1/* Miscellaneous SSA utility functions.
2   Copyright (C) 2001-2020 Free Software Foundation, Inc.
3
4This file is part of GCC.
5
6GCC is free software; you can redistribute it and/or modify
7it under the terms of the GNU General Public License as published by
8the Free Software Foundation; either version 3, or (at your option)
9any later version.
10
11GCC is distributed in the hope that it will be useful,
12but WITHOUT ANY WARRANTY; without even the implied warranty of
13MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14GNU General Public License for more details.
15
16You should have received a copy of the GNU General Public License
17along with GCC; see the file COPYING3.  If not see
18<http://www.gnu.org/licenses/>.  */
19
20#include "config.h"
21#include "system.h"
22#include "coretypes.h"
23#include "backend.h"
24#include "tree.h"
25#include "gimple.h"
26#include "cfghooks.h"
27#include "tree-pass.h"
28#include "ssa.h"
29#include "gimple-pretty-print.h"
30#include "diagnostic-core.h"
31#include "fold-const.h"
32#include "stor-layout.h"
33#include "gimple-fold.h"
34#include "gimplify.h"
35#include "gimple-iterator.h"
36#include "gimple-walk.h"
37#include "tree-ssa-loop-manip.h"
38#include "tree-into-ssa.h"
39#include "tree-ssa.h"
40#include "cfgloop.h"
41#include "cfgexpand.h"
42#include "tree-cfg.h"
43#include "tree-dfa.h"
44#include "stringpool.h"
45#include "attribs.h"
46#include "asan.h"
47
48/* Pointer map of variable mappings, keyed by edge.  */
49static hash_map<edge, auto_vec<edge_var_map> > *edge_var_maps;
50
51
52/* Add a mapping with PHI RESULT and PHI DEF associated with edge E.  */
53
54void
55redirect_edge_var_map_add (edge e, tree result, tree def, location_t locus)
56{
57  edge_var_map new_node;
58
59  if (edge_var_maps == NULL)
60    edge_var_maps = new hash_map<edge, auto_vec<edge_var_map> >;
61
62  auto_vec<edge_var_map> &slot = edge_var_maps->get_or_insert (e);
63  new_node.def = def;
64  new_node.result = result;
65  new_node.locus = locus;
66
67  slot.safe_push (new_node);
68}
69
70
71/* Clear the var mappings in edge E.  */
72
73void
74redirect_edge_var_map_clear (edge e)
75{
76  if (!edge_var_maps)
77    return;
78
79  auto_vec<edge_var_map> *head = edge_var_maps->get (e);
80
81  if (head)
82    head->release ();
83}
84
85
86/* Duplicate the redirected var mappings in OLDE in NEWE.
87
88   This assumes a hash_map can have multiple edges mapping to the same
89   var_map (many to one mapping), since we don't remove the previous mappings.
90   */
91
92void
93redirect_edge_var_map_dup (edge newe, edge olde)
94{
95  if (!edge_var_maps)
96    return;
97
98  auto_vec<edge_var_map> *new_head = &edge_var_maps->get_or_insert (newe);
99  auto_vec<edge_var_map> *old_head = edge_var_maps->get (olde);
100  if (!old_head)
101    return;
102
103  new_head->safe_splice (*old_head);
104}
105
106
107/* Return the variable mappings for a given edge.  If there is none, return
108   NULL.  */
109
110vec<edge_var_map> *
111redirect_edge_var_map_vector (edge e)
112{
113  /* Hey, what kind of idiot would... you'd be surprised.  */
114  if (!edge_var_maps)
115    return NULL;
116
117  auto_vec<edge_var_map> *slot = edge_var_maps->get (e);
118  if (!slot)
119    return NULL;
120
121  return slot;
122}
123
124/* Clear the edge variable mappings.  */
125
126void
127redirect_edge_var_map_empty (void)
128{
129  if (edge_var_maps)
130    edge_var_maps->empty ();
131}
132
133
134/* Remove the corresponding arguments from the PHI nodes in E's
135   destination block and redirect it to DEST.  Return redirected edge.
136   The list of removed arguments is stored in a vector accessed
137   through edge_var_maps.  */
138
139edge
140ssa_redirect_edge (edge e, basic_block dest)
141{
142  gphi_iterator gsi;
143  gphi *phi;
144
145  redirect_edge_var_map_clear (e);
146
147  /* Remove the appropriate PHI arguments in E's destination block.
148     If we are redirecting a copied edge the destination has not
149     got PHI argument space reserved nor an interesting argument.  */
150  if (! (e->dest->flags & BB_DUPLICATED))
151    for (gsi = gsi_start_phis (e->dest); !gsi_end_p (gsi); gsi_next (&gsi))
152      {
153	tree def;
154	location_t locus;
155
156	phi = gsi.phi ();
157	def = gimple_phi_arg_def (phi, e->dest_idx);
158	locus = gimple_phi_arg_location (phi, e->dest_idx);
159
160	if (def == NULL_TREE)
161	  continue;
162
163	redirect_edge_var_map_add (e, gimple_phi_result (phi), def, locus);
164      }
165
166  e = redirect_edge_succ_nodup (e, dest);
167
168  return e;
169}
170
171
172/* Add PHI arguments queued in PENDING_STMT list on edge E to edge
173   E->dest.  */
174
175void
176flush_pending_stmts (edge e)
177{
178  gphi *phi;
179  edge_var_map *vm;
180  int i;
181  gphi_iterator gsi;
182
183  vec<edge_var_map> *v = redirect_edge_var_map_vector (e);
184  if (!v)
185    return;
186
187  for (gsi = gsi_start_phis (e->dest), i = 0;
188       !gsi_end_p (gsi) && v->iterate (i, &vm);
189       gsi_next (&gsi), i++)
190    {
191      tree def;
192
193      phi = gsi.phi ();
194      def = redirect_edge_var_map_def (vm);
195      add_phi_arg (phi, def, e, redirect_edge_var_map_location (vm));
196    }
197
198  redirect_edge_var_map_clear (e);
199}
200
201/* Replace the LHS of STMT, an assignment, either a GIMPLE_ASSIGN or a
202   GIMPLE_CALL, with NLHS, in preparation for modifying the RHS to an
203   expression with a different value.
204
205   This will update any annotations (say debug bind stmts) referring
206   to the original LHS, so that they use the RHS instead.  This is
207   done even if NLHS and LHS are the same, for it is understood that
208   the RHS will be modified afterwards, and NLHS will not be assigned
209   an equivalent value.
210
211   Adjusting any non-annotation uses of the LHS, if needed, is a
212   responsibility of the caller.
213
214   The effect of this call should be pretty much the same as that of
215   inserting a copy of STMT before STMT, and then removing the
216   original stmt, at which time gsi_remove() would have update
217   annotations, but using this function saves all the inserting,
218   copying and removing.  */
219
220void
221gimple_replace_ssa_lhs (gimple *stmt, tree nlhs)
222{
223  if (MAY_HAVE_DEBUG_BIND_STMTS)
224    {
225      tree lhs = gimple_get_lhs (stmt);
226
227      gcc_assert (SSA_NAME_DEF_STMT (lhs) == stmt);
228
229      insert_debug_temp_for_var_def (NULL, lhs);
230    }
231
232  gimple_set_lhs (stmt, nlhs);
233}
234
235
236/* Given a tree for an expression for which we might want to emit
237   locations or values in debug information (generally a variable, but
238   we might deal with other kinds of trees in the future), return the
239   tree that should be used as the variable of a DEBUG_BIND STMT or
240   VAR_LOCATION INSN or NOTE.  Return NULL if VAR is not to be tracked.  */
241
242tree
243target_for_debug_bind (tree var)
244{
245  if (!MAY_HAVE_DEBUG_BIND_STMTS)
246    return NULL_TREE;
247
248  if (TREE_CODE (var) == SSA_NAME)
249    {
250      var = SSA_NAME_VAR (var);
251      if (var == NULL_TREE)
252	return NULL_TREE;
253    }
254
255  if ((!VAR_P (var) || VAR_DECL_IS_VIRTUAL_OPERAND (var))
256      && TREE_CODE (var) != PARM_DECL)
257    return NULL_TREE;
258
259  if (DECL_HAS_VALUE_EXPR_P (var))
260    return target_for_debug_bind (DECL_VALUE_EXPR (var));
261
262  if (DECL_IGNORED_P (var))
263    return NULL_TREE;
264
265  /* var-tracking only tracks registers.  */
266  if (!is_gimple_reg_type (TREE_TYPE (var)))
267    return NULL_TREE;
268
269  return var;
270}
271
272/* Called via walk_tree, look for SSA_NAMEs that have already been
273   released.  */
274
275static tree
276find_released_ssa_name (tree *tp, int *walk_subtrees, void *data_)
277{
278  struct walk_stmt_info *wi = (struct walk_stmt_info *) data_;
279
280  if (wi && wi->is_lhs)
281    return NULL_TREE;
282
283  if (TREE_CODE (*tp) == SSA_NAME)
284    {
285      if (SSA_NAME_IN_FREE_LIST (*tp))
286	return *tp;
287
288      *walk_subtrees = 0;
289    }
290  else if (IS_TYPE_OR_DECL_P (*tp))
291    *walk_subtrees = 0;
292
293  return NULL_TREE;
294}
295
296/* Insert a DEBUG BIND stmt before the DEF of VAR if VAR is referenced
297   by other DEBUG stmts, and replace uses of the DEF with the
298   newly-created debug temp.  */
299
300void
301insert_debug_temp_for_var_def (gimple_stmt_iterator *gsi, tree var)
302{
303  imm_use_iterator imm_iter;
304  use_operand_p use_p;
305  gimple *stmt;
306  gimple *def_stmt = NULL;
307  int usecount = 0;
308  tree value = NULL;
309
310  if (!MAY_HAVE_DEBUG_BIND_STMTS)
311    return;
312
313  /* If this name has already been registered for replacement, do nothing
314     as anything that uses this name isn't in SSA form.  */
315  if (name_registered_for_update_p (var))
316    return;
317
318  /* Check whether there are debug stmts that reference this variable and,
319     if there are, decide whether we should use a debug temp.  */
320  FOR_EACH_IMM_USE_FAST (use_p, imm_iter, var)
321    {
322      stmt = USE_STMT (use_p);
323
324      if (!gimple_debug_bind_p (stmt))
325	continue;
326
327      if (usecount++)
328	break;
329
330      if (gimple_debug_bind_get_value (stmt) != var)
331	{
332	  /* Count this as an additional use, so as to make sure we
333	     use a temp unless VAR's definition has a SINGLE_RHS that
334	     can be shared.  */
335	  usecount++;
336	  break;
337	}
338    }
339
340  if (!usecount)
341    return;
342
343  if (gsi)
344    def_stmt = gsi_stmt (*gsi);
345  else
346    def_stmt = SSA_NAME_DEF_STMT (var);
347
348  /* If we didn't get an insertion point, and the stmt has already
349     been removed, we won't be able to insert the debug bind stmt, so
350     we'll have to drop debug information.  */
351  if (gimple_code (def_stmt) == GIMPLE_PHI)
352    {
353      value = degenerate_phi_result (as_a <gphi *> (def_stmt));
354      if (value && walk_tree (&value, find_released_ssa_name, NULL, NULL))
355	value = NULL;
356      /* error_mark_node is what fixup_noreturn_call changes PHI arguments
357	 to.  */
358      else if (value == error_mark_node)
359	value = NULL;
360    }
361  else if (gimple_clobber_p (def_stmt))
362    /* We can end up here when rewriting a decl into SSA and coming
363       along a clobber for the original decl.  Turn that into
364       # DEBUG decl => NULL  */
365    value = NULL;
366  else if (is_gimple_assign (def_stmt))
367    {
368      bool no_value = false;
369
370      if (!dom_info_available_p (CDI_DOMINATORS))
371	{
372	  struct walk_stmt_info wi;
373
374	  memset (&wi, 0, sizeof (wi));
375
376	  /* When removing blocks without following reverse dominance
377	     order, we may sometimes encounter SSA_NAMEs that have
378	     already been released, referenced in other SSA_DEFs that
379	     we're about to release.  Consider:
380
381	     <bb X>:
382	     v_1 = foo;
383
384	     <bb Y>:
385	     w_2 = v_1 + bar;
386	     # DEBUG w => w_2
387
388	     If we deleted BB X first, propagating the value of w_2
389	     won't do us any good.  It's too late to recover their
390	     original definition of v_1: when it was deleted, it was
391	     only referenced in other DEFs, it couldn't possibly know
392	     it should have been retained, and propagating every
393	     single DEF just in case it might have to be propagated
394	     into a DEBUG STMT would probably be too wasteful.
