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

1 files changed, 9 insertions, 48 deletions

diff --git a/gcc/tree-ssa-loop-ivcanon.c b/gcc/tree-ssa-loop-ivcanon.c
index 326589f..97c2ad9 100644
--- a/gcc/tree-ssa-loop-ivcanon.c
+++ b/gcc/tree-ssa-loop-ivcanon.c
@@ -63,6 +63,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "tree-inline.h"
 #include "tree-cfgcleanup.h"
 #include "builtins.h"
+#include "tree-ssa-sccvn.h"
 
 /* Specifies types of loops that may be unrolled.  */
 
@@ -1318,50 +1319,6 @@ canonicalize_induction_variables (void)
   return 0;
 }
 
-/* Propagate constant SSA_NAMEs defined in basic block BB.  */
-
-static void
-propagate_constants_for_unrolling (basic_block bb)
-{
-  /* Look for degenerate PHI nodes with constant argument.  */
-  for (gphi_iterator gsi = gsi_start_phis (bb); !gsi_end_p (gsi); )
-    {
-      gphi *phi = gsi.phi ();
-      tree result = gimple_phi_result (phi);
-      tree arg = gimple_phi_arg_def (phi, 0);
-
-      if (! SSA_NAME_OCCURS_IN_ABNORMAL_PHI (result)
-	  && gimple_phi_num_args (phi) == 1
-	  && CONSTANT_CLASS_P (arg))
-	{
-	  replace_uses_by (result, arg);
-	  gsi_remove (&gsi, true);
-	  release_ssa_name (result);
-	}
-      else
-	gsi_next (&gsi);
-    }
-
-  /* Look for assignments to SSA names with constant RHS.  */
-  for (gimple_stmt_iterator gsi = gsi_start_bb (bb); !gsi_end_p (gsi); )
-    {
-      gimple *stmt = gsi_stmt (gsi);
-      tree lhs;
-
-      if (is_gimple_assign (stmt)
-	  && TREE_CODE_CLASS (gimple_assign_rhs_code (stmt)) == tcc_constant
-	  && (lhs = gimple_assign_lhs (stmt), TREE_CODE (lhs) == SSA_NAME)
-	  && !SSA_NAME_OCCURS_IN_ABNORMAL_PHI (lhs))
-	{
-	  replace_uses_by (lhs, gimple_assign_rhs1 (stmt));
-	  gsi_remove (&gsi, true);
-	  release_ssa_name (lhs);
-	}
-      else
-	gsi_next (&gsi);
-    }
-}
-
 /* Process loops from innermost to outer, stopping at the innermost
    loop we unrolled.  */
 
@@ -1512,10 +1469,14 @@ tree_unroll_loops_completely (bool may_increase_size, bool unroll_outer)
 	  EXECUTE_IF_SET_IN_BITMAP (fathers, 0, i, bi)
 	    {
 	      loop_p father = get_loop (cfun, i);
-	      basic_block *body = get_loop_body_in_dom_order (father);
-	      for (unsigned j = 0; j < father->num_nodes; j++)
-		propagate_constants_for_unrolling (body[j]);
-	      free (body);
+	      bitmap exit_bbs = BITMAP_ALLOC (NULL);
+	      loop_exit *exit = father->exits->next;
+	      while (exit->e)
+		{
+		  bitmap_set_bit (exit_bbs, exit->e->dest->index);
+		  exit = exit->next;
+		}
+	      do_rpo_vn (cfun, loop_preheader_edge (father), exit_bbs);
 	    }
 	  BITMAP_FREE (fathers);