1 /* Copyright (C) 1998 - 2000 by Universitaet Karlsruhe
2 ** All rights reserved.
4 ** Authors: Martin Trapp, Christian Schaefer,
7 ** ircons.h ir node construction
13 *** Ideas for imrovement:
15 Handle construction of exceptions more comfortable:
16 Add new constructors that pass the exception region (or better the
17 Phi for the memories, the ex. region can be found from there) as parameter,
18 constructor then adds all Proj nodes and returns the pointer
19 to the Proj node that selects the result of the arithmetic operation.
21 Maybe hide the exception region in a global variable, especially if
22 it is always unambiguous.
25 /****h* libfirm/ircons
31 * This file documents all datatypes and constructors needed to
32 * build a FIRM representation of a pocedure. The constructors are
33 * also implemented in this file.
35 * The documentation also gives a short manual how to use the library.
37 * For extensive documentation of FIRM see UKA Techreport 1999-14.
45 * This struct contains all information about a procedure.
46 * It's allocated directly to memory.
48 * The fields of ir_graph:
50 * *ent The entity describing this procedure.
52 * The beginning and end of a graph:
54 * *start_block This ir_node is the block that contains the unique
55 * start node of the procedure. With it it contains
56 * the Proj's on starts results.
57 * Further all Const nodes are placed in the start block.
58 * *start This ir_node is the unique start node of the procedure.
60 * *end_block This ir_node is the block that contains the unique
61 * end node of the procedure. This block contains no
63 * *end This ir_node is the unique end node of the procedure.
65 * The following nodes are Projs from the start node, held in ir_graph for
68 * *frame The ir_node producing the pointer to the stack frame of
69 * the procedure as output. This is the Proj node on the
70 * third output of the start node. This output of the start
71 * node is tagged as pns_frame_base. In FIRM most lokal
72 * variables are modeled as data flow edges. Static
73 * allocated arrays can not be represented as dataflow
74 * edges. Therefore FIRM has to represent them in the stack
77 * *globals This models a pointer to a space in the memory where
78 * _all_ global things are held. Select from this pointer
79 * with a Sel node the pointer to a global variable /
80 * procedure / compiler known function... .
82 * *args The ir_node that produces the arguments of the method as
83 * it's result. This is a Proj node on the fourth output of
84 * the start node. This output is tagged as pns_args.
86 * *bad The bad node is an auxiliary node. It is needed only once,
87 * so there is this globally reachable node.
89 * Datastructures that are private to a graph:
91 * *obst An obstack that contains all nodes.
93 * *current_block A pointer to the current block. Any node created with
94 * one of the node constructors (new_<opcode>) are assigned
95 * to this block. It can be set with switch_block(block).
96 * Only needed for ir construction.
98 * params/n_loc An int giving the number of local variables in this
99 * procedure. This is neede for ir construction. Name will
102 * *value_table This hash table (pset) is used for global value numbering
103 * for optimizing use in iropt.c.
105 * *Phi_in_stack; a stack needed for automatic Phi construction, needed only
106 * during ir construction.
108 * visited A int used as flag to traverse the ir_graph.
110 * block_visited A int used as a flag to traverse block nodes in the graph.
112 * Three kinds of nodes
113 * --------------------
115 * There are three kinds of nodes known to the ir: entities,
116 * types, and ir_nodes
118 * + ir_nodes are the actual nodes of the FIRM intermediate representation.
119 * They represent operations on the data of the program and control flow
122 * + entity ==> implemented in entity.h
123 * Refers to a single entity of the compiled program, e.g. a field of a
124 * class or a method. If a method or variable can not be assigned to
125 * a method or class or the like, it is a global object.
127 * + types ==> implemented in type.h
128 * With types type information is represented. There are several type
131 * Implementation of the FIRM operations: ir_node
132 * ----------------------------------------------
134 * Ir_nodes represent operations on the data of the program and control flow
135 * operations. Examples of ir_nodes: Add, Jmp, Cmp
137 * FIRM is a dataflow graph. A dataflow graph is a directed graph,
138 * so that every node has incoming and outgoing edges. A node is
139 * executable if every input at it's incoming edges is available.
140 * Execution of the dataflow graph is started at the Start node which
141 * has no incoming edges and ends when the End node executes, even if
142 * there are still executable or not executed nodes. (Is this true,
143 * or must all executable nodes be executed?) (There are exceptions
144 * to the dataflow paradigma that all inputs have to be available
145 * before a node can execute: Phi, Block. See UKA Techreport
148 * The implementation of FIRM differs from the view as a dataflow
149 * graph. To allow fast traversion of the graph edges are
150 * implemented as C-pointers. Inputs to nodes are not ambiguous, the
151 * results can be used by several other nodes. Each input can be
152 * implemented as a single pointer to a predecessor node, outputs
153 * need to be lists of pointers to successors. Therefore a node
154 * contains pointers to it's predecessor so that the implementation is a
155 * dataflow graph with reversed edges. It has to be traversed bottom
158 * All nodes of the ir have the same basic structure. They are
159 * distinguished by a field containing the opcode.
161 * The fields of an ir_node:
163 * kind A firm_kind tag containing k_ir_node. This is useful for
164 * dynamically checking the type of a node.
166 * *op This ir_op gives the opcode as a tag and a string
167 * and the number of attributes of an ir_node. There is
168 * one statically allocated struct ir_op for each opcode.
170 * *mode The ir_mode of the operation represented by this firm
171 * node. The mode of the operation is the mode of it's
172 * result. A Firm mode is a datatype as known to the target,
173 * not a type of the source language.
175 * visit A flag for traversing the ir.
177 * **in An array with pointers to the node's predecessors.
