tree-ssa-structalias.c (callused_id, [...]): Add.

2008-06-28  Richard Guenther  <rguenther@suse.de>

	* tree-ssa-structalias.c (callused_id, var_callused,
	callused_tree): Add.
	(handle_pure_call): New function.
	(find_func_aliases): Call it.
	(find_what_p_points_to): Handle the call-used set.
	(clobber_what_escaped): Likewise.
	(compute_call_used_vars): New function.
	(init_base_vars): Init the call-used variable.
	(do_sd_constraint): Do not propagate the solution from CALLUSED
	but use CALLUSED as a placeholder.
	(solve_graph): Likewise.
	* tree-flow-inline.h (gimple_call_used_vars): New function.
	* tree-flow.h (struct gimple_df): Add call_used_vars bitmap.
	(compute_call_used_vars): Declare.
	* tree-ssa-alias.c (set_initial_properties): Call
	compute_call_used_vars.
	(reset_alias_info): Clear call-used variables.
	(add_call_clobber_ops): Assert we are not called for const/pure
	functions.  Remove handling of them.
	(add_call_read_ops): Handle pure functions by adding the
	call-used set of variables as VUSEs.
	* tree-ssa.c (init_tree_ssa): Allocate call-used bitmap.
	(delete_tree_ssa): Free it.
	* tree-dfa.c (remove_referenced_var): Clear the var from the
	call-used bitmap.

	* gcc.dg/tree-ssa/pr24287.c: Remove XFAIL.

From-SVN: r137222