1 /* Copyright (C) 1998 - 2000 by Universitaet Karlsruhe
2 ** All rights reserved.
4 ** Authors: Christian Schaefer, Goetz Lindenmaier
15 * das leere FIRM Programm
19 *** This file constructs the ir for the following pseudo-program:
26 int main(int argc, char **argv)
28 ir_graph *irg; /* this variable contains the irgraph */
29 type_class *owner; /* the class in which this method is defined */
30 type_method *proc_main; /* type information for the method main */
31 entity *ent; /* represents this method as entity of owner */
34 printf("creating an IR graph: EMPTY...\n");
39 set_opt_dead_node_elimination (o);
41 /* FIRM was designed for oo languages where all methods belong to a class.
42 * For imperative languages like C we view a file as a large class containing
43 * all functions as methods in this file.
44 * (Therefore we define a class "empty" according to the file name
45 * with a method main as an entity.)
46 * This class now is automatically generated.
48 #define METHODNAME "main"
52 owner = get_glob_type();
53 proc_main = new_type_method(id_from_str(METHODNAME, strlen(METHODNAME)),
55 ent = new_entity ((type *)owner,
56 id_from_str (METHODNAME, strlen(METHODNAME)),
59 /* Generates the basic graph for the method represented by entity ent, that
60 * is, generates start and end blocks and nodes and a first, initial block.
61 * The constructor needs to know how many local variables the method has.
63 #define NUM_OF_LOCAL_VARS 0
65 irg = new_ir_graph (ent, NUM_OF_LOCAL_VARS);
68 /* The constructor new_ir_graph() generated a region to place nodes in.
69 * This region is accessible via the attribut current_block of irg and
71 * Generate the return node into this region. The Return node is needed to
72 * return at least the store. */
74 ir_node *in[0]; /* this is the array containing the return parameters */
75 x = new_Return (get_store(), 0, in);
77 /* Now generate all instructions for this block and all its predecessor blocks
78 * so we can mature it. */
79 mature_block (irg->current_block);
81 /* This adds the in edge of the end block which originates at the return statement.
82 * The return node passes controlflow to the end block. */
83 add_in_edge (irg->end_block, x);
84 /* Now we can mature the end block as all it's predecessors are known. */
85 mature_block (irg->end_block);
87 /* verify the graph */
89 dead_node_elimination(irg);
91 printf("\nDone building the graph. Dumping it.\n");
92 dump_ir_block_graph (irg);
94 printf("use xvcg to view this graph:\n");
95 printf("/ben/goetz/bin/xvcg GRAPHNAME\n");