diff mbox

Fix fold_binary_loc BIT_XOR_EXPR folding (PR sanitizer/80349)

Message ID 20170427191744.GE4255@redhat.com
State New
Headers show

Commit Message

Marek Polacek April 27, 2017, 7:17 p.m. UTC 
Yet another missing converts caused that BIT_XOR_EXPRs with incompatible
arguments have gotten into the gimplifier.  Fixed thus.  This patch also
improves readability by using a temporary, the current style wasn't very
readable especially because of the wrong formatting caused by adding the
*_loc variants...

Bootstrapped/regtested on x86_64-linux, ok for trunk?

2017-04-27  Marek Polacek  <polacek@redhat.com>

	PR sanitizer/80349
	* fold-const.c (fold_binary_loc) <case EQ_EXPR, NE_EXPR>: Convert
	arg10 and arg11 to itype.

	* c-c++-common/ubsan/pr80349.c: New test.


	Marek

Comments

Jakub Jelinek April 27, 2017, 8:58 p.m. UTC | #1 
On Thu, Apr 27, 2017 at 09:17:44PM +0200, Marek Polacek wrote:
> Yet another missing converts caused that BIT_XOR_EXPRs with incompatible
> arguments have gotten into the gimplifier.  Fixed thus.  This patch also
> improves readability by using a temporary, the current style wasn't very
> readable especially because of the wrong formatting caused by adding the
> *_loc variants...

Yeah, this is indeed much more readable.

> Bootstrapped/regtested on x86_64-linux, ok for trunk?
> 
> 2017-04-27  Marek Polacek  <polacek@redhat.com>
> 
> 	PR sanitizer/80349
> 	* fold-const.c (fold_binary_loc) <case EQ_EXPR, NE_EXPR>: Convert
> 	arg10 and arg11 to itype.
> 
> 	* c-c++-common/ubsan/pr80349.c: New test.

Ok for trunk and after a while for 7.2.

	Jakub
diff mbox

Patch

diff --git gcc/fold-const.c gcc/fold-const.c
index ce4b2df..f6d5af4 100644
--- gcc/fold-const.c
+++ gcc/fold-const.c
@@ -10797,40 +10797,37 @@  fold_binary_loc (location_t loc,
 	  tree itype = TREE_TYPE (arg0);
 
 	  if (operand_equal_p (arg01, arg11, 0))
-	    return fold_build2_loc (loc, code, type,
-				fold_build2_loc (loc, BIT_AND_EXPR, itype,
-					     fold_build2_loc (loc,
-							  BIT_XOR_EXPR, itype,
-							  arg00, arg10),
-					     arg01),
-				build_zero_cst (itype));
-
+	    {
+	      tem = fold_convert_loc (loc, itype, arg10);
+	      tem = fold_build2_loc (loc, BIT_XOR_EXPR, itype, arg00, tem);
+	      tem = fold_build2_loc (loc, BIT_AND_EXPR, itype, tem, arg01);
+	      return fold_build2_loc (loc, code, type, tem,
+				      build_zero_cst (itype));
+	    }
 	  if (operand_equal_p (arg01, arg10, 0))
-	    return fold_build2_loc (loc, code, type,
-				fold_build2_loc (loc, BIT_AND_EXPR, itype,
-					     fold_build2_loc (loc,
-							  BIT_XOR_EXPR, itype,
-							  arg00, arg11),
-					     arg01),
-				build_zero_cst (itype));
-
+	    {
+	      tem = fold_convert_loc (loc, itype, arg11);
+	      tem = fold_build2_loc (loc, BIT_XOR_EXPR, itype, arg00, tem);
+	      tem = fold_build2_loc (loc, BIT_AND_EXPR, itype, tem, arg01);
+	      return fold_build2_loc (loc, code, type, tem,
+				      build_zero_cst (itype));
+	    }
 	  if (operand_equal_p (arg00, arg11, 0))
-	    return fold_build2_loc (loc, code, type,
-				fold_build2_loc (loc, BIT_AND_EXPR, itype,
-					     fold_build2_loc (loc,
-							  BIT_XOR_EXPR, itype,
-							  arg01, arg10),
-					     arg00),
-				build_zero_cst (itype));
-
+	    {
+	      tem = fold_convert_loc (loc, itype, arg10);
+	      tem = fold_build2_loc (loc, BIT_XOR_EXPR, itype, arg01, tem);
+	      tem = fold_build2_loc (loc, BIT_AND_EXPR, itype, tem, arg00);
+	      return fold_build2_loc (loc, code, type, tem,
+				      build_zero_cst (itype));
+	    }
 	  if (operand_equal_p (arg00, arg10, 0))
-	    return fold_build2_loc (loc, code, type,
-				fold_build2_loc (loc, BIT_AND_EXPR, itype,
-					     fold_build2_loc (loc,
-							  BIT_XOR_EXPR, itype,
-							  arg01, arg11),
-					     arg00),
-				build_zero_cst (itype));
+	    {
+	      tem = fold_convert_loc (loc, itype, arg11);
+	      tem = fold_build2_loc (loc, BIT_XOR_EXPR, itype, arg01, tem);
+	      tem = fold_build2_loc (loc, BIT_AND_EXPR, itype, tem, arg00);
+	      return fold_build2_loc (loc, code, type, tem,
+				      build_zero_cst (itype));
+	    }
 	}
 
       if (TREE_CODE (arg0) == BIT_XOR_EXPR
diff --git gcc/testsuite/c-c++-common/ubsan/pr80349.c gcc/testsuite/c-c++-common/ubsan/pr80349.c
index e69de29..eb2e3da 100644
--- gcc/testsuite/c-c++-common/ubsan/pr80349.c
+++ gcc/testsuite/c-c++-common/ubsan/pr80349.c
@@ -0,0 +1,30 @@ 
+/* PR sanitizer/80349 */
+/* { dg-do compile } */
+/* { dg-options "-fsanitize=undefined" } */
+
+int var;
+long a;
+
+long
+fn1 ()
+{
+  return 0 % ((a & 1) == (7UL & 1));
+}
+
+long
+fn2 ()
+{
+  return 0 % ((a & 1) == (1 & 7UL));
+}
+
+long
+fn3 ()
+{
+  return 0 % ((1 & a) == (7UL & 1));
+}
+
+long
+fn4 ()
+{
+  return 0 % ((1 & a) == (1 & 7UL));
+}