re PR rtl-optimization/14669 (Wrong code with -O for enum values expression E4 <= t && t <= E6)

2004-03-23  Kazu Hirata  <kazu@cs.umass.edu>

	PR optimization/14669
	* fold-const.c (fold): Only unwiden integer comparisons for equality
	or inequality operators, or when the signedness is the same.

	* g++.dg/opt/fold2.C: New test case.

From-SVN: r79859

gcc/ChangeLog

+2004-03-23  Kazu Hirata  <kazu@cs.umass.edu>
+
+	PR optimization/14669
+	* fold-const.c (fold): Only unwiden integer comparisons for equality
+	and inequality operators, or when the signedness doesn't change.
+
 2004-03-23  Jakub Jelinek  <jakub@redhat.com>
 
 	* config.gcc (sparc-*-linux*): Add sparc/t-linux to tmake_file.

gcc/fold-const.c

@@ -7535,6 +7535,9 @@ fold (tree expr)
       else if (TREE_CODE (TREE_TYPE (arg0)) == INTEGER_TYPE
 	       && TREE_CODE (arg0) == NOP_EXPR
 	       && (tem = get_unwidened (arg0, NULL_TREE)) != arg0
+	       && (code == EQ_EXPR || code == NE_EXPR
+		   || TREE_UNSIGNED (TREE_TYPE (arg0))
+		      == TREE_UNSIGNED (TREE_TYPE (tem)))
 	       && (t1 = get_unwidened (arg1, TREE_TYPE (tem))) != 0
 	       && (TREE_TYPE (t1) == TREE_TYPE (tem)
 		   || (TREE_CODE (t1) == INTEGER_CST

gcc/testsuite/ChangeLog

+2004-03-23  Roger Sayle  <roger@eyesopen.com>
+
+	PR optimization/14669
+	* g++.dg/opt/fold2.C: New test case.
+
 2004-03-22  Jakub Jelinek  <jakub@redhat.com>
 
 	PR c/14069

gcc/testsuite/g++.dg/opt/fold2.C

+// PR optimization/14669
+// { dg-do run }
+// { dg-options "-O2" }
+
+extern "C" void abort (void);
+extern "C" void exit (int);
+
+enum ActionType { EE=-1, E0=0, E1, E2 };
+
+int main(void)
+{
+  ActionType t = E0;
+
+  if (E1 <= t && t <= E2)
+    abort ();
+
+  exit (0);
+}
+