graphite-isl-ast-to-gimple.c (translate_pending_phi_nodes): Verify both BBs…

graphite-isl-ast-to-gimple.c (translate_pending_phi_nodes): Verify both BBs contain loop PHI nodes before dispatching to copy_loop_phi_args.

2017-09-21  Richard Biener  <rguenther@suse.de>

	* graphite-isl-ast-to-gimple.c (translate_pending_phi_nodes):
	Verify both BBs contain loop PHI nodes before dispatching to
	copy_loop_phi_args.
	(graphite_regenerate_ast_isl): Do not recompute dominators,
	do not verify three times.  Restructure for clarity.
	* graphite-scop-detection.c (same_close_phi_node,
	remove_duplicate_close_phi, make_close_phi_nodes_unique,
	defined_in_loop_p, canonicalize_loop_closed_ssa,
	canonicalize_loop_closed_ssa_form): Simplify, remove excess
	checking and SSA rewrite, move to ...
	* graphite.c: ... here.  Include ssa.h and tree-ssa-loop-manip.h.
	(graphite_initialize): Do not pass in ctx, do not reset the
	SCEV cache, compute only dominators.
	(graphite_transform_loops): Allocate ISL ctx after
	graphite_initialize.  Call canonicalize_loop_closed_ssa_form.
	Maintain post-dominators only around build_scops.
	* sese.c (if_region_set_false_region): Make static.  Free
	and recompute dominators.
	(move_sese_in_condition): Assert we don't get called with
	post-dominators computed.
	* sese.h (if_region_set_false_region): Remove.

From-SVN: r253090

gcc/ChangeLog

+2017-09-22  Richard Biener  <rguenther@suse.de>
+
+	* graphite-isl-ast-to-gimple.c (translate_pending_phi_nodes):
+	Verify both BBs contain loop PHI nodes before dispatching to
+	copy_loop_phi_args.
+	(graphite_regenerate_ast_isl): Do not recompute dominators,
+	do not verify three times.  Restructure for clarity.
+	* graphite-scop-detection.c (same_close_phi_node,
+	remove_duplicate_close_phi, make_close_phi_nodes_unique,
+	defined_in_loop_p, canonicalize_loop_closed_ssa,
+	canonicalize_loop_closed_ssa_form): Simplify, remove excess
+	checking and SSA rewrite, move to ...
+	* graphite.c: ... here.  Include ssa.h and tree-ssa-loop-manip.h.
+	(graphite_initialize): Do not pass in ctx, do not reset the
+	SCEV cache, compute only dominators.
+	(graphite_transform_loops): Allocate ISL ctx after
+	graphite_initialize.  Call canonicalize_loop_closed_ssa_form.
+	Maintain post-dominators only around build_scops.
+	* sese.c (if_region_set_false_region): Make static.  Free
+	and recompute dominators.
+	(move_sese_in_condition): Assert we don't get called with
+	post-dominators computed.
+	* sese.h (if_region_set_false_region): Remove.
+
 2017-09-22  Sergey Shalnov  <sergey.shalnov@intel.com>
 
         * config/i386/sse.md ("mov<mode>_internal"): Use <sseinsnmode>

gcc/graphite-isl-ast-to-gimple.c

@@ -2759,7 +2759,8 @@ translate_pending_phi_nodes ()
 	}
 
       auto_vec <tree, 1> iv_map;
-      if (bb_contains_loop_phi_nodes (new_bb))
+      if (bb_contains_loop_phi_nodes (new_bb)
+	  && bb_contains_loop_phi_nodes (old_bb))
 	codegen_error = !copy_loop_phi_args (old_phi, ibp_old_bb, new_phi,
 					    ibp_new_bb, false);
       else if (bb_contains_loop_close_phi_nodes (new_bb))
@@ -2941,12 +2942,8 @@ graphite_regenerate_ast_isl (scop_p scop)
       print_isl_ast (dump_file, root_node);
     }
 
-  recompute_all_dominators ();
-  graphite_verify ();
-
   if_region = move_sese_in_condition (region);
   region->if_region = if_region;
-  recompute_all_dominators ();
 
   loop_p context_loop = region->region.entry->src->loop_father;
 