395
396	     When dominator information is not readily available, we
397	     check for and accept some loss of debug information.  But
398	     if it is available, there's no excuse for us to remove
399	     blocks in the wrong order, so we don't even check for
400	     dead SSA NAMEs.  SSA verification shall catch any
401	     errors.  */
402	  if ((!gsi && !gimple_bb (def_stmt))
403	      || walk_gimple_op (def_stmt, find_released_ssa_name, &wi))
404	    no_value = true;
405	}
406
407      if (!no_value)
408	value = gimple_assign_rhs_to_tree (def_stmt);
409    }
410
411  if (value)
412    {
413      /* If there's a single use of VAR, and VAR is the entire debug
414	 expression (usecount would have been incremented again
415	 otherwise), and the definition involves only constants and
416	 SSA names, then we can propagate VALUE into this single use,
417	 avoiding the temp.
418
419	 We can also avoid using a temp if VALUE can be shared and
420	 propagated into all uses, without generating expressions that
421	 wouldn't be valid gimple RHSs.
422
423	 Other cases that would require unsharing or non-gimple RHSs
424	 are deferred to a debug temp, although we could avoid temps
425	 at the expense of duplication of expressions.  */
426
427      if (CONSTANT_CLASS_P (value)
428	  || gimple_code (def_stmt) == GIMPLE_PHI
429	  || (usecount == 1
430	      && (!gimple_assign_single_p (def_stmt)
431		  || is_gimple_min_invariant (value)))
432	  || is_gimple_reg (value))
433	;
434      else
435	{
436	  gdebug *def_temp;
437	  tree vexpr = make_node (DEBUG_EXPR_DECL);
438
439	  def_temp = gimple_build_debug_bind (vexpr,
440					      unshare_expr (value),
441					      def_stmt);
442
443	  DECL_ARTIFICIAL (vexpr) = 1;
444	  TREE_TYPE (vexpr) = TREE_TYPE (value);
445	  if (DECL_P (value))
446	    SET_DECL_MODE (vexpr, DECL_MODE (value));
447	  else
448	    SET_DECL_MODE (vexpr, TYPE_MODE (TREE_TYPE (value)));
449
450	  if (gsi)
451	    gsi_insert_before (gsi, def_temp, GSI_SAME_STMT);
452	  else
453	    {
454	      gimple_stmt_iterator ngsi = gsi_for_stmt (def_stmt);
455	      gsi_insert_before (&ngsi, def_temp, GSI_SAME_STMT);
456	    }
457
458	  value = vexpr;
459	}
460    }
461
462  FOR_EACH_IMM_USE_STMT (stmt, imm_iter, var)
463    {
464      if (!gimple_debug_bind_p (stmt))
465	continue;
466
467      if (value)
468	{
469	  FOR_EACH_IMM_USE_ON_STMT (use_p, imm_iter)
470	    /* unshare_expr is not needed here.  vexpr is either a
471	       SINGLE_RHS, that can be safely shared, some other RHS
472	       that was unshared when we found it had a single debug
473	       use, or a DEBUG_EXPR_DECL, that can be safely
474	       shared.  */
475	    SET_USE (use_p, unshare_expr (value));
476	  /* If we didn't replace uses with a debug decl fold the
477	     resulting expression.  Otherwise we end up with invalid IL.  */
478	  if (TREE_CODE (value) != DEBUG_EXPR_DECL)
479	    {
480	      gimple_stmt_iterator gsi = gsi_for_stmt (stmt);
481	      fold_stmt_inplace (&gsi);
482	    }
483	}
484      else
485	gimple_debug_bind_reset_value (stmt);
486
487      update_stmt (stmt);
488    }
489}
490
491
492/* Insert a DEBUG BIND stmt before STMT for each DEF referenced by
493   other DEBUG stmts, and replace uses of the DEF with the
494   newly-created debug temp.  */
495
496void
497insert_debug_temps_for_defs (gimple_stmt_iterator *gsi)
498{
499  gimple *stmt;
500  ssa_op_iter op_iter;
501  def_operand_p def_p;
502
503  if (!MAY_HAVE_DEBUG_BIND_STMTS)
504    return;
505
506  stmt = gsi_stmt (*gsi);
507
508  FOR_EACH_PHI_OR_STMT_DEF (def_p, stmt, op_iter, SSA_OP_DEF)
509    {
510      tree var = DEF_FROM_PTR (def_p);
511
512      if (TREE_CODE (var) != SSA_NAME)
513	continue;
514
515      insert_debug_temp_for_var_def (gsi, var);
516    }
517}
518
519/* Reset all debug stmts that use SSA_NAME(s) defined in STMT.  */
520
521void
522reset_debug_uses (gimple *stmt)
523{
524  ssa_op_iter op_iter;
525  def_operand_p def_p;
526  imm_use_iterator imm_iter;
527  gimple *use_stmt;
528
529  if (!MAY_HAVE_DEBUG_BIND_STMTS)
530    return;
531
532  FOR_EACH_PHI_OR_STMT_DEF (def_p, stmt, op_iter, SSA_OP_DEF)
533    {
534      tree var = DEF_FROM_PTR (def_p);
535
536      if (TREE_CODE (var) != SSA_NAME)
537	continue;
538
539      FOR_EACH_IMM_USE_STMT (use_stmt, imm_iter, var)
540	{
541	  if (!gimple_debug_bind_p (use_stmt))
542	    continue;
543
544	  gimple_debug_bind_reset_value (use_stmt);
545	  update_stmt (use_stmt);
546	}
547    }
548}
549
550/* Delete SSA DEFs for SSA versions in the TOREMOVE bitmap, removing
551   dominated stmts before their dominators, so that release_ssa_defs
552   stands a chance of propagating DEFs into debug bind stmts.  */
553
554void
555release_defs_bitset (bitmap toremove)
556{
557  unsigned j;
558  bitmap_iterator bi;
559
560  /* Performing a topological sort is probably overkill, this will
561     most likely run in slightly superlinear time, rather than the
562     pathological quadratic worst case.
563     But iterate from max SSA name version to min one because
564     that mimics allocation order during code generation behavior best.
