add bitmap_head::swap

4 files changed, 20 insertions, 16 deletions

diff --git a/gcc/bitmap.c b/gcc/bitmap.c
index 9d8ebc74558..dfebc11adca 100644
--- a/gcc/bitmap.c
+++ b/gcc/bitmap.c
@@ -20,6 +20,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "config.h"
 #include "system.h"
 #include "coretypes.h"
+#include <utility>
 #include "obstack.h"
 #include "ggc.h"
 #include "bitmap.h"
@@ -2223,5 +2224,14 @@ debug (const bitmap_head *ptr)
     fprintf (stderr, "<nil>\n");
 }
 
+void
+bitmap_head::swap (bitmap_head *other)
+{
+  other->indx = indx = 0;
+  other->current = current = NULL;
+  std::swap (other->descriptor_id, descriptor_id);
+  std::swap (other->first, first);
+  std::swap (other->obstack, obstack);
+}
 
 #include "gt-bitmap.h"
diff --git a/gcc/bitmap.h b/gcc/bitmap.h
index 98da3c11f6d..d6f2be57d55 100644
--- a/gcc/bitmap.h
+++ b/gcc/bitmap.h
@@ -199,6 +199,8 @@ struct GTY(()) bitmap_head {
   }
   ~bitmap_head () { bitmap_clear (this); }
 
+  void swap (bitmap_head *);
+
   unsigned int indx;			/* Index of last element looked at.  */
   unsigned int descriptor_id;		/* Unique identifier for the allocation
 					   site of this bitmap, for detailed
diff --git a/gcc/df-problems.c b/gcc/df-problems.c
index 9149eda6d34..1d4476471bb 100644
--- a/gcc/df-problems.c
+++ b/gcc/df-problems.c
@@ -534,9 +534,7 @@ df_rd_transfer_function (int bb_index)
       if (changed)
 	{
 	  bitmap_clear (out);
-	  bb_info->out = tmp;
-    // kind of hacky but hopefully that'll be fixed by more c++ification
-     tmp.first = tmp.current = NULL;
+	  tmp.swap (&bb_info->out);
 	}
       else
 	bitmap_clear (&tmp);
@@ -1284,8 +1282,6 @@ df_lr_verify_transfer_functions (void)
   if (!df)
     return;
 
-  bitmap_head saved_def;
-  bitmap_head saved_use;
   bitmap_head all_blocks;
   FOR_ALL_BB_FN (bb, cfun)
     {
@@ -1300,10 +1296,9 @@ df_lr_verify_transfer_functions (void)
 	  if (!bitmap_bit_p (df_lr->out_of_date_transfer_functions,
 			     bb->index))
 	    {
-	      bitmap_copy (&saved_def, &bb_info->def);
-	      bitmap_copy (&saved_use, &bb_info->use);
-	      bitmap_clear (&bb_info->def);
-	      bitmap_clear (&bb_info->use);
+        bitmap_head saved_def, saved_use;
+	      saved_def.swap (&bb_info->def);
+	      saved_use.swap (&bb_info->use);
 
 	      df_lr_bb_local_compute (bb->index);
 	      gcc_assert (bitmap_equal_p (&saved_def, &bb_info->def));
@@ -1820,8 +1815,6 @@ df_live_verify_transfer_functions (void)
   if (!df)
     return;
 
-  bitmap_head saved_gen;
-  bitmap_head saved_kill;
   bitmap_head all_blocks;
   df_grow_insn_info ();
 
@@ -1838,10 +1831,9 @@ df_live_verify_transfer_functions (void)
 	  if (!bitmap_bit_p (df_live->out_of_date_transfer_functions,
 			     bb->index))
 	    {
-	      bitmap_copy (&saved_gen, &bb_info->gen);
-	      bitmap_copy (&saved_kill, &bb_info->kill);
-	      bitmap_clear (&bb_info->gen);
-	      bitmap_clear (&bb_info->kill);
+	      bitmap_head saved_gen, saved_kill;
+	      saved_gen.swap (&bb_info->gen);
+	      saved_kill.swap (&bb_info->kill);
 
 	      df_live_bb_local_compute (bb->index);
 	      gcc_assert (bitmap_equal_p (&saved_gen, &bb_info->gen));
diff --git a/gcc/ira.c b/gcc/ira.c
index 32134b8e23a..c9078014dd9 100644
--- a/gcc/ira.c
+++ b/gcc/ira.c
@@ -4529,7 +4529,7 @@ find_moveable_pseudos (void)
 
       bitmap_head live (*df_get_live_out (bb));
       bitmap_and_into (&live, df_get_live_in (bb));
-      bitmap_copy (transp, &live);
+      transp->swap (&live);
       bitmap_head set;
       FOR_BB_INSNS (bb, insn)
 	if (NONDEBUG_INSN_P (insn))