re PR bootstrap/52287 (ICE in ready_remove_first, at haifa-sched.c:1927)

	PR bootstrap/52287
	* haifa-sched.c (rank_for_schedule): Stabilize sort for debug insns.

From-SVN: r184531

gcc/ChangeLog

+2012-02-23  Eric Botcazou  <ebotcazou@adacore.com>
+
+	PR bootstrap/52287
+	* haifa-sched.c (rank_for_schedule): Stabilize sort for debug insns.
+
 2012-02-23  Uros Bizjak  <ubizjak@gmail.com>
 
 	PR c/52290

gcc/haifa-sched.c

@@ -1647,8 +1647,10 @@ rank_for_schedule (const void *x, const void *y)
       /* Schedule debug insns as early as possible.  */
       if (DEBUG_INSN_P (tmp) && !DEBUG_INSN_P (tmp2))
 	return -1;
-      else if (DEBUG_INSN_P (tmp2))
+      else if (!DEBUG_INSN_P (tmp) && DEBUG_INSN_P (tmp2))
 	return 1;
+      else if (DEBUG_INSN_P (tmp) && DEBUG_INSN_P (tmp2))
+	return INSN_LUID (tmp) - INSN_LUID (tmp2);
     }
 
   /* The insn in a schedule group should be issued the first.  */