565     Use an array for this which we compact on-the-fly with a NULL
566     marker moving towards the end of the vector.  */
567  auto_vec<tree, 16> names;
568  names.reserve (bitmap_count_bits (toremove) + 1);
569  names.quick_push (NULL_TREE);
570  EXECUTE_IF_SET_IN_BITMAP (toremove, 0, j, bi)
571    names.quick_push (ssa_name (j));
572
573  bitmap_tree_view (toremove);
574  while (!bitmap_empty_p (toremove))
575    {
576      j = names.length () - 1;
577      for (unsigned i = names.length () - 1; names[i];)
578	{
579	  bool remove_now = true;
580	  tree var = names[i];
581	  gimple *stmt;
582	  imm_use_iterator uit;
583
584	  FOR_EACH_IMM_USE_STMT (stmt, uit, var)
585	    {
586	      ssa_op_iter dit;
587	      def_operand_p def_p;
588
589	      /* We can't propagate PHI nodes into debug stmts.  */
590	      if (gimple_code (stmt) == GIMPLE_PHI
591		  || is_gimple_debug (stmt))
592		continue;
593
594	      /* If we find another definition to remove that uses
595		 the one we're looking at, defer the removal of this
596		 one, so that it can be propagated into debug stmts
597		 after the other is.  */
598	      FOR_EACH_SSA_DEF_OPERAND (def_p, stmt, dit, SSA_OP_DEF)
599		{
600		  tree odef = DEF_FROM_PTR (def_p);
601
602		  if (bitmap_bit_p (toremove, SSA_NAME_VERSION (odef)))
603		    {
604		      remove_now = false;
605		      break;
606		    }
607		}
608
609	      if (!remove_now)
610		BREAK_FROM_IMM_USE_STMT (uit);
611	    }
612
613	  if (remove_now)
614	    {
615	      gimple *def = SSA_NAME_DEF_STMT (var);
616	      gimple_stmt_iterator gsi = gsi_for_stmt (def);
617
618	      if (gimple_code (def) == GIMPLE_PHI)
619		remove_phi_node (&gsi, true);
620	      else
621		{
622		  gsi_remove (&gsi, true);
623		  release_defs (def);
624		}
625	      bitmap_clear_bit (toremove, SSA_NAME_VERSION (var));
626	    }
627	  else
628	    --i;
629	  if (--j != i)
630	    names[i] = names[j];
631	}
632    }
633  bitmap_list_view (toremove);
634}
635
636/* Disable warnings about missing quoting in GCC diagnostics for
637   the verification errors.  Their format strings don't follow GCC
638   diagnostic conventions and the calls are ultimately followed by
639   one to internal_error.  */
640#if __GNUC__ >= 10
641#  pragma GCC diagnostic push
642#  pragma GCC diagnostic ignored "-Wformat-diag"
643#endif
644
645/* Verify virtual SSA form.  */
646
647bool
648verify_vssa (basic_block bb, tree current_vdef, sbitmap visited)
649{
650  bool err = false;
651
652  if (bitmap_bit_p (visited, bb->index))
653    return false;
654
655  bitmap_set_bit (visited, bb->index);
656
657  /* Pick up the single virtual PHI def.  */
658  gphi *phi = NULL;
659  for (gphi_iterator si = gsi_start_phis (bb); !gsi_end_p (si);
660       gsi_next (&si))
661    {
662      tree res = gimple_phi_result (si.phi ());
663      if (virtual_operand_p (res))
664	{
665	  if (phi)
666	    {
667	      error ("multiple virtual PHI nodes in BB %d", bb->index);
668	      print_gimple_stmt (stderr, phi, 0);
669	      print_gimple_stmt (stderr, si.phi (), 0);
670	      err = true;
671	    }
672	  else
673	    phi = si.phi ();
674	}
675    }
676  if (phi)
677    {
678      current_vdef = gimple_phi_result (phi);
679      if (TREE_CODE (current_vdef) != SSA_NAME)
680	{
681	  error ("virtual definition is not an SSA name");
682	  print_gimple_stmt (stderr, phi, 0);
683	  err = true;
684	}
685    }
686
687  /* Verify stmts.  */
688  for (gimple_stmt_iterator gsi = gsi_start_bb (bb); !gsi_end_p (gsi);
689       gsi_next (&gsi))
690    {
691      gimple *stmt = gsi_stmt (gsi);
692      tree vuse = gimple_vuse (stmt);
693      if (vuse)
694	{
695	  if (vuse != current_vdef)
696	    {
697	      error ("stmt with wrong VUSE");
698	      print_gimple_stmt (stderr, stmt, 0, TDF_VOPS);
699	      fprintf (stderr, "expected ");
700	      print_generic_expr (stderr, current_vdef);
701	      fprintf (stderr, "\n");
702	      err = true;
703	    }
704	  tree vdef = gimple_vdef (stmt);
705	  if (vdef)
706	    {
707	      current_vdef = vdef;
708	      if (TREE_CODE (current_vdef) != SSA_NAME)
709		{
710		  error ("virtual definition is not an SSA name");
711		  print_gimple_stmt (stderr, phi, 0);
712		  err = true;
713		}
714	    }
715	}
716    }
717
718  /* Verify destination PHI uses and recurse.  */
719  edge_iterator ei;
720  edge e;
721  FOR_EACH_EDGE (e, ei, bb->succs)
722    {
723      gphi *phi = get_virtual_phi (e->dest);
724      if (phi
725	  && PHI_ARG_DEF_FROM_EDGE (phi, e) != current_vdef)
726	{
727	  error ("PHI node with wrong VUSE on edge from BB %d",
728		 e->src->index);
729	  print_gimple_stmt (stderr, phi, 0, TDF_VOPS);
730	  fprintf (stderr, "expected ");
731	  print_generic_expr (stderr, current_vdef);
732	  fprintf (stderr, "\n");
733	  err = true;
734	}
735
736      /* Recurse.  */
737      err |= verify_vssa (e->dest, current_vdef, visited);
738    }
739
740  return err;
741}
742
743/* Return true if SSA_NAME is malformed and mark it visited.
744
745   IS_VIRTUAL is true if this SSA_NAME was found inside a virtual
746      operand.  */
747
748static bool
749verify_ssa_name (tree ssa_name, bool is_virtual)
750{
751  if (TREE_CODE (ssa_name) != SSA_NAME)
752    {
753      error ("expected an SSA_NAME object");
754      return true;
755    }
756
757  if (SSA_NAME_IN_FREE_LIST (ssa_name))
758    {
759      error ("found an SSA_NAME that had been released into the free pool");
760      return true;
761    }
762
763  if (SSA_NAME_VAR (ssa_name) != NULL_TREE
764      && TREE_TYPE (ssa_name) != TREE_TYPE (SSA_NAME_VAR (ssa_name)))
765    {
766      error ("type mismatch between an SSA_NAME and its symbol");
767      return true;
768    }
769
770  if (is_virtual && !virtual_operand_p (ssa_name))
771    {
772      error ("found a virtual definition for a GIMPLE register");
773      return true;
774    }
775
776  if (is_virtual && SSA_NAME_VAR (ssa_name) != gimple_vop (cfun))
777    {
778      error ("virtual SSA name for non-VOP decl");
779      return true;
780    }
781
782  if (!is_virtual && virtual_operand_p (ssa_name))
783    {
784      error ("found a real definition for a non-register");
785      return true;
786    }
787
788  if (SSA_NAME_IS_DEFAULT_DEF (ssa_name)
789      && !gimple_nop_p (SSA_NAME_DEF_STMT (ssa_name)))
790    {
791      error ("found a default name with a non-empty defining statement");
792      return true;
793    }
794
795  return false;
796}
797
798
799/* Return true if the definition of SSA_NAME at block BB is malformed.
800
801   STMT is the statement where SSA_NAME is created.
802
803   DEFINITION_BLOCK is an array of basic blocks indexed by SSA_NAME
804      version numbers.  If DEFINITION_BLOCK[SSA_NAME_VERSION] is set,
805      it means that the block in that array slot contains the
806      definition of SSA_NAME.
807
808   IS_VIRTUAL is true if SSA_NAME is created by a VDEF.  */
809
810static bool
811verify_def (basic_block bb, basic_block *definition_block, tree ssa_name,
812	    gimple *stmt, bool is_virtual)
813{
814  if (verify_ssa_name (ssa_name, is_virtual))
815    goto err;
816
817  if (SSA_NAME_VAR (ssa_name)
818      && TREE_CODE (SSA_NAME_VAR (ssa_name)) == RESULT_DECL
819      && DECL_BY_REFERENCE (SSA_NAME_VAR (ssa_name)))
820    {
821      error ("RESULT_DECL should be read only when DECL_BY_REFERENCE is set");
822      goto err;
823    }
824
825  if (definition_block[SSA_NAME_VERSION (ssa_name)])
826    {
827      error ("SSA_NAME created in two different blocks %i and %i",
828	     definition_block[SSA_NAME_VERSION (ssa_name)]->index, bb->index);
829      goto err;
830    }
831
832  definition_block[SSA_NAME_VERSION (ssa_name)] = bb;
833
834  if (SSA_NAME_DEF_STMT (ssa_name) != stmt)
835    {
836      error ("SSA_NAME_DEF_STMT is wrong");
837      fprintf (stderr, "Expected definition statement:\n");
838      print_gimple_stmt (stderr, SSA_NAME_DEF_STMT (ssa_name), 4, TDF_VOPS);
839      fprintf (stderr, "\nActual definition statement:\n");
840      print_gimple_stmt (stderr, stmt, 4, TDF_VOPS);
841      goto err;
842    }
843
844  return false;
845
846err:
847  fprintf (stderr, "while verifying SSA_NAME ");
848  print_generic_expr (stderr, ssa_name);
849  fprintf (stderr, " in statement\n");
850  print_gimple_stmt (stderr, stmt, 4, TDF_VOPS);
851
852  return true;
853}
854
855
856/* Return true if the use of SSA_NAME at statement STMT in block BB is
857   malformed.
858
859   DEF_BB is the block where SSA_NAME was found to be created.
860
861   IDOM contains immediate dominator information for the flowgraph.
862
863   CHECK_ABNORMAL is true if the caller wants to check whether this use
864      is flowing through an abnormal edge (only used when checking PHI
865      arguments).
866
867   If NAMES_DEFINED_IN_BB is not NULL, it contains a bitmap of ssa names
868     that are defined before STMT in basic block BB.  */
869
870static bool
871verify_use (basic_block bb, basic_block def_bb, use_operand_p use_p,
872	    gimple *stmt, bool check_abnormal, bitmap names_defined_in_bb)
873{
874  bool err = false;
875  tree ssa_name = USE_FROM_PTR (use_p);
876
877  if (!TREE_VISITED (ssa_name))
878    if (verify_imm_links (stderr, ssa_name))
879      err = true;
880
881  TREE_VISITED (ssa_name) = 1;
882
883  if (gimple_nop_p (SSA_NAME_DEF_STMT (ssa_name))
884      && SSA_NAME_IS_DEFAULT_DEF (ssa_name))
885    ; /* Default definitions have empty statements.  Nothing to do.  */
886  else if (!def_bb)
887    {
888      error ("missing definition");
889      err = true;
890    }
891  else if (bb != def_bb
892	   && !dominated_by_p (CDI_DOMINATORS, bb, def_bb))
893    {
894      error ("definition in block %i does not dominate use in block %i",
895	     def_bb->index, bb->index);
896      err = true;
897    }
898  else if (bb == def_bb
899	   && names_defined_in_bb != NULL
900	   && !bitmap_bit_p (names_defined_in_bb, SSA_NAME_VERSION (ssa_name)))
901    {
902      error ("definition in block %i follows the use", def_bb->index);
903      err = true;
904    }
905
906  if (check_abnormal
907      && !SSA_NAME_OCCURS_IN_ABNORMAL_PHI (ssa_name))
908    {
909      error ("SSA_NAME_OCCURS_IN_ABNORMAL_PHI should be set");
910      err = true;
911    }
912
913  /* Make sure the use is in an appropriate list by checking the previous
914     element to make sure it's the same.  */
915  if (use_p->prev == NULL)
916    {
917      error ("no immediate_use list");
918      err = true;
919    }
920  else
921    {
922      tree listvar;
923      if (use_p->prev->use == NULL)
924	listvar = use_p->prev->loc.ssa_name;
925      else
926	listvar = USE_FROM_PTR (use_p->prev);
927      if (listvar != ssa_name)
928        {
929	  error ("wrong immediate use list");
930	  err = true;
931	}
932    }
933
934  if (err)
935    {
936      fprintf (stderr, "for SSA_NAME: ");
937      print_generic_expr (stderr, ssa_name, TDF_VOPS);
938      fprintf (stderr, " in statement:\n");
939      print_gimple_stmt (stderr, stmt, 0, TDF_VOPS);
940    }
941
942  return err;
943}
944
945
946/* Return true if any of the arguments for PHI node PHI at block BB is
947   malformed.
