predict.c (estimate_probability): Avoid duplicated predictions.

	* predict.c (estimate_probability): Avoid duplicated predictions.

	* loop.c (find_and_verify_loops): Grok multiple barriers.

From-SVN: r44369

gcc/ChangeLog

+Thu Jul 26 00:19:30 CEST 2001  Jan Hubicka  <jh@suse.cz>
+
+	* predict.c (estimate_probability): Avoid duplicated predictions.
+
+	* loop.c (find_and_verify_loops): Grok multiple barriers.
+
 Wed Jul 25 18:00:05 2001  Richard Kenner  <kenner@vlsi1.ultra.nyu.edu>
 
 	* config/alpha/alpha.c (print_operand, case '/'): Don't write '/'.

gcc/loop.c

@@ -2676,6 +2676,14 @@ find_and_verify_loops (f, loops)
 		  = JUMP_LABEL (insn) ? JUMP_LABEL (insn) : get_last_insn ();
 		struct loop *target_loop = uid_loop[INSN_UID (target)];
 		rtx loc, loc2;
+		rtx tmp;
+
+		/* Search for possible garbage past the conditional jumps
+		   and look for latest barrier.  */
+		for (tmp = last_insn_to_move;
+		     tmp && GET_CODE (tmp) != CODE_LABEL; tmp = NEXT_INSN (tmp))
+		  if (GET_CODE (tmp) == BARRIER)
+		    last_insn_to_move = tmp;
 
 		for (loc = target; loc; loc = PREV_INSN (loc))
 		  if (GET_CODE (loc) == BARRIER

gcc/predict.c

@@ -255,6 +255,7 @@ estimate_probability (loops_info)
 {
   sbitmap *dominators, *post_dominators;
   int i;
+  int found_noreturn = 0;
 
   dominators = sbitmap_vector_alloc (n_basic_blocks, n_basic_blocks);
   post_dominators = sbitmap_vector_alloc (n_basic_blocks, n_basic_blocks);
@@ -309,9 +310,15 @@ estimate_probability (loops_info)
       /* If block has no sucessor, predict all possible paths to
          it as improbable, as the block contains a call to a noreturn
 	 function and thus can be executed only once.  */
-      if (bb->succ == NULL)
+      if (bb->succ == NULL && !found_noreturn)
 	{
 	  int y;
+
+	  /* ??? Postdominator claims each noreturn block to be postdominated
+	     by each, so we need to run only once.  This needs to be changed
+	     once postdominace algorithm is updated to say something more sane.
+	     */
+	  found_noreturn = 1;
 	  for (y = 0; y < n_basic_blocks; y++)
 	    if (!TEST_BIT (post_dominators[y], i))
 	      {