This is the mail archive of the gcc-patches@gcc.gnu.org mailing list for the GCC project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: [PATCH] Properly honor -fsanitize options (PR sanitizer/58443)


On Wed, Sep 18, 2013 at 03:15:05PM +0200, Jakub Jelinek wrote:
> On Wed, Sep 18, 2013 at 03:10:42PM +0200, Marek Polacek wrote:
> > --- gcc/cp/typeck.c.mp	2013-09-18 14:00:14.303869196 +0200
> > +++ gcc/cp/typeck.c	2013-09-18 14:08:21.287770112 +0200
> > @@ -4884,7 +4884,7 @@ cp_build_binary_op (location_t location,
> >    if (build_type == NULL_TREE)
> >      build_type = result_type;
> >  
> > -  if ((flag_sanitize & SANITIZE_UNDEFINED)
> > +  if ((flag_sanitize & SANITIZE_SHIFT || flag_sanitize & SANITIZE_DIVIDE)
> 
> I'd suggest to use
>     if ((flag & (SANITIZE_SHIFT | SANITIZE_DIVIDE))
> instead.
> 
> >        && !processing_template_decl
> >        && current_function_decl != 0
> >        && !lookup_attribute ("no_sanitize_undefined",
> > @@ -4898,7 +4898,7 @@ cp_build_binary_op (location_t location,
> >  								  tf_none));
> >        op1 = maybe_constant_value (fold_non_dependent_expr_sfinae (op1,
> >  								  tf_none));
> > -      if (doing_div_or_mod)
> > +      if (doing_div_or_mod && flag_sanitize & SANITIZE_DIVIDE)
> 
> And, while the operator precedence is right, I think it would be better
> to use if (doing_div_or_mod && (flag_sanitize & SANITIZE_DIVIDE))

Thanks, fixed in both FEs.  Re-ran the ubsan testsuite.  Ok now?

2013-09-18  Marek Polacek  <polacek@redhat.com>

	PR sanitize/58443
cp/
	* typeck.c (cp_build_binary_op): Properly honor -fsanitize options.
	Remove unnecessary check.

c/
	* c-typeck.c (build_binary_op): Properly honor -fsanitize options.
	Remove unnecessary check.

testsuite/
	* g++.dg/ubsan/div-by-zero-1.C: Use the integer-divide-by-zero option
	instead of the shift option.
	* c-c++-common/ubsan/pr58443-1.c: New test.
	* c-c++-common/ubsan/pr58443-3.c: New test.
	* c-c++-common/ubsan/pr58443-2.c: New test.

--- gcc/cp/typeck.c.mp	2013-09-18 14:00:14.303869196 +0200
+++ gcc/cp/typeck.c	2013-09-18 15:19:56.601920206 +0200
@@ -4884,7 +4884,7 @@ cp_build_binary_op (location_t location,
   if (build_type == NULL_TREE)
     build_type = result_type;
 
-  if ((flag_sanitize & SANITIZE_UNDEFINED)
+  if ((flag_sanitize & (SANITIZE_SHIFT | SANITIZE_DIVIDE))
       && !processing_template_decl
       && current_function_decl != 0
       && !lookup_attribute ("no_sanitize_undefined",
@@ -4898,7 +4898,7 @@ cp_build_binary_op (location_t location,
 								  tf_none));
       op1 = maybe_constant_value (fold_non_dependent_expr_sfinae (op1,
 								  tf_none));
-      if (doing_div_or_mod)
+      if (doing_div_or_mod && (flag_sanitize & SANITIZE_DIVIDE))
 	{
 	  /* For diagnostics we want to use the promoted types without
 	     shorten_binary_op.  So convert the arguments to the
@@ -4912,7 +4912,7 @@ cp_build_binary_op (location_t location,
 	    }
 	  instrument_expr = ubsan_instrument_division (location, cop0, cop1);
 	}
-      else if (doing_shift)
+      else if (doing_shift && (flag_sanitize & SANITIZE_SHIFT))
 	instrument_expr = ubsan_instrument_shift (location, code, op0, op1);
     }
 
@@ -4926,7 +4926,7 @@ cp_build_binary_op (location_t location,
       && !TREE_OVERFLOW_P (op1))
     overflow_warning (location, result);
 
-  if ((flag_sanitize & SANITIZE_UNDEFINED) && instrument_expr != NULL)
+  if (instrument_expr != NULL)
     result = fold_build2 (COMPOUND_EXPR, TREE_TYPE (result),
 			  instrument_expr, result);
 