@@ -2960,45 +2957,28 @@ graphite_regenerate_ast_isl (scop_p scop)
   region->if_region->true_region->region.exit = single_succ_edge (bb);
 
   t.translate_isl_ast (context_loop, root_node, e, ip);
+  if (! t.codegen_error_p ())
+    t.translate_pending_phi_nodes ();
+  if (! t.codegen_error_p ())
+    {
+      sese_insert_phis_for_liveouts (region,
+				     if_region->region->region.exit->src,
+				     if_region->false_region->region.exit,
+				     if_region->true_region->region.exit);
+      if (dump_file)
+	fprintf (dump_file, "[codegen] isl AST to Gimple succeeded.\n");
+
+      mark_virtual_operands_for_renaming (cfun);
+      update_ssa (TODO_update_ssa);
+    }
+
   if (t.codegen_error_p ())
     {
       if (dump_file)
 	fprintf (dump_file, "codegen error: "
 		 "reverting back to the original code.\n");
       set_ifsese_condition (if_region, integer_zero_node);
-    }
-  else
-    {
-      t.translate_pending_phi_nodes ();
-      if (!t.codegen_error_p ())
-	{
-	  sese_insert_phis_for_liveouts (region,
-					 if_region->region->region.exit->src,
-					 if_region->false_region->region.exit,
-					 if_region->true_region->region.exit);
-	  mark_virtual_operands_for_renaming (cfun);
-	  update_ssa (TODO_update_ssa);
-
-
-	  graphite_verify ();
-	  scev_reset ();
-	  recompute_all_dominators ();
-	  graphite_verify ();
 
-	  if (dump_file)
-	    fprintf (dump_file, "[codegen] isl AST to Gimple succeeded.\n");
-	}
-      else
-	{
-	  if (dump_file)
-	    fprintf (dump_file, "[codegen] unsuccessful in translating"
-		     " pending phis, reverting back to the original code.\n");
-	  set_ifsese_condition (if_region, integer_zero_node);
-	}
-    }
-
-  if (t.codegen_error_p ())
-    {
       /* We registered new names, scrap that.  */
       if (need_ssa_update_p (cfun))
 	delete_update_ssa ();
@@ -3017,6 +2997,9 @@ graphite_regenerate_ast_isl (scop_p scop)
 	  delete_loop (loop);
     }
 
+  graphite_verify ();
+  scev_reset ();
+
   free (if_region->true_region);
   free (if_region->region);
   free (if_region);