179 * *link A pointer to an ir_node. With this pointer all Phi nodes
180 * are attached to a Block, i.e., a Block points to it's
181 * first Phi node, this node points to the second Phi node
182 * in the Block and so fourth. Used in mature_block
183 * to find all Phi nodes to be matured. It's also used to
184 * annotate a node with a better, optimized version of it.
186 * attr An attr struct containing the attributes of the nodes. The
187 * attributes depend on the opcode of the node. The number
188 * of these attributes is given in op.
192 * Not yet documented. See irop.h.
196 * Not yet documented. See irmode.h.
198 * GLOBAL VARIABLES -- now also fields of ir_graph.
201 * current_ir_graph Points to the current ir_graph. All constructors for
202 * nodes add nodes to this graph.
204 * ir_visited An int used as flag to traverse the ir_graph.
206 * block_visited An int used as a flag to traverse block nodes in the
209 * Others not yet documented.
213 * CONSTRUCTOR FOR IR_GRAPH --> see irgraph.h
214 * ========================
217 * PROCEDURE TO CONSTRUCT AN IR GRAPH --> see also Firm tutorial
218 * ==================================
220 * This library supplies several interfaces to construct a FIRM graph for
222 * * A "comfortable" interface generating SSA automatically. Automatically
223 * computed predecessors of nodes need not be specified in the constructors.
224 * (new_<Node> constructurs and a set of additional routines.)
225 * * A less comfortable interface where all predecessors except the block
226 * an operation belongs to need to be specified. SSA must be constructed
227 * by hand. (new_<Node> constructors and switch_block()). This interface
228 * is called "block oriented". It automatically calles the local optimizations
230 * * An even less comfortable interface where the block needs to be specified
231 * explicitly. This is called the "raw" interface. (new_r_<Node>
232 * constructors). These nodes are not optimized.
234 * To use the functionality of the comfortable interface correctly the Front
235 * End needs to follow certain protocols. This is explained in the following.
236 * To build a correct IR with the other interfaces study the semantics of
237 * the firm node (See tech-reprot UKA 1999-14). For the construction of
238 * types and entities see the documentation in those modules.
240 * First the Frontend needs to decide which variables and values used in
241 * a procedure can be represented by dataflow edges. These are variables
242 * that need not be saved to memory as they cause no side effects visible
243 * out of the procedure. Often these are all compiler generated
244 * variables and simple local variables of the procedure as integers,
245 * reals and pointers. The frontend has to count and number these variables.
247 * First an ir_graph needs to be constructed with new_ir_graph. The
248 * constructor gets the number of local variables. The graph is hold in the
249 * global variable irg.
251 * Now the construction of the procedure can start. Several basic blocks can
252 * be constructed in parallel, but the code within each block needs to
253 * be constructed (almost) in program order.
255 * A global variable holds the current basic block. All (non block) nodes
256 * generated are added to this block. The current block can be set with
257 * switch_block(block). If several blocks are constructed in parallel block
258 * switches need to be performed constantly.
260 * To generate a Block node (with the comfortable interface) it's predecessor
261 * control flow nodes need not be known. In case of cyclic control flow these
262 * can not be known when the block is constructed. With add_in_edge(block,
263 * cfnode) predecessors can be added to the block. If all predecessors are
264 * added to the block mature_block(b) needs to be called. Calling mature_block
265 * early improves the efficiency of the Phi node construction algorithm.
266 * But if several blocks are constructed at once, mature_block must only
267 * be called after performing all set_values and set_stores in the block!
268 * (See documentation of new_immBlock constructor.)
270 * The constructors of arithmetic nodes require that their predecessors
271 * are mentioned. Sometimes these are available in the Frontend as the
272 * predecessors have just been generated by the frontend. If they are local
273 * values the predecessors can be obtained from the library with a call to
274 * get_value(local_val_nr). (local_val_nr needs to be administered by
275 * the Frontend.) A call to get_value triggers the generation of Phi nodes.
276 * If an arithmetic operation produces a local value this value needs to be
277 * passed to the library by set_value(node, local_val_nr).
278 * In straight line code these two operations just remember and return the
279 * pointer to nodes producing the value. If the value passes block boundaries
280 * Phi nodes can be inserted.
281 * Similar routines exist to manage the Memory operands: set_store and
284 * Several nodes produce more than one result. An example is the Div node.
285 * Such nodes return tuples of values. From these individual values can be
286 * extracted by proj nodes.
288 * The following example illustrates the construction of a simple basic block
289 * with two predecessors stored in variables cf_pred1 and cf_pred2, containing
292 * and finally jumping to an other block. The variable a got the local_val_nr
293 * 42 by the frontend.
295 * ir_node *this_block, *cf_pred1, *cf_pred2, *a_val, *mem, *div, *res, *cf_op;
297 * this_block = new_immBlock();
298 * add_in_edge(this_block, cf_pred1);
299 * add_in_edge(this_block, cf_pred2);
300 * mature_block(this_block);
301 * a_val = get_value(42, mode_I);
303 * div = new_Div(mem, a_val, a_val);
304 * mem = new_Proj(div, mode_M, 0); * for the numbers for Proj see docu *
305 * res = new_Proj(div, mode_I, 2);
307 * set_value(res, 42);
310 * For further information look at the documentation of the nodes and
311 * constructors and at the paragraph COPING WITH DATA OBJECTS at the
312 * end of this documentation.
