* jump.c (redirect_jump): Add delete_unused argument. Don't

        remove labels and code following when LABEL_NUSES goes to zero.
        (invert_jump): Likewise.
        (jump_optimize_1): Fix redirect/invert arguments.
        (do_cross_jump, thread_jumps): Likewise.
        * flow.c (split_edge): Likewise.
        * reorg.c (optimize_skip): Likewise.
        (reorg_redirect_jump, relax_delay_slots, dbr_schedule): Likewise.
        * profile.c (instrument_arcs): Likewise.
        * loop.c (find_and_verify_loops): Likewise.  Fix indentation.
        * rtl.h: Update prototypes.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@34033 138bc75d-0d04-0410-961f-82ee72b054a4

7 files changed, 118 insertions, 110 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 54e7627562f..0ba93a4ef57 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,17 @@
+2000-05-19  Richard Henderson  <rth@cygnus.com>
+
+	* jump.c (redirect_jump): Add delete_unused argument.  Don't
+	remove labels and code following when LABEL_NUSES goes to zero.
+	(invert_jump): Likewise.
+	(jump_optimize_1): Fix redirect/invert arguments.
+	(do_cross_jump, thread_jumps): Likewise.
+	* flow.c (split_edge): Likewise.
+	* reorg.c (optimize_skip): Likewise.
+	(reorg_redirect_jump, relax_delay_slots, dbr_schedule): Likewise.
+	* profile.c (instrument_arcs): Likewise.
+	* loop.c (find_and_verify_loops): Likewise.  Fix indentation.
+	* rtl.h: Update prototypes.
+
 Fri May 19 12:05:13 2000  Clinton Popetz  <cpopetz@cygnus.com>
 
 	* ssa.c (convert_from_ssa): Tell life_analysis we need death 
@@ -52,7 +66,7 @@ Fri May 19 06:49:35 2000  Richard Kenner  <kenner@vlsi1.ultra.nyu.edu>
 
 2000-05-18 Mark Elbrecht <snowball3@bigfoot.com>
 
-        * configure.in (*-pc-msdosdjgpp): Set float_format to none.
+	* configure.in (*-pc-msdosdjgpp): Set float_format to none.
 	* configure: Rebuilt.
 
 2000-05-18  Zack Weinberg  <zack@wolery.cumb.org>
diff --git a/gcc/flow.c b/gcc/flow.c
index e24822e8404..e6d4bbbcbfa 100644
--- a/gcc/flow.c
+++ b/gcc/flow.c
@@ -1556,7 +1556,7 @@ split_edge (edge_in)
 	  if (JUMP_LABEL (insn) != old_label)
 	    abort ();
 
-	  redirect_jump (insn, new_label);
+	  redirect_jump (insn, new_label, 0);
 	}
 
       emit_label_before (new_label, bb_note);
diff --git a/gcc/jump.c b/gcc/jump.c
index 85bfb86a500..8711ba95efd 100644
--- a/gcc/jump.c
+++ b/gcc/jump.c
@@ -342,7 +342,7 @@ jump_optimize_1 (f, cross_jump, noop_moves, after_regscan,
 	  /* See if this jump goes to another jump and redirect if so.  */
 	  nlabel = follow_jumps (JUMP_LABEL (insn));
 	  if (nlabel != JUMP_LABEL (insn))
-	    changed |= redirect_jump (insn, nlabel);
+	    changed |= redirect_jump (insn, nlabel, 1);
 
 	  if (! optimize || minimal)
 	    continue;
@@ -444,7 +444,7 @@ jump_optimize_1 (f, cross_jump, noop_moves, after_regscan,
 	      if (prev_label)
 		++LABEL_NUSES (prev_label);
 
-	      if (invert_jump (insn, JUMP_LABEL (reallabelprev)))
+	      if (invert_jump (insn, JUMP_LABEL (reallabelprev), 1))
 		{
 		  /* It is very likely that if there are USE insns before
 		     this jump, they hold REG_DEAD notes.  These REG_DEAD
@@ -507,7 +507,7 @@ jump_optimize_1 (f, cross_jump, noop_moves, after_regscan,
 		}
 
 	      delete_insn (temp);
-	      redirect_jump (insn, get_label_before (temp1));
+	      redirect_jump (insn, get_label_before (temp1), 1);
 	      reallabelprev = prev_real_insn (temp1);
 	      changed = 1;
 	      next = NEXT_INSN (insn);
@@ -579,7 +579,7 @@ jump_optimize_1 (f, cross_jump, noop_moves, after_regscan,
 		       && swap_condition (GET_CODE (temp2)) == GET_CODE (tc)
 		       && rtx_equal_p (XEXP (tc, 0), XEXP (temp2, 0))
 		       && rtx_equal_p (XEXP (tc, 1), XEXP (temp2, 1))
-		       && redirect_jump (insn, get_label_after (temp)))
+		       && redirect_jump (insn, get_label_after (temp), 1))
 		{
 		  changed = 1;
 		  continue;
@@ -1629,7 +1629,7 @@ do_cross_jump (insn, newjpos, newlpos)
 	}
     }
   else
-    redirect_jump (insn, label);
+    redirect_jump (insn, label, 1);
 