gcc/graphite-scop-detection.c

@@ -268,187 +268,6 @@ trivially_empty_bb_p (basic_block bb)
   return true;
 }
 
-/* Returns true when P1 and P2 are close phis with the same
-   argument.  */
-
-static inline bool
-same_close_phi_node (gphi *p1, gphi *p2)
-{
-  return (types_compatible_p (TREE_TYPE (gimple_phi_result (p1)),
-			      TREE_TYPE (gimple_phi_result (p2)))
-	  && operand_equal_p (gimple_phi_arg_def (p1, 0),
-			      gimple_phi_arg_def (p2, 0), 0));
-}
-
-static void make_close_phi_nodes_unique (basic_block bb);
-
-/* Remove the close phi node at GSI and replace its rhs with the rhs
-   of PHI.  */
-
-static void
-remove_duplicate_close_phi (gphi *phi, gphi_iterator *gsi)
-{
-  gimple *use_stmt;
-  use_operand_p use_p;
-  imm_use_iterator imm_iter;
-  tree res = gimple_phi_result (phi);
-  tree def = gimple_phi_result (gsi->phi ());
-
-  gcc_assert (same_close_phi_node (phi, gsi->phi ()));
-
-  FOR_EACH_IMM_USE_STMT (use_stmt, imm_iter, def)
-    {
-      FOR_EACH_IMM_USE_ON_STMT (use_p, imm_iter)
-	SET_USE (use_p, res);
-
-      update_stmt (use_stmt);
-
-      /* It is possible that we just created a duplicate close-phi
-	 for an already-processed containing loop.  Check for this
-	 case and clean it up.  */
-      if (gimple_code (use_stmt) == GIMPLE_PHI
-	  && gimple_phi_num_args (use_stmt) == 1)
-	make_close_phi_nodes_unique (gimple_bb (use_stmt));
-    }
-
-  remove_phi_node (gsi, true);
-}
-
-/* Removes all the close phi duplicates from BB.  */
-
-static void
-make_close_phi_nodes_unique (basic_block bb)
-{
-  gphi_iterator psi;
-
-  for (psi = gsi_start_phis (bb); !gsi_end_p (psi); gsi_next (&psi))
-    {
-      gphi_iterator gsi = psi;
-      gphi *phi = psi.phi ();
-
-      /* At this point, PHI should be a close phi in normal form.  */
-      gcc_assert (gimple_phi_num_args (phi) == 1);
-
-      /* Iterate over the next phis and remove duplicates.  */
-      gsi_next (&gsi);
-      while (!gsi_end_p (gsi))
-	if (same_close_phi_node (phi, gsi.phi ()))
-	  remove_duplicate_close_phi (phi, &gsi);
-	else
-	  gsi_next (&gsi);
-    }
-}
-
-/* Return true when NAME is defined in LOOP.  */
-
-static bool
-defined_in_loop_p (tree name, loop_p loop)
-{
-  gcc_assert (TREE_CODE (name) == SSA_NAME);
-  return loop == loop_containing_stmt (SSA_NAME_DEF_STMT (name));
-}
-
-/* Transforms LOOP to the canonical loop closed SSA form.  */
-
-static void
-canonicalize_loop_closed_ssa (loop_p loop)
-{
-  edge e = single_exit (loop);
-  basic_block bb;
-
-  if (!e || (e->flags & EDGE_COMPLEX))
-    return;
-
-  bb = e->dest;
-
-  if (single_pred_p (bb))
-    {
-      e = split_block_after_labels (bb);
-      DEBUG_PRINT (dp << "Splitting bb_" << bb->index << ".\n");
-      make_close_phi_nodes_unique (e->src);
-    }
-  else
-    {
-      gphi_iterator psi;
-      basic_block close = split_edge (e);
-
-      e = single_succ_edge (close);
-      DEBUG_PRINT (dp << "Splitting edge (" << e->src->index << ","
-		      << e->dest->index << ")\n");
-
-      for (psi = gsi_start_phis (bb); !gsi_end_p (psi); gsi_next (&psi))
-	{
-	  gphi *phi = psi.phi ();
-	  unsigned i;
-
-	  for (i = 0; i < gimple_phi_num_args (phi); i++)
-	    if (gimple_phi_arg_edge (phi, i) == e)
-	      {
-		tree res, arg = gimple_phi_arg_def (phi, i);
-		use_operand_p use_p;
-		gphi *close_phi;
-
-		/* Only add close phi nodes for SSA_NAMEs defined in LOOP.  */
-		if (TREE_CODE (arg) != SSA_NAME
-		    || !defined_in_loop_p (arg, loop))
-		  continue;
-
-		close_phi = create_phi_node (NULL_TREE, close);
-		res = create_new_def_for (arg, close_phi,
-					  gimple_phi_result_ptr (close_phi));
-		add_phi_arg (close_phi, arg,
-			     gimple_phi_arg_edge (close_phi, 0),
-			     UNKNOWN_LOCATION);
-		use_p = gimple_phi_arg_imm_use_ptr (phi, i);
-		replace_exp (use_p, res);
-		update_stmt (phi);
-	      }
-	}
-
-      make_close_phi_nodes_unique (close);
-    }
-
-  /* The code above does not properly handle changes in the post dominance
-     information (yet).  */
-  recompute_all_dominators ();
-}
-
-/* Converts the current loop closed SSA form to a canonical form
-   expected by the Graphite code generation.
-
-   The loop closed SSA form has the following invariant: a variable
-   defined in a loop that is used outside the loop appears only in the
-   phi nodes in the destination of the loop exit.  These phi nodes are
-   called close phi nodes.
-
-   The canonical loop closed SSA form contains the extra invariants:
-
-   - when the loop contains only one exit, the close phi nodes contain
-   only one argument.  That implies that the basic block that contains
-   the close phi nodes has only one predecessor, that is a basic block
-   in the loop.
-
-   - the basic block containing the close phi nodes does not contain
-   other statements.
-
-   - there exist only one phi node per definition in the loop.
-*/
-
-static void
-canonicalize_loop_closed_ssa_form (void)
-{
-  checking_verify_loop_closed_ssa (true);
-
-  loop_p loop;
-  FOR_EACH_LOOP (loop, 0)
-    canonicalize_loop_closed_ssa (loop);
-
-  rewrite_into_loop_closed_ssa (NULL, TODO_update_ssa);
-  update_ssa (TODO_update_ssa);
-
-  checking_verify_loop_closed_ssa (true);
-}
-
 /* Can all ivs be represented by a signed integer?
    As isl might generate negative values in its expressions, signed loop ivs
    are required in the backend.  */
@@ -2038,8 +1857,6 @@ build_scops (vec<scop_p> *scops)
   if (dump_file)
     dp.set_dump_file (dump_file);
 