314 * The comfortable interface contains the following routines further explained
317 * ir_node *new_immBlock (void);
318 * ir_node *new_Start (void);
319 * ir_node *new_End (void);
320 * ir_node *new_Jmp (void);
321 * ir_node *new_Cond (ir_node *c);
322 * ir_node *new_Return (ir_node *store, int arity, ir_node **in);
323 * ir_node *new_Raise (ir_node *store, ir_node *obj);
324 * ir_node *new_Const (ir_mode *mode, tarval *con);
325 * ir_node *new_SymConst (type_or_id *value, symconst_kind kind);
326 * ir_node *new_simpleSel (ir_node *store, ir_node *objptr, entity *ent);
327 * ir_node *new_Sel (ir_node *store, ir_node *objptr, int arity,
328 * ir_node **in, entity *ent);
329 * ir_node *new_Call (ir_node *store, ir_node *callee, int arity,
330 * ir_node **in, type_method *type);
331 * ir_node *new_Add (ir_node *op1, ir_node *op2, ir_mode *mode);
332 * ir_node *new_Sub (ir_node *op1, ir_node *op2, ir_mode *mode);
333 * ir_node *new_Minus (ir_node *op, ir_mode *mode);
334 * ir_node *new_Mul (ir_node *op1, ir_node *op2, ir_mode *mode);
335 * ir_node *new_Quot (ir_node *memop, ir_node *op1, ir_node *op2);
336 * ir_node *new_DivMod (ir_node *memop, ir_node *op1, ir_node *op2);
337 * ir_node *new_Div (ir_node *memop, ir_node *op1, ir_node *op2);
338 * ir_node *new_Mod (ir_node *memop, ir_node *op1, ir_node *op2);
339 * ir_node *new_Abs (ir_node *op, ir_mode *mode);
340 * ir_node *new_And (ir_node *op1, ir_node *op2, ir_mode *mode);
341 * ir_node *new_Or (ir_node *op1, ir_node *op2, ir_mode *mode);
342 * ir_node *new_Eor (ir_node *op1, ir_node *op2, ir_mode *mode);
343 * ir_node *new_Not (ir_node *op, ir_mode *mode);
344 * ir_node *new_Shl (ir_node *op, ir_node *k, ir_mode *mode);
345 * ir_node *new_Shr (ir_node *op, ir_node *k, ir_mode *mode);
346 * ir_node *new_Shrs (ir_node *op, ir_node *k, ir_mode *mode);
347 * ir_node *new_Rot (ir_node *op, ir_node *k, ir_mode *mode);
348 * ir_node *new_Cmp (ir_node *op1, ir_node *op2);
349 * ir_node *new_Conv (ir_node *op, ir_mode *mode);
350 * ir_node *new_Load (ir_node *store, ir_node *addr);
351 * ir_node *new_Store (ir_node *store, ir_node *addr, ir_node *val);
352 * ir_node *new_Alloc (ir_node *store, ir_node *size, type *alloc_type,
353 * where_alloc where);
354 * ir_node *new_Free (ir_node *store, ir_node *ptr, ir_node *size,
356 * ir_node *new_Proj (ir_node *arg, ir_mode *mode, long proj);
358 * void add_in_edge (ir_node *block, ir_node *jmp);
359 * void mature_block (ir_node *block);
360 * void switch_block (ir_node *target);
361 * ir_node *get_value (int pos, ir_mode *mode);
362 * void set_value (int pos, ir_node *value);
363 * ir_node *get_store (void);
364 * void set_store (ir_node *store);
367 * IR_NODES AND CONSTRUCTORS FOR IR_NODES
368 * =======================================
370 * All ir_nodes are defined by a common data structure. They are distinguished
371 * by their opcode and differ in the number of their attributes.
373 * The constructor for the block node sets current_block to itself.
374 * Const nodes are always added to the start block.
375 * All other constructors add the created node to the current_block.
376 * swich_block(block) allows to set the current block to block.
378 * Watch for my inconsistent use of input and predecessor (dataflow view)
379 * and `the node points to' (implementation view).
381 * The following description of the nodes lists four properties them if these
383 * - the parameters to the constructor
384 * - the inputs of the Firm node
385 * - the outputs of the Firm node
386 * - attributes to the node
391 * ir_node *new_immBlock (void)
392 * ----------------------------
394 * Creates a new block. Sets current_block to itself. When a new block is
395 * created it cannot be known how many predecessors this block will have in the
396 * control flow graph. Therefore the list of inputs can not be fixed at
397 * creation. Predecessors can be added with add_in_edge (block, control flow
398 * operation). With every added predecessor the number of inputs to Phi nodes
401 * The block can be completed by mature_block(block) if all predecessors are
402 * known. If several blocks are built at once, mature_block can only be called
403 * after set_value has been called for all values that are life at the end
404 * of the block. This is necessary so that Phi nodes created by mature_block
405 * get the right predecessors in case of cyclic dependencies. If all set_values
406 * of this block are called after maturing it and before calling get_value
407 * in some block that is control flow dependent on this block, the construction
410 * Example for faulty ir construction: (draw the graph on a paper and you'll
413 * block_before_loop = new_block();
415 * mature_block(block_before_loop);
416 * before2header = new_Jmp;
418 * loop_header = new_block ();
419 * header2body - new_Jmp();
421 * loop_body = new_block ();
422 * body2header = new_Jmp();
424 * add_in_edge(loop_header, before2header);
425 * add_in_edge(loop_header, body2header);
426 * add_in_edge(loop_body, header2body);
428 * mature_block(loop_header);
429 * mature_block(loop_body);
431 * get_value(loop_body, x); // gets the Phi in loop_header
432 * set_value(loop_header, x); // sets the value the above get_value should
433 * // have returned!!!
435 * Mature_block also fixes the number of inputs to the Phi nodes. Mature_block
436 * should be called as early as possible, as afterwards the generation of Phi
437 * nodes is more efficient.
440 * There is an input for each control flow predecessor of the block.