--- gcc/c/c-typeck.c.mp	2013-09-18 14:00:06.704837584 +0200
+++ gcc/c/c-typeck.c	2013-09-18 15:20:10.263972487 +0200
@@ -10496,7 +10496,7 @@ build_binary_op (location_t location, en
 	return error_mark_node;
     }
 
-  if (flag_sanitize & SANITIZE_UNDEFINED
+  if ((flag_sanitize & (SANITIZE_SHIFT | SANITIZE_DIVIDE))
       && current_function_decl != 0
       && !lookup_attribute ("no_sanitize_undefined",
 			    DECL_ATTRIBUTES (current_function_decl))
@@ -10507,9 +10507,9 @@ build_binary_op (location_t location, en
       op1 = c_save_expr (op1);
       op0 = c_fully_fold (op0, false, NULL);
       op1 = c_fully_fold (op1, false, NULL);
-      if (doing_div_or_mod)
+      if (doing_div_or_mod && (flag_sanitize & SANITIZE_DIVIDE))
 	instrument_expr = ubsan_instrument_division (location, op0, op1);
-      else if (doing_shift)
+      else if (doing_shift && (flag_sanitize & SANITIZE_SHIFT))
 	instrument_expr = ubsan_instrument_shift (location, code, op0, op1);
     }
 
@@ -10537,7 +10537,7 @@ build_binary_op (location_t location, en
     ret = build1 (EXCESS_PRECISION_EXPR, semantic_result_type, ret);
   protected_set_expr_location (ret, location);
 
-  if ((flag_sanitize & SANITIZE_UNDEFINED) && instrument_expr != NULL)
+  if (instrument_expr != NULL)
     ret = fold_build2 (COMPOUND_EXPR, TREE_TYPE (ret),
 		       instrument_expr, ret);
 
--- gcc/testsuite/g++.dg/ubsan/div-by-zero-1.C.mp	2013-09-18 14:24:42.735312422 +0200
+++ gcc/testsuite/g++.dg/ubsan/div-by-zero-1.C	2013-09-18 14:25:28.965491706 +0200
@@ -1,5 +1,5 @@
 /* { dg-do compile } */
-/* { dg-options "-fsanitize=shift -w" } */
+/* { dg-options "-fsanitize=integer-divide-by-zero -w" } */
 
 void
 foo (int i)
--- gcc/testsuite/c-c++-common/ubsan/pr58443-1.c.mp	2013-09-18 14:20:18.633348043 +0200
+++ gcc/testsuite/c-c++-common/ubsan/pr58443-1.c	2013-09-18 14:30:45.403701302 +0200
@@ -0,0 +1,11 @@
+/* PR sanitizer/58443 */
+/* { dg-do compile } */
+/* { dg-options "-fsanitize=shift,unreachable -w" } */
+
+int
+foo (int u, int o)
+{
+  return u / o;
+}
+
+/* { dg-final { scan-assembler-not "__ubsan_handle_divrem_overflow" } } */
--- gcc/testsuite/c-c++-common/ubsan/pr58443-3.c.mp	2013-09-18 14:20:31.724398731 +0200
+++ gcc/testsuite/c-c++-common/ubsan/pr58443-3.c	2013-09-18 14:30:23.959623394 +0200
@@ -0,0 +1,18 @@
+/* PR sanitizer/58443 */
+/* { dg-do compile } */
+/* { dg-options "-fsanitize=undefined -w" } */
+
+int
+foo (int u, int o)
+{
+  return u >> o;
+}
+
+int
+bar (int u, int o)
+{
+  return u / o;
+}
+
+/* { dg-final { scan-assembler "__ubsan_handle_divrem_overflow" } } */
+/* { dg-final { scan-assembler "__ubsan_handle_shift_out_of_bounds" } } */
--- gcc/testsuite/c-c++-common/ubsan/pr58443-2.c.mp	2013-09-18 14:20:27.692384073 +0200
+++ gcc/testsuite/c-c++-common/ubsan/pr58443-2.c	2013-09-18 14:28:17.272155763 +0200
@@ -0,0 +1,11 @@
+/* PR sanitizer/58443 */
+/* { dg-do compile } */
+/* { dg-options "-fsanitize=unreachable,integer-divide-by-zero -w" } */
+
+int
+foo (int u, int o)
+{
+  return u >> o;
+}
+
+/* { dg-final { scan-assembler-not "__ubsan_handle_shift_out_of_bounds" } } */

	Marek


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]