* [PATCH] Add no_sanitize_coverage attribute.
@ 2021-05-20 8:33 Martin Liška
2021-05-20 8:45 ` Marco Elver
0 siblings, 1 reply; 9+ messages in thread
From: Martin Liška @ 2021-05-20 8:33 UTC (permalink / raw)
To: gcc-patches; +Cc: Marco Elver, Nick Desaulniers
Hello.
The patch implements one missing attribute which can be used for per-function
disabling of coverage sanitization.
Patch can bootstrap on x86_64-linux-gnu and survives regression tests.
Ready to be installed?
Thanks,
Martin
gcc/ChangeLog:
* asan.h (sanitize_coverage_p): New function.
* doc/extend.texi: Document it.
* fold-const.c (fold_range_test): Use sanitize_flags_p
instead of flag_sanitize_coverage.
(fold_truth_andor): Likewise.
* sancov.c: Likewise.
* tree-ssa-ifcombine.c (ifcombine_ifandif): Likewise.
gcc/c-family/ChangeLog:
* c-attribs.c (handle_no_sanitize_coverage_attribute): New.
gcc/testsuite/ChangeLog:
* gcc.dg/sancov/attribute.c: New test.
---
gcc/asan.h | 10 ++++++++++
gcc/c-family/c-attribs.c | 20 ++++++++++++++++++++
gcc/doc/extend.texi | 6 ++++++
gcc/fold-const.c | 4 ++--
gcc/sancov.c | 4 ++--
gcc/testsuite/gcc.dg/sancov/attribute.c | 15 +++++++++++++++
gcc/tree-ssa-ifcombine.c | 4 +++-
7 files changed, 58 insertions(+), 5 deletions(-)
create mode 100644 gcc/testsuite/gcc.dg/sancov/attribute.c
diff --git a/gcc/asan.h b/gcc/asan.h
index f110f1db563..8c0b2baf170 100644
--- a/gcc/asan.h
+++ b/gcc/asan.h
@@ -249,4 +249,14 @@ sanitize_flags_p (unsigned int flag, const_tree fn = current_function_decl)
return result_flags;
}
+/* Return true when coverage sanitization should happend for FN function. */
+
+static inline bool
+sanitize_coverage_p (const_tree fn = current_function_decl)
+{
+ return (flag_sanitize_coverage
+ && lookup_attribute ("no_sanitize_coverage",
+ DECL_ATTRIBUTES (fn)) == NULL_TREE);
+}
+
#endif /* TREE_ASAN */
diff --git a/gcc/c-family/c-attribs.c b/gcc/c-family/c-attribs.c
index ccf9e4ccf0b..671b27c3200 100644
--- a/gcc/c-family/c-attribs.c
+++ b/gcc/c-family/c-attribs.c
@@ -62,6 +62,8 @@ static tree handle_no_address_safety_analysis_attribute (tree *, tree, tree,
int, bool *);
static tree handle_no_sanitize_undefined_attribute (tree *, tree, tree, int,
bool *);
+static tree handle_no_sanitize_coverage_attribute (tree *, tree, tree, int,
+ bool *);
static tree handle_asan_odr_indicator_attribute (tree *, tree, tree, int,
bool *);
static tree handle_stack_protect_attribute (tree *, tree, tree, int, bool *);
@@ -449,6 +451,8 @@ const struct attribute_spec c_common_attribute_table[] =
handle_no_sanitize_thread_attribute, NULL },
{ "no_sanitize_undefined", 0, 0, true, false, false, false,
handle_no_sanitize_undefined_attribute, NULL },
+ { "no_sanitize_coverage", 0, 0, true, false, false, false,
+ handle_no_sanitize_coverage_attribute, NULL },
{ "asan odr indicator", 0, 0, true, false, false, false,
handle_asan_odr_indicator_attribute, NULL },
{ "warning", 1, 1, true, false, false, false,
@@ -1211,6 +1215,22 @@ handle_no_sanitize_undefined_attribute (tree *node, tree name, tree, int,
return NULL_TREE;
}
+/* Handle a "no_sanitize_coverage" attribute; arguments as in
+ struct attribute_spec.handler. */
+
+static tree
+handle_no_sanitize_coverage_attribute (tree *node, tree name, tree, int,
+ bool *no_add_attrs)
+{
+ if (TREE_CODE (*node) != FUNCTION_DECL)
+ {
+ warning (OPT_Wattributes, "%qE attribute ignored", name);
+ *no_add_attrs = true;
+ }
+
+ return NULL_TREE;
+}
+
/* Handle an "asan odr indicator" attribute; arguments as in
struct attribute_spec.handler. */
diff --git a/gcc/doc/extend.texi b/gcc/doc/extend.texi
index 826804e6149..3ddeb0dee3a 100644
--- a/gcc/doc/extend.texi
+++ b/gcc/doc/extend.texi
@@ -3415,6 +3415,12 @@ The @code{no_sanitize_undefined} attribute on functions is used
to inform the compiler that it should not check for undefined behavior
in the function when compiling with the @option{-fsanitize=undefined} option.
+@item no_sanitize_coverage
+@cindex @code{no_sanitize_coverage} function attribute
+The @code{no_sanitize_coverage} attribute on functions is used
+to inform the compiler that it should not do coverage-guided
+fuzzing code instrumentation (@option{-fsanitize-coverage}).