441 * The input points to an instruction producing an output of type X.
442 * Possible predecessors: Start, Jmp, Cond, Raise or Return or any node
443 * possibly causing an exception. (Often the real predecessors are Projs.)
445 * Mode BB (R), all nodes belonging to this block should consume this output.
446 * As they are strict (except Block and Phi node) it is a necessary condition
447 * that the block node executed before any other node in this block executes.
449 * block.matured Indicates whether the block is mature.
451 * This attribute contains all local values valid in this
452 * block. This is needed to build the Phi nodes and removed
453 * if the graph is complete. This field is used by the
454 * internal construction algorithm and should not be accessed
458 * ir_node *new_Block (int arity, ir_node **in)
459 * --------------------------------------------
461 * Creates a new Block with the given list of predecessors. This block
465 * CONTROL FLOW OPERATIONS
466 * -----------------------
468 * In each block there must be exactly one of the control flow
469 * operations Start, End, Jmp, Cond, Return or Raise. The output of a
470 * control flow operation points to the block to be executed next.
472 * ir_node *new_Start (void)
473 * -------------------------
475 * Creates a start node. Not actually needed public. There is only one such
476 * node in each procedure which is automatically created by new_ir_graph.
479 * No inputs except the block it belogns to.
481 * A tuple of 4 (5, 6) distinct values. These are labeled by the following
482 * projection numbers (pns_number):
484 * mode X, points to the first block to be executed.
486 * mode M, the global store
487 * * pns_frame_base mode P, a pointer to the base of the procedures
489 * * pns_globals mode P, a pointer to the part of the memory containing
490 * _all_ global things.
491 * * pns_args mode T, a tuple containing all arguments of the procedure.
494 * ir_node *new_End (void)
495 * -----------------------
497 * Creates an end node. Not actually needed public. There is only one such
498 * node in each procedure which is automatically created by new_ir_graph.
501 * No inputs except the block it belongs to.
505 * ir_node *new_Jmp (void)
506 * -----------------------
508 * Creates a Jmp node.
511 * The block the node belongs to
513 * Control flow to the next block.
515 * ir_node *new_Cond (ir_node *c)
516 * ------------------------------
518 * Creates a Cond node. There are two versions of this node.
524 * A tuple of two control flows. The first is taken if the input is
525 * false, the second if it is true.
529 * A value of mode I_u. (i)
531 * A tuple of n control flows. If the Cond's input is i, control
532 * flow will procede along output i. If the input is >= n control
533 * flow proceeds along output n.
535 * ir_node *new_Return (in_node *store, int arity, ir_node **in)
536 * -------------------------------------------------------------
538 * The return node has as inputs the results of the procedure. It
539 * passes the control flow to the end_block.
545 * Control flow to the end block.
547 * ir_node *new_Raise (ir_node *store, ir_node *obj)
548 * -------------------------------------------------
550 * Raises an exception. Unconditional change of control flow. Writes
551 * an explicit Except variable to memory to pass it to the exception
552 * handler. See TechReport 1999-14, chapter Exceptions.
556 * A pointer to the Except variable.
558 * A tuple of control flow and the changed memory state. The control flow
559 * points to the exception handler if it is definied in this procedure,
560 * else it points to the end_block.
566 * ir_node *new_Const (ir_mode *mode, tarval *con)
567 * -----------------------------------------------
569 * Creates a constant in the constant table and adds a Const node
570 * returning this value to the start block.
573 * *mode The mode of the constant.
574 * *con Points to an entry in the constant table.
575 * This pointer is added to the attributes of
576 * the node (self->attr.con)
578 * No inputs except the block it belogns to.
580 * The constant value.
582 * attr.con A tarval* pointer to the proper entry in the constant
585 * ir_node *new_SymConst (type *type, symconst_kind kind)
586 * ------------------------------------------------------------
588 * There are three kinds of symbolic constants:
589 * type_tag The symbolic constant represents a type tag.
590 * size The symbolic constant represents the size of a class.
591 * link_info Information for the linker, e.g. the name of a global
595 * kind The kind of the symbolic constant: type_tag, size or link_info.
596 * *type_or_id Points to the type the tag stands for or to the type
597 * whose size is represented by the constant or to an ident
598 * representing the linkage info.
601 * No inputs except the block it belogns to.
603 * An unsigned integer (I_u) or a pointer (P).
606 * attr.i.num The symconst_kind, i.e. one of
610 * If the attr.i.num is type_tag or size, the node contains an attribute
611 * attr.i.*type, a pointer to a type_class. The mode of the node is mode_i.
612 * if it is linkage_ptr_info it contains
613 * attr.i.*ptrinfo, an ident holding information for the linker. The mode
614 * of the node is mode_p.
619 * ir_node *new_simpleSel (ir_node *store, ir_node *frame, entity *sel)
620 * --------------------------------------------------------------------
623 * Selects an entity from a compound type. This entity can be a field or
627 * *store The memory in which the object the entity should be selected
629 * *frame The pointer to the object.
630 * *sel The entity to select.
633 * The memory containing the object.
634 * A pointer to the object.
635 * An unsigned integer.
637 * A pointer to the selected entity.
639 * attr.sel Pointer to the entity
642 * ir_node *new_Sel (ir_node *store, ir_node *frame, int arity, ir_node **in,
643 * --------------------------------------------------------------------------
647 * Selects a field from an array type. The entity has as owner the array, as
648 * type the arrays element type. The indexes to access an array element are
652 * *store The memory in which the object the entity should be selected from
654 * *frame The pointer to the object.
655 * *arity number of array indexes.
656 * *in array with index inputs to the node.
657 * *sel The entity to select.
660 * The memory containing the object.
661 * A pointer to the object.
