying the name of the type.  To be
 *               set by the frontend.
 *  size         The size of the type, i.e. an entity of this type will
 *               occupy size bytes in memory.  In several cases this is
 *               determined when fixing the layout of this type (class,
 *               struct, union, array, enumeration).
 *  state        The state of the type.  The state represents whether the
 *               layout of the type is undefined or fixed (values: layout_undefined
 *               or layout_fixed).  Compound types can have an undefined
 *               layout.  The layout of the basic types primitive and pointer
 *               is always layout_fixed.  If the layout of
 *               compound types is fixed all entities must have an offset
 *               and the size of the type must be set.
 *               A fixed layout for enumeration types means that each enumeration
 *               is associated with an implementation value.
 *  visit        A counter for walks of the type information.
 *
 *  These fields can only be accessed via access functions.
 *
 *  Depending on the value of type_op, i.e., depending on the kind of the
 *  type the adt contains further attributes.  These are documented below.
 * SEE ALSO
 *   class, struct, method, union, array, enumeration, pointer, primitive
 * SOURCE
 */
typedef struct type type;

void*       get_type_link(type *tp);
void        set_type_link(type *tp, void *l);
tp_op*      get_type_tpop(type *tp);
ident*      get_type_tpop_nameid(type *tp);
const char* get_type_tpop_name(type *tp);
tp_opcode   get_type_tpop_code(type *tp);

ir_mode*    get_type_mode(type *tp);
void        set_type_mode(type *tp, ir_mode* m);

ident*      get_type_ident(type *tp);
void        set_type_ident(type *tp, ident* id);
const char* get_type_name(type *tp);

int         get_type_size(type *tp);
/* For primitives and pointer types the size is always fixed.
   This call is legal but has no effect. */
void        set_type_size(type *tp, int size);

typedef enum {
  layout_undefined,    /* The layout of this type is not defined.
			  Address computation to access fields is not
			  possible, fields must be accessed by Sel nodes.
			  This is the default value except for pointer and
			  primitive types. */
  layout_fixed         /* The layout is fixed, all component/member entities
			  have an offset assigned.  Size of the type is known.
			  Arrays can be accessed by explicit address
			  computation. Default for pointer and primitive types.
		       */
} type_state;

type_state  get_type_state(type *tp);
/* For primitives and pointer types the layout is always fixed.
   This call is legal but has no effect. */
void        set_type_state(type *tp, type_state state);

unsigned long get_type_visited(type *tp);
void        set_type_visited(type *tp, unsigned long num);
/* Sets visited field in type to type_visited. */
void        mark_type_visited(type *tp);
/*****/

/****v* type/visited
 *
 * NAME
 *   type_visited -  visited flag to traverse the type information
 * PURPOSE
 *   Increase this flag by one before traversing the type information.
 *   Mark type nodes as visited by set_type_visited(type, type_visited).
 *   Check whether node was already visited by comparing get_type_visited(type)
 *   and type_visited.
 *   Or use the function to walk all types.
 * SEE ALSO
 *   typewalk
 * SOURCE
 */
extern unsigned long type_visited;
/*****/

/****f* type/is_type
 *
 * NAME
 *   is_type - Checks whether a pointer points to a type.
 * SYNOPSIS
 *   bool is_type            (void *thing);
 * INPUTS
 *   thing - a pointer
 * RESULT
 *   true if the thing is a type, else false
 ***
 */
int is_type            (void *thing);

/****** type/class
 * NAME
 *  Representation of a class type.
 * NOTE
 *  If the type opcode is set to type_class the type represents class
 *  types.  A list of fields and methods is associated with a class.
 *  Further a class can inherit from and bequest to other classes.
 *  @@@ value class???
 * ATTRIBUTES
 *  The following attributes are private to this type kind.
 *  member     All entities belonging to this class.  This are methode entities
 *             which have type_method or fields that can have any of the
 *             following type kinds: type_class, type_struct, type_union,
 *             type_array, type_enumeration, type_pointer, type_primitive.
 *
 *  subtypes   A list of direct subclasses.
 *
 *  supertypes A list of direct superclasses.
 *
 *  These are dynamic lists that can be grown with an "add_" function,
 *  but not shrinked.
 * SOURCE
 */
/* create a new class type */
type   *new_type_class (ident *name);

/** manipulate private fields of class type  **/
/* Adds the entity as member of the class.  */
void    add_class_member   (type *clss, entity *member);
/* Returns the number of members of this class. */
int     get_class_n_member (type *clss);
/* Returns the member at position pos, 0 <= pos < n_member */
entity *get_class_member   (type *clss, int pos);
/* Overwrites the member at position pos, 0 <= pos < n_member with
   the passed entity. */
void    set_class_member   (type *clss, entity *member, int pos);
/* Finds member in the list of members and overwrites it with NULL
 @@@ Doesn't work properly. */
void    remove_class_member(type *clss, entity *member);