+
@item no_split_stack
@cindex @code{no_split_stack} function attribute
@opindex fsplit-stack
diff --git a/gcc/fold-const.c b/gcc/fold-const.c
index 3be9c15e6b2..d088187a057 100644
--- a/gcc/fold-const.c
+++ b/gcc/fold-const.c
@@ -6016,7 +6016,7 @@ fold_range_test (location_t loc, enum tree_code code, tree type,
logical_op_non_short_circuit
= param_logical_op_non_short_circuit;
if (logical_op_non_short_circuit
- && !flag_sanitize_coverage
+ && !sanitize_coverage_p ()
&& lhs != 0 && rhs != 0
&& (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR)
&& operand_equal_p (lhs, rhs, 0))
@@ -9652,7 +9652,7 @@ fold_truth_andor (location_t loc, enum tree_code code, tree type,
logical_op_non_short_circuit
= param_logical_op_non_short_circuit;
if (logical_op_non_short_circuit
- && !flag_sanitize_coverage
+ && !sanitize_coverage_p ()
&& (code == TRUTH_AND_EXPR
|| code == TRUTH_ANDIF_EXPR
|| code == TRUTH_OR_EXPR
diff --git a/gcc/sancov.c b/gcc/sancov.c
index d656c37cae9..9cfbd425def 100644
--- a/gcc/sancov.c
+++ b/gcc/sancov.c
@@ -313,9 +313,9 @@ public:
return new pass_sancov<O0> (m_ctxt);
}
virtual bool
- gate (function *)
+ gate (function *fun)
{
- return flag_sanitize_coverage && (!O0 || !optimize);
+ return sanitize_coverage_p (fun->decl) && (!O0 || !optimize);
}
virtual unsigned int
execute (function *fun)
diff --git a/gcc/testsuite/gcc.dg/sancov/attribute.c b/gcc/testsuite/gcc.dg/sancov/attribute.c
new file mode 100644
index 00000000000..bf6dbd4bae7
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/sancov/attribute.c
@@ -0,0 +1,15 @@
+/* { dg-do compile } */
+/* { dg-options "-fsanitize-coverage=trace-pc -fdump-tree-optimized" } */
+
+void foo(void)
+{
+}
+
+void
+__attribute__((no_sanitize_coverage))
+bar(void)
+{
+}
+
+
+/* { dg-final { scan-tree-dump-times "__builtin___sanitizer_cov_trace_pc \\(\\)" 1 "optimized" } } */
diff --git a/gcc/tree-ssa-ifcombine.c b/gcc/tree-ssa-ifcombine.c
index 836a12d6b80..f93e04aa4df 100644
--- a/gcc/tree-ssa-ifcombine.c
+++ b/gcc/tree-ssa-ifcombine.c
@@ -40,6 +40,8 @@ along with GCC; see the file COPYING3. If not see
#include "gimplify-me.h"
#include "tree-cfg.h"
#include "tree-ssa.h"
+#include "attribs.h"
+#include "asan.h"
#ifndef LOGICAL_OP_NON_SHORT_CIRCUIT
#define LOGICAL_OP_NON_SHORT_CIRCUIT \
@@ -567,7 +569,7 @@ ifcombine_ifandif (basic_block inner_cond_bb, bool inner_inv,
if (param_logical_op_non_short_circuit != -1)
logical_op_non_short_circuit
= param_logical_op_non_short_circuit;
- if (!logical_op_non_short_circuit || flag_sanitize_coverage)
+ if (!logical_op_non_short_circuit || sanitize_coverage_p ())
return false;
/* Only do this optimization if the inner bb contains only the conditional. */
if (!gsi_one_before_end_p (gsi_start_nondebug_after_labels_bb (inner_cond_bb)))
--
2.31.1
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] Add no_sanitize_coverage attribute.
2021-05-20 8:33 [PATCH] Add no_sanitize_coverage attribute Martin Liška
@ 2021-05-20 8:45 ` Marco Elver
2021-05-20 9:08 ` Martin Liška
0 siblings, 1 reply; 9+ messages in thread
From: Marco Elver @ 2021-05-20 8:45 UTC (permalink / raw)
To: Martin Liška; +Cc: GCC Patches, Nick Desaulniers
On Thu, 20 May 2021 at 10:33, Martin Liška <mliska@suse.cz> wrote:
> Hello.
>
> The patch implements one missing attribute which can be used for per-function
> disabling of coverage sanitization.
>
> Patch can bootstrap on x86_64-linux-gnu and survives regression tests.
Thanks for implementing this so quickly. One thing I just have to
double check, is if this works with always_inline (not instrumented if
inlined into no_sanitize), and inline (not inlined if inline fn is
no_sanitize_coverage). Just like the other no_sanitize* do. The test
doesn't mention them.
Thanks,
-- Marco
> Ready to be installed?
> Thanks,
> Martin
>
> gcc/ChangeLog:
>
> * asan.h (sanitize_coverage_p): New function.
> * doc/extend.texi: Document it.
> * fold-const.c (fold_range_test): Use sanitize_flags_p
> instead of flag_sanitize_coverage.
> (fold_truth_andor): Likewise.
> * sancov.c: Likewise.