   /* Delete the matching insns before the jump.  Also, remove any REG_EQUAL
      or REG_EQUIV note in the NEWLPOS stream that isn't also present in
@@ -3182,8 +3182,9 @@ redirect_jump_1 (jump, nlabel)
    (this can only occur for NLABEL == 0).  */
 
 int
-redirect_jump (jump, nlabel)
+redirect_jump (jump, nlabel, delete_unused)
      rtx jump, nlabel;
+     int delete_unused;
 {
   register rtx olabel = JUMP_LABEL (jump);
 
@@ -3221,7 +3222,7 @@ redirect_jump (jump, nlabel)
       && NOTE_LINE_NUMBER (NEXT_INSN (olabel)) == NOTE_INSN_FUNCTION_END)
     emit_note_after (NOTE_INSN_FUNCTION_END, nlabel);
 
-  if (olabel && --LABEL_NUSES (olabel) == 0)
+  if (olabel && --LABEL_NUSES (olabel) == 0 && delete_unused)
     delete_insn (olabel);
 
   return 1;
@@ -3321,8 +3322,9 @@ invert_jump_1 (jump, nlabel)
    NLABEL instead of where it jumps now.  Return true if successful.  */
 
 int
-invert_jump (jump, nlabel)
+invert_jump (jump, nlabel, delete_unused)
      rtx jump, nlabel;
+     int delete_unused;
 {
   /* We have to either invert the condition and change the label or
      do neither.  Either operation could fail.  We first try to invert
@@ -3332,7 +3334,7 @@ invert_jump (jump, nlabel)
   if (! invert_exp (PATTERN (jump), jump))
     return 0;
 
-  if (redirect_jump (jump, nlabel))
+  if (redirect_jump (jump, nlabel, delete_unused))
     {
       /* An inverted jump means that a probability taken becomes a
 	 probability not taken.  Subtract the branch probability from the
@@ -3911,7 +3913,7 @@ thread_jumps (f, max_reg, flag_before_loop)
 			      new_label = gen_label_rtx ();
 			      emit_label_after (new_label, PREV_INSN (prev));
 			    }
-			  changed |= redirect_jump (b1, new_label);
+			  changed |= redirect_jump (b1, new_label, 1);
 			}
 		      break;
 		    }
diff --git a/gcc/loop.c b/gcc/loop.c
index 70c307ab82c..a8e71b71545 100644
--- a/gcc/loop.c
+++ b/gcc/loop.c
@@ -2865,86 +2865,86 @@ find_and_verify_loops (f, loops)
 