-  canonicalize_loop_closed_ssa_form ();
-
   /* ???  We walk the loop tree assuming loop->next is ordered.
      This is not so but we'd be free to order it here.  */
   scop_detection sb;

gcc/graphite.c

@@ -43,6 +43,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "cfghooks.h"
 #include "tree.h"
 #include "gimple.h"
+#include "ssa.h"
 #include "fold-const.h"
 #include "gimple-iterator.h"
 #include "tree-cfg.h"
@@ -53,6 +54,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "tree-parloops.h"
 #include "tree-cfgcleanup.h"
 #include "tree-vectorizer.h"
+#include "tree-ssa-loop-manip.h"
 #include "graphite.h"
 
 /* Print global statistics to FILE.  */
@@ -213,7 +215,7 @@ print_graphite_statistics (FILE* file, vec<scop_p> scops)
 /* Initialize graphite: when there are no loops returns false.  */
 
 static bool
-graphite_initialize (isl_ctx *ctx)
+graphite_initialize (void)
 {
   int min_loops = PARAM_VALUE (PARAM_GRAPHITE_MIN_LOOPS_PER_FUNCTION);
   int max_bbs = PARAM_VALUE (PARAM_GRAPHITE_MAX_BBS_PER_FUNCTION);
@@ -240,12 +242,10 @@ graphite_initialize (isl_ctx *ctx)
 	  print_global_statistics (dump_file);
 	}
 
-      isl_ctx_free (ctx);
       return false;
     }
 
-  scev_reset ();
-  recompute_all_dominators ();
+  calculate_dominance_info (CDI_DOMINATORS);
   initialize_original_copy_tables ();
 
   if (dump_file && dump_flags)
@@ -263,7 +263,6 @@ graphite_initialize (isl_ctx *ctx)
 static void
 graphite_finalize (bool need_cfg_cleanup_p)
 {
-  free_dominance_info (CDI_POST_DOMINATORS);
   if (need_cfg_cleanup_p)
     {
       free_dominance_info (CDI_DOMINATORS);
@@ -294,6 +293,162 @@ free_scops (vec<scop_p> scops)
   scops.release ();
 }
 