> * tree-ssa-ifcombine.c (ifcombine_ifandif): Likewise.
>
> gcc/c-family/ChangeLog:
>
> * c-attribs.c (handle_no_sanitize_coverage_attribute): New.
>
> gcc/testsuite/ChangeLog:
>
> * gcc.dg/sancov/attribute.c: New test.
> ---
> gcc/asan.h | 10 ++++++++++
> gcc/c-family/c-attribs.c | 20 ++++++++++++++++++++
> gcc/doc/extend.texi | 6 ++++++
> gcc/fold-const.c | 4 ++--
> gcc/sancov.c | 4 ++--
> gcc/testsuite/gcc.dg/sancov/attribute.c | 15 +++++++++++++++
> gcc/tree-ssa-ifcombine.c | 4 +++-
> 7 files changed, 58 insertions(+), 5 deletions(-)
> create mode 100644 gcc/testsuite/gcc.dg/sancov/attribute.c
>
> diff --git a/gcc/asan.h b/gcc/asan.h
> index f110f1db563..8c0b2baf170 100644
> --- a/gcc/asan.h
> +++ b/gcc/asan.h
> @@ -249,4 +249,14 @@ sanitize_flags_p (unsigned int flag, const_tree fn = current_function_decl)
> return result_flags;
> }
>
> +/* Return true when coverage sanitization should happend for FN function. */
> +
> +static inline bool
> +sanitize_coverage_p (const_tree fn = current_function_decl)
> +{
> + return (flag_sanitize_coverage
> + && lookup_attribute ("no_sanitize_coverage",
> + DECL_ATTRIBUTES (fn)) == NULL_TREE);
> +}
> +
> #endif /* TREE_ASAN */
> diff --git a/gcc/c-family/c-attribs.c b/gcc/c-family/c-attribs.c
> index ccf9e4ccf0b..671b27c3200 100644
> --- a/gcc/c-family/c-attribs.c
> +++ b/gcc/c-family/c-attribs.c
> @@ -62,6 +62,8 @@ static tree handle_no_address_safety_analysis_attribute (tree *, tree, tree,
> int, bool *);
> static tree handle_no_sanitize_undefined_attribute (tree *, tree, tree, int,
> bool *);
> +static tree handle_no_sanitize_coverage_attribute (tree *, tree, tree, int,
> + bool *);
> static tree handle_asan_odr_indicator_attribute (tree *, tree, tree, int,
> bool *);
> static tree handle_stack_protect_attribute (tree *, tree, tree, int, bool *);
> @@ -449,6 +451,8 @@ const struct attribute_spec c_common_attribute_table[] =
> handle_no_sanitize_thread_attribute, NULL },
> { "no_sanitize_undefined", 0, 0, true, false, false, false,
> handle_no_sanitize_undefined_attribute, NULL },
> + { "no_sanitize_coverage", 0, 0, true, false, false, false,
> + handle_no_sanitize_coverage_attribute, NULL },
> { "asan odr indicator", 0, 0, true, false, false, false,
> handle_asan_odr_indicator_attribute, NULL },
> { "warning", 1, 1, true, false, false, false,
> @@ -1211,6 +1215,22 @@ handle_no_sanitize_undefined_attribute (tree *node, tree name, tree, int,
> return NULL_TREE;
> }
>
> +/* Handle a "no_sanitize_coverage" attribute; arguments as in
> + struct attribute_spec.handler. */
> +
> +static tree
> +handle_no_sanitize_coverage_attribute (tree *node, tree name, tree, int,
> + bool *no_add_attrs)
> +{
> + if (TREE_CODE (*node) != FUNCTION_DECL)
> + {
> + warning (OPT_Wattributes, "%qE attribute ignored", name);
> + *no_add_attrs = true;
> + }
> +
> + return NULL_TREE;
> +}
> +
> /* Handle an "asan odr indicator" attribute; arguments as in
> struct attribute_spec.handler. */
>
> diff --git a/gcc/doc/extend.texi b/gcc/doc/extend.texi
> index 826804e6149..3ddeb0dee3a 100644
> --- a/gcc/doc/extend.texi
> +++ b/gcc/doc/extend.texi
> @@ -3415,6 +3415,12 @@ The @code{no_sanitize_undefined} attribute on functions is used
> to inform the compiler that it should not check for undefined behavior
> in the function when compiling with the @option{-fsanitize=undefined} option.
>
> +@item no_sanitize_coverage
> +@cindex @code{no_sanitize_coverage} function attribute
> +The @code{no_sanitize_coverage} attribute on functions is used
> +to inform the compiler that it should not do coverage-guided
> +fuzzing code instrumentation (@option{-fsanitize-coverage}).