948
949   DEFINITION_BLOCK is an array of basic blocks indexed by SSA_NAME
950      version numbers.  If DEFINITION_BLOCK[SSA_NAME_VERSION] is set,
951      it means that the block in that array slot contains the
952      definition of SSA_NAME.  */
953
954static bool
955verify_phi_args (gphi *phi, basic_block bb, basic_block *definition_block)
956{
957  edge e;
958  bool err = false;
959  size_t i, phi_num_args = gimple_phi_num_args (phi);
960
961  if (EDGE_COUNT (bb->preds) != phi_num_args)
962    {
963      error ("incoming edge count does not match number of PHI arguments");
964      err = true;
965      goto error;
966    }
967
968  for (i = 0; i < phi_num_args; i++)
969    {
970      use_operand_p op_p = gimple_phi_arg_imm_use_ptr (phi, i);
971      tree op = USE_FROM_PTR (op_p);
972
973      e = EDGE_PRED (bb, i);
974
975      if (op == NULL_TREE)
976	{
977	  error ("PHI argument is missing for edge %d->%d",
978	         e->src->index,
979		 e->dest->index);
980	  err = true;
981	  goto error;
982	}
983
984      if (TREE_CODE (op) != SSA_NAME && !is_gimple_min_invariant (op))
985	{
986	  error ("PHI argument is not SSA_NAME, or invariant");
987	  err = true;
988	}
989
990      if (TREE_CODE (op) == SSA_NAME)
991	{
992	  err = verify_ssa_name (op, virtual_operand_p (gimple_phi_result (phi)));
993	  err |= verify_use (e->src, definition_block[SSA_NAME_VERSION (op)],
994			     op_p, phi, e->flags & EDGE_ABNORMAL, NULL);
995	}
996
997      if (TREE_CODE (op) == ADDR_EXPR)
998	{
999	  tree base = TREE_OPERAND (op, 0);
1000	  while (handled_component_p (base))
1001	    base = TREE_OPERAND (base, 0);
1002	  if ((VAR_P (base)
1003	       || TREE_CODE (base) == PARM_DECL
1004	       || TREE_CODE (base) == RESULT_DECL)
1005	      && !TREE_ADDRESSABLE (base))
1006	    {
1007	      error ("address taken, but ADDRESSABLE bit not set");
1008	      err = true;
1009	    }
1010	}
1011
1012      if (e->dest != bb)
1013	{
1014	  error ("wrong edge %d->%d for PHI argument",
1015	         e->src->index, e->dest->index);
1016	  err = true;
1017	}
1018
1019      if (err)
1020	{
1021	  fprintf (stderr, "PHI argument\n");
1022	  print_generic_stmt (stderr, op, TDF_VOPS);
1023	  goto error;
1024	}
1025    }
1026
1027error:
1028  if (err)
1029    {
1030      fprintf (stderr, "for PHI node\n");
1031      print_gimple_stmt (stderr, phi, 0, TDF_VOPS|TDF_MEMSYMS);
1032    }
1033
1034
1035  return err;
1036}
1037
1038
1039/* Verify common invariants in the SSA web.
1040   TODO: verify the variable annotations.  */
1041
1042DEBUG_FUNCTION void
1043verify_ssa (bool check_modified_stmt, bool check_ssa_operands)
1044{
1045  basic_block bb;
1046  basic_block *definition_block = XCNEWVEC (basic_block, num_ssa_names);
1047  ssa_op_iter iter;
1048  tree op;
1049  enum dom_state orig_dom_state = dom_info_state (CDI_DOMINATORS);
1050  auto_bitmap names_defined_in_bb;
1051
1052  gcc_assert (!need_ssa_update_p (cfun));
1053
1054  timevar_push (TV_TREE_SSA_VERIFY);
1055
1056    {
1057      /* Keep track of SSA names present in the IL.  */
1058      size_t i;
1059      tree name;
1060      hash_map <void *, tree> ssa_info;
1061
1062      FOR_EACH_SSA_NAME (i, name, cfun)
1063	{
1064	  gimple *stmt;
1065	  TREE_VISITED (name) = 0;
1066
1067	  verify_ssa_name (name, virtual_operand_p (name));
1068
1069	  stmt = SSA_NAME_DEF_STMT (name);
1070	  if (!gimple_nop_p (stmt))
1071	    {
1072	      basic_block bb = gimple_bb (stmt);
1073	      if (verify_def (bb, definition_block,
1074			      name, stmt, virtual_operand_p (name)))
1075		goto err;
1076	    }
1077
1078	  void *info = NULL;
1079	  if (POINTER_TYPE_P (TREE_TYPE (name)))
1080	    info = SSA_NAME_PTR_INFO (name);
1081	  else if (INTEGRAL_TYPE_P (TREE_TYPE (name)))
1082	    info = SSA_NAME_RANGE_INFO (name);
1083	  if (info)
1084	    {
1085	      bool existed;
1086	      tree &val = ssa_info.get_or_insert (info, &existed);
1087	      if (existed)
1088		{
1089		  error ("shared SSA name info");
1090		  print_generic_expr (stderr, val);
1091		  fprintf (stderr, " and ");
1092		  print_generic_expr (stderr, name);
1093		  fprintf (stderr, "\n");
1094		  goto err;
1095		}
1096	      else
1097		val = name;
1098	    }
1099	}
1100    }
1101
1102  calculate_dominance_info (CDI_DOMINATORS);
1103
1104  /* Now verify all the uses and make sure they agree with the definitions
1105     found in the previous pass.  */
1106  FOR_EACH_BB_FN (bb, cfun)
1107    {
1108      edge e;
1109      edge_iterator ei;
1110
1111      /* Make sure that all edges have a clear 'aux' field.  */
1112      FOR_EACH_EDGE (e, ei, bb->preds)
1113	{
1114	  if (e->aux)
1115	    {
1116	      error ("AUX pointer initialized for edge %d->%d", e->src->index,
1117		      e->dest->index);
1118	      goto err;
1119	    }
1120	}
1121
1122      /* Verify the arguments for every PHI node in the block.  */
1123      for (gphi_iterator gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
1124	{
1125	  gphi *phi = gsi.phi ();
1126	  if (verify_phi_args (phi, bb, definition_block))
1127	    goto err;
1128
1129	  bitmap_set_bit (names_defined_in_bb,
1130			  SSA_NAME_VERSION (gimple_phi_result (phi)));
1131	}
1132
1133      /* Now verify all the uses and vuses in every statement of the block.  */
1134      for (gimple_stmt_iterator gsi = gsi_start_bb (bb); !gsi_end_p (gsi);
1135	   gsi_next (&gsi))
1136	{
1137	  gimple *stmt = gsi_stmt (gsi);
1138	  use_operand_p use_p;
1139
1140	  if (check_modified_stmt && gimple_modified_p (stmt))
1141	    {
1142	      error ("stmt (%p) marked modified after optimization pass: ",
1143		     (void *)stmt);
1144	      print_gimple_stmt (stderr, stmt, 0, TDF_VOPS);
1145	      goto err;
1146	    }
1147
1148	  if (check_ssa_operands && verify_ssa_operands (cfun, stmt))
1149	    {
1150	      print_gimple_stmt (stderr, stmt, 0, TDF_VOPS);
1151	      goto err;
1152	    }
1153
1154	  if (gimple_debug_bind_p (stmt)
1155	      && !gimple_debug_bind_has_value_p (stmt))
1156	    continue;
1157
1158	  FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter, SSA_OP_USE|SSA_OP_VUSE)
1159	    {
1160	      op = USE_FROM_PTR (use_p);
1161	      if (verify_use (bb, definition_block[SSA_NAME_VERSION (op)],
1162			      use_p, stmt, false, names_defined_in_bb))
1163		goto err;
1164	    }
1165
1166	  FOR_EACH_SSA_TREE_OPERAND (op, stmt, iter, SSA_OP_ALL_DEFS)
1167	    {
1168	      if (SSA_NAME_DEF_STMT (op) != stmt)
1169		{
1170		  error ("SSA_NAME_DEF_STMT is wrong");
1171		  fprintf (stderr, "Expected definition statement:\n");
1172		  print_gimple_stmt (stderr, stmt, 4, TDF_VOPS);
1173		  fprintf (stderr, "\nActual definition statement:\n");
1174		  print_gimple_stmt (stderr, SSA_NAME_DEF_STMT (op),
1175				     4, TDF_VOPS);
1176		  goto err;
1177		}
1178	      bitmap_set_bit (names_defined_in_bb, SSA_NAME_VERSION (op));
1179	    }
1180	}
1181
1182      bitmap_clear (names_defined_in_bb);
1183    }
1184
1185  free (definition_block);
1186
1187  if (gimple_vop (cfun)
1188      && ssa_default_def (cfun, gimple_vop (cfun)))
1189    {
1190      auto_sbitmap visited (last_basic_block_for_fn (cfun) + 1);
1191      bitmap_clear (visited);
1192      if (verify_vssa (ENTRY_BLOCK_PTR_FOR_FN (cfun),
1193		       ssa_default_def (cfun, gimple_vop (cfun)), visited))
1194	goto err;
1195    }
1196
1197  /* Restore the dominance information to its prior known state, so
1198     that we do not perturb the compiler's subsequent behavior.  */
1199  if (orig_dom_state == DOM_NONE)
1200    free_dominance_info (CDI_DOMINATORS);
1201  else
1202    set_dom_info_availability (CDI_DOMINATORS, orig_dom_state);
1203
1204  timevar_pop (TV_TREE_SSA_VERIFY);
1205  return;
1206
1207err:
1208  internal_error ("verify_ssa failed");
1209}
1210
1211#if __GNUC__ >= 10
1212#  pragma GCC diagnostic pop
1213#endif
1214
1215/* Initialize global DFA and SSA structures.  */
1216
1217void
1218init_tree_ssa (struct function *fn)
1219{
1220  fn->gimple_df = ggc_cleared_alloc<gimple_df> ();
1221  fn->gimple_df->default_defs = hash_table<ssa_name_hasher>::create_ggc (20);
1222  pt_solution_reset (&fn->gimple_df->escaped);
1223  init_ssanames (fn, 0);
1224}
1225
1226/* Deallocate memory associated with SSA data structures for FNDECL.  */
1227
1228void
1229delete_tree_ssa (struct function *fn)
1230{
1231  fini_ssanames (fn);
1232
1233  /* We no longer maintain the SSA operand cache at this point.  */
1234  if (ssa_operands_active (fn))
1235    fini_ssa_operands (fn);
1236
1237  fn->gimple_df->default_defs->empty ();
1238  fn->gimple_df->default_defs = NULL;
1239  pt_solution_reset (&fn->gimple_df->escaped);
1240  if (fn->gimple_df->decls_to_pointers != NULL)
1241    delete fn->gimple_df->decls_to_pointers;
1242  fn->gimple_df->decls_to_pointers = NULL;
1243  fn->gimple_df = NULL;
1244
1245  /* We no longer need the edge variable maps.  */
1246  redirect_edge_var_map_empty ();
1247}
1248
