re PR middle-end/42716 (ICE in extract_range_from_assert, at tree-vrp.c:1423)

2010-01-13  Richard Guenther  <rguenther@suse.de>

	PR middle-end/42716
	* fold-const.c (fold_unary_loc): Fold INDIRECT_REFs.

	* gcc.c-torture/compile/pr42716.c: New testcase.

From-SVN: r155859

gcc/ChangeLog

+2010-01-13  Richard Guenther  <rguenther@suse.de>
+
+	PR middle-end/42716
+	* fold-const.c (fold_unary_loc): Fold INDIRECT_REFs.
+
 2010-01-13  Jakub Jelinek  <jakub@redhat.com>
 
 	PR debug/41371

gcc/fold-const.c

@@ -8942,6 +8942,19 @@ fold_unary_loc (location_t loc, enum tree_code code, tree type, tree op0)
 	}
       return NULL_TREE;
 
+    case INDIRECT_REF:
+      /* Fold *&X to X if X is an lvalue.  */
+      if (TREE_CODE (op0) == ADDR_EXPR)
+	{
+	  tree op00 = TREE_OPERAND (op0, 0);
+	  if ((TREE_CODE (op00) == VAR_DECL
+	       || TREE_CODE (op00) == PARM_DECL
+	       || TREE_CODE (op00) == RESULT_DECL)
+	      && !TREE_READONLY (op00))
+	    return op00;
+	}
+      return NULL_TREE;
+
     default:
       return NULL_TREE;
     } /* switch (code) */

gcc/testsuite/ChangeLog

 2010-01-13  Richard Guenther  <rguenther@suse.de>
 
+	PR middle-end/42716
+	* gcc.c-torture/compile/pr42716.c: New testcase.
+
+2010-01-13  Richard Guenther  <rguenther@suse.de>
+
 	PR lto/42678
 	* gfortran.dg/lto/20100110-1_0.f90: New testcase.
 

gcc/testsuite/gcc.c-torture/compile/pr42716.c

+static short foo (long long si1, short si2)
+{
+  return si1 > 0 && si2 > 0 || si1 < 0
+      && si2 < 0 && si1 < 1 - si2 ? : si1 + si2;
+}
+
+int g_13;
+unsigned g_17;
+
+int safe (int, int);
+
+void bar (short p_51, short * p_52)
+{
+  int *const l_55 = &g_13;
+  if (safe (*p_52, g_13 != foo (*p_52 & *l_55 == g_13 && g_17 >= 1, 0)))
+    {
+    }
+}