> +
> @item no_split_stack
> @cindex @code{no_split_stack} function attribute
> @opindex fsplit-stack
> diff --git a/gcc/fold-const.c b/gcc/fold-const.c
> index 3be9c15e6b2..d088187a057 100644
> --- a/gcc/fold-const.c
> +++ b/gcc/fold-const.c
> @@ -6016,7 +6016,7 @@ fold_range_test (location_t loc, enum tree_code code, tree type,
> logical_op_non_short_circuit
> = param_logical_op_non_short_circuit;
> if (logical_op_non_short_circuit
> - && !flag_sanitize_coverage
> + && !sanitize_coverage_p ()
> && lhs != 0 && rhs != 0
> && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR)
> && operand_equal_p (lhs, rhs, 0))
> @@ -9652,7 +9652,7 @@ fold_truth_andor (location_t loc, enum tree_code code, tree type,
> logical_op_non_short_circuit
> = param_logical_op_non_short_circuit;
> if (logical_op_non_short_circuit
> - && !flag_sanitize_coverage
> + && !sanitize_coverage_p ()
> && (code == TRUTH_AND_EXPR
> || code == TRUTH_ANDIF_EXPR
> || code == TRUTH_OR_EXPR
> diff --git a/gcc/sancov.c b/gcc/sancov.c
> index d656c37cae9..9cfbd425def 100644
> --- a/gcc/sancov.c
> +++ b/gcc/sancov.c
> @@ -313,9 +313,9 @@ public:
> return new pass_sancov<O0> (m_ctxt);
> }
> virtual bool
> - gate (function *)
> + gate (function *fun)
> {
> - return flag_sanitize_coverage && (!O0 || !optimize);
> + return sanitize_coverage_p (fun->decl) && (!O0 || !optimize);
> }
> virtual unsigned int
> execute (function *fun)
> diff --git a/gcc/testsuite/gcc.dg/sancov/attribute.c b/gcc/testsuite/gcc.dg/sancov/attribute.c
> new file mode 100644
> index 00000000000..bf6dbd4bae7
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/sancov/attribute.c
> @@ -0,0 +1,15 @@
> +/* { dg-do compile } */
> +/* { dg-options "-fsanitize-coverage=trace-pc -fdump-tree-optimized" } */
> +
> +void foo(void)
> +{
> +}
> +
> +void
> +__attribute__((no_sanitize_coverage))
> +bar(void)
> +{
> +}
> +
> +
> +/* { dg-final { scan-tree-dump-times "__builtin___sanitizer_cov_trace_pc \\(\\)" 1 "optimized" } } */
> diff --git a/gcc/tree-ssa-ifcombine.c b/gcc/tree-ssa-ifcombine.c
> index 836a12d6b80..f93e04aa4df 100644
> --- a/gcc/tree-ssa-ifcombine.c
> +++ b/gcc/tree-ssa-ifcombine.c
> @@ -40,6 +40,8 @@ along with GCC; see the file COPYING3. If not see
> #include "gimplify-me.h"
> #include "tree-cfg.h"
> #include "tree-ssa.h"
> +#include "attribs.h"
> +#include "asan.h"
>
> #ifndef LOGICAL_OP_NON_SHORT_CIRCUIT
> #define LOGICAL_OP_NON_SHORT_CIRCUIT \
> @@ -567,7 +569,7 @@ ifcombine_ifandif (basic_block inner_cond_bb, bool inner_inv,
> if (param_logical_op_non_short_circuit != -1)
> logical_op_non_short_circuit
> = param_logical_op_non_short_circuit;
> - if (!logical_op_non_short_circuit || flag_sanitize_coverage)
> + if (!logical_op_non_short_circuit || sanitize_coverage_p ())
> return false;
> /* Only do this optimization if the inner bb contains only the conditional. */
> if (!gsi_one_before_end_p (gsi_start_nondebug_after_labels_bb (inner_cond_bb)))
> --
> 2.31.1
>
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] Add no_sanitize_coverage attribute.
2021-05-20 8:45 ` Marco Elver
@ 2021-05-20 9:08 ` Martin Liška
2021-05-20 10:55 ` Marco Elver
0 siblings, 1 reply; 9+ messages in thread
From: Martin Liška @ 2021-05-20 9:08 UTC (permalink / raw)
To: Marco Elver; +Cc: GCC Patches, Nick Desaulniers
On 5/20/21 10:45 AM, Marco Elver wrote:
> On Thu, 20 May 2021 at 10:33, Martin Liška <mliska@suse.cz> wrote:
>> Hello.
>>
>> The patch implements one missing attribute which can be used for per-function
>> disabling of coverage sanitization.
>>
>> Patch can bootstrap on x86_64-linux-gnu and survives regression tests.
>
> Thanks for implementing this so quickly. One thing I just have to
> double check, is if this works with always_inline (not instrumented if
> inlined into no_sanitize),
No, in this case it's instrumented (if caller has not set the attribute).
> and inline (not inlined if inline fn is
> no_sanitize_coverage).
No again, it's not blocking inlining.
> Just like the other no_sanitize* do. The test doesn't mention them.
It's aligned with similar issue that was discussed some time ago:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94722#c9
Martin
>
> Thanks,
> -- Marco
>
>> Ready to be installed?
>> Thanks,
>> Martin
>>
>> gcc/ChangeLog:
>>
>> * asan.h (sanitize_coverage_p): New function.
>> * doc/extend.texi: Document it.
>> * fold-const.c (fold_range_test): Use sanitize_flags_p
>> instead of flag_sanitize_coverage.
>> (fold_truth_andor): Likewise.
>> * sancov.c: Likewise.
>> * tree-ssa-ifcombine.c (ifcombine_ifandif): Likewise.
>>
>> gcc/c-family/ChangeLog:
>>
>> * c-attribs.c (handle_no_sanitize_coverage_attribute): New.
