cfganal.h (rev_post_order_and_mark_dfs_back_seme): Declare.

cfganal.h (rev_post_order_and_mark_dfs_back_seme): Declare.

2018-08-27  Richard Biener  <rguenther@suse.de>

	* cfganal.h (rev_post_order_and_mark_dfs_back_seme): Declare.
	* cfganal.c (rev_post_order_and_mark_dfs_back_seme): New function.

	* tree-ssa-sccvn.h (struct vn_pval): New structure.
	(struct vn_nary_op_s): Add unwind_to member.  Add
	predicated_values flag and put result into a union together
	with a linked list of vn_pval.
	(struct vn_ssa_aux): Add name member to make maintaining
	a map of SSA name to vn_ssa_aux possible.  Remove no longer
	needed info, dfsnum, low, visited, on_sccstack, use_processed
	and range_info_anti_range_p members.
	(run_scc_vn, vn_eliminate, free_scc_vn, vn_valueize): Remove.
	(do_rpo_vn, run_rpo_vn, eliminate_with_rpo_vn, free_rpo_vn):
	New functions.
	(vn_valueize): New global.
	(vn_context_bb): Likewise.
	(VN_INFO_RANGE_INFO, VN_INFO_ANTI_RANGE_P, VN_INFO_RANGE_TYPE,
	VN_INFO_PTR_INFO): Remove.
	* tree-ssa-sccvn.c: ... (rewrite)
	(pass_fre::execute): For -O2+ initialize loops and run
	RPO VN in optimistic mode (iterating).  For -O1 and -Og
	run RPO VN in non-optimistic mode.
	* params.def (PARAM_SCCVN_MAX_SCC_SIZE): Remove.
	(PARAM_RPO_VN_MAX_LOOP_DEPTH): Add.
	* doc/invoke.texi (sccvn-max-scc-size): Remove.
	(rpo-vn-max-loop-depth): Document.
	* tree-ssa-alias.c (walk_non_aliased_vuses): Stop walking
	when valuezing the VUSE signals we walked out of the region.
	* tree-ssa-pre.c (phi_translate_1): Ignore predicated values.
	(phi_translate): Set VN context block to use for availability
	lookup.
	(compute_avail): Likewise.
	(pre_valueize): New function.
	(pass_pre::execute): Adjust to the RPO VN API.

	* tree-ssa-loop-ivcanon.c: Include tree-ssa-sccvn.h.
	(propagate_constants_for_unrolling): Remove.
	(tree_unroll_loops_completely): Perform value-numbering
	on the unrolled bodies loop parent.

	* g++.dg/torture/20180705-1.C: New testcase.
	* gcc.dg/tree-ssa/ssa-fre-67.c: Likewise.
	* gcc.dg/tree-ssa/ssa-ccp-14.c: Scan FRE dump.
	* gcc.dg/tree-ssa/ssa-fre-46.c: Use -O2.
	* gcc.dg/tree-ssa/vrp92.c: Disable FRE.
	* gcc.dg/pr83666.c: Drop --param=sccvn-max-scc-size option.
	* gcc.dg/pr85195.c: Likewise.
	* gcc.dg/pr85467.c: Likewise.
	* gcc.dg/torture/pr81790.c: Likewise.

	* gfortran.dg/reassoc_4.f: Change max-completely-peeled-insns
	param to current default.

From-SVN: r263875