1 /* (C) 1998 - 2000 by Universitaet Karlsruhe
2 ** All rights reserved.
4 ** Authors: Christian Schaefer, Goetz Lindenmaier
13 *** This file constructs the ir for the following pseudo-program:
16 *** int a = 0; // pos 0
17 *** int b = 1; // pos 1
23 *** while (0 == 0) loop {
41 ir_node *b, *x, *r, *t, *f;
43 printf("\nCreating an IR graph: IF_WHILE_EXAMPLE...\n");
46 turn_of_edge_labels();
49 set_opt_constant_folding(0); /* so that the stupid tests are not optimized. */
50 /* if optimized no path to End remains!! */
52 set_opt_dead_node_elimination (1);
54 /*** Make basic type information for primitive type int. ***/
55 prim_t_int = new_type_primitive(id_from_str ("int", 3), mode_I);
57 #define METHODNAME "main"
61 proc_main = new_type_method(id_from_str(METHODNAME, strlen(METHODNAME)),
63 set_method_res_type(proc_main, 0, prim_t_int);
64 owner = new_type_class (id_from_str ("IF_WHILE_EXAMPLE", 16));
65 ent = new_entity (owner, id_from_str ("main", 4), proc_main);
67 /* Generates start and end blocks and nodes and a first, initial block */
68 irg = new_ir_graph (ent, 4);
70 /* Generate two constants */
71 set_value (0, new_Const (mode_I, tarval_from_long (mode_I, 0)));
72 set_value (1, new_Const (mode_I, tarval_from_long (mode_I, 1)));
73 mature_block (get_irg_current_block(irg));
75 /* Generate a conditional branch */
78 /* generate the fall through block and add all cfg edges */
84 /* generate a block for the loop header and the conditional branch */
87 x = new_Cond (new_Proj(new_Cmp(new_Const (mode_I, tarval_from_long (mode_i, 0)),
88 new_Const (mode_I, tarval_from_long (mode_i, 0))),
90 f = new_Proj (x, mode_X, 0);
91 t = new_Proj (x, mode_X, 1);
93 /* generate the block for the loop body */
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_I));
104 set_value (0, get_value (1, mode_I));
105 set_value (1, get_value (2, mode_I));
108 /* generate the return block */
115 in[0] = new_Sub (get_value (0, mode_I), get_value (1, mode_I), mode_I);
117 x = new_Return (get_store (), 1, in);
120 /* finalize the end block generated in new_ir_graph() */
121 add_in_edge (get_irg_end_block(irg), x);
122 mature_block (get_irg_end_block(irg));
126 printf("Optimizing ...\n");
128 local_optimize_graph(irg);
129 dead_node_elimination(irg);
133 /* verify the graph */
136 /* output the vcg file */
137 printf("Done building the graph. Dumping it with out-edges.\n");
140 printf("Use xvcg to view this graph:\n");
141 printf("/ben/goetz/bin/xvcg GRAPHNAME\n\n");