3 * File name: testprograms/endless_loop.c
4 * Purpose: Representation of an endless loop.
5 * Author: Goetz Lindenmaier
9 * Copyright: (c) 1999-2003 Universität Karlsruhe
10 * Licence: This file protected by GPL - GNU GENERAL PUBLIC LICENSE.
16 #include <libfirm/firm.h>
19 * This file constructs the ir for the following pseudo-program:
21 * VAR_A is some extern variable.
23 * main(int a) { // pos 0
27 * while (0 == 0) loop {
41 char *dump_file_suffix = "";
47 ir_node *b, *x, *r, *t, *f;
48 union symconst_symbol symbol;
50 printf("\nCreating an IR graph: ENDLESS_LOOP_EXAMPLE...\n");
55 set_opt_constant_folding(1);
57 set_opt_global_cse(0);
59 prim_t_int = new_type_primitive(new_id_from_chars("int", 3), mode_Is);
61 #define METHODNAME "main_tp"
65 proc_main = new_type_method(new_id_from_chars(METHODNAME, strlen(METHODNAME)),
67 set_method_param_type(proc_main, 0, prim_t_int);
68 set_method_res_type(proc_main, 0, prim_t_int);
71 owner = new_type_class(new_id_from_chars("ENDLESS_LOOP_EXAMPLE", 20));
72 ent = new_entity(owner, new_id_from_chars("main", strlen("main")), proc_main);
73 get_entity_ld_name(ent); /* force name mangling */
75 /* Generates start and end blocks and nodes and a first, initial block */
76 irg = new_ir_graph(ent, 4);
78 /* Generate two values */
79 set_value(0, new_Proj(get_irg_args(irg), mode_Is, 0));
80 set_value(1, new_Const(mode_Is, new_tarval_from_long(1, mode_Is)));
83 mature_immBlock(get_irg_current_block(irg));
85 /* generate a block for the loop header and the conditional branch */
87 add_immBlock_pred(r, x);
88 x = new_Cond(new_Proj(new_Cmp(new_Const(mode_Is, new_tarval_from_long(0, mode_Is)),
89 new_Const(mode_Is, new_tarval_from_long(0, mode_Is))),
91 f = new_Proj(x, mode_X, pn_Cond_false);
92 t = new_Proj(x, mode_X, pn_Cond_true);
94 /* generate the block for the loop body */
96 add_immBlock_pred(b, t);
98 add_immBlock_pred(r, x);
100 /* The code in the loop body,
101 as we are dealing with local variables only the dataflow edges
103 set_value(2, get_value(0, mode_Is));
104 set_value(0, get_value(1, mode_Is));
105 set_value(1, get_value(2, mode_Is));
107 /* set VAR_A to constant value */
108 symbol.entity_p = new_entity(get_glob_type(),new_id_from_chars("VAR_A",6),prim_t_int);
109 set_store(new_Proj(new_Store(get_store(),
110 new_SymConst(mode_P, symbol, symconst_addr_ent),
111 get_value(1, mode_Is)),
112 mode_M, pn_Store_M));
117 /* generate the return block */
119 add_immBlock_pred(r, f);
124 in[0] = new_Sub(get_value(0, mode_Is), get_value(1, mode_Is), mode_Is);
126 x = new_Return(get_store(), 1, in);
129 /* finalize the end block generated in new_ir_graph() */
130 add_immBlock_pred(get_irg_end_block(irg), x);
131 mature_immBlock(get_irg_end_block(irg));
133 irg_finalize_cons(irg);
135 printf("Optimizing ...\n");
137 dead_node_elimination(irg);
138 local_optimize_graph(irg);
140 /* verify the graph */
143 /* output the vcg file */
144 printf("Done building the graph. Dumping it.\n");
145 /* turn_of_edge_labels(); */
146 dump_keepalive_edges(1);
147 dump_all_types(dump_file_suffix);
148 dump_ir_block_graph(irg, dump_file_suffix);
149 printf("Use ycomp to view this graph:\n");
150 printf("ycomp GRAPHNAME\n\n");