[backport from gcc-4.7/trunk, fixes regression from PR44374 patch <mikpe@it.uu.se>]

gcc/

2011-03-20  Jakub Jelinek  <jakub@redhat.com>

	PR rtl-optimization/48156
	* df-core.c (df_get_bb_dirty): Use df_lr if df_live is NULL,
	assume df and df_lr are not NULL.

gcc/testsuite/

2011-03-20  Jakub Jelinek  <jakub@redhat.com>

	PR rtl-optimization/48156
	* gcc.dg/pr48156.c: New test.

--- gcc-4.6-20110318/gcc/df-core.c.~1~	2010-12-14 01:23:40.000000000 +0100
+++ gcc-4.6-20110318/gcc/df-core.c	2011-03-21 14:50:32.000000000 +0100
@@ -1,6 +1,6 @@
 /* Allocation for dataflow support routines.
    Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
-   2008, 2009, 2010 Free Software Foundation, Inc.
+   2008, 2009, 2010, 2011 Free Software Foundation, Inc.
    Originally contributed by Michael P. Hayes
              (m.hayes@elec.canterbury.ac.nz, mhayes@redhat.com)
    Major rewrite contributed by Danny Berlin (dberlin@dberlin.org)
@@ -1400,10 +1400,9 @@ df_mark_solutions_dirty (void)
 bool
 df_get_bb_dirty (basic_block bb)
 {
-  if (df && df_live)
-    return bitmap_bit_p (df_live->out_of_date_transfer_functions, bb->index);
-  else
-    return false;
+  return bitmap_bit_p ((df_live
+			? df_live : df_lr)->out_of_date_transfer_functions,
+		       bb->index);
 }
 
 
--- gcc-4.6-20110318/gcc/testsuite/gcc.dg/pr48156.c.~1~	1970-01-01 01:00:00.000000000 +0100
+++ gcc-4.6-20110318/gcc/testsuite/gcc.dg/pr48156.c	2011-03-21 14:50:32.000000000 +0100
@@ -0,0 +1,45 @@
+/* PR rtl-optimization/48156 */
+/* { dg-do run } */
+/* { dg-options "-O -fcrossjumping --param min-crossjump-insns=1" } */
+
+extern void abort (void);
+
+static int __attribute__ ((noinline, noclone))
+equals (int s1, int s2)
+{
+  return s1 == s2;
+}
+
+static int __attribute__ ((noinline, noclone))
+bar (void)
+{
+  return 1;
+}
+
+static void __attribute__ ((noinline, noclone))
+baz (int f, int j)
+{
+  if (f != 4 || j != 2)
+    abort ();
+}
+
+void
+foo (int x)
+{
+  int i = 0, j = bar ();
+
+  if (x == 1)
+    i = 2;
+
+  if (j && equals (i, j))
+    baz (8, i);
+  else
+    baz (4, i);
+}
+
+int
+main ()
+{
+  foo (1);
+  return 0;
+}