1249/* Return true if EXPR is a useless type conversion, otherwise return
1250   false.  */
1251
1252bool
1253tree_ssa_useless_type_conversion (tree expr)
1254{
1255  /* If we have an assignment that merely uses a NOP_EXPR to change
1256     the top of the RHS to the type of the LHS and the type conversion
1257     is "safe", then strip away the type conversion so that we can
1258     enter LHS = RHS into the const_and_copies table.  */
1259  if (CONVERT_EXPR_P (expr)
1260      || TREE_CODE (expr) == VIEW_CONVERT_EXPR
1261      || TREE_CODE (expr) == NON_LVALUE_EXPR)
1262    return useless_type_conversion_p
1263      (TREE_TYPE (expr),
1264       TREE_TYPE (TREE_OPERAND (expr, 0)));
1265
1266  return false;
1267}
1268
1269/* Strip conversions from EXP according to
1270   tree_ssa_useless_type_conversion and return the resulting
1271   expression.  */
1272
1273tree
1274tree_ssa_strip_useless_type_conversions (tree exp)
1275{
1276  while (tree_ssa_useless_type_conversion (exp))
1277    exp = TREE_OPERAND (exp, 0);
1278  return exp;
1279}
1280
1281/* Return true if T, as SSA_NAME, has an implicit default defined value.  */
1282
1283bool
1284ssa_defined_default_def_p (tree t)
1285{
1286  tree var = SSA_NAME_VAR (t);
1287
1288  if (!var)
1289    ;
1290  /* Parameters get their initial value from the function entry.  */
1291  else if (TREE_CODE (var) == PARM_DECL)
1292    return true;
1293  /* When returning by reference the return address is actually a hidden
1294     parameter.  */
1295  else if (TREE_CODE (var) == RESULT_DECL && DECL_BY_REFERENCE (var))
1296    return true;
1297  /* Hard register variables get their initial value from the ether.  */
1298  else if (VAR_P (var) && DECL_HARD_REGISTER (var))
1299    return true;
1300
1301  return false;
1302}
1303
1304
1305/* Return true if T, an SSA_NAME, has an undefined value.  PARTIAL is what
1306   should be returned if the value is only partially undefined.  */
1307
1308bool
1309ssa_undefined_value_p (tree t, bool partial)
1310{
1311  gimple *def_stmt;
1312
1313  if (ssa_defined_default_def_p (t))
1314    return false;
1315
1316  /* The value is undefined iff its definition statement is empty.  */
1317  def_stmt = SSA_NAME_DEF_STMT (t);
1318  if (gimple_nop_p (def_stmt))
1319    return true;
1320
1321  /* Check if the complex was not only partially defined.  */
1322  if (partial && is_gimple_assign (def_stmt)
1323      && gimple_assign_rhs_code (def_stmt) == COMPLEX_EXPR)
1324    {
1325      tree rhs1, rhs2;
1326
1327      rhs1 = gimple_assign_rhs1 (def_stmt);
1328      rhs2 = gimple_assign_rhs2 (def_stmt);
1329      return (TREE_CODE (rhs1) == SSA_NAME && ssa_undefined_value_p (rhs1))
1330	     || (TREE_CODE (rhs2) == SSA_NAME && ssa_undefined_value_p (rhs2));
1331    }
1332  return false;
1333}
1334
1335
1336/* Return TRUE iff STMT, a gimple statement, references an undefined
1337   SSA name.  */
1338
1339bool
1340gimple_uses_undefined_value_p (gimple *stmt)
1341{
1342  ssa_op_iter iter;
1343  tree op;
1344
1345  FOR_EACH_SSA_TREE_OPERAND (op, stmt, iter, SSA_OP_USE)
1346    if (ssa_undefined_value_p (op))
1347      return true;
1348
1349  return false;
1350}
1351
1352
1353
1354/* If necessary, rewrite the base of the reference tree *TP from
1355   a MEM_REF to a plain or converted symbol.  */
1356
1357static void
1358maybe_rewrite_mem_ref_base (tree *tp, bitmap suitable_for_renaming)
1359{
1360  tree sym;
1361
1362  while (handled_component_p (*tp))
1363    tp = &TREE_OPERAND (*tp, 0);
1364  if (TREE_CODE (*tp) == MEM_REF
1365      && TREE_CODE (TREE_OPERAND (*tp, 0)) == ADDR_EXPR
1366      && (sym = TREE_OPERAND (TREE_OPERAND (*tp, 0), 0))
1367      && DECL_P (sym)
1368      && !TREE_ADDRESSABLE (sym)
1369      && bitmap_bit_p (suitable_for_renaming, DECL_UID (sym))
1370      && is_gimple_reg_type (TREE_TYPE (*tp))
1371      && ! VOID_TYPE_P (TREE_TYPE (*tp)))
1372    {
1373      if (TREE_CODE (TREE_TYPE (sym)) == VECTOR_TYPE
1374	  && useless_type_conversion_p (TREE_TYPE (*tp),
1375					TREE_TYPE (TREE_TYPE (sym)))
1376	  && multiple_of_p (sizetype, TREE_OPERAND (*tp, 1),
1377			    TYPE_SIZE_UNIT (TREE_TYPE (*tp))))
1378	{
1379	  *tp = build3 (BIT_FIELD_REF, TREE_TYPE (*tp), sym,
1380			TYPE_SIZE (TREE_TYPE (*tp)),
1381			int_const_binop (MULT_EXPR,
1382					 bitsize_int (BITS_PER_UNIT),
1383					 TREE_OPERAND (*tp, 1)));
1384	}
1385      else if (TREE_CODE (TREE_TYPE (sym)) == COMPLEX_TYPE
1386	       && useless_type_conversion_p (TREE_TYPE (*tp),
1387					     TREE_TYPE (TREE_TYPE (sym))))
1388	{
1389	  *tp = build1 (integer_zerop (TREE_OPERAND (*tp, 1))
1390			? REALPART_EXPR : IMAGPART_EXPR,
1391			TREE_TYPE (*tp), sym);
1392	}
1393      else if (integer_zerop (TREE_OPERAND (*tp, 1))
1394	       && DECL_SIZE (sym) == TYPE_SIZE (TREE_TYPE (*tp)))
1395	{
1396	  if (!useless_type_conversion_p (TREE_TYPE (*tp),
1397					  TREE_TYPE (sym)))
1398	    *tp = build1 (VIEW_CONVERT_EXPR,
1399			  TREE_TYPE (*tp), sym);
1400	  else
1401	    *tp = sym;
1402	}
1403      else if (DECL_SIZE (sym)
1404	       && TREE_CODE (DECL_SIZE (sym)) == INTEGER_CST
1405	       && (known_subrange_p
1406		   (mem_ref_offset (*tp),
1407		    wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (*tp))),
1408		    0, wi::to_offset (DECL_SIZE_UNIT (sym))))
1409	       && (! INTEGRAL_TYPE_P (TREE_TYPE (*tp))
1410		   || (wi::to_offset (TYPE_SIZE (TREE_TYPE (*tp)))
1411		       == TYPE_PRECISION (TREE_TYPE (*tp))))
1412	       && (! INTEGRAL_TYPE_P (TREE_TYPE (sym))
1413		   || type_has_mode_precision_p (TREE_TYPE (sym)))
1414	       && wi::umod_trunc (wi::to_offset (TYPE_SIZE (TREE_TYPE (*tp))),
1415				  BITS_PER_UNIT) == 0)
1416	{
1417	  *tp = build3 (BIT_FIELD_REF, TREE_TYPE (*tp), sym,
1418			TYPE_SIZE (TREE_TYPE (*tp)),
1419			wide_int_to_tree (bitsizetype,
1420					  mem_ref_offset (*tp)
1421					  << LOG2_BITS_PER_UNIT));
1422	}
1423    }
1424}
1425
1426/* For a tree REF return its base if it is the base of a MEM_REF
1427   that cannot be rewritten into SSA form.  Otherwise return NULL_TREE.  */
1428
1429static tree
1430non_rewritable_mem_ref_base (tree ref)
1431{
1432  tree base;
1433
1434  /* A plain decl does not need it set.  */
1435  if (DECL_P (ref))
1436    return NULL_TREE;
1437
1438  if (! (base = CONST_CAST_TREE (strip_invariant_refs (ref))))
1439    {
1440      base = get_base_address (ref);
1441      if (DECL_P (base))
1442	return base;
1443      return NULL_TREE;
1444    }
1445
1446  /* But watch out for MEM_REFs we cannot lower to a
1447     VIEW_CONVERT_EXPR or a BIT_FIELD_REF.  */
1448  if (TREE_CODE (base) == MEM_REF
1449      && TREE_CODE (TREE_OPERAND (base, 0)) == ADDR_EXPR)
1450    {
1451      tree decl = TREE_OPERAND (TREE_OPERAND (base, 0), 0);
1452      if (! DECL_P (decl))
1453	return NULL_TREE;
1454      if (! is_gimple_reg_type (TREE_TYPE (base))
1455	  || VOID_TYPE_P (TREE_TYPE (base))
1456	  || TREE_THIS_VOLATILE (decl) != TREE_THIS_VOLATILE (base))
1457	return decl;
1458      if ((TREE_CODE (TREE_TYPE (decl)) == VECTOR_TYPE
1459	   || TREE_CODE (TREE_TYPE (decl)) == COMPLEX_TYPE)
1460	  && useless_type_conversion_p (TREE_TYPE (base),
1461					TREE_TYPE (TREE_TYPE (decl)))
1462	  && known_ge (mem_ref_offset (base), 0)
1463	  && known_gt (wi::to_poly_offset (TYPE_SIZE_UNIT (TREE_TYPE (decl))),
1464		       mem_ref_offset (base))
1465	  && multiple_of_p (sizetype, TREE_OPERAND (base, 1),
1466			    TYPE_SIZE_UNIT (TREE_TYPE (base))))
1467	return NULL_TREE;
1468      /* For same sizes and zero offset we can use a VIEW_CONVERT_EXPR.  */
1469      if (integer_zerop (TREE_OPERAND (base, 1))
1470	  && DECL_SIZE (decl) == TYPE_SIZE (TREE_TYPE (base)))
1471	return NULL_TREE;
1472      /* For integral typed extracts we can use a BIT_FIELD_REF.  */
1473      if (DECL_SIZE (decl)
1474	  && TREE_CODE (DECL_SIZE_UNIT (decl)) == INTEGER_CST
1475	  && (known_subrange_p
1476	      (mem_ref_offset (base),
1477	       wi::to_poly_offset (TYPE_SIZE_UNIT (TREE_TYPE (base))),
1478	       0, wi::to_poly_offset (DECL_SIZE_UNIT (decl))))
1479	  /* ???  We can't handle bitfield precision extracts without
1480	     either using an alternate type for the BIT_FIELD_REF and
1481	     then doing a conversion or possibly adjusting the offset
1482	     according to endianness.  */
1483	  && (! INTEGRAL_TYPE_P (TREE_TYPE (base))
1484	      || (wi::to_offset (TYPE_SIZE (TREE_TYPE (base)))
1485		  == TYPE_PRECISION (TREE_TYPE (base))))
1486	  /* ???  Likewise for extracts from bitfields, we'd have
1487	     to pun the base object to a size precision mode first.  */
1488	  && (! INTEGRAL_TYPE_P (TREE_TYPE (decl))
1489	      || type_has_mode_precision_p (TREE_TYPE (decl)))
1490	  && wi::umod_trunc (wi::to_offset (TYPE_SIZE (TREE_TYPE (base))),
1491			     BITS_PER_UNIT) == 0)
1492	return NULL_TREE;
1493      return decl;
1494    }
1495
1496  return NULL_TREE;
1497}
1498
1499/* For an lvalue tree LHS return true if it cannot be rewritten into SSA form.