+/* Returns true when P1 and P2 are close phis with the same
+   argument.  */
+
+static inline bool
+same_close_phi_node (gphi *p1, gphi *p2)
+{
+  return (types_compatible_p (TREE_TYPE (gimple_phi_result (p1)),
+			      TREE_TYPE (gimple_phi_result (p2)))
+	  && operand_equal_p (gimple_phi_arg_def (p1, 0),
+			      gimple_phi_arg_def (p2, 0), 0));
+}
+
+static void make_close_phi_nodes_unique (basic_block bb);
+
+/* Remove the close phi node at GSI and replace its rhs with the rhs
+   of PHI.  */
+
+static void
+remove_duplicate_close_phi (gphi *phi, gphi_iterator *gsi)
+{
+  gimple *use_stmt;
+  use_operand_p use_p;
+  imm_use_iterator imm_iter;
+  tree res = gimple_phi_result (phi);
+  tree def = gimple_phi_result (gsi->phi ());
+
+  gcc_assert (same_close_phi_node (phi, gsi->phi ()));
+
+  FOR_EACH_IMM_USE_STMT (use_stmt, imm_iter, def)
+    {
+      FOR_EACH_IMM_USE_ON_STMT (use_p, imm_iter)
+	SET_USE (use_p, res);
+
+      update_stmt (use_stmt);
+
+      /* It is possible that we just created a duplicate close-phi
+	 for an already-processed containing loop.  Check for this
+	 case and clean it up.  */
+      if (gimple_code (use_stmt) == GIMPLE_PHI
+	  && gimple_phi_num_args (use_stmt) == 1)
+	make_close_phi_nodes_unique (gimple_bb (use_stmt));
+    }
+
+  remove_phi_node (gsi, true);
+}
+
+/* Removes all the close phi duplicates from BB.  */
+
+static void
+make_close_phi_nodes_unique (basic_block bb)
+{
+  gphi_iterator psi;
+
+  for (psi = gsi_start_phis (bb); !gsi_end_p (psi); gsi_next (&psi))
+    {
+      gphi_iterator gsi = psi;
+      gphi *phi = psi.phi ();
+
+      /* At this point, PHI should be a close phi in normal form.  */
+      gcc_assert (gimple_phi_num_args (phi) == 1);
+
+      /* Iterate over the next phis and remove duplicates.  */
+      gsi_next (&gsi);
+      while (!gsi_end_p (gsi))
+	if (same_close_phi_node (phi, gsi.phi ()))
+	  remove_duplicate_close_phi (phi, &gsi);
+	else
+	  gsi_next (&gsi);
+    }
+}
+
+/* Return true when NAME is defined in LOOP.  */
+
+static bool
+defined_in_loop_p (tree name, loop_p loop)
+{
+  gcc_assert (TREE_CODE (name) == SSA_NAME);
+  return loop == loop_containing_stmt (SSA_NAME_DEF_STMT (name));
+}
+
+/* Transforms LOOP to the canonical loop closed SSA form.  */
+
+static void
+canonicalize_loop_closed_ssa (loop_p loop)
+{
+  edge e = single_exit (loop);
+  basic_block bb;
+
+  if (!e || (e->flags & EDGE_COMPLEX))
+    return;
+
+  bb = e->dest;
+
+  if (single_pred_p (bb))
+    {
+      e = split_block_after_labels (bb);
+      make_close_phi_nodes_unique (e->src);
+    }
+  else
+    {
+      gphi_iterator psi;
+      basic_block close = split_edge (e);
+      e = single_succ_edge (close);
+      for (psi = gsi_start_phis (bb); !gsi_end_p (psi); gsi_next (&psi))
+	{
+	  gphi *phi = psi.phi ();
+	  use_operand_p use_p = PHI_ARG_DEF_PTR_FROM_EDGE (phi, e);
+	  tree arg = USE_FROM_PTR (use_p);
+
+	  /* Only add close phi nodes for SSA_NAMEs defined in LOOP.  */
+	  if (TREE_CODE (arg) != SSA_NAME
+	      || !defined_in_loop_p (arg, loop))
+	    continue;
+
+	  tree res = copy_ssa_name (arg);
+	  gphi *close_phi = create_phi_node (res, close);
+	  add_phi_arg (close_phi, arg, gimple_phi_arg_edge (close_phi, 0),
+		       UNKNOWN_LOCATION);
+	  SET_USE (use_p, res);
+	}
+
+      make_close_phi_nodes_unique (close);
+    }
+}
+
+/* Converts the current loop closed SSA form to a canonical form
+   expected by the Graphite code generation.
+
+   The loop closed SSA form has the following invariant: a variable
+   defined in a loop that is used outside the loop appears only in the
+   phi nodes in the destination of the loop exit.  These phi nodes are
+   called close phi nodes.
+
+   The canonical loop closed SSA form contains the extra invariants:
+
+   - when the loop contains only one exit, the close phi nodes contain
+   only one argument.  That implies that the basic block that contains
+   the close phi nodes has only one predecessor, that is a basic block
+   in the loop.
+
+   - the basic block containing the close phi nodes does not contain
+   other statements.
+
+   - there exist only one phi node per definition in the loop.
+*/
+
+static void
+canonicalize_loop_closed_ssa_form (void)
+{
+  loop_p loop;
+  FOR_EACH_LOOP (loop, 0)
+    canonicalize_loop_closed_ssa (loop);
+
+  checking_verify_loop_closed_ssa (true);
+}
+
 isl_ctx *the_isl_ctx;
 
