From: Jakub Jelinek <jakub@redhat.com>
Date: Wed, 15 Jul 2009 10:17:54 +0000 (+0200)
Subject: re PR middle-end/40747 (wrong code for int-is-in-range test at -O1 and above)
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=b4e4232dc53bbe172d5a7f2a4df972846d8508c6;p=gcc.git

re PR middle-end/40747 (wrong code for int-is-in-range test at -O1 and above)

	PR middle-end/40747
	* fold-const.c (fold_cond_expr_with_comparison): When folding
	< and <= to MIN, make sure the MIN uses the same type as the
	comparison's operands.

	* gcc.c-torture/execute/pr40747.c: New test.

From-SVN: r149675
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 8ae44d8bdb6..d68d157212b 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,10 @@
+2009-07-15  Jakub Jelinek  <jakub@redhat.com>
+
+	PR middle-end/40747
+	* fold-const.c (fold_cond_expr_with_comparison): When folding
+	< and <= to MIN, make sure the MIN uses the same type as the
+	comparison's operands.
+
 2009-07-15  Richard Earnshaw  <rearnsha@arm.com>
 
 	* arm.md (ior_xor): New code iterator.
diff --git a/gcc/fold-const.c b/gcc/fold-const.c
index f3e0614a4a6..eba869085cc 100644
--- a/gcc/fold-const.c
+++ b/gcc/fold-const.c
@@ -5310,31 +5310,35 @@ fold_cond_expr_with_comparison (tree type, tree arg0, tree arg1, tree arg2)
 	return fold_build3 (COND_EXPR, type, arg0, arg1, arg2);
 
       case LT_EXPR:
-	/* If C1 is C2 + 1, this is min(A, C2).  */
+	/* If C1 is C2 + 1, this is min(A, C2), but use ARG00's type for
+	   MIN_EXPR, to preserve the signedness of the comparison.  */
 	if (! operand_equal_p (arg2, TYPE_MAX_VALUE (type),
 			       OEP_ONLY_CONST)
 	    && operand_equal_p (arg01,
 				const_binop (PLUS_EXPR, arg2,
 					     build_int_cst (type, 1), 0),
 				OEP_ONLY_CONST))
-	  return pedantic_non_lvalue (fold_build2 (MIN_EXPR,
-						   type,
-						   fold_convert (type, arg1),
-						   arg2));
+	  {
+	    tem = fold_build2 (MIN_EXPR, TREE_TYPE (arg00), arg00,
+			       fold_convert (TREE_TYPE (arg00), arg2));
+	    return pedantic_non_lvalue (fold_convert (type, tem));
+	  }
 	break;
 
       case LE_EXPR:
-	/* If C1 is C2 - 1, this is min(A, C2).  */
+	/* If C1 is C2 - 1, this is min(A, C2), with the same care
+	   as above.  */
 	if (! operand_equal_p (arg2, TYPE_MIN_VALUE (type),
 			       OEP_ONLY_CONST)
 	    && operand_equal_p (arg01,
 				const_binop (MINUS_EXPR, arg2,
 					     build_int_cst (type, 1), 0),
 				OEP_ONLY_CONST))
-	  return pedantic_non_lvalue (fold_build2 (MIN_EXPR,
-						   type,
-						   fold_convert (type, arg1),
-						   arg2));
+	  {
+	    tem = fold_build2 (MIN_EXPR, TREE_TYPE (arg00), arg00,
+			       fold_convert (TREE_TYPE (arg00), arg2));
+	    return pedantic_non_lvalue (fold_convert (type, tem));
+	  }
 	break;
 
       case GT_EXPR:
@@ -5346,11 +5350,11 @@ fold_cond_expr_with_comparison (tree type, tree arg0, tree arg1, tree arg2)
 				const_binop (MINUS_EXPR, arg2,
 					     build_int_cst (type, 1), 0),
 				OEP_ONLY_CONST))
-	  return pedantic_non_lvalue (fold_convert (type,
-				      fold_build2 (MAX_EXPR, TREE_TYPE (arg00),
-						   arg00,
-						   fold_convert (TREE_TYPE (arg00),
-							         arg2))));
+	  {
+	    tem = fold_build2 (MAX_EXPR, TREE_TYPE (arg00), arg00,
+			       fold_convert (TREE_TYPE (arg00), arg2));
+	    return pedantic_non_lvalue (fold_convert (type, tem));
+	  }
 	break;
 
       case GE_EXPR:
@@ -5361,11 +5365,11 @@ fold_cond_expr_with_comparison (tree type, tree arg0, tree arg1, tree arg2)
 				const_binop (PLUS_EXPR, arg2,
 					     build_int_cst (type, 1), 0),
 				OEP_ONLY_CONST))
-	  return pedantic_non_lvalue (fold_convert (type,
-				      fold_build2 (MAX_EXPR, TREE_TYPE (arg00),
-						   arg00,
-						   fold_convert (TREE_TYPE (arg00),
-							         arg2))));
+	  {
+	    tem = fold_build2 (MAX_EXPR, TREE_TYPE (arg00), arg00,
+			       fold_convert (TREE_TYPE (arg00), arg2));
+	    return pedantic_non_lvalue (fold_convert (type, tem));
+	  }
 	break;
       case NE_EXPR:
 	break;
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index e58a25b8822..6083654ab0b 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2009-07-15  Jakub Jelinek  <jakub@redhat.com>
+
+	PR middle-end/40747
+	* gcc.c-torture/execute/pr40747.c: New test.
+
 2009-07-15  Richard Guenther  <rguenther@suse.de>
 
 	PR middle-end/40753
diff --git a/gcc/testsuite/gcc.c-torture/execute/pr40747.c b/gcc/testsuite/gcc.c-torture/execute/pr40747.c
new file mode 100644
index 00000000000..1c75be3fcc5
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/execute/pr40747.c
@@ -0,0 +1,22 @@
+/* PR middle-end/40747 */
+
+extern void abort (void);
+
+int
+foo (int i)
+{
+  return (i < 4 && i >= 0) ? i : 4;
+}
+
+int
+main ()
+{
+  if (foo (-1) != 4) abort ();
+  if (foo (0) != 0) abort ();
+  if (foo (1) != 1) abort ();
+  if (foo (2) != 2) abort ();
+  if (foo (3) != 3) abort ();
+  if (foo (4) != 4) abort ();
+  if (foo (5) != 4) abort ();
+  return 0;
+}