 		    /* Verify that uid_loop is large enough and that
 		       we can invert P.  */
-		   if (invert_jump (p, new_label))
-		     {
-		       rtx q, r;
-
-		       /* If no suitable BARRIER was found, create a suitable
-			  one before TARGET.  Since TARGET is a fall through
-			  path, we'll need to insert an jump around our block
-			  and a add a BARRIER before TARGET.
-
-			  This creates an extra unconditional jump outside
-			  the loop.  However, the benefits of removing rarely
-			  executed instructions from inside the loop usually
-			  outweighs the cost of the extra unconditional jump
-			  outside the loop.  */
-		       if (loc == 0)
-			 {
-			   rtx temp;
-
-		           temp = gen_jump (JUMP_LABEL (insn));
-			   temp = emit_jump_insn_before (temp, target);
-			   JUMP_LABEL (temp) = JUMP_LABEL (insn);
-			   LABEL_NUSES (JUMP_LABEL (insn))++;
-			   loc = emit_barrier_before (target);
-			 }
-
-		       /* Include the BARRIER after INSN and copy the
-			  block after LOC.  */
-		       new_label = squeeze_notes (new_label, 
-						  last_insn_to_move);
-		       reorder_insns (new_label, last_insn_to_move, loc);
-
-		       /* All those insns are now in TARGET_LOOP.  */
-		       for (q = new_label; 
-			    q != NEXT_INSN (last_insn_to_move);
-			    q = NEXT_INSN (q))
-			 uid_loop[INSN_UID (q)] = target_loop;
-
-		       /* The label jumped to by INSN is no longer a loop exit.
-			  Unless INSN does not have a label (e.g., it is a
-			  RETURN insn), search loop->exit_labels to find
-			  its label_ref, and remove it.  Also turn off
-			  LABEL_OUTSIDE_LOOP_P bit.  */
-		       if (JUMP_LABEL (insn))
-			 {
-			   for (q = 0,
-				r = this_loop->exit_labels;
-				r; q = r, r = LABEL_NEXTREF (r))
-			     if (XEXP (r, 0) == JUMP_LABEL (insn))
-			       {
-				 LABEL_OUTSIDE_LOOP_P (r) = 0;
-				 if (q)
-				   LABEL_NEXTREF (q) = LABEL_NEXTREF (r);
-				 else
-				   this_loop->exit_labels = LABEL_NEXTREF (r);
-				 break;
-			       }
-
-			   for (loop = this_loop; loop && loop != target_loop;
-				loop = loop->outer)
-			     loop->exit_count--;
-
-			   /* If we didn't find it, then something is
-                              wrong.  */
-			   if (! r)
-			     abort ();
-			 }
-
-		       /* P is now a jump outside the loop, so it must be put
-			  in loop->exit_labels, and marked as such.
-			  The easiest way to do this is to just call
-			  mark_loop_jump again for P.  */
-		       mark_loop_jump (PATTERN (p), this_loop);
-
-		       /* If INSN now jumps to the insn after it,
-			  delete INSN.  */
-		       if (JUMP_LABEL (insn) != 0
-			   && (next_real_insn (JUMP_LABEL (insn))
-			       == next_real_insn (insn)))
-			 delete_insn (insn);
-		     }
+		    if (invert_jump (p, new_label, 1))
+		      {
+			rtx q, r;
+
+			/* If no suitable BARRIER was found, create a suitable
+			   one before TARGET.  Since TARGET is a fall through
+			   path, we'll need to insert an jump around our block
+			   and a add a BARRIER before TARGET.
+
+			   This creates an extra unconditional jump outside
+			   the loop.  However, the benefits of removing rarely
+			   executed instructions from inside the loop usually
+			   outweighs the cost of the extra unconditional jump
+			   outside the loop.  */
+			if (loc == 0)
+			  {
+			    rtx temp;
+
+			    temp = gen_jump (JUMP_LABEL (insn));
+			    temp = emit_jump_insn_before (temp, target);
+			    JUMP_LABEL (temp) = JUMP_LABEL (insn);
+			    LABEL_NUSES (JUMP_LABEL (insn))++;
+			    loc = emit_barrier_before (target);
+			  }
+
+			/* Include the BARRIER after INSN and copy the
+			   block after LOC.  */
+			new_label = squeeze_notes (new_label, 
+						   last_insn_to_move);
+			reorder_insns (new_label, last_insn_to_move, loc);
+
+			/* All those insns are now in TARGET_LOOP.  */
+			for (q = new_label; 
+			     q != NEXT_INSN (last_insn_to_move);
+			     q = NEXT_INSN (q))
+			  uid_loop[INSN_UID (q)] = target_loop;
+
+			/* The label jumped to by INSN is no longer a loop
+			   exit.  Unless INSN does not have a label (e.g.,
+			   it is a RETURN insn), search loop->exit_labels
+			   to find its label_ref, and remove it.  Also turn
+			   off LABEL_OUTSIDE_LOOP_P bit.  */
+			if (JUMP_LABEL (insn))
+			  {
+			    for (q = 0,
+				   r = this_loop->exit_labels;
+				 r; q = r, r = LABEL_NEXTREF (r))
+			      if (XEXP (r, 0) == JUMP_LABEL (insn))
+				{
+				  LABEL_OUTSIDE_LOOP_P (r) = 0;
+				  if (q)
+				    LABEL_NEXTREF (q) = LABEL_NEXTREF (r);
+				  else
+				    this_loop->exit_labels = LABEL_NEXTREF (r);
+				  break;
+				}
+
+			    for (loop = this_loop; loop && loop != target_loop;
+				 loop = loop->outer)
+			      loop->exit_count--;
+
+			    /* If we didn't find it, then something is
+			       wrong.  */
+			    if (! r)
+			      abort ();
+			  }
+
+			/* P is now a jump outside the loop, so it must be put
+			   in loop->exit_labels, and marked as such.
+			   The easiest way to do this is to just call
+			   mark_loop_jump again for P.  */
+			mark_loop_jump (PATTERN (p), this_loop);
+
+			/* If INSN now jumps to the insn after it,
+			   delete INSN.  */
+			if (JUMP_LABEL (insn) != 0
+			    && (next_real_insn (JUMP_LABEL (insn))
+				== next_real_insn (insn)))
+			  delete_insn (insn);
+		      }
 
