re PR rtl-optimization/49941 (segmentation fault in redirect_jump_2)

	PR rtl-optimization/49941
	* jump.c (mark_jump_label): Comment.
	(mark_jump_label_1): Set JUMP_LABEL for return jumps.
	* emit-rtl.c (copy_rtx_if_shared_1, copy_insn_1): Leave RETURN shared.
	(mark_used_flags): Don't mark RETURN.

From-SVN: r177268

gcc/ChangeLog

+2011-08-03  Alan Modra  <amodra@gmail.com>
+
+	PR rtl-optimization/49941
+	* jump.c (mark_jump_label): Comment.
+	(mark_jump_label_1): Set JUMP_LABEL for return jumps.
+	* emit-rtl.c (copy_rtx_if_shared_1, copy_insn_1): Leave RETURN shared.
+	(mark_used_flags): Don't mark RETURN.
+
 2011-08-03  Richard Guenther  <rguenther@suse.de>
 
 	PR tree-optimization/49938
@@ -176,10 +184,10 @@
 	boolean-typed operands for comparisons.
 
 2011-08-02  Georg-Johann Lay  <avr@gjlay.de>
-	
+
 	* config/avr/libgcc.S: Gather related function in the
 	same input section.
- 	(__mulqihi3, __mulqihi3, __divmodqi4, __divmodhi4, __udivmodsi4,
+	(__mulqihi3, __mulqihi3, __divmodqi4, __divmodhi4, __udivmodsi4,
 	__divmodsi4): Use XCALL/XJMP instead of rcall/rjmp for external
 	references.
 	(__udivmodqi4, __divmodqi4, __udivmodhi4, __divmodhi4,
@@ -21337,7 +21345,7 @@
 	to cselib_lookup.
 	(add_uses): Likewise, also to cselib_subst_to_values.
 	(add_stores): Likewise.
-	* sched-deps.c 	(add_insn_mem_dependence): Pass mode to
+	* sched-deps.c (add_insn_mem_dependence): Pass mode to
 	cselib_subst_to_values.
 	(sched_analyze_1, sched_analyze_2): Likewise.  Adjusted.
 	* gcse.c (do_local_cprop): Adjusted.

gcc/emit-rtl.c

@@ -2724,6 +2724,7 @@ repeat:
     case CODE_LABEL:
     case PC:
     case CC0:
+    case RETURN:
     case SCRATCH:
       /* SCRATCH must be shared because they represent distinct values.  */
       return;
@@ -2843,6 +2844,7 @@ repeat:
     case CODE_LABEL:
     case PC:
     case CC0:
+    case RETURN:
       return;
 
     case DEBUG_INSN:
@@ -5261,6 +5263,7 @@ copy_insn_1 (rtx orig)
     case CODE_LABEL:
     case PC:
     case CC0:
+    case RETURN:
       return orig;
     case CLOBBER:
       if (REG_P (XEXP (orig, 0)) && REGNO (XEXP (orig, 0)) < FIRST_PSEUDO_REGISTER)

gcc/jump.c

 /* Optimize jump instructions, for GNU compiler.
    Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997
-   1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2010
-   Free Software Foundation, Inc.
+   1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2010,
+   2011 Free Software Foundation, Inc.
 
 This file is part of GCC.
 
@@ -1039,6 +1039,7 @@ sets_cc0_p (const_rtx x)
    notes.  If INSN is an INSN or a CALL_INSN or non-target operands of
    a JUMP_INSN, and there is at least one CODE_LABEL referenced in
    INSN, add a REG_LABEL_OPERAND note containing that label to INSN.
+   For returnjumps, the JUMP_LABEL will also be set as appropriate.
 
    Note that two labels separated by a loop-beginning note
    must be kept distinct if we have not yet done loop-optimization,
@@ -1081,6 +1082,14 @@ mark_jump_label_1 (rtx x, rtx insn, bool in_mem, bool is_target)
     case CALL:
       return;
 
+    case RETURN:
+      if (is_target)
+	{
+	  gcc_assert (JUMP_LABEL (insn) == NULL || JUMP_LABEL (insn) == x);
+	  JUMP_LABEL (insn) = x;
+	}
+      return;
+
     case MEM:
       in_mem = true;
       break;