1 /* Copyright (C) 1998 - 2000 by Universitaet Karlsruhe
2 ** All rights reserved.
4 ** Author: Boris Boesler
6 ** traverse an ir graph
7 ** - execute the pre function before recursion
8 ** - execute the post function after recursion
10 ** Uses current_ir_graph (from irgraph.h)!!! Set it to the proper
11 ** graph before starting the walker.
21 /* type of callback function for ir_graph walk */
22 typedef void (* irg_walk_func)(ir_node *, void *);
24 /* Walks over the ir graph, starting at the node given as first argument.
25 Executes pre before visiting the predecessor of a node, post after.
26 irg_walk uses the visited flag in irg and the nodes to determine visited
27 nodes. It executes inc_irg_visited(current_ir_graph) to generate a new
28 flag. It marks the node as visited before executing pre.
29 The void* env can be used to pass status information between the
30 pre and post functions. */
31 void irg_walk(ir_node *node, irg_walk_func pre, irg_walk_func post, void *env);
33 /* Like "irg_walk", but walks over all reachable nodes in the ir
34 * graph, starting at the end operation. During the walk current_ir_graph
36 void irg_walk_graph(ir_graph *irg, irg_walk_func pre, irg_walk_func post, void *env);
38 /* Executes irg_walk(end, pre, post, env) for all irgraphs in irprog.
39 Sets current_ir_graph properly for each walk. Conserves current
41 void all_irg_walk(irg_walk_func pre, irg_walk_func post, void *env);
44 /* Walks only over Block nodes in the graph. Has it's own visited
45 flag, so that it can be interleaved with the other walker.
46 If a none block is passed, starts at the block this node belongs to.
47 If end is passed also visites kept alive blocks. */
48 void irg_block_walk(ir_node *node, irg_walk_func pre, irg_walk_func post, void *env);
50 /* Like "irg_block_walk", but walks over all reachable blocks in the
51 * ir graph, starting at the end block. */
52 void irg_block_walk_graph(ir_graph *irg, irg_walk_func pre, irg_walk_func post, void *env);
54 /********************************************************************/
55 /** Walking support for interprocedural analysis **/
57 /** @@@ Don't use, not operational yet, doesn't grok recursions!! **/
59 /** Interprocedural walking should not walk all predecessors of **/
60 /** all nodes. When leaving a procedure the walker should only **/
61 /** follow the edge corresponding to the most recent entry of the **/
62 /** procedure. The following functions use an internal stack to **/
63 /** remember the current call site of a procedure. **/
64 /** They also set current_ir_graph correctly. **/
66 /** Usage example: **/
68 /** void init_ip_walk (); **/
69 /** work_on_graph(some_end_node); **/
70 /** void finish_ip_walk(); **/
72 /** work_on_graph(ir_node *n) { **/
73 /** for (i = 0; i < get_irn_arity(n); i++) { **/
74 /** if (...) continue; **/
75 /** ir_node *m = get_irn_ip_pred(n, i); **/
76 /** if !m continue; **/
77 /** work_on_graph(m); **/
78 /** return_recur(n, i); **/
81 /********************************************************************/
83 /* Allocates some necessary datastructures. */
85 /* Frees some necessary datastructures. */
86 void finish_ip_walk();
88 /* Call for i in {0|-1 ... get_irn_arity(n)}.
89 If n is a conventional node returns the same node as get_irn_n(n, i).
90 If the predecessors of n are in the callee of the procedure n belongs
91 to, returns get_irn_n(n, i) if this node is in the callee on the top
92 of the stack, else returns NULL.
93 If the predecessors of n are in a procedure called by the procedure n
94 belongs to pushes the caller on the caller stack in the callee.
95 Sets current_ir_graph to the graph the node returned is in. */
96 ir_node *get_irn_ip_pred(ir_node *n, int pos);
98 /* If get_irn_ip_pred() returned a node (not NULL) this must be
99 called to clear up the stacks.
100 Sets current_ir_graph to the graph n is in. */
101 void return_recur(ir_node *n, int pos);
104 # endif /* _IRGWALK_H_ */