662 * As much unsigned integer as there are array expressions.
664 * A pointer to the selected entity.
666 * attr.sel Pointer to the entity
668 * The constructors new_Sel and new_simpleSel generate the same ir nodes.
669 * simpleSel just sets the arity of the index inputs to zero.
672 * ARITHMETIC OPERATIONS
673 * ---------------------
675 * ir_node *new_Call (ir_node *store, ir_node *callee, int arity, ir_node **in,
676 * ----------------------------------------------------------------------------
680 * Creates a procedure call.
683 * *store The actual store.
684 * *callee A pointer to the called procedure.
685 * arity The number of procedure parameters.
686 * **in An array with the pointers to the parameters.
687 * The constructor copies this array.
688 * *type Type information of the procedure called.
691 * The store, the callee and the parameters.
693 * A tuple containing the eventually changed store and the procedure
696 * attr.call Contains the type information for the procedure.
698 * ir_node *new_Add (ir_node *op1, ir_node *op2, ir_mode *mode)
699 * ------------------------------------------------------------
703 * ir_node *new_Sub (ir_node *op1, ir_node *op2, ir_mode *mode)
704 * ------------------------------------------------------------
708 * ir_node *new_Minus (ir_node *op, ir_mode *mode)
709 * -----------------------------------------------
711 * Unary Minus operations on floating point values.
713 * ir_node *new_Mul (ir_node *op1, ir_node *op2, ir_mode *mode)
714 * ------------------------------------------------------------
718 * ir_node *new_Quot (ir_node *memop, ir_node *op1, ir_node *op2)
719 * --------------------------------------------------------------
721 * Quot performs exact division of floating point numbers. It's mode
722 * is Tuple, the mode of the result must be annotated to the Proj
723 * that extracts the result of the arithmetic operations.
726 * The store needed to model exceptions and the two operands.
728 * A tuple contaning a memory and a execution for modeling exceptions
729 * and the result of the arithmetic operation.
731 * ir_node *new_DivMod (ir_node *memop, ir_node *op1, ir_node *op2)
732 * ----------------------------------------------------------------
734 * Performs Div and Mod on interger values.
737 * A tuple contaning a memory and a execution for modeling exceptions
738 * and the two result of the arithmetic operations.
740 * ir_node *new_Div (ir_node *memop, ir_node *op1, ir_node *op2)
741 * -------------------------------------------------------------
745 * ir_node *new_Mod (ir_node *memop, ir_node *op1, ir_node *op2)
746 * -------------------------------------------------------------
750 * ir_node *new_Abs (ir_node *op, ir_mode *mode)
751 * ---------------------------------------------
755 * ir_node *new_And (ir_node *op1, ir_node *op2, ir_mode *mode)
756 * ------------------------------------------------------------
760 * ir_node *new_Or (ir_node *op1, ir_node *op2, ir_mode *mode)
761 * -----------------------------------------------------------
765 * ir_node *new_Eor (ir_node *op1, ir_node *op2, ir_mode *mode)
766 * ------------------------------------------------------------
770 * ir_node *new_Not (ir_node *op, ir_mode *mode)
771 * ---------------------------------------------
773 * This node constructs a constant where all bits are set to one
774 * and a Eor of this constant and the operator. This simulates a
777 * ir_node *new_Shl (ir_node *op, ir_node *k, ir_mode *mode)
778 * ---------------------------------------------------------
782 * ir_node *new_Shr (ir_node *op, ir_node *k, ir_mode *mode)
783 * ---------------------------------------------------------
785 * Logic shift right, i.e., zero extended.
788 * ir_node *new_Shrs (ir_node *op, ir_node *k, ir_mode *mode)
789 * ----------------------------------------------------------
791 * Arithmetic shift right, i.e., sign extended.
793 * ir_node *new_Rot (ir_node *op, ir_node *k, ir_mode *mode)
794 * ---------------------------------------------------------
796 * Rotates the operand to the (right??) by k bits.
798 * ir_node *new_Conv (ir_node *op, ir_mode *mode)
799 * ---------------------------------------------
801 * Mode conversion. For allowed conversions see UKA Tech Report
804 * ir_node *new_Cmp (ir_node *op1, ir_node *op2)
805 * ---------------------------------------------
808 * The two values to be compared.
810 * A 16-tuple containing the results of the 16 different comparisons.
811 * The following is a list giving the comparisons and a projection
812 * number (pnc_number) to use in Proj nodes to extract the proper result.
818 * Ge greater of equal
820 * Leg less, equal or greater = ordered
822 * Ue unordered or equal
823 * Ul unordered or less
824 * Ule unordered, less or equal
825 * Ug unordered or greater
826 * Uge unordered, greater or equal
827 * Ne unordered, less or greater = not equal
835 * In general, Phi nodes are automaitcally inserted. In some cases, if
836 * all predecessors of a block are known, an explicit Phi node constructor
837 * is needed. E.g., to construct a FIRM graph for a statement as
838 * a = (b==c) ? 2 : 5;
840 * ir_node *new_Phi (int arity, ir_node **in, ir_mode *mode)
841 * ---------------------------------------------------------
843 * Creates a Phi node. The in's order has to correspond to the order
844 * of in's of current_block. This is not checked by the library!
847 * arity number of predecessors
848 * **in array with predecessors
849 * *mode The mode of it's inputs and output.
851 * A Phi node has as many inputs as the block it belongs to.
852 * Each input points to a definition of the same value on a
853 * different path in the control flow.
855 * The definition valid in this block.
858 * OPERATIONS TO MANAGE MEMORY EXPLICITLY
859 * --------------------------------------
861 * ir_node *new_Load (ir_node *store, ir_node *addr)
862 * ----------------------------------------------------------------
864 * The Load operation reads a value from memory.
