2018-03-02 Richard Biener <rguenther@suse.de>

2018-03-02  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/84427
	* tree-ssa-pre.c (bitmap_remove_expr_from_set): Remove.
	(bitmap_set_subtract_values): Rewrite to handle multiple
	exprs per value.
	(clean): Likewise.
	(prune_clobbered_mems): Likewise.
	(phi_translate): Take edge instead of pred/phiblock.
	(phi_translate_1): Likewise.
	(phi_translate_set): Likewise.  Insert all translated
	exprs for a value into the set, keeping possibly multiple
	expressions per value.
	(compute_antic_aux): Adjust for phi_translate changes.
	When intersecting union the expressions and prune those
	not in the final value set, keeping possibly multiple
	expressions per value.  Do not use value-insertion
	for unioning ANTIC_OUT U EXP_GEN - TMP_GEN but merge
	all expressions.  Add verification that the value-sets
	only shrink during iteration.
	(compute_partial_antic_aux): Adjust for the phi_translate changes.
	(do_pre_regular_insertion): Likewise.
	(do_pre_partial_partial_insertion): Likewise.

	* gcc.dg/torture/pr84427.c: New testcase.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@258124 138bc75d-0d04-0410-961f-82ee72b054a4