>>
>> gcc/testsuite/ChangeLog:
>>
>> * gcc.dg/sancov/attribute.c: New test.
>> ---
>> gcc/asan.h | 10 ++++++++++
>> gcc/c-family/c-attribs.c | 20 ++++++++++++++++++++
>> gcc/doc/extend.texi | 6 ++++++
>> gcc/fold-const.c | 4 ++--
>> gcc/sancov.c | 4 ++--
>> gcc/testsuite/gcc.dg/sancov/attribute.c | 15 +++++++++++++++
>> gcc/tree-ssa-ifcombine.c | 4 +++-
>> 7 files changed, 58 insertions(+), 5 deletions(-)
>> create mode 100644 gcc/testsuite/gcc.dg/sancov/attribute.c
>>
>> diff --git a/gcc/asan.h b/gcc/asan.h
>> index f110f1db563..8c0b2baf170 100644
>> --- a/gcc/asan.h
>> +++ b/gcc/asan.h
>> @@ -249,4 +249,14 @@ sanitize_flags_p (unsigned int flag, const_tree fn = current_function_decl)
>> return result_flags;
>> }
>>
>> +/* Return true when coverage sanitization should happend for FN function. */
>> +
>> +static inline bool
>> +sanitize_coverage_p (const_tree fn = current_function_decl)
>> +{
>> + return (flag_sanitize_coverage
>> + && lookup_attribute ("no_sanitize_coverage",
>> + DECL_ATTRIBUTES (fn)) == NULL_TREE);
>> +}
>> +
>> #endif /* TREE_ASAN */
>> diff --git a/gcc/c-family/c-attribs.c b/gcc/c-family/c-attribs.c
>> index ccf9e4ccf0b..671b27c3200 100644
>> --- a/gcc/c-family/c-attribs.c
>> +++ b/gcc/c-family/c-attribs.c
>> @@ -62,6 +62,8 @@ static tree handle_no_address_safety_analysis_attribute (tree *, tree, tree,
>> int, bool *);
>> static tree handle_no_sanitize_undefined_attribute (tree *, tree, tree, int,
>> bool *);
>> +static tree handle_no_sanitize_coverage_attribute (tree *, tree, tree, int,
>> + bool *);
>> static tree handle_asan_odr_indicator_attribute (tree *, tree, tree, int,
>> bool *);
>> static tree handle_stack_protect_attribute (tree *, tree, tree, int, bool *);
>> @@ -449,6 +451,8 @@ const struct attribute_spec c_common_attribute_table[] =
>> handle_no_sanitize_thread_attribute, NULL },
>> { "no_sanitize_undefined", 0, 0, true, false, false, false,
>> handle_no_sanitize_undefined_attribute, NULL },
>> + { "no_sanitize_coverage", 0, 0, true, false, false, false,
>> + handle_no_sanitize_coverage_attribute, NULL },
>> { "asan odr indicator", 0, 0, true, false, false, false,
>> handle_asan_odr_indicator_attribute, NULL },
>> { "warning", 1, 1, true, false, false, false,
>> @@ -1211,6 +1215,22 @@ handle_no_sanitize_undefined_attribute (tree *node, tree name, tree, int,
>> return NULL_TREE;
>> }
>>
>> +/* Handle a "no_sanitize_coverage" attribute; arguments as in
>> + struct attribute_spec.handler. */
>> +
>> +static tree
>> +handle_no_sanitize_coverage_attribute (tree *node, tree name, tree, int,
>> + bool *no_add_attrs)
>> +{
>> + if (TREE_CODE (*node) != FUNCTION_DECL)
>> + {
>> + warning (OPT_Wattributes, "%qE attribute ignored", name);
>> + *no_add_attrs = true;
>> + }
>> +
>> + return NULL_TREE;
>> +}
>> +
>> /* Handle an "asan odr indicator" attribute; arguments as in
>> struct attribute_spec.handler. */
>>
>> diff --git a/gcc/doc/extend.texi b/gcc/doc/extend.texi
>> index 826804e6149..3ddeb0dee3a 100644
>> --- a/gcc/doc/extend.texi
>> +++ b/gcc/doc/extend.texi
>> @@ -3415,6 +3415,12 @@ The @code{no_sanitize_undefined} attribute on functions is used
>> to inform the compiler that it should not check for undefined behavior
>> in the function when compiling with the @option{-fsanitize=undefined} option.
>>
>> +@item no_sanitize_coverage
>> +@cindex @code{no_sanitize_coverage} function attribute
>> +The @code{no_sanitize_coverage} attribute on functions is used
>> +to inform the compiler that it should not do coverage-guided
>> +fuzzing code instrumentation (@option{-fsanitize-coverage}).