867 * *store The current memory.
868 * *addr A pointer to the variable to be read in this memory.
871 * The memory and a pointer to a variable in this memory.
873 * A tuple of the memory, a control flow to be taken in case of
874 * an exception and the loaded value.
876 * ir_node *new_Store (ir_node *store, ir_node *addr, ir_node *val)
877 * ----------------------------------------------------------------
879 * The Store operation writes a value to a variable in memory.
882 * The memory, a pointer to a variable in this memory and the value
883 * to write to this variable.
885 * A tuple of the changed memory and a control flow to be taken in
886 * case of an exception.
888 * ir_node *new_Alloc (ir_node *store, ir_node *size, type *alloc_type,
889 * --------------------------------------------------------------------
893 * The Alloc node allocates a new variable. It can be specified whether the
894 * variable should be allocated to the stack or to the heap.
897 * *store The memory which shall contain the new variable.
898 * ** *size The number of bytes to allocate. Old. **
899 * *size We decided that the size easily can be derived from the type.
900 * This field is for allocating arrays, i.e., it gives the multiple
901 * of the size of alloc_type to allocate memory for.
902 * *alloc_type The type of the allocated variable.
903 * where Where to allocate the variable, either heap_alloc or stack_alloc.
906 * A memory and an unsigned integer.
908 * A tuple of the changed memory, a control flow to be taken in
909 * case of an exception and the pointer to the new variable.
911 * a.where Indicates where the variable is allocated.
912 * a.*type A pointer to the class the allocated data object
915 * ir_node *new_Free (ir_node *store, ir_node *ptr, type *free_type)
916 * ------------------------------------------------------------------
918 * The Free node frees memory of the given variable.
921 * *store The memory which shall contain the new variable.
922 * *ptr The pointer to the object to free.
923 * *size The number of objects of type free_type to free in a sequence.
924 * *free_type The type of the freed variable.
927 * A memory, a pointer and an unsigned integer.
929 * The changed memory.
931 * f.*type A pointer to the type information of the freed data object.
935 * ir_node *new_Sync (int arity, ir_node **in)
936 * -------------------------------------------
938 * The Sync operation unifies several partial memory blocks. These blocks
939 * have to be pairwise disjunct or the values in common locations have to
940 * be identical. This operation allows to specify all operations that eventually
941 * need several partial memory blocks as input with a single entrance by
942 * unifying the memories with a preceding Sync operation.
945 * arity The number of memories to syncronize.
946 * **in An array of pointers to nodes that produce an output of
951 * The unified memory.
957 * ir_node *new_Bad (void)
958 * -----------------------
960 * Returns the unique Bad node current_ir_graph->bad.
961 * This node is used to express results of dead code elimination.
963 * ir_node *new_Proj (ir_node *arg, ir_mode *mode, long proj)
964 * ----------------------------------------------------------
966 * Selects one entry of a tuple. This is a hidden `fat edge'.
969 * *arg A node producing a tuple.
970 * *mode The mode of the value to project.
971 * proj The position of the value in the tuple.
977 * ir_node *new_Tuple (int arity, ir_node **in)
978 * --------------------------------------------
980 * Builds a Tuple from single values. This is needed to implement
981 * optimizations that remove a node that produced a tuple. The node can be
982 * replaced by the Tuple operation so that the following Proj nodes have not to
983 * be changed. (They are hard to find due to the implementation with pointers
984 * in only one direction.) The Tuple node is smaller than any other
985 * node, so that a node can be changed into a Tuple by just changing it's
986 * opcode and giving it a new in array.
989 * arity The number of tuple elements.
990 * **in An array containing pointers to the nodes producing the
993 * ir_node *new_Id (ir_node *val, ir_mode *mode)
994 * ---------------------------------------------
996 * The single output of the Id operation is it's input. Also needed
1000 * COPING WITH DATA OBJECTS
1001 * ========================
1003 * Two kinds of data objects have to be distinguished for generating
1004 * FIRM. First there are local variables other than arrays that are
1005 * known to be alias free. Second there are all other data objects.
1006 * For the first a common SSA representation is built, the second
1007 * are modeled by saving them to memory. The memory is treated as
1008 * a single local variable, the alias problem is hidden in the
1009 * content of this variable.
1011 * All values known in a Block are listed in the block's attribute,
1012 * block.**graph_arr which is used to automatically insert Phi nodes.
1013 * The following two funcions can be used to add a newly computed value
1014 * to the array, or to get the producer of a value, i.e., the current
1017 * inline void set_value (int pos, ir_node *value)
1018 * -----------------------------------------------
1020 * Has to be called for every assignment to a local variable. It
1021 * adds the value to the array of used values at position pos. Pos
1022 * has to be a unique identifier for an entry in the procedure's
1023 * definition table. It can be used to access the value again.
1024 * Requires current_block to be set correctly.
1026 * ir_node *get_value (int pos, ir_mode *mode)
1027 * -------------------------------------------
1029 * Returns the node defining the value referred to by pos. If the
1030 * value is not defined in this block a Phi node is generated and
1031 * all definitions reaching this Phi node are collected. It can
1032 * happen that the algorithm allocates an unnecessary Phi node,
1033 * e.g. if there is only one definition of this value, but this
1034 * definition reaches the currend block on several different
1035 * paths. This Phi node will be eliminated if optimizations are
1036 * turned on right after it's creation.
1037 * Requires current_block to be set correctly.
1039 * There are two special routines for the global store:
1041 * inline void set_store (ir_node *store)
1042 * --------------------------------------
1044 * Adds the store to the array of known values at a reserved
1046 * Requires current_block to be set correctly.