 /* Perform a set of linear transforms on the loops of the current
@@ -313,13 +468,18 @@ graphite_transform_loops (void)
   if (parallelized_function_p (cfun->decl))
     return;
 
-  ctx = isl_ctx_alloc ();
-  isl_options_set_on_error (ctx, ISL_ON_ERROR_ABORT);
-  if (!graphite_initialize (ctx))
+  if (!graphite_initialize ())
     return;
 
+  ctx = isl_ctx_alloc ();
+  isl_options_set_on_error (ctx, ISL_ON_ERROR_ABORT);
   the_isl_ctx = ctx;
+
+  canonicalize_loop_closed_ssa_form ();
+
+  calculate_dominance_info (CDI_POST_DOMINATORS);
   build_scops (&scops);
+  free_dominance_info (CDI_POST_DOMINATORS);
 
   if (dump_file && (dump_flags & TDF_DETAILS))
     {

gcc/sese.c

@@ -335,9 +335,11 @@ get_false_edge_from_guard_bb (basic_block bb)
 
 /* Sets the false region of an IF_REGION to REGION.  */
 
-void
+static void
 if_region_set_false_region (ifsese if_region, sese_info_p region)
 {
+  free_dominance_info (CDI_DOMINATORS);
+
   basic_block condition = if_region_get_condition_block (if_region);
   edge false_edge = get_false_edge_from_guard_bb (condition);
   basic_block dummy = false_edge->dest;
@@ -348,6 +350,8 @@ if_region_set_false_region (ifsese if_region, sese_info_p region)
   hashval_t hash = htab_hash_pointer (exit_region);
   loop_exit **slot
     = current_loops->exits->find_slot_with_hash (exit_region, hash, NO_INSERT);
+  bool latch_p
+    = exit_region->dest->loop_father->latch == exit_region->src;
 
   entry_region->flags = false_edge->flags;
   false_edge->flags = exit_region->flags;
@@ -359,7 +363,6 @@ if_region_set_false_region (ifsese if_region, sese_info_p region)
   delete_basic_block (dummy);
 
   exit_region->flags = EDGE_FALLTHRU;
-  recompute_all_dominators ();
 
   region->region.exit = false_edge;
 
@@ -381,6 +384,10 @@ if_region_set_false_region (ifsese if_region, sese_info_p region)
       *slot = loop_exit;
       false_edge->src->loop_father->exits->next = loop_exit;
     }
+  if (latch_p)
+    exit_region->dest->loop_father->latch = before_region;
+
+  calculate_dominance_info (CDI_DOMINATORS);
 }
 
 /* Creates an IFSESE with CONDITION on edge ENTRY.  */
@@ -429,6 +436,7 @@ create_if_region_on_edge (edge entry, tree condition)
 ifsese
 move_sese_in_condition (sese_info_p region)
 {
+  gcc_assert (! dom_info_available_p (cfun, CDI_POST_DOMINATORS));
   basic_block pred_block = split_edge (region->region.entry);
   ifsese if_region;
 

gcc/sese.h

@@ -233,7 +233,6 @@ typedef struct ifsese_s {
   sese_info_p false_region;
 } *ifsese;
 
-extern void if_region_set_false_region (ifsese, sese_info_p);
 extern ifsese move_sese_in_condition (sese_info_p);
 extern void set_ifsese_condition (ifsese, tree);
 extern edge get_true_edge_from_guard_bb (basic_block);