show use of exceptions

[r3200]

diff --git a/testprograms/exception_example.c b/testprograms/exception_example.c
new file mode 100644 (file)
index 0000000..21687e4
--- /dev/null
+++ b/testprograms/exception_example.c
@@ -0,0 +1,142 @@
+/*
+ * Project:     libFIRM
+ * File name:   testprograms/exception.c
+ * Purpose:     Shows construction of exceptions.
+ *              Tests Phi construction.
+ * Author:      Goetz Lindenmaier
+ * Modified by:
+ * Created:
+ * CVS-ID:      $Id$
+ * Copyright:   (c) 2004 Universität Karlsruhe
+ * Licence:     This file protected by GPL -  GNU GENERAL PUBLIC LICENSE.
+ */
+
+# include <stdio.h>
+# include <string.h>
+
+# include "irvrfy.h"
+# include "firm.h"
+# include "irdump.h"
+
+
+/**
+*  This file constructs the ir for the following pseudo-program:
+*
+*  main() {
+*    int a = 5;  // val 0
+*    int b = 6;  // val 1
+*    int c = 7;  // val 2
+*    int d;      // val 3
+*
+*    try {
+*      d = a/0;
+*      c = 8;
+*      d = b/0
+*    } catch () { return c }
+*
+*    return d;
+**/
+
+int main(int argc, char **argv)
+{
+  type     *prim_t_int;
+  ir_graph *irg;       /* this variable contains the irgraph */
+  type     *owner;     /* the class in which this method is defined */
+  type     *method;    /* the type of this method */
+  entity   *ent;       /* represents this method as entity of owner */
+  ir_node  *x, *catch_block, *block, *zero, *a, *b, *c, *d;
+
+  printf("\nCreating an IR graph: EXCEPTION...\n");
+
+  /* init library */
+  init_firm (NULL);
+
+  /*** Make basic type information for primitive type int. ***/
+  prim_t_int = new_type_primitive(id_from_str ("int", 3), mode_Is);
+
+  /* FIRM was designed for oo languages where all methods belong to a class.
+   * For imperative languages like C we view a file as a large class containing
+   * all functions as methods in this file.
+   * Therefore we define a class "IF_ELSE_EXAMPLE" with a method main as an
+   * entity.
+   */
+#define ENTITYNAME "EXCEPTION_main"
+
+  owner = get_glob_type();
+  method = new_type_method (new_id_from_str(ENTITYNAME), 0, 1);
+  set_method_res_type(method, 0, prim_t_int);
+
+  ent = new_entity (owner, new_id_from_str (ENTITYNAME), method);
+
+  /* Generates the basic graph for the method represented by entity ent, that
+   * is, generates start and end blocks and nodes and a first, initial block.
+   * The constructor needs to know how many local variables the method has.
+   */
+#define NUM_OF_LOCAL_VARS 4
+
+  irg = new_ir_graph (ent, NUM_OF_LOCAL_VARS);
+
+  /* Initialize a, b, c. */
+  zero = new_Const (mode_Is, new_tarval_from_long (0, mode_Is));
+  a = new_Const (mode_Is, new_tarval_from_long (5, mode_Is));
+  b = new_Const (mode_Is, new_tarval_from_long (6, mode_Is));
+  c = new_Const (mode_Is, new_tarval_from_long (7, mode_Is));
+
+  /* set a and b to constants */
+  set_value (0, a);  /* this (0) is variable a */
+  set_value (1, b);  /* this (1) is variable b */
+  set_value (2, c);  /* this (2) is variable c */
+
+  block = get_cur_block();
+  catch_block = new_immBlock();
+  switch_block(block);
+
+  /* d = a / 0 */
+  d = new_Div(get_store(), get_value(0, mode_Is), zero);
+  set_store(new_Proj(d, mode_M, pn_Div_M));
+  x = new_Proj(d, mode_X, pn_Div_X_except);
+  add_in_edge(catch_block, x);
+  d = new_Proj(d, mode_Is, pn_Div_res);
+  set_value(3, d);  /* this (3) is variable d */
+
+  /* c = 8 */
+  c = new_Const (mode_Is, new_tarval_from_long (8, mode_Is));
+  set_value (2, c);  /* this (2) is variable c */
+
+  /* d = b / 0 */
+  d = new_Div(get_store(), get_value(1, mode_Is), zero);
+  set_store(new_Proj(d, mode_M, pn_Div_M));
+  x = new_Proj(d, mode_X, pn_Div_X_except);
+  add_in_edge(catch_block, x);
+  d = new_Proj(d, mode_Is, pn_Div_res);
+  set_value(3, d);  /* this (3) is variable d */
+
+  /* return d */
+  d = get_value(3, mode_Is);
+  x = new_Return (get_store(), 1, &d);
+  mature_block(get_cur_block());
+  add_in_edge(get_irg_end_block(current_ir_graph), x);
+
+  /* return c */
+  switch_block(catch_block);
+  c = get_value(2, mode_Is);
+  x = new_Return (get_store(), 1, &c);
+  mature_block(get_cur_block());
+  add_in_edge(get_irg_end_block(current_ir_graph), x);
+
+  /* Now we can mature the end block as all it's predecessors are known. */
+  mature_block (get_irg_end_block(irg));
+
+  finalize_cons (irg);
+
+  /* verify the graph */
+  irg_vrfy(irg);
+
+  printf("Done building the graph.  Dumping it.\n");
+  dump_ir_block_graph (irg);
+  dump_ir_graph (irg);
+  printf("use xvcg to view this graph:\n");
+  printf("/ben/goetz/bin/xvcg GRAPHNAME\n\n");
+
+  return (0);
+}