 		    /* Continue the loop after where the conditional
 		       branch used to jump, since the only branch insn
diff --git a/gcc/profile.c b/gcc/profile.c
index d8e2d62e62a..69ac575168d 100644
--- a/gcc/profile.c
+++ b/gcc/profile.c
@@ -293,14 +293,14 @@ instrument_arcs (f, num_blocks, dump_file)
 		  if (this_is_simplejump)
 		    {
 		      after = NEXT_INSN (arcptr->branch_insn);
-		      if (! redirect_jump (arcptr->branch_insn, new_label))
+		      if (! redirect_jump (arcptr->branch_insn, new_label, 1))
 			/* Don't know what to do if this branch won't
 			   redirect.  */
 			abort ();
 		    }
 		  else
 		    {
-		      if (! invert_jump (arcptr->branch_insn, new_label))
+		      if (! invert_jump (arcptr->branch_insn, new_label, 1))
 			/* Don't know what to do if this branch won't invert.  */
 			abort ();
 
diff --git a/gcc/reorg.c b/gcc/reorg.c
index cce40c0d7cf..e5c58873aa2 100644
--- a/gcc/reorg.c
+++ b/gcc/reorg.c
@@ -733,7 +733,7 @@ optimize_skip (insn)
     {
       if (eligible_for_annul_false (insn, 0, trial, flags))
 	{
-	  if (invert_jump (insn, JUMP_LABEL (insn)))
+	  if (invert_jump (insn, JUMP_LABEL (insn), 1))
 	    INSN_FROM_TARGET_P (trial) = 1;
 	  else if (! eligible_for_annul_true (insn, 0, trial, flags))
 	    return 0;
@@ -1888,7 +1888,7 @@ reorg_redirect_jump (jump, nlabel)
      rtx nlabel;
 {
   incr_ticks_for_insn (jump);
-  return redirect_jump (jump, nlabel);
+  return redirect_jump (jump, nlabel, 1);
 }
 
 /* Called when INSN is being moved forward into a delay slot of DELAYED_INSN.
@@ -3087,7 +3087,7 @@ relax_delay_slots (first)
 	      if (label)
 		++LABEL_NUSES (label);
 
-	      if (invert_jump (insn, label))
+	      if (invert_jump (insn, label, 1))
 		{
 		  delete_insn (next);
 		  next = insn;
@@ -3123,16 +3123,8 @@ relax_delay_slots (first)
 	  rtx other_target = JUMP_LABEL (other);
 	  target_label = JUMP_LABEL (insn);
 
-	  /* Increment the count of OTHER_TARGET, so it doesn't get deleted
-	     as we move the label.  */
-	  if (other_target)
-	    ++LABEL_NUSES (other_target);
-
-	  if (invert_jump (other, target_label))
+	  if (invert_jump (other, target_label, 0))
 	    reorg_redirect_jump (insn, other_target);
-
-	  if (other_target)
-	    --LABEL_NUSES (other_target);
 	}
 
       /* Now look only at cases where we have filled a delay slot.  */
@@ -3338,7 +3330,7 @@ relax_delay_slots (first)
 	      if (old_label)
 		++LABEL_NUSES (old_label);
 
-	      if (invert_jump (delay_insn, label))
+	      if (invert_jump (delay_insn, label, 1))
 		{
 		  int i;
 
@@ -3570,7 +3562,7 @@ dbr_schedule (first, file)
 	  && JUMP_LABEL (insn) != 0
 	  && ((target = prev_label (next_active_insn (JUMP_LABEL (insn))))
 	      != JUMP_LABEL (insn)))
-	redirect_jump (insn, target);
+	redirect_jump (insn, target, 1);
     }
 
   init_resource_info (epilogue_insn);
diff --git a/gcc/rtl.h b/gcc/rtl.h
index 4ab7407f335..de088179e52 100644
--- a/gcc/rtl.h
+++ b/gcc/rtl.h
@@ -1522,11 +1522,11 @@ extern int returnjump_p			PARAMS ((rtx));
 extern int onlyjump_p			PARAMS ((rtx));
 extern int sets_cc0_p			PARAMS ((rtx));
 extern int invert_jump_1		PARAMS ((rtx, rtx));
-extern int invert_jump			PARAMS ((rtx, rtx));
+extern int invert_jump			PARAMS ((rtx, rtx, int));
 extern int rtx_renumbered_equal_p	PARAMS ((rtx, rtx));
 extern int true_regnum			PARAMS ((rtx));
 extern int redirect_jump_1		PARAMS ((rtx, rtx));
-extern int redirect_jump		PARAMS ((rtx, rtx));
+extern int redirect_jump		PARAMS ((rtx, rtx, int));
 extern void jump_optimize		PARAMS ((rtx, int, int, int));
 extern void jump_optimize_minimal	PARAMS ((rtx));
 extern void rebuild_jump_labels		PARAMS ((rtx));