* cgraph.h (cgraph_set_nothrow_flag, cgraph_set_readonly_flag,
	cgraph_set_pure_flag, cgraph_set_looping_const_or_pure_flag): New
	prototypes.
	* cgraph.c (cgraph_set_nothrow_flag, cgraph_set_readonly_flag,
	cgraph_set_pure_flag, cgraph_set_looping_const_or_pure_flag): New
	functions.
	* except.h (set_nothrow_function_flags): Remove prototype.
	* except.c (set_nothrow_function_flags): Use cgraph_set_nothrow_flag.
	Make static.
	* ipa-pure-const.c (propagate): Use cgraph_set_nothrow_flag,
	cgraph_set_readonly_flag, cgraph_set_pure_flag
	and cgraph_set_looping_const_or_pure_flag.
	(local_pure_const): Likewise.

From-SVN: r155220