>> +
>> @item no_split_stack
>> @cindex @code{no_split_stack} function attribute
>> @opindex fsplit-stack
>> diff --git a/gcc/fold-const.c b/gcc/fold-const.c
>> index 3be9c15e6b2..d088187a057 100644
>> --- a/gcc/fold-const.c
>> +++ b/gcc/fold-const.c
>> @@ -6016,7 +6016,7 @@ fold_range_test (location_t loc, enum tree_code code, tree type,
>> logical_op_non_short_circuit
>> = param_logical_op_non_short_circuit;
>> if (logical_op_non_short_circuit
>> - && !flag_sanitize_coverage
>> + && !sanitize_coverage_p ()
>> && lhs != 0 && rhs != 0
>> && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR)
>> && operand_equal_p (lhs, rhs, 0))
>> @@ -9652,7 +9652,7 @@ fold_truth_andor (location_t loc, enum tree_code code, tree type,
>> logical_op_non_short_circuit
>> = param_logical_op_non_short_circuit;
>> if (logical_op_non_short_circuit
>> - && !flag_sanitize_coverage
>> + && !sanitize_coverage_p ()
>> && (code == TRUTH_AND_EXPR
>> || code == TRUTH_ANDIF_EXPR
>> || code == TRUTH_OR_EXPR
>> diff --git a/gcc/sancov.c b/gcc/sancov.c
>> index d656c37cae9..9cfbd425def 100644
>> --- a/gcc/sancov.c
>> +++ b/gcc/sancov.c
>> @@ -313,9 +313,9 @@ public:
>> return new pass_sancov<O0> (m_ctxt);
>> }
>> virtual bool
>> - gate (function *)
>> + gate (function *fun)
>> {
>> - return flag_sanitize_coverage && (!O0 || !optimize);
>> + return sanitize_coverage_p (fun->decl) && (!O0 || !optimize);
>> }
>> virtual unsigned int
>> execute (function *fun)
>> diff --git a/gcc/testsuite/gcc.dg/sancov/attribute.c b/gcc/testsuite/gcc.dg/sancov/attribute.c
>> new file mode 100644
>> index 00000000000..bf6dbd4bae7
>> --- /dev/null
>> +++ b/gcc/testsuite/gcc.dg/sancov/attribute.c
>> @@ -0,0 +1,15 @@
>> +/* { dg-do compile } */
>> +/* { dg-options "-fsanitize-coverage=trace-pc -fdump-tree-optimized" } */
>> +
>> +void foo(void)
>> +{
>> +}
>> +
>> +void
>> +__attribute__((no_sanitize_coverage))
>> +bar(void)
>> +{
>> +}
>> +
>> +
>> +/* { dg-final { scan-tree-dump-times "__builtin___sanitizer_cov_trace_pc \\(\\)" 1 "optimized" } } */
>> diff --git a/gcc/tree-ssa-ifcombine.c b/gcc/tree-ssa-ifcombine.c
>> index 836a12d6b80..f93e04aa4df 100644
>> --- a/gcc/tree-ssa-ifcombine.c
>> +++ b/gcc/tree-ssa-ifcombine.c
>> @@ -40,6 +40,8 @@ along with GCC; see the file COPYING3. If not see
>> #include "gimplify-me.h"
>> #include "tree-cfg.h"
>> #include "tree-ssa.h"
>> +#include "attribs.h"
>> +#include "asan.h"
>>
>> #ifndef LOGICAL_OP_NON_SHORT_CIRCUIT
>> #define LOGICAL_OP_NON_SHORT_CIRCUIT \
>> @@ -567,7 +569,7 @@ ifcombine_ifandif (basic_block inner_cond_bb, bool inner_inv,
>> if (param_logical_op_non_short_circuit != -1)
>> logical_op_non_short_circuit
>> = param_logical_op_non_short_circuit;
>> - if (!logical_op_non_short_circuit || flag_sanitize_coverage)
>> + if (!logical_op_non_short_circuit || sanitize_coverage_p ())
>> return false;
>> /* Only do this optimization if the inner bb contains only the conditional. */
>> if (!gsi_one_before_end_p (gsi_start_nondebug_after_labels_bb (inner_cond_bb)))
>> --
>> 2.31.1
>>
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] Add no_sanitize_coverage attribute.
2021-05-20 9:08 ` Martin Liška
@ 2021-05-20 10:55 ` Marco Elver
2021-05-21 8:50 ` Martin Liška
0 siblings, 1 reply; 9+ messages in thread
From: Marco Elver @ 2021-05-20 10:55 UTC (permalink / raw)
To: Martin Liška; +Cc: GCC Patches, Nick Desaulniers
On Thu, 20 May 2021 at 11:08, Martin Liška <mliska@suse.cz> wrote:
> On 5/20/21 10:45 AM, Marco Elver wrote:
> > On Thu, 20 May 2021 at 10:33, Martin Liška <mliska@suse.cz> wrote:
> >> Hello.
> >>
> >> The patch implements one missing attribute which can be used for per-function
> >> disabling of coverage sanitization.
> >>
> >> Patch can bootstrap on x86_64-linux-gnu and survives regression tests.
> >
> > Thanks for implementing this so quickly. One thing I just have to
> > double check, is if this works with always_inline (not instrumented if
> > inlined into no_sanitize),
>
> No, in this case it's instrumented (if caller has not set the attribute).
This one I'm not sure of, because in too many places, we assume
always_inline behaves like a macro (see below).
> > and inline (not inlined if inline fn is
> > no_sanitize_coverage).
>
> No again, it's not blocking inlining.
I think that's fine, as long as the inlined code is still instrumented
according to the attribute (which I think is the case based on what
you say above).
I think this came up with other no_sanitize [1] based on what I had
written to you last year [2].