/* Adds subtype as subtype to clss.
   Checks whether clss is a supertype of subtype.  If not
   adds also clss as supertype to subtype.  */
void    add_class_subtype   (type *clss, type *subtype);
/* Returns the number of subtypes */
int     get_class_n_subtype (type *clss);
/* Gets the subtype at position pos, 0 <= pos < n_subtype. */
type   *get_class_subtype   (type *clss, int pos);
/* Sets the subtype at positioin pos, 0 <= pos < n_subtype.  Does not
   set the corresponding supertype relation for subtype: this might
   be a different position! */
void    set_class_subtype   (type *clss, type *subtype, int pos);
/* Finds subtype in the list of subtypes and overwrites it with NULL
 @@@ Doesn't work properly. */
void    remove_class_subtype(type *clss, type *subtype);


/* Adds supertype as supertype to class.
   Checks whether clss is a subtype of supertype.  If not
   adds also clss as subtype to supertype.  */
void    add_class_supertype   (type *clss, type *supertype);
/* Returns the number of supertypes */
int     get_class_n_supertype (type *clss);
/* Gets the supertype at position pos,  0 <= pos < n_supertype. */
type   *get_class_supertype   (type *clss, int pos);
/* Sets the supertype at postition pos, 0 <= pos < n_subtype.  Does not
   set the corresponding subtype relation for supertype: this might
   be a different position! */
void    set_class_supertype   (type *clss, type *supertype, int pos);
/* Finds supertype in the list of supertypes and overwrites it with NULL
 @@@ Doesn't work properly. */
void    remove_class_supertype(type *clss, type *supertype);

/* typecheck */
bool    is_class_type(type *clss);
/*****/

/****** type/struct
 * NAME
 *  Representation of a struct type.
 * NOTE
 *  Type_strct represents aggregate types that consist of a list
 *  of fields.
 * ATTRIBUTES
 *  member   All entities belonging to this class.  This are the fields
 *           that can have any of the following types:  type_class,
 *           type_struct, type_union, type_array, type_enumeration,
 *  	     type_pointer, type_primitive.
 *           This is a dynamic list that can be grown with an "add_" function,
 *           but not shrinked.
 *           This is a dynamic list that can be grown with an "add_" function,
 *           but not shrinked.
 * SOURCE
 */
/* create a new type struct */
type   *new_type_struct (ident *name);

/* manipulate private fields of struct */
void    add_struct_member   (type *strct, entity *member);
int     get_struct_n_member (type *strct);
entity *get_struct_member   (type *strct, int pos);
void    set_struct_member   (type *strct, int pos, entity *member);
/* Finds member in the list of memberss and overwrites it with NULL
 @@@ Doesn't work properly. */
void    remove_struct_member (type *strct, entity *member);

/* typecheck */
bool    is_struct_type(type *strct);
/*****/

/****** type/method
 * NAME
 *  Representation of a method type.
 * NOTE
 *  A method type represents a method, function or procedure type.
 *  It contains a list of the parameter and result types, as these
 *  are part of the type description.  These lists should not
 *  be changed by a optimization, as a change creates a new method
 *  type.  Therefore optimizations should allocated new method types.
 *  The set_ routines are only for construction by a frontend.
 * ATTRIBUTES
 *  n_params    Number of parameters to the procedure.
 *              A procedure in FIRM has only call by value parameters.
 *
 *  param_type  A list with the types of parameters.  This list is ordered.
 *              The nth type in this list corresponds to the nth element
 *              in the parameter tuple that is a result of the start node.
 *  	        (See ircons.h for more information.)
 *
 *  n_res       The number of results of the method.  In general, procedures
 *              have zero results, functions one.
 *
 *  res_type    A list with the types of parameters.  This list is ordered.
 *              The nth type in this list corresponds to the nth input to
 *  	        Return nodes.  (See ircons.h for more information.)
 * SOURCE
 */

/* Create a new method type.
   N_param is the number of parameters, n_res the number of results.
   The arrays for the parameter and result types are not initialized by
   the constructor. */
type *new_type_method (ident *name, int n_param, int n_res);

/* manipulate private fields of method. */
int   get_method_n_params  (type *method);
type *get_method_param_type(type *method, int pos);
void  set_method_param_type(type *method, int pos, type* type);

int   get_method_n_res   (type *method);
type *get_method_res_type(type *method, int pos);
void  set_method_res_type(type *method, int pos, type* type);

/* typecheck */
bool  is_method_type     (type *method);
/*****/

/****** type/union
 * NAME
 *   Representation of a union type.
 * NOTE
 *   The union type represents union types.
 * ATTRIBUTES
 *   n_types        Number of unioned types.
 *   members        Entities for unioned types.  Fixed length array.
 *                  This is a dynamic list that can be grown with an "add_" function,
 *                  but not shrinked.
 * SOURCE
 */
/* create a new type union  */
type   *new_type_union (ident *name);

/* manipulate private fields of struct */
int     get_union_n_members      (type *uni);
void    add_union_member (type *uni, entity *member);
entity *get_union_member (type *uni, int pos);
void    set_union_member (type *uni, int pos, entity *member);
/* Finds member in the list of members and overwrites it with NULL
   @@@ Doesn't work properly. */
void    remove_union_member (type *uni, entity *member);

/* typecheck */
bool    is_union_type          (type *uni);
/*****/

#if 0
/* We don't need these if the union has entities, which it now
   does. The entities are necessary for the analysis algorithms. */
type  *get_union_unioned_type (type *uni, int pos);
void   set_union_unioned_type (type *uni, int pos, type *type);

ident *get_union_delim_nameid (type *uni, int pos);
const char *get_union_delim_name (type *uni, int pos);
void   set_union_delim_nameid (type *uni, int pos, ident *id);
#endif

/****** type/array
 * NAME
 *   Representation of an array type.
 * NOTE
 *   The array type represents rectangular multi dimensional arrays.
 * ATTRIBUTES
 *   n_dimensions     Number of array dimensions.
 *   *lower_bound     Lower bounds of dimensions.  Usually all 0.
 *   *upper_bound     Upper bounds or dimensions.
 *   *element_type    The type of the array elements.
 *   *element_ent     An entity for the array elements to be used for
 *                    element selection with Sel.
 *                    @@@ Do we need several entities?  One might want
 *                    to select a dimension and not a single element in
 *                    case of multidim arrays.
 * SOURCE
 */
/* create a new type array --
   Set dimension sizes after call to constructor with set_* routines.
   Entity for array elements is built automatically. */
type *new_type_array         (ident *name, int n_dimensions,
			      type *element_type);

/* manipulate private fields of array type */
int   get_array_n_dimensions (type *array);
void  set_array_bounds       (type *array, int dimension, ir_node *lower_bound,
                                                          ir_node *upper_bound);
void  set_array_lower_bound  (type *array, int dimension, ir_node *lower_bound);
void  set_array_upper_bound  (type *array, int dimension, ir_node *upper_bound);
ir_node * get_array_lower_bound  (type *array, int dimension);
ir_node * get_array_upper_bound  (type *array, int dimension);

void  set_array_element_type (type *array, type *type);
type *get_array_element_type (type *array);

void  set_array_element_entity (type *array, entity *ent);
entity *get_array_element_entity (type *array);

/* typecheck */
bool   is_array_type         (type *array);
/*****/

/****** type/enumeration
 * NAME
 *  Representation of an enumeration type.
 * NOTE
 *  Enumeration types need not necessarily be represented explicitly
 *  by Firm types, as the frontend can lower them to integer constants as
 *  well.  For debugging purposes or similar tasks this information is useful.
 * ATTRIBUTES
 *   *enum           The target values representing the constants used to
 *                   represent individual enumerations.
 *   *enum_nameid    Idents containing the source program name of the enumeration
 *  		     constants
 *
*****
*/
/* create a new type enumeration -- set the enumerators independently */
type   *new_type_enumeration    (ident *name, int n_enums);

/* manipulate fields of enumeration type. */
int     get_enumeration_n_enums (type *enumeration);

void    set_enumeration_enum    (type *enumeration, int pos, tarval *con);
tarval *get_enumeration_enum    (type *enumeration, int pos);

void    set_enumeration_nameid  (type *enumeration, int pos, ident *id);
ident  *get_enumeration_nameid  (type *enumeration, int pos);
const char *get_enumeration_name(type *enumeration, int pos);

/* typecheck */
bool    is_enumeration_type     (type *enumeration);
/*****/

/****** type/pointer
 * NAME
 *   Representation of a pointer type.
 * NOTE
 *   Pointer types.
 * ATTRIBUTES
 *   points_to       The type of the entity this pointer points to.
 * SOURCE
 */
/* Create a new type pointer */
type *new_type_pointer           (ident *name, type *points_to);

/* manipulate fields of type_pointer */
void  set_pointer_points_to_type (type *pointer, type *type);
type *get_pointer_points_to_type (type *pointer);

/* typecheck */
bool  is_pointer_type            (type *pointer);
/*****/

/****** type/primitive
 * NAME
 *   Representation of a primitive type.
 * NOTE
 *   Primitive types are types that represent indivisible data values that
 *   map directly to modes.  They don't have a private attribute.  The
 *   important information they carry is held in the common mode field.
 * SOURCE
*/
/* create a new type primitive */
type *new_type_primitive (ident *name, ir_mode *mode);

/* typecheck */
bool  is_primitive_type  (type *primitive);
/*****/

# endif /* _TYPE_H_ */