* tree-eh.h (unsplit_eh_edges): Declare.
	* tree-eh.c (maybe_remove_unreachable_handlers): Detect more cases.
	(unsplit_eh_edges): New function wrapping unsplit_all_eh.
	* gimple-ssa-store-merging.c: Include cfganal.h cfgcleanup.h except.h.
	(struct store_immediate_info): Add lp_nr field.
	(store_immediate_info::store_immediate_info): Add NR2 parameter and
	initialize lp_nr with it.
	(struct merged_store_group): Add lp_nr and only_constants fields.
	(merged_store_group::merged_store_group): Initialize them.
	(merged_store_group::can_be_merged_into): Deal with them.
	(pass_store_merging): Rename terminate_and_release_chain into
	terminate_and_process_chain.
	(pass_store_merging::terminate_and_process_all_chains): Adjust to above
	renaming and remove useless assertions.
	(pass_store_merging::terminate_all_aliasing_chains): Small tweak.
	(stmts_may_clobber_ref_p): Be prepared for different basic blocks.
	(imm_store_chain_info::coalesce_immediate_stores): Use only_constants
	instead of always recomputing it and compare lp_nr.
	(imm_store_chain_info::output_merged_store): If the group is in an
	active EH region, register new stores if they can throw.  Moreover,
	if the insertion has created new basic blocks, adjust the PHI nodes
	of the post landing pad.
	(imm_store_chain_info::output_merged_stores): If the original stores
	are in an active EH region, deregister them.
	(lhs_valid_for_store_merging_p): Prettify.
	(adjust_bit_pos): New function extracted from...
	(mem_valid_for_store_merging): ...here.  Use it for the base address
	and also for the offset if it is the addition of a constant.
	(lp_nr_for_store): New function.
	(pass_store_merging::process_store): Change return type to bool.
	Call lp_nr_for_store to initialize the store info.  Propagate the
	return status of various called functions to the return value.
	(store_valid_for_store_merging_p): New predicate.
	(enum basic_block_status): New enumeration.
	(get_status_for_store_merging): New function.
	(pass_store_merging::execute): If the function can throw and catch
	non-call exceptions, unsplit the EH edges on entry and clean up the
	CFG on exit if something changed.  Call get_status_for_store_merging
	for every basic block and keep the chains open across basic blocks
	when possible.  Terminate and process open chains at the end, if any.

From-SVN: r276459