2008-04-02 Richard Guenther <rguenther@suse.de>
PR tree-optimization/14495
PR tree-optimization/34793
* tree-vrp.c (struct switch_update): New structure.
(to_remove_edges, to_update_switch_stmts): New VECs.
(simplify_switch_using_ranges): New function. Remove not taken
case labels and edges.
(simplify_stmt_using_ranges): Call it.
(identify_jump_threads): Mark edges we have queued for removal
so we don't thread them.
(execute_vrp): Remove edges queued for removal, update SWITCH_STMT
case label vector.
* tree-cfg.c (group_case_labels): Deal with missing default label.
(tree_verify_flow_info): Allow missing default label.
* stmt.c (emit_case_bit_tests): Deal with NULL default_label.
(emit_case_nodes): Likewise.
(expand_case): Do not rely on the default label to be present.
* expr.c (try_casesi): Deal with NULL default_label.
(do_tablejump): Likewise.
* gcc.dg/tree-ssa/vrp41.c: New testcase.
* gcc.dg/tree-ssa/vrp42.c: Likewise.
From-SVN: r133835
