* flow.c (count_or_remove_death_notes_bb): New. Extracted from

        count_or_remove_death_notes.
        (count_or_remove_death_notes): Use EXECUTE_IF_SET_IN_SBITMAP.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@74111 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 989c689..00e4063 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2003-12-01  Jeff Law  <law@redhat.com>
+
+       * flow.c (count_or_remove_death_notes_bb): New.  Extracted from
+       count_or_remove_death_notes.
+       (count_or_remove_death_notes): Use EXECUTE_IF_SET_IN_SBITMAP.
+
 2003-12-01  Andreas Krebbel  <krebbel1@de.ibm.com>
 
        * builtins.c (expand_builtin_longjmp): Added two memory clobbers.

diff --git a/gcc/flow.c b/gcc/flow.c
index 0dffb46..d131fab 100644 (file)
--- a/gcc/flow.c
+++ b/gcc/flow.c
@@ -326,6 +326,7 @@ static void add_to_mem_set_list (struct propagate_block_info *, rtx);
 static int invalidate_mems_from_autoinc (rtx *, void *);
 static void invalidate_mems_from_set (struct propagate_block_info *, rtx);
 static void clear_log_links (sbitmap);
+static int count_or_remove_death_notes_bb (basic_block, int);
 \f
 
 void
@@ -4168,65 +4169,95 @@ int
 count_or_remove_death_notes (sbitmap blocks, int kill)
 {
   int count = 0;
+  int i;
   basic_block bb;
 
-  FOR_EACH_BB_REVERSE (bb)
+  
+  /* This used to be a loop over all the blocks with a membership test
+     inside the loop.  That can be amazingly expensive on a large CFG
+     when only a small number of bits are set in BLOCKs (for example,
+     the calls from the scheduler typically have very few bits set).
+
+     For extra credit, someone should convert BLOCKS to a bitmap rather
+     than an sbitmap.  */
+  if (blocks)
+    {
+      EXECUTE_IF_SET_IN_SBITMAP (blocks, 0, i,
+       {
+         count += count_or_remove_death_notes_bb (BASIC_BLOCK (i), kill);
+       });
+    }
+  else
     {
-      rtx insn;
+      FOR_EACH_BB (bb)
+       {
+         count += count_or_remove_death_notes_bb (bb, kill);
+       }
+    }
 
-      if (blocks && ! TEST_BIT (blocks, bb->index))
-       continue;
+  return count;
+}
+  
+/* Optionally removes all the REG_DEAD and REG_UNUSED notes from basic
+   block BB.  Returns a count of the number of registers that died.  */
+
+static int
+count_or_remove_death_notes_bb (basic_block bb, int kill)
+{
+  int count = 0;
+  rtx insn;
 
-      for (insn = bb->head;; insn = NEXT_INSN (insn))
+  for (insn = bb->head;; insn = NEXT_INSN (insn))
+    {
+      if (INSN_P (insn))
        {
-         if (INSN_P (insn))
-           {
-             rtx *pprev = &REG_NOTES (insn);
-             rtx link = *pprev;
+         rtx *pprev = &REG_NOTES (insn);
+         rtx link = *pprev;
 
-             while (link)
+         while (link)
+           {
+             switch (REG_NOTE_KIND (link))
                {
-                 switch (REG_NOTE_KIND (link))
+               case REG_DEAD:
+                 if (GET_CODE (XEXP (link, 0)) == REG)
                    {
-                   case REG_DEAD:
-                     if (GET_CODE (XEXP (link, 0)) == REG)
-                       {
-                         rtx reg = XEXP (link, 0);
-                         int n;
-
-                         if (REGNO (reg) >= FIRST_PSEUDO_REGISTER)
-                           n = 1;
-                         else
-                           n = HARD_REGNO_NREGS (REGNO (reg), GET_MODE (reg));
-                         count += n;
-                       }
-                     /* Fall through.  */
-
-                   case REG_UNUSED:
-                     if (kill)
-                       {
-                         rtx next = XEXP (link, 1);
-                         free_EXPR_LIST_node (link);
-                         *pprev = link = next;
-                         break;
-                       }
-                     /* Fall through.  */
-
-                   default:
-                     pprev = &XEXP (link, 1);
-                     link = *pprev;
+                     rtx reg = XEXP (link, 0);
+                     int n;
+
+                     if (REGNO (reg) >= FIRST_PSEUDO_REGISTER)
+                       n = 1;
+                     else
+                       n = HARD_REGNO_NREGS (REGNO (reg), GET_MODE (reg));
+                     count += n;
+                   }
+
+                 /* Fall through.  */
+
+               case REG_UNUSED:
+                 if (kill)
+                   {
+                     rtx next = XEXP (link, 1);
+                     free_EXPR_LIST_node (link);
+                     *pprev = link = next;
                      break;
                    }
+                 /* Fall through.  */
+
+               default:
+                 pprev = &XEXP (link, 1);
+                 link = *pprev;
+                 break;
                }
            }
-
-         if (insn == bb->end)
-           break;
        }
+
+      if (insn == bb->end)
+       break;
     }
 
   return count;
 }
+
 /* Clear LOG_LINKS fields of insns in a selected blocks or whole chain
    if blocks is NULL.  */