1500   Otherwise return true.  */
1501
1502static bool
1503non_rewritable_lvalue_p (tree lhs)
1504{
1505  /* A plain decl is always rewritable.  */
1506  if (DECL_P (lhs))
1507    return false;
1508
1509  /* We can re-write REALPART_EXPR and IMAGPART_EXPR sets in
1510     a reasonably efficient manner... */
1511  if ((TREE_CODE (lhs) == REALPART_EXPR
1512       || TREE_CODE (lhs) == IMAGPART_EXPR)
1513      && DECL_P (TREE_OPERAND (lhs, 0)))
1514    return false;
1515
1516  /* ???  The following could be relaxed allowing component
1517     references that do not change the access size.  */
1518  if (TREE_CODE (lhs) == MEM_REF
1519      && TREE_CODE (TREE_OPERAND (lhs, 0)) == ADDR_EXPR)
1520    {
1521      tree decl = TREE_OPERAND (TREE_OPERAND (lhs, 0), 0);
1522
1523      /* A decl that is wrapped inside a MEM-REF that covers
1524	 it full is also rewritable.  */
1525      if (integer_zerop (TREE_OPERAND (lhs, 1))
1526	  && DECL_P (decl)
1527	  && DECL_SIZE (decl) == TYPE_SIZE (TREE_TYPE (lhs))
1528	  /* If the dynamic type of the decl has larger precision than
1529	     the decl itself we can't use the decls type for SSA rewriting.  */
1530	  && ((! INTEGRAL_TYPE_P (TREE_TYPE (decl))
1531	       || compare_tree_int (DECL_SIZE (decl),
1532				    TYPE_PRECISION (TREE_TYPE (decl))) == 0)
1533	      || (INTEGRAL_TYPE_P (TREE_TYPE (lhs))
1534		  && (TYPE_PRECISION (TREE_TYPE (decl))
1535		      >= TYPE_PRECISION (TREE_TYPE (lhs)))))
1536	  /* Make sure we are not re-writing non-float copying into float
1537	     copying as that can incur normalization.  */
1538	  && (! FLOAT_TYPE_P (TREE_TYPE (decl))
1539	      || types_compatible_p (TREE_TYPE (lhs), TREE_TYPE (decl)))
1540	  && (TREE_THIS_VOLATILE (decl) == TREE_THIS_VOLATILE (lhs)))
1541	return false;
1542
1543      /* A vector-insert using a MEM_REF or ARRAY_REF is rewritable
1544	 using a BIT_INSERT_EXPR.  */
1545      if (DECL_P (decl)
1546	  && VECTOR_TYPE_P (TREE_TYPE (decl))
1547	  && TYPE_MODE (TREE_TYPE (decl)) != BLKmode
1548	  && known_ge (mem_ref_offset (lhs), 0)
1549	  && known_gt (wi::to_poly_offset (TYPE_SIZE_UNIT (TREE_TYPE (decl))),
1550		       mem_ref_offset (lhs))
1551	  && multiple_of_p (sizetype, TREE_OPERAND (lhs, 1),
1552			    TYPE_SIZE_UNIT (TREE_TYPE (lhs)))
1553	  && known_ge (wi::to_poly_offset (TYPE_SIZE (TREE_TYPE (decl))),
1554		       wi::to_poly_offset (TYPE_SIZE (TREE_TYPE (lhs)))))
1555	{
1556	  poly_uint64 lhs_bits, nelts;
1557	  if (poly_int_tree_p (TYPE_SIZE (TREE_TYPE (lhs)), &lhs_bits)
1558	      && multiple_p (lhs_bits,
1559			     tree_to_uhwi
1560			       (TYPE_SIZE (TREE_TYPE (TREE_TYPE (decl)))),
1561			     &nelts)
1562	      && valid_vector_subparts_p (nelts))
1563	    {
1564	      if (known_eq (nelts, 1u))
1565		return false;
1566	      /* For sub-vector inserts the insert vector mode has to be
1567		 supported.  */
1568	      tree vtype = build_vector_type (TREE_TYPE (TREE_TYPE (decl)),
1569					      nelts);
1570	      if (TYPE_MODE (vtype) != BLKmode)
1571		return false;
1572	    }
1573	}
1574    }
1575
1576  /* A vector-insert using a BIT_FIELD_REF is rewritable using
1577     BIT_INSERT_EXPR.  */
1578  if (TREE_CODE (lhs) == BIT_FIELD_REF
1579      && DECL_P (TREE_OPERAND (lhs, 0))
1580      && VECTOR_TYPE_P (TREE_TYPE (TREE_OPERAND (lhs, 0)))
1581      && TYPE_MODE (TREE_TYPE (TREE_OPERAND (lhs, 0))) != BLKmode
1582      && operand_equal_p (TYPE_SIZE_UNIT (TREE_TYPE (lhs)),
1583			  TYPE_SIZE_UNIT
1584			    (TREE_TYPE (TREE_TYPE (TREE_OPERAND (lhs, 0)))), 0)
1585      && (tree_to_uhwi (TREE_OPERAND (lhs, 2))
1586	  % tree_to_uhwi (TYPE_SIZE (TREE_TYPE (lhs)))) == 0)
1587    return false;
1588
1589  return true;
1590}
1591
1592/* When possible, clear TREE_ADDRESSABLE bit or set DECL_GIMPLE_REG_P bit and
1593   mark the variable VAR for conversion into SSA.  Return true when updating
1594   stmts is required.  */
1595
1596static void
1597maybe_optimize_var (tree var, bitmap addresses_taken, bitmap not_reg_needs,
1598		    bitmap suitable_for_renaming)
1599{
1600  /* Global Variables, result decls cannot be changed.  */
1601  if (is_global_var (var)
1602      || TREE_CODE (var) == RESULT_DECL
1603      || bitmap_bit_p (addresses_taken, DECL_UID (var)))
1604    return;
1605
1606  if (TREE_ADDRESSABLE (var)
1607      /* Do not change TREE_ADDRESSABLE if we need to preserve var as
1608	 a non-register.  Otherwise we are confused and forget to
1609	 add virtual operands for it.  */
1610      && (!is_gimple_reg_type (TREE_TYPE (var))
1611	  || TREE_CODE (TREE_TYPE (var)) == VECTOR_TYPE
1612	  || TREE_CODE (TREE_TYPE (var)) == COMPLEX_TYPE
1613	  || !bitmap_bit_p (not_reg_needs, DECL_UID (var))))
1614    {
1615      TREE_ADDRESSABLE (var) = 0;
1616      /* If we cleared TREE_ADDRESSABLE make sure DECL_GIMPLE_REG_P
1617         is unset if we cannot rewrite the var into SSA.  */
1618      if ((TREE_CODE (TREE_TYPE (var)) == VECTOR_TYPE
1619	   || TREE_CODE (TREE_TYPE (var)) == COMPLEX_TYPE)
1620	  && bitmap_bit_p (not_reg_needs, DECL_UID (var)))
1621	DECL_GIMPLE_REG_P (var) = 0;
1622      if (is_gimple_reg (var))
1623	bitmap_set_bit (suitable_for_renaming, DECL_UID (var));
1624      if (dump_file)
1625	{
1626	  fprintf (dump_file, "No longer having address taken: ");
1627	  print_generic_expr (dump_file, var);
1628	  fprintf (dump_file, "\n");
1629	}
1630    }
1631
1632  if (!DECL_GIMPLE_REG_P (var)
1633      && !bitmap_bit_p (not_reg_needs, DECL_UID (var))
1634      && (TREE_CODE (TREE_TYPE (var)) == COMPLEX_TYPE
1635	  || TREE_CODE (TREE_TYPE (var)) == VECTOR_TYPE)
1636      && !TREE_THIS_VOLATILE (var)
1637      && (!VAR_P (var) || !DECL_HARD_REGISTER (var)))
1638    {
1639      DECL_GIMPLE_REG_P (var) = 1;
1640      bitmap_set_bit (suitable_for_renaming, DECL_UID (var));
1641      if (dump_file)
1642	{
1643	  fprintf (dump_file, "Now a gimple register: ");
1644	  print_generic_expr (dump_file, var);
1645	  fprintf (dump_file, "\n");
1646	}
1647    }
1648}
1649
1650/* Return true when STMT is ASAN mark where second argument is an address
1651   of a local variable.  */
1652
1653static bool
1654is_asan_mark_p (gimple *stmt)
1655{
1656  if (!gimple_call_internal_p (stmt, IFN_ASAN_MARK))
1657    return false;
1658
1659  tree addr = get_base_address (gimple_call_arg (stmt, 1));
1660  if (TREE_CODE (addr) == ADDR_EXPR
1661      && VAR_P (TREE_OPERAND (addr, 0)))
1662    {
1663      tree var = TREE_OPERAND (addr, 0);
1664      if (lookup_attribute (ASAN_USE_AFTER_SCOPE_ATTRIBUTE,
1665			    DECL_ATTRIBUTES (var)))
1666	return false;
1667
1668      unsigned addressable = TREE_ADDRESSABLE (var);
1669      TREE_ADDRESSABLE (var) = 0;
1670      bool r = is_gimple_reg (var);
1671      TREE_ADDRESSABLE (var) = addressable;
1672      return r;
1673    }
1674
1675  return false;
1676}
1677
1678/* Compute TREE_ADDRESSABLE and DECL_GIMPLE_REG_P for local variables.  */
1679
1680void
1681execute_update_addresses_taken (void)
1682{
1683  basic_block bb;
1684  auto_bitmap addresses_taken;
1685  auto_bitmap not_reg_needs;
1686  auto_bitmap suitable_for_renaming;
1687  tree var;
1688  unsigned i;
1689
1690  timevar_push (TV_ADDRESS_TAKEN);
1691
1692  /* Collect into ADDRESSES_TAKEN all variables whose address is taken within
1693     the function body.  */
1694  FOR_EACH_BB_FN (bb, cfun)
1695    {
1696      for (gimple_stmt_iterator gsi = gsi_start_bb (bb); !gsi_end_p (gsi);
1697	   gsi_next (&gsi))
1698	{
1699	  gimple *stmt = gsi_stmt (gsi);
1700	  enum gimple_code code = gimple_code (stmt);
1701	  tree decl;
1702
1703	  if (code == GIMPLE_CALL)
1704	    {
1705	      if (optimize_atomic_compare_exchange_p (stmt))
1706		{
1707		  /* For __atomic_compare_exchange_N if the second argument
1708		     is &var, don't mark var addressable;
1709		     if it becomes non-addressable, we'll rewrite it into
