2007-06-30  Daniel Berlin  <dberlin@dberlin.org>
	
	Fix PR tree-optimization/32540
	Fix PR tree-optimization/31651

	* tree-ssa-sccvn.c: New file.

	* tree-ssa-sccvn.h: Ditto.
	
	* tree-vn.c: Include tree-ssa-sccvn.h
	(val_expr_paid_d): Removed.
	(value_table): Ditto.
	(vn_compute): Ditto.
	(val_expr_pair_hash): Ditto.
	(val_expr_pair_expr_eq): Ditto.
	(copy_vuses_from_stmt): Ditto.
	(vn_delete): Ditto.
	(vn_init): Ditto.
	(shared_vuses_from_stmt): Ditto.
	(print_creation_to_file): Moved up.
	(sort_vuses): Ditto.
	(sort_vuses_heap): Ditto.
	(set_value_handle): Make non-static.
	(make_value_handle): Ditto.
	(vn_add): Rewritten to use sccvn lookups.
	(vn_add_with_vuses): Ditto.
	(vn_lookup): Ditto (and second argument removed).
	(vn_lookup_with_vuses): Ditto.
	(vn_lookup_or_add): Ditto (and second argument removed);
	(vn_lookup_or_add_with_vuses): Ditto.
	(vn_lookup_with_stmt): New.
	(vn_lookup_or_add_with_stmt): Ditto.
	(create_value_handle_for_expr): Ditto.

	* tree-ssa-pre.c: Include tree-ssa-sccvn.h.
	(seen_during_translate): New function.
	(phi_trans_lookup): Use iterative_hash_expr, not vn_compute.
	(phi_trans_add): Ditto.
	(constant_expr_p): FIELD_DECL is always constant.
	(phi_translate_1): Renamed from phi_translate, add seen bitmap.
	Use constant_expr_p.
	Avoid infinite recursion on mutually valued expressions.
	Change callers of vn_lookup_or_add.
	(phi_translate): New function.
	(compute_antic_safe): Allow phi nodes.
	(create_component_ref_by_pieces): Update for FIELD_DECL change.
	(find_or_generate_expression): Rewrite slightly.
	(create_expression_by_pieces): Updated for vn_lookup_or_add
	change.
	Update VN_INFO for new names.
	(insert_into_preds_of_block): Update for new names.
	(add_to_exp_gen): New function.
	(add_to_sets): Use vn_lookup_or_add_with_stmt.
	(find_existing_value_expr): Rewrite to changed vn_lookup.
	(create_value_expr_from): Ditto, and use add_to_exp_gen.
	(try_look_through_load): Removed.
	(try_combine_conversion): Ditto.
	(get_sccvn_value): New function.
	(make_values_for_phi): Ditto.
	(make_values_for_stmt): Ditto.
	(compute_avail): Rewritten for vn_lookup_or_add changes and to use
	SCCVN.
	(init_pre): Update for SCCVN changes.
	(fini_pre): Ditto.
	(execute_pre): Ditto.

	* tree-flow.h (make_value_handle): Declare.
	(set_value_handle): Ditto.
	(sort_vuses_heap): Ditto.
	(vn_lookup_or_add_with_stmt): Ditto.
	(vn_lookup_with_stmt): Ditto.
	(vn_compute): Remove.
	(vn_init): Ditto.
	(vn_delete): Ditto.
	(vn_lookup): Update arguments.

	* Makefile.in (tree-ssa-pre.o): Add tree-ssa-sccvn.h
	(tree-vn.o): Ditto.
	(tree-ssa-sccvn.o): New.
	(OBJS-common): Add tree-ssa-sccvn.o

From-SVN: r126149