1048 * inline ir_node *get_store (void)
1049 * --------------------------------
1051 * Returns the node defining the actual store.
1052 * Requires current_block to be set correctly.
1060 # include "common.h"
1061 # include "irgraph.h"
1062 # include "irnode.h"
1063 # include "irmode.h"
1064 # include "entity.h"
1068 /***************************************************************************/
1069 /* The raw interface */
1070 /***************************************************************************/
1072 /* Constructs a Block with a fixed number of predecessors.
1073 Does not set current_block. Can not be used with automatic
1074 Phi node construction. */
1075 ir_node *new_r_Block (ir_graph *irg, int arity, ir_node **in);
1076 ir_node *new_r_Start (ir_graph *irg, ir_node *block);
1077 ir_node *new_r_End (ir_graph *irg, ir_node *block);
1078 ir_node *new_r_Jmp (ir_graph *irg, ir_node *block);
1079 ir_node *new_r_Cond (ir_graph *irg, ir_node *block, ir_node *c);
1080 ir_node *new_r_Return (ir_graph *irg, ir_node *block,
1081 ir_node *store, int arity, ir_node **in);
1082 ir_node *new_r_Raise (ir_graph *irg, ir_node *block,
1083 ir_node *store, ir_node *obj);
1084 ir_node *new_r_Const (ir_graph *irg, ir_node *block,
1085 ir_mode *mode, tarval *con);
1086 ir_node *new_r_SymConst (ir_graph *irg, ir_node *block,
1087 type_or_id_p value, symconst_kind symkind);
1088 ir_node *new_r_Sel (ir_graph *irg, ir_node *block, ir_node *store,
1089 ir_node *objptr, int n_index, ir_node **index,
1091 ir_node *new_r_Call (ir_graph *irg, ir_node *block, ir_node *store,
1092 ir_node *callee, int arity, ir_node **in,
1094 ir_node *new_r_Add (ir_graph *irg, ir_node *block,
1095 ir_node *op1, ir_node *op2, ir_mode *mode);
1096 ir_node *new_r_Sub (ir_graph *irg, ir_node *block,
1097 ir_node *op1, ir_node *op2, ir_mode *mode);
1098 ir_node *new_r_Minus (ir_graph *irg, ir_node *block,
1099 ir_node *op, ir_mode *mode);
1100 ir_node *new_r_Mul (ir_graph *irg, ir_node *block,
1101 ir_node *op1, ir_node *op2, ir_mode *mode);
1102 ir_node *new_r_Quot (ir_graph *irg, ir_node *block,
1103 ir_node *memop, ir_node *op1, ir_node *op2);
1104 ir_node *new_r_DivMod (ir_graph *irg, ir_node *block,
1105 ir_node *memop, ir_node *op1, ir_node *op2);
1106 ir_node *new_r_Div (ir_graph *irg, ir_node *block,
1107 ir_node *memop, ir_node *op1, ir_node *op2);
1108 ir_node *new_r_Mod (ir_graph *irg, ir_node *block,
1109 ir_node *memop, ir_node *op1, ir_node *op2);
1110 ir_node *new_r_Abs (ir_graph *irg, ir_node *block,
1111 ir_node *op, ir_mode *mode);
1112 ir_node *new_r_And (ir_graph *irg, ir_node *block,
1113 ir_node *op1, ir_node *op2, ir_mode *mode);
1114 ir_node *new_r_Or (ir_graph *irg, ir_node *block,
1115 ir_node *op1, ir_node *op2, ir_mode *mode);
1116 ir_node *new_r_Eor (ir_graph *irg, ir_node *block,
1117 ir_node *op1, ir_node *op2, ir_mode *mode);
1118 ir_node *new_r_Not (ir_graph *irg, ir_node *block,
1119 ir_node *op, ir_mode *mode);
1120 ir_node *new_r_Cmp (ir_graph *irg, ir_node *block,
1121 ir_node *op1, ir_node *op2);
1122 ir_node *new_r_Shl (ir_graph *irg, ir_node *block,
1123 ir_node *op, ir_node *k, ir_mode *mode);
1124 ir_node *new_r_Shr (ir_graph *irg, ir_node *block,
1125 ir_node *op, ir_node *k, ir_mode *mode);
1126 ir_node *new_r_Shrs (ir_graph *irg, ir_node *block,
1127 ir_node *op, ir_node *k, ir_mode *mode);
1128 ir_node *new_r_Rot (ir_graph *irg, ir_node *block,
1129 ir_node *op, ir_node *k, ir_mode *mode);
1130 ir_node *new_r_Conv (ir_graph *irg, ir_node *block,
1131 ir_node *op, ir_mode *mode);
1132 ir_node *new_r_Phi (ir_graph *irg, ir_node *block, int arity,
1133 ir_node **in, ir_mode *mode);
1134 ir_node *new_r_Load (ir_graph *irg, ir_node *block,
1135 ir_node *store, ir_node *adr);
1136 ir_node *new_r_Store (ir_graph *irg, ir_node *block,
1137 ir_node *store, ir_node *adr, ir_node *val);
1138 ir_node *new_r_Alloc (ir_graph *irg, ir_node *block, ir_node *store,
1139 ir_node *size, type *alloc_type, where_alloc where);
1140 ir_node *new_r_Free (ir_graph *irg, ir_node *block, ir_node *store,
1141 ir_node *ptr, ir_node *size, type *free_type);
1142 ir_node *new_r_Sync (ir_graph *irg, ir_node *block, int arity, ir_node **in);
1143 ir_node *new_r_Proj (ir_graph *irg, ir_node *block, ir_node *arg,
1144 ir_mode *mode, long proj);
1145 ir_node *new_r_defaultProj (ir_graph *irg, ir_node *block, ir_node *arg,
1147 ir_node *new_r_Tuple (ir_graph *irg, ir_node *block,
1148 int arity, ir_node **in);
1149 ir_node *new_r_Id (ir_graph *irg, ir_node *block,
1150 ir_node *val, ir_mode *mode);
1151 ir_node *new_r_Bad ();
1154 /*************************************************************************/
1155 /* The block oriented interface */
1156 /*************************************************************************/
1158 /* Sets the current block in which the following constructors place the
1159 nodes they construct. */
1160 void switch_block (ir_node *target);
1162 /* Constructs a Block with a fixed number of predecessors.