[1] https://gcc.gnu.org/pipermail/gcc-patches/2020-June/547618.html
[2] https://lore.kernel.org/lkml/CANpmjNNRz5OVKb6PE7K6GjfoGbht_ZhyPkNG9aD+KjNDzK7hGg@mail.gmail.com/
> > Just like the other no_sanitize* do. The test doesn't mention them.
>
> It's aligned with similar issue that was discussed some time ago:
> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94722#c9
That's fair, but keep in mind all -fsanitize are not for use in
production, unlike stack protector. no_sanitize_coverage needs to be
aligned with the behavior of other existing no_sanitize*. Of course,
whether to inline or not I don't mind, as long as no_sanitize means
the code is never instrumented as discussed in [2]. AFAIK, it just so
happens that to achieve that for the other sanitizers, the easiest
option was to not inline "inline no_sanitize*" functions.
But always_inline needs to behave in line with other no_sanitize*,
i.e. if inlined into no_sanitize_coverage, never instrument:
https://lore.kernel.org/lkml/CANpmjNMTsY_8241bS7=XAfqvZHFLrVEkv_uM4aDUWE_kh3Rvbw@mail.gmail.com/
This is also what Clang will do for no_sanitize_coverage.
Thanks,
-- Marco
> Martin
>
> >
> > Thanks,
> > -- Marco
> >
> >> Ready to be installed?
> >> Thanks,
> >> Martin
> >>
> >> gcc/ChangeLog:
> >>
> >> * asan.h (sanitize_coverage_p): New function.
> >> * doc/extend.texi: Document it.
> >> * fold-const.c (fold_range_test): Use sanitize_flags_p
> >> instead of flag_sanitize_coverage.
> >> (fold_truth_andor): Likewise.
> >> * sancov.c: Likewise.
> >> * tree-ssa-ifcombine.c (ifcombine_ifandif): Likewise.
> >>
> >> gcc/c-family/ChangeLog:
> >>
> >> * c-attribs.c (handle_no_sanitize_coverage_attribute): New.
> >>
> >> gcc/testsuite/ChangeLog:
> >>
> >> * gcc.dg/sancov/attribute.c: New test.
> >> ---
> >> gcc/asan.h | 10 ++++++++++
> >> gcc/c-family/c-attribs.c | 20 ++++++++++++++++++++
> >> gcc/doc/extend.texi | 6 ++++++
> >> gcc/fold-const.c | 4 ++--
> >> gcc/sancov.c | 4 ++--
> >> gcc/testsuite/gcc.dg/sancov/attribute.c | 15 +++++++++++++++
> >> gcc/tree-ssa-ifcombine.c | 4 +++-
> >> 7 files changed, 58 insertions(+), 5 deletions(-)
> >> create mode 100644 gcc/testsuite/gcc.dg/sancov/attribute.c
> >>
> >> diff --git a/gcc/asan.h b/gcc/asan.h
> >> index f110f1db563..8c0b2baf170 100644
> >> --- a/gcc/asan.h
> >> +++ b/gcc/asan.h
> >> @@ -249,4 +249,14 @@ sanitize_flags_p (unsigned int flag, const_tree fn = current_function_decl)
> >> return result_flags;
> >> }
> >>
> >> +/* Return true when coverage sanitization should happend for FN function. */
> >> +
> >> +static inline bool
> >> +sanitize_coverage_p (const_tree fn = current_function_decl)
> >> +{
> >> + return (flag_sanitize_coverage
> >> + && lookup_attribute ("no_sanitize_coverage",
> >> + DECL_ATTRIBUTES (fn)) == NULL_TREE);
> >> +}
> >> +
> >> #endif /* TREE_ASAN */
> >> diff --git a/gcc/c-family/c-attribs.c b/gcc/c-family/c-attribs.c
> >> index ccf9e4ccf0b..671b27c3200 100644
> >> --- a/gcc/c-family/c-attribs.c
> >> +++ b/gcc/c-family/c-attribs.c
> >> @@ -62,6 +62,8 @@ static tree handle_no_address_safety_analysis_attribute (tree *, tree, tree,
> >> int, bool *);
> >> static tree handle_no_sanitize_undefined_attribute (tree *, tree, tree, int,
> >> bool *);
> >> +static tree handle_no_sanitize_coverage_attribute (tree *, tree, tree, int,
> >> + bool *);
> >> static tree handle_asan_odr_indicator_attribute (tree *, tree, tree, int,
> >> bool *);
> >> static tree handle_stack_protect_attribute (tree *, tree, tree, int, bool *);
> >> @@ -449,6 +451,8 @@ const struct attribute_spec c_common_attribute_table[] =
> >> handle_no_sanitize_thread_attribute, NULL },
> >> { "no_sanitize_undefined", 0, 0, true, false, false, false,
> >> handle_no_sanitize_undefined_attribute, NULL },
> >> + { "no_sanitize_coverage", 0, 0, true, false, false, false,
> >> + handle_no_sanitize_coverage_attribute, NULL },
> >> { "asan odr indicator", 0, 0, true, false, false, false,
> >> handle_asan_odr_indicator_attribute, NULL },
> >> { "warning", 1, 1, true, false, false, false,
> >> @@ -1211,6 +1215,22 @@ handle_no_sanitize_undefined_attribute (tree *node, tree name, tree, int,
> >> return NULL_TREE;
> >> }
> >>
> >> +/* Handle a "no_sanitize_coverage" attribute; arguments as in
> >> + struct attribute_spec.handler. */
> >> +
> >> +static tree
> >> +handle_no_sanitize_coverage_attribute (tree *node, tree name, tree, int,
> >> + bool *no_add_attrs)
> >> +{
> >> + if (TREE_CODE (*node) != FUNCTION_DECL)
> >> + {
> >> + warning (OPT_Wattributes, "%qE attribute ignored", name);
> >> + *no_add_attrs = true;
> >> + }
> >> +
> >> + return NULL_TREE;
> >> +}
> >> +
> >> /* Handle an "asan odr indicator" attribute; arguments as in
> >> struct attribute_spec.handler. */
> >>
> >> diff --git a/gcc/doc/extend.texi b/gcc/doc/extend.texi
> >> index 826804e6149..3ddeb0dee3a 100644
> >> --- a/gcc/doc/extend.texi
> >> +++ b/gcc/doc/extend.texi
> >> @@ -3415,6 +3415,12 @@ The @code{no_sanitize_undefined} attribute on functions is used
> >> to inform the compiler that it should not check for undefined behavior
> >> in the function when compiling with the @option{-fsanitize=undefined} option.
