* flow.c (recompute_reg_usage): Use basic block info to get loop_depth.

From-SVN: r30843

gcc/ChangeLog

 Thu Dec  9 11:36:24 MET 1999 Jan Hubicka  <hubicka@freesoft.cz>
 
+	* flow.c (recompute_reg_usage): Use basic block info to get loop_depth.
+
 	* combine.c (try_combine, distribute_notes): Remove REG_N_REFS
 	updating code.
 

gcc/flow.c

@@ -5578,6 +5578,7 @@ recompute_reg_usage (f, loop_step)
 {
   rtx insn;
   int i, max_reg;
+  int index;
 
   /* Clear out the old data.  */
   max_reg = max_reg_num ();
@@ -5590,23 +5591,13 @@ recompute_reg_usage (f, loop_step)
   /* Scan each insn in the chain and count how many times each register is
      set/used.  */
   loop_depth = 1;
-  for (insn = f; insn; insn = NEXT_INSN (insn))
+  for (index = 0; index < n_basic_blocks; index++)
     {
-      /* Keep track of loop depth.  */
-      if (GET_CODE (insn) == NOTE)
+      basic_block bb = BASIC_BLOCK (index);
+      loop_depth = bb->loop_depth;
+      for (insn = bb->head; insn; insn = NEXT_INSN (insn))
  	{
-	  /* Look for loop boundaries.  */
-	  if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_END)
-	    loop_depth -= loop_step;
-	  else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_BEG)
-	    loop_depth += loop_step;
-
-	  /* If we have LOOP_DEPTH == 0, there has been a bookkeeping error. 
-	     Abort now rather than setting register status incorrectly.  */
-	  if (loop_depth == 0)
-	    abort ();
-	}
-      else if (GET_RTX_CLASS (GET_CODE (insn)) == 'i')
+	  if (GET_RTX_CLASS (GET_CODE (insn)) == 'i')
 	    {
 	      rtx links;
 
@@ -5643,6 +5634,9 @@ recompute_reg_usage (f, loop_step)
 		      count_reg_references (XEXP (XEXP (note, 0), 0));
 		}
 	    }
+	  if (insn == bb->end)
+	    break;
+	}
     }
 }