1710		     ATOMIC_COMPARE_EXCHANGE call.  */
1711		  tree arg = gimple_call_arg (stmt, 1);
1712		  gimple_call_set_arg (stmt, 1, null_pointer_node);
1713		  gimple_ior_addresses_taken (addresses_taken, stmt);
1714		  gimple_call_set_arg (stmt, 1, arg);
1715		}
1716	      else if (is_asan_mark_p (stmt)
1717		       || gimple_call_internal_p (stmt, IFN_GOMP_SIMT_ENTER))
1718		;
1719	      else
1720		gimple_ior_addresses_taken (addresses_taken, stmt);
1721	    }
1722	  else
1723	    /* Note all addresses taken by the stmt.  */
1724	    gimple_ior_addresses_taken (addresses_taken, stmt);
1725
1726	  /* If we have a call or an assignment, see if the lhs contains
1727	     a local decl that requires not to be a gimple register.  */
1728	  if (code == GIMPLE_ASSIGN || code == GIMPLE_CALL)
1729	    {
1730              tree lhs = gimple_get_lhs (stmt);
1731              if (lhs
1732		  && TREE_CODE (lhs) != SSA_NAME
1733		  && ((code == GIMPLE_CALL && ! DECL_P (lhs))
1734		      || non_rewritable_lvalue_p (lhs)))
1735		{
1736		  decl = get_base_address (lhs);
1737		  if (DECL_P (decl))
1738		    bitmap_set_bit (not_reg_needs, DECL_UID (decl));
1739                }
1740	    }
1741
1742	  if (gimple_assign_single_p (stmt))
1743	    {
1744	      tree rhs = gimple_assign_rhs1 (stmt);
1745	      if ((decl = non_rewritable_mem_ref_base (rhs)))
1746		bitmap_set_bit (not_reg_needs, DECL_UID (decl));
1747	    }
1748
1749	  else if (code == GIMPLE_CALL)
1750	    {
1751	      for (i = 0; i < gimple_call_num_args (stmt); ++i)
1752		{
1753		  tree arg = gimple_call_arg (stmt, i);
1754		  if ((decl = non_rewritable_mem_ref_base (arg)))
1755		    bitmap_set_bit (not_reg_needs, DECL_UID (decl));
1756		}
1757	    }
1758
1759	  else if (code == GIMPLE_ASM)
1760	    {
1761	      gasm *asm_stmt = as_a <gasm *> (stmt);
1762	      for (i = 0; i < gimple_asm_noutputs (asm_stmt); ++i)
1763		{
1764		  tree link = gimple_asm_output_op (asm_stmt, i);
1765		  tree lhs = TREE_VALUE (link);
1766		  if (TREE_CODE (lhs) != SSA_NAME)
1767		    {
1768		      decl = get_base_address (lhs);
1769		      if (DECL_P (decl)
1770			  && (non_rewritable_lvalue_p (lhs)
1771			      /* We cannot move required conversions from
1772				 the lhs to the rhs in asm statements, so
1773				 require we do not need any.  */
1774			      || !useless_type_conversion_p
1775			            (TREE_TYPE (lhs), TREE_TYPE (decl))))
1776			bitmap_set_bit (not_reg_needs, DECL_UID (decl));
1777		    }
1778		}
1779	      for (i = 0; i < gimple_asm_ninputs (asm_stmt); ++i)
1780		{
1781		  tree link = gimple_asm_input_op (asm_stmt, i);
1782		  if ((decl = non_rewritable_mem_ref_base (TREE_VALUE (link))))
1783		    bitmap_set_bit (not_reg_needs, DECL_UID (decl));
1784		}
1785	    }
1786	}
1787
1788      for (gphi_iterator gsi = gsi_start_phis (bb); !gsi_end_p (gsi);
1789	   gsi_next (&gsi))
1790	{
1791	  size_t i;
1792	  gphi *phi = gsi.phi ();
1793
1794	  for (i = 0; i < gimple_phi_num_args (phi); i++)
1795	    {
1796	      tree op = PHI_ARG_DEF (phi, i), var;
1797	      if (TREE_CODE (op) == ADDR_EXPR
1798		  && (var = get_base_address (TREE_OPERAND (op, 0))) != NULL
1799		  && DECL_P (var))
1800		bitmap_set_bit (addresses_taken, DECL_UID (var));
1801	    }
1802	}
1803    }
1804
1805  /* We cannot iterate over all referenced vars because that can contain
1806     unused vars from BLOCK trees, which causes code generation differences
1807     for -g vs. -g0.  */
1808  for (var = DECL_ARGUMENTS (cfun->decl); var; var = DECL_CHAIN (var))
1809    maybe_optimize_var (var, addresses_taken, not_reg_needs,
1810			suitable_for_renaming);
1811
1812  FOR_EACH_VEC_SAFE_ELT (cfun->local_decls, i, var)
1813    maybe_optimize_var (var, addresses_taken, not_reg_needs,
1814			suitable_for_renaming);
1815
1816  /* Operand caches need to be recomputed for operands referencing the updated
1817     variables and operands need to be rewritten to expose bare symbols.  */
1818  if (!bitmap_empty_p (suitable_for_renaming))
1819    {
1820      FOR_EACH_BB_FN (bb, cfun)
1821	for (gimple_stmt_iterator gsi = gsi_start_bb (bb); !gsi_end_p (gsi);)
1822	  {
1823	    gimple *stmt = gsi_stmt (gsi);
1824
1825	    /* Re-write TARGET_MEM_REFs of symbols we want to
1826	       rewrite into SSA form.  */
1827	    if (gimple_assign_single_p (stmt))
1828	      {
1829		tree lhs = gimple_assign_lhs (stmt);
1830		tree rhs, *rhsp = gimple_assign_rhs1_ptr (stmt);
1831		tree sym;
1832
1833		/* Rewrite LHS IMAG/REALPART_EXPR similar to
1834		   gimplify_modify_expr_complex_part.  */
1835		if ((TREE_CODE (lhs) == IMAGPART_EXPR
1836		     || TREE_CODE (lhs) == REALPART_EXPR)
1837		    && DECL_P (TREE_OPERAND (lhs, 0))
1838		    && bitmap_bit_p (suitable_for_renaming,
1839				     DECL_UID (TREE_OPERAND (lhs, 0))))
1840		  {
1841		    tree other = make_ssa_name (TREE_TYPE (lhs));
1842		    tree lrhs = build1 (TREE_CODE (lhs) == IMAGPART_EXPR
1843					? REALPART_EXPR : IMAGPART_EXPR,
1844					TREE_TYPE (other),
1845					TREE_OPERAND (lhs, 0));
1846		    gimple *load = gimple_build_assign (other, lrhs);
1847		    location_t loc = gimple_location (stmt);
1848		    gimple_set_location (load, loc);
1849		    gimple_set_vuse (load, gimple_vuse (stmt));
1850		    gsi_insert_before (&gsi, load, GSI_SAME_STMT);
1851		    gimple_assign_set_lhs (stmt, TREE_OPERAND (lhs, 0));
1852		    gimple_assign_set_rhs_with_ops
1853		      (&gsi, COMPLEX_EXPR,
1854		       TREE_CODE (lhs) == IMAGPART_EXPR
1855		       ? other : gimple_assign_rhs1 (stmt),
1856		       TREE_CODE (lhs) == IMAGPART_EXPR
1857		       ? gimple_assign_rhs1 (stmt) : other, NULL_TREE);
1858		    stmt = gsi_stmt (gsi);
1859		    unlink_stmt_vdef (stmt);
1860		    update_stmt (stmt);
1861		    continue;
1862		  }
1863
1864		/* Rewrite a vector insert via a BIT_FIELD_REF on the LHS
1865		   into a BIT_INSERT_EXPR.  */
1866		if (TREE_CODE (lhs) == BIT_FIELD_REF
1867		    && DECL_P (TREE_OPERAND (lhs, 0))
1868		    && bitmap_bit_p (suitable_for_renaming,
1869				     DECL_UID (TREE_OPERAND (lhs, 0)))
1870		    && VECTOR_TYPE_P (TREE_TYPE (TREE_OPERAND (lhs, 0)))
1871		    && TYPE_MODE (TREE_TYPE (TREE_OPERAND (lhs, 0))) != BLKmode
1872		    && operand_equal_p (TYPE_SIZE_UNIT (TREE_TYPE (lhs)),
1873					TYPE_SIZE_UNIT (TREE_TYPE
1874					  (TREE_TYPE (TREE_OPERAND (lhs, 0)))),
1875					0)
1876		    && (tree_to_uhwi (TREE_OPERAND (lhs, 2))
1877			% tree_to_uhwi (TYPE_SIZE (TREE_TYPE (lhs))) == 0))
1878		  {
1879		    tree var = TREE_OPERAND (lhs, 0);
1880		    tree val = gimple_assign_rhs1 (stmt);
1881		    if (! types_compatible_p (TREE_TYPE (TREE_TYPE (var)),
1882					      TREE_TYPE (val)))
1883		      {
1884			tree tem = make_ssa_name (TREE_TYPE (TREE_TYPE (var)));
1885			gimple *pun
1886			  = gimple_build_assign (tem,
1887						 build1 (VIEW_CONVERT_EXPR,
1888							 TREE_TYPE (tem), val));
1889			gsi_insert_before (&gsi, pun, GSI_SAME_STMT);
1890			val = tem;
1891		      }
1892		    tree bitpos = TREE_OPERAND (lhs, 2);
1893		    gimple_assign_set_lhs (stmt, var);
1894		    gimple_assign_set_rhs_with_ops
1895		      (&gsi, BIT_INSERT_EXPR, var, val, bitpos);
1896		    stmt = gsi_stmt (gsi);
1897		    unlink_stmt_vdef (stmt);
1898		    update_stmt (stmt);
1899		    continue;
1900		  }
1901
1902		/* Rewrite a vector insert using a MEM_REF on the LHS
1903		   into a BIT_INSERT_EXPR.  */
1904		if (TREE_CODE (lhs) == MEM_REF
1905		    && TREE_CODE (TREE_OPERAND (lhs, 0)) == ADDR_EXPR
1906		    && (sym = TREE_OPERAND (TREE_OPERAND (lhs, 0), 0))
1907		    && DECL_P (sym)
1908		    && bitmap_bit_p (suitable_for_renaming, DECL_UID (sym))
1909		    && VECTOR_TYPE_P (TREE_TYPE (sym))
1910		    && TYPE_MODE (TREE_TYPE (sym)) != BLKmode
1911		    /* If it is a full replacement we can do better below.  */