> >>
> >> +@item no_sanitize_coverage
> >> +@cindex @code{no_sanitize_coverage} function attribute
> >> +The @code{no_sanitize_coverage} attribute on functions is used
> >> +to inform the compiler that it should not do coverage-guided
> >> +fuzzing code instrumentation (@option{-fsanitize-coverage}).
> >> +
> >> @item no_split_stack
> >> @cindex @code{no_split_stack} function attribute
> >> @opindex fsplit-stack
> >> diff --git a/gcc/fold-const.c b/gcc/fold-const.c
> >> index 3be9c15e6b2..d088187a057 100644
> >> --- a/gcc/fold-const.c
> >> +++ b/gcc/fold-const.c
> >> @@ -6016,7 +6016,7 @@ fold_range_test (location_t loc, enum tree_code code, tree type,
> >> logical_op_non_short_circuit
> >> = param_logical_op_non_short_circuit;
> >> if (logical_op_non_short_circuit
> >> - && !flag_sanitize_coverage
> >> + && !sanitize_coverage_p ()
> >> && lhs != 0 && rhs != 0
> >> && (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR)
> >> && operand_equal_p (lhs, rhs, 0))
> >> @@ -9652,7 +9652,7 @@ fold_truth_andor (location_t loc, enum tree_code code, tree type,
> >> logical_op_non_short_circuit
> >> = param_logical_op_non_short_circuit;
> >> if (logical_op_non_short_circuit
> >> - && !flag_sanitize_coverage
> >> + && !sanitize_coverage_p ()
> >> && (code == TRUTH_AND_EXPR
> >> || code == TRUTH_ANDIF_EXPR
> >> || code == TRUTH_OR_EXPR
> >> diff --git a/gcc/sancov.c b/gcc/sancov.c
> >> index d656c37cae9..9cfbd425def 100644
> >> --- a/gcc/sancov.c
> >> +++ b/gcc/sancov.c
> >> @@ -313,9 +313,9 @@ public:
> >> return new pass_sancov<O0> (m_ctxt);
> >> }
> >> virtual bool
> >> - gate (function *)
> >> + gate (function *fun)
> >> {
> >> - return flag_sanitize_coverage && (!O0 || !optimize);
> >> + return sanitize_coverage_p (fun->decl) && (!O0 || !optimize);
> >> }
> >> virtual unsigned int
> >> execute (function *fun)
> >> diff --git a/gcc/testsuite/gcc.dg/sancov/attribute.c b/gcc/testsuite/gcc.dg/sancov/attribute.c
> >> new file mode 100644
> >> index 00000000000..bf6dbd4bae7
> >> --- /dev/null
> >> +++ b/gcc/testsuite/gcc.dg/sancov/attribute.c
> >> @@ -0,0 +1,15 @@
> >> +/* { dg-do compile } */
> >> +/* { dg-options "-fsanitize-coverage=trace-pc -fdump-tree-optimized" } */
> >> +
> >> +void foo(void)
> >> +{
> >> +}
> >> +
> >> +void
> >> +__attribute__((no_sanitize_coverage))
> >> +bar(void)
> >> +{
> >> +}
> >> +
> >> +
> >> +/* { dg-final { scan-tree-dump-times "__builtin___sanitizer_cov_trace_pc \\(\\)" 1 "optimized" } } */
> >> diff --git a/gcc/tree-ssa-ifcombine.c b/gcc/tree-ssa-ifcombine.c
> >> index 836a12d6b80..f93e04aa4df 100644
> >> --- a/gcc/tree-ssa-ifcombine.c
> >> +++ b/gcc/tree-ssa-ifcombine.c
> >> @@ -40,6 +40,8 @@ along with GCC; see the file COPYING3. If not see
> >> #include "gimplify-me.h"
> >> #include "tree-cfg.h"
> >> #include "tree-ssa.h"
> >> +#include "attribs.h"
> >> +#include "asan.h"
> >>
> >> #ifndef LOGