bitmap.c (bitmap_elem_to_freelist): Set indx to -1.

2016-10-07  Richard Biener  <rguenther@suse.de>

	* bitmap.c (bitmap_elem_to_freelist): Set indx to -1.
	* bitmap.h (bmp_iter_set): When advancing to the next element
	check that we didn't remove the current one.
	(bmp_iter_and): Likewise.
	(bmp_iter_and_compl): Likewise.
	* tree-ssa.c (release_defs_bitset): Do not remove worklist bit
	we currently iterate on but keep a one-level queue.
	* sched-deps.c (remove_from_deps): Do not clear current bit
	but keep a one-level queue.

From-SVN: r240859

gcc/ChangeLog

+2016-10-07  Richard Biener  <rguenther@suse.de>
+
+	* bitmap.c (bitmap_elem_to_freelist): Set indx to -1.
+	* bitmap.h (bmp_iter_set): When advancing to the next element
+	check that we didn't remove the current one.
+	(bmp_iter_and): Likewise.
+	(bmp_iter_and_compl): Likewise.
+	* tree-ssa.c (release_defs_bitset): Do not remove worklist bit
+	we currently iterate on but keep a one-level queue.
+	* sched-deps.c (remove_from_deps): Do not clear current bit
+	but keep a one-level queue.
+
 2016-10-07  Jakub Jelinek  <jakub@redhat.com>
 
 	PR tree-optimization/77664

gcc/bitmap.c

@@ -66,6 +66,7 @@ bitmap_elem_to_freelist (bitmap head, bitmap_element *elt)
   bitmap_obstack *bit_obstack = head->obstack;
 
   elt->next = NULL;
+  elt->indx = -1;
   if (bit_obstack)
     {
       elt->prev = bit_obstack->elements;

gcc/bitmap.h

@@ -618,6 +618,9 @@ bmp_iter_set (bitmap_iterator *bi, unsigned *bit_no)
 	  bi->word_no++;
 	}
 
+      /* Make sure we didn't remove the element while iterating.  */
+      gcc_checking_assert (bi->elt1->indx != -1U);
+
       /* Advance to the next element.  */
       bi->elt1 = bi->elt1->next;
       if (!bi->elt1)
@@ -664,6 +667,9 @@ bmp_iter_and (bitmap_iterator *bi, unsigned *bit_no)
       /* Advance to the next identical element.  */
       do
 	{
+	  /* Make sure we didn't remove the element while iterating.  */
+	  gcc_checking_assert (bi->elt1->indx != -1U);
+
 	  /* Advance elt1 while it is less than elt2.  We always want
 	     to advance one elt.  */
 	  do
@@ -674,6 +680,9 @@ bmp_iter_and (bitmap_iterator *bi, unsigned *bit_no)
 	    }
 	  while (bi->elt1->indx < bi->elt2->indx);
 
+	  /* Make sure we didn't remove the element while iterating.  */
+	  gcc_checking_assert (bi->elt2->indx != -1U);
+
 	  /* Advance elt2 to be no less than elt1.  This might not
 	     advance.  */
 	  while (bi->elt2->indx < bi->elt1->indx)
@@ -726,11 +735,17 @@ bmp_iter_and_compl (bitmap_iterator *bi, unsigned *bit_no)
 	  bi->word_no++;
 	}
 
+      /* Make sure we didn't remove the element while iterating.  */
+      gcc_checking_assert (bi->elt1->indx != -1U);
+
       /* Advance to the next element of elt1.  */
       bi->elt1 = bi->elt1->next;
       if (!bi->elt1)
 	return false;
 
+      /* Make sure we didn't remove the element while iterating.  */
+      gcc_checking_assert (! bi->elt2 || bi->elt2->indx != -1U);
+
       /* Advance elt2 until it is no less than elt1.  */
       while (bi->elt2 && bi->elt2->indx < bi->elt1->indx)
 	bi->elt2 = bi->elt2->next;

gcc/sched-deps.c

@@ -3992,8 +3992,14 @@ remove_from_deps (struct deps_desc *deps, rtx_insn *insn)
   removed = remove_from_dependence_list (insn, &deps->last_pending_memory_flush);
   deps->pending_flush_length -= removed;
 
+  unsigned to_clear = -1U;
   EXECUTE_IF_SET_IN_REG_SET (&deps->reg_last_in_use, 0, i, rsi)
     {
+      if (to_clear != -1U)
+	{
+	  CLEAR_REGNO_REG_SET (&deps->reg_last_in_use, to_clear);
+	  to_clear = -1U;
+	}
       struct deps_reg *reg_last = &deps->reg_last[i];
       if (reg_last->uses)
 	remove_from_dependence_list (insn, &reg_last->uses);
@@ -4005,8 +4011,10 @@ remove_from_deps (struct deps_desc *deps, rtx_insn *insn)
 	remove_from_dependence_list (insn, &reg_last->clobbers);
       if (!reg_last->uses && !reg_last->sets && !reg_last->implicit_sets
 	  && !reg_last->clobbers)
-        CLEAR_REGNO_REG_SET (&deps->reg_last_in_use, i);
+	to_clear = i;
     }
+  if (to_clear != -1U)
+    CLEAR_REGNO_REG_SET (&deps->reg_last_in_use, to_clear);
 
   if (CALL_P (insn))
     {

gcc/tree-ssa.c

@@ -551,8 +551,16 @@ release_defs_bitset (bitmap toremove)
      most likely run in slightly superlinear time, rather than the
      pathological quadratic worst case.  */
   while (!bitmap_empty_p (toremove))
+    {
+      unsigned to_remove_bit = -1U;
       EXECUTE_IF_SET_IN_BITMAP (toremove, 0, j, bi)
 	{
+	  if (to_remove_bit != -1U)
+	    {
+	      bitmap_clear_bit (toremove, to_remove_bit);
+	      to_remove_bit = -1U;
+	    }
+
 	  bool remove_now = true;
 	  tree var = ssa_name (j);
 	  gimple *stmt;
@@ -600,9 +608,13 @@ release_defs_bitset (bitmap toremove)
 		  release_defs (def);
 		}
 
-	    bitmap_clear_bit (toremove, j);
+	      to_remove_bit = j;
+	    }
 	}
+      if (to_remove_bit != -1U)
+	bitmap_clear_bit (toremove, to_remove_bit);
     }
+
 }
 
 /* Verify virtual SSA form.  */