1912		    && maybe_ne (wi::to_poly_offset
1913				   (TYPE_SIZE_UNIT (TREE_TYPE (lhs))),
1914				 wi::to_poly_offset
1915                                   (TYPE_SIZE_UNIT (TREE_TYPE (sym))))
1916		    && known_ge (mem_ref_offset (lhs), 0)
1917		    && known_gt (wi::to_poly_offset
1918				   (TYPE_SIZE_UNIT (TREE_TYPE (sym))),
1919				 mem_ref_offset (lhs))
1920		    && multiple_of_p (sizetype,
1921				      TREE_OPERAND (lhs, 1),
1922				      TYPE_SIZE_UNIT (TREE_TYPE (lhs))))
1923		  {
1924		    tree val = gimple_assign_rhs1 (stmt);
1925		    if (! types_compatible_p (TREE_TYPE (val),
1926					      TREE_TYPE (TREE_TYPE (sym))))
1927		      {
1928			poly_uint64 lhs_bits, nelts;
1929			tree temtype = TREE_TYPE (TREE_TYPE (sym));
1930			if (poly_int_tree_p (TYPE_SIZE (TREE_TYPE (lhs)),
1931					     &lhs_bits)
1932			    && multiple_p (lhs_bits,
1933					   tree_to_uhwi
1934					     (TYPE_SIZE (TREE_TYPE
1935							   (TREE_TYPE (sym)))),
1936					   &nelts)
1937			    && maybe_ne (nelts, 1u)
1938			    && valid_vector_subparts_p (nelts))
1939			  temtype = build_vector_type (temtype, nelts);
1940			tree tem = make_ssa_name (temtype);
1941			gimple *pun
1942			  = gimple_build_assign (tem,
1943						 build1 (VIEW_CONVERT_EXPR,
1944							 TREE_TYPE (tem), val));
1945			gsi_insert_before (&gsi, pun, GSI_SAME_STMT);
1946			val = tem;
1947		      }
1948		    tree bitpos
1949		      = wide_int_to_tree (bitsizetype,
1950					  mem_ref_offset (lhs) * BITS_PER_UNIT);
1951		    gimple_assign_set_lhs (stmt, sym);
1952		    gimple_assign_set_rhs_with_ops
1953		      (&gsi, BIT_INSERT_EXPR, sym, val, bitpos);
1954		    stmt = gsi_stmt (gsi);
1955		    unlink_stmt_vdef (stmt);
1956		    update_stmt (stmt);
1957		    continue;
1958		  }
1959
1960		/* We shouldn't have any fancy wrapping of
1961		   component-refs on the LHS, but look through
1962		   VIEW_CONVERT_EXPRs as that is easy.  */
1963		while (TREE_CODE (lhs) == VIEW_CONVERT_EXPR)
1964		  lhs = TREE_OPERAND (lhs, 0);
1965		if (TREE_CODE (lhs) == MEM_REF
1966		    && TREE_CODE (TREE_OPERAND (lhs, 0)) == ADDR_EXPR
1967		    && integer_zerop (TREE_OPERAND (lhs, 1))
1968		    && (sym = TREE_OPERAND (TREE_OPERAND (lhs, 0), 0))
1969		    && DECL_P (sym)
1970		    && !TREE_ADDRESSABLE (sym)
1971		    && bitmap_bit_p (suitable_for_renaming, DECL_UID (sym)))
1972		  lhs = sym;
1973		else
1974		  lhs = gimple_assign_lhs (stmt);
1975
1976		/* Rewrite the RHS and make sure the resulting assignment
1977		   is validly typed.  */
1978		maybe_rewrite_mem_ref_base (rhsp, suitable_for_renaming);
1979		rhs = gimple_assign_rhs1 (stmt);
1980		if (gimple_assign_lhs (stmt) != lhs
1981		    && !useless_type_conversion_p (TREE_TYPE (lhs),
1982						   TREE_TYPE (rhs)))
1983		  {
1984		    if (gimple_clobber_p (stmt))
1985		      {
1986			rhs = build_constructor (TREE_TYPE (lhs), NULL);
1987			TREE_THIS_VOLATILE (rhs) = 1;
1988		      }
1989		    else
1990		      rhs = fold_build1 (VIEW_CONVERT_EXPR,
1991					 TREE_TYPE (lhs), rhs);
1992		  }
1993		if (gimple_assign_lhs (stmt) != lhs)
1994		  gimple_assign_set_lhs (stmt, lhs);
1995
1996		if (gimple_assign_rhs1 (stmt) != rhs)
1997		  {
1998		    gimple_stmt_iterator gsi = gsi_for_stmt (stmt);
1999		    gimple_assign_set_rhs_from_tree (&gsi, rhs);
2000		  }
2001	      }
2002
2003	    else if (gimple_code (stmt) == GIMPLE_CALL)
2004	      {
2005		unsigned i;
2006		if (optimize_atomic_compare_exchange_p (stmt))
2007		  {
2008		    tree expected = gimple_call_arg (stmt, 1);
2009		    if (bitmap_bit_p (suitable_for_renaming,
2010				      DECL_UID (TREE_OPERAND (expected, 0))))
2011		      {
2012			fold_builtin_atomic_compare_exchange (&gsi);
2013			continue;
2014		      }
2015		  }
2016		else if (is_asan_mark_p (stmt))
2017		  {
2018		    tree var = TREE_OPERAND (gimple_call_arg (stmt, 1), 0);
2019		    if (bitmap_bit_p (suitable_for_renaming, DECL_UID (var)))
2020		      {
2021			unlink_stmt_vdef (stmt);
2022			if (asan_mark_p (stmt, ASAN_MARK_POISON))
2023			  {
2024			    gcall *call
2025			      = gimple_build_call_internal (IFN_ASAN_POISON, 0);
2026			    gimple_call_set_lhs (call, var);
2027			    gsi_replace (&gsi, call, GSI_SAME_STMT);
2028			  }
2029			else
2030			  {
2031			    /* In ASAN_MARK (UNPOISON, &b, ...) the variable
2032			       is uninitialized.  Avoid dependencies on
2033			       previous out of scope value.  */
2034			    tree clobber = build_clobber (TREE_TYPE (var));
2035			    gimple *g = gimple_build_assign (var, clobber);
2036			    gsi_replace (&gsi, g, GSI_SAME_STMT);
2037			  }
2038			continue;
2039		      }
2040		  }
2041		else if (gimple_call_internal_p (stmt, IFN_GOMP_SIMT_ENTER))
2042		  for (i = 1; i < gimple_call_num_args (stmt); i++)
2043		    {
2044		      tree *argp = gimple_call_arg_ptr (stmt, i);
2045		      if (*argp == null_pointer_node)
2046			continue;
2047		      gcc_assert (TREE_CODE (*argp) == ADDR_EXPR
2048				  && VAR_P (TREE_OPERAND (*argp, 0)));
2049		      tree var = TREE_OPERAND (*argp, 0);
2050		      if (bitmap_bit_p (suitable_for_renaming, DECL_UID (var)))
2051			*argp = null_pointer_node;
2052		    }
2053		for (i = 0; i < gimple_call_num_args (stmt); ++i)
2054		  {
2055		    tree *argp = gimple_call_arg_ptr (stmt, i);
2056		    maybe_rewrite_mem_ref_base (argp, suitable_for_renaming);
2057		  }
2058	      }
2059
2060	    else if (gimple_code (stmt) == GIMPLE_ASM)
2061	      {
2062		gasm *asm_stmt = as_a <gasm *> (stmt);
2063		unsigned i;
2064		for (i = 0; i < gimple_asm_noutputs (asm_stmt); ++i)
2065		  {
2066		    tree link = gimple_asm_output_op (asm_stmt, i);
2067		    maybe_rewrite_mem_ref_base (&TREE_VALUE (link),
2068						suitable_for_renaming);
2069		  }
2070		for (i = 0; i < gimple_asm_ninputs (asm_stmt); ++i)
2071		  {
2072		    tree link = gimple_asm_input_op (asm_stmt, i);
2073		    maybe_rewrite_mem_ref_base (&TREE_VALUE (link),
2074						suitable_for_renaming);
2075		  }
2076	      }
2077
2078	    else if (gimple_debug_bind_p (stmt)
2079		     && gimple_debug_bind_has_value_p (stmt))
2080	      {
2081		tree *valuep = gimple_debug_bind_get_value_ptr (stmt);
2082		tree decl;
2083		maybe_rewrite_mem_ref_base (valuep, suitable_for_renaming);
2084		decl = non_rewritable_mem_ref_base (*valuep);
2085		if (decl
2086		    && bitmap_bit_p (suitable_for_renaming, DECL_UID (decl)))
2087		  gimple_debug_bind_reset_value (stmt);
2088	      }
2089
2090	    if (gimple_references_memory_p (stmt)
2091		|| is_gimple_debug (stmt))
2092	      update_stmt (stmt);
2093
2094	    gsi_next (&gsi);
2095	  }
2096
2097      /* Update SSA form here, we are called as non-pass as well.  */
2098      if (number_of_loops (cfun) > 1
2099	  && loops_state_satisfies_p (LOOP_CLOSED_SSA))
2100	rewrite_into_loop_closed_ssa (NULL, TODO_update_ssa);
2101      else
2102	update_ssa (TODO_update_ssa);
2103    }
2104
2105  timevar_pop (TV_ADDRESS_TAKEN);
2106}
2107
2108namespace {
2109
2110const pass_data pass_data_update_address_taken =
2111{
2112  GIMPLE_PASS, /* type */
2113  "addressables", /* name */
2114  OPTGROUP_NONE, /* optinfo_flags */
2115  TV_ADDRESS_TAKEN, /* tv_id */
2116  PROP_ssa, /* properties_required */
2117  0, /* properties_provided */
2118  0, /* properties_destroyed */
2119  0, /* todo_flags_start */
2120  TODO_update_address_taken, /* todo_flags_finish */
2121};
2122
2123class pass_update_address_taken : public gimple_opt_pass
2124{
2125public:
2126  pass_update_address_taken (gcc::context *ctxt)
2127    : gimple_opt_pass (pass_data_update_address_taken, ctxt)
2128  {}
2129
2130  /* opt_pass methods: */
2131
2132}; // class pass_update_address_taken
2133
2134} // anon namespace
2135
2136gimple_opt_pass *
2137make_pass_update_address_taken (gcc::context *ctxt)
2138{
2139  return new pass_update_address_taken (ctxt);
2140}
2141