1163 Does set current_block. Can be used with automatic Phi
1164 node construction. */
1165 ir_node *new_Block(int arity, ir_node **in);
1166 ir_node *new_Start (void);
1167 ir_node *new_End (void);
1168 ir_node *new_Jmp (void);
1169 ir_node *new_Cond (ir_node *c);
1170 ir_node *new_Return (ir_node *store, int arity, ir_node **in);
1171 ir_node *new_Raise (ir_node *store, ir_node *obj);
1172 ir_node *new_Const (ir_mode *mode, tarval *con);
1173 ir_node *new_SymConst (type_or_id_p value, symconst_kind kind);
1174 ir_node *new_simpleSel(ir_node *store, ir_node *objptr, entity *ent);
1175 ir_node *new_Sel (ir_node *store, ir_node *objptr, int arity, ir_node **in,
1177 ir_node *new_Call (ir_node *store, ir_node *callee, int arity, ir_node **in,
1179 ir_node *new_Add (ir_node *op1, ir_node *op2, ir_mode *mode);
1180 ir_node *new_Sub (ir_node *op1, ir_node *op2, ir_mode *mode);
1181 ir_node *new_Minus (ir_node *op, ir_mode *mode);
1182 ir_node *new_Mul (ir_node *op1, ir_node *op2, ir_mode *mode);
1183 ir_node *new_Quot (ir_node *memop, ir_node *op1, ir_node *op2);
1184 ir_node *new_DivMod (ir_node *memop, ir_node *op1, ir_node *op2);
1185 ir_node *new_Div (ir_node *memop, ir_node *op1, ir_node *op2);
1186 ir_node *new_Mod (ir_node *memop, ir_node *op1, ir_node *op2);
1187 ir_node *new_Abs (ir_node *op, ir_mode *mode);
1188 ir_node *new_And (ir_node *op1, ir_node *op2, ir_mode *mode);
1189 ir_node *new_Or (ir_node *op1, ir_node *op2, ir_mode *mode);
1190 ir_node *new_Eor (ir_node *op1, ir_node *op2, ir_mode *mode);
1191 ir_node *new_Not (ir_node *op, ir_mode *mode);
1192 ir_node *new_Shl (ir_node *op, ir_node *k, ir_mode *mode);
1193 ir_node *new_Shr (ir_node *op, ir_node *k, ir_mode *mode);
1194 ir_node *new_Shrs (ir_node *op, ir_node *k, ir_mode *mode);
1195 ir_node *new_Rot (ir_node *op, ir_node *k, ir_mode *mode);
1196 ir_node *new_Cmp (ir_node *op1, ir_node *op2);
1197 ir_node *new_Conv (ir_node *op, ir_mode *mode);
1198 ir_node *new_Phi (int arity, ir_node **in, ir_mode *mode);
1199 ir_node *new_Load (ir_node *store, ir_node *addr);
1200 ir_node *new_Store (ir_node *store, ir_node *addr, ir_node *val);
1201 ir_node *new_Alloc (ir_node *store, ir_node *size, type *alloc_type,
1203 ir_node *new_Free (ir_node *store, ir_node *ptr, ir_node *size,
1205 ir_node *new_Sync (int arity, ir_node **in);
1206 ir_node *new_Proj (ir_node *arg, ir_mode *mode, long proj);
1207 ir_node *new_defaultProj (ir_node *arg, long max_proj);
1208 ir_node *new_Tuple (int arity, ir_node **in);
1209 ir_node *new_Id (ir_node *val, ir_mode *mode);
1210 ir_node *new_Bad (void);
1212 /***********************************************************************/
1213 /* The comfortable interface. */
1214 /* Supports automatic Phi node construction. */
1215 /* All routines of the block oriented interface except new_Block are */
1217 /***********************************************************************/
1219 /** Block construction **/
1220 /* immature Block without predecessors */
1221 ir_node *new_immBlock (void);
1223 /* Add a control flow edge to an immature block. */
1224 void add_in_edge (ir_node *immblock, ir_node *jmp);
1226 /* fixes the number of predecessors of a block. */
1227 void mature_block (ir_node *block);
1229 /** Parameter administration **/
1230 /* Read a value from the array with the local variables. Use this
1231 function to obtain the last definition of the value associated with
1232 pos. Pos may not exceed the value passed as n_loc to new_ir_graph. */
1233 ir_node *get_value (int pos, ir_mode *mode);
1235 /* Write a value in the array with the local variables. Use this function
1236 to remember a new definition of the value associated with pos. Pos may
1237 not exceed the value passed as n_loc to new_ir_graph. */
1238 void set_value (int pos, ir_node *value);
1241 Use this function to get the most recent version of the store (type M).
1242 Internally it does the same as get_value. */
1243 ir_node *get_store (void);
1245 /* Write a store. */
1246 void set_store (ir_node *store);
1248 /***********************************************************************/
1249 /* initialize ir construction */
1250 /***********************************************************************/
1251 void init_cons (void);
1254 # endif /* _IRCONS_H_ */