* tree-ssa-loop-ch.c: New file.
	* Makefile.in (tree-ssa-loop-ch.o): Add.
	(tree-into-ssa.o): Add GGC_H dependency.
	* tree-cfg.c (tree_duplicate_bb): Copy virtual arguments.
	* tree-flow.h (rewrite_into_ssa): Declaration changed.
	(rewrite_ssa_into_ssa, compute_global_livein, duplicate_ssa_name):
	Declare.
	* tree-into-ssa.c: Include ggc.h.
	(struct def_blocks_d): Add phi_blocks field.
	(struct mark_def_sites_global_data): Add names_to_rename field.
	(struct ssa_name_info): New.
	(compute_global_livein): Export.
	(set_def_block, insert_phi_nodes, mark_def_sites, set_livein_block,
	insert_phi_nodes_1, rewrite_finalize_block, insert_phi_nodes_for,
	register_new_def, get_reaching_def, def_blocks_free,
	get_def_blocks_for, rewrite_into_ssa): Modified to work with
	rewrite_ssa_into_ssa.
	(get_ssa_name_ann, get_phi_state, set_phi_state, get_current_def,
	set_current_def, ssa_mark_def_sites_initialize_block,
	ssa_mark_phi_uses, ssa_mark_def_sites, duplicate_ssa_name,
	ssa_register_new_def, ssa_rewrite_initialize_block,
	ssa_rewrite_phi_arguments, ssa_rewrite_finalize_block,
	ssa_rewrite_stmt, rewrite_ssa_into_ssa, rewrite_all_into_ssa): New
	functions.
	(pass_build_ssa): Call rewrite_all_into_ssa.
	* tree-optimize.c (execute_todo, execute_one_pass,
	tree_rest_of_compilation): Allocate vars_to_rename only once.
	* tree-ssa-dom.c (tree_ssa_dominator_optimize): Provide parameter
	to rewrite_into_ssa.
	* tree-ssa-loop.c (should_duplicate_loop_header_p,
	mark_defs_for_rewrite, duplicate_blocks, do_while_loop_p,
	copy_loop_headers, gate_ch, pass_ch): Moved to tree-ssa-loop-ch.c.
	Use rewrite_ssa_into_ssa.
	* tree-ssa-operands.c (copy_virtual_operands): New function.
	* tree-ssa-operands.h (copy_virtual_operands): Declare.
	* tree.h (struct tree_ssa_name): Add aux field.
	(SSA_NAME_AUX): New macro to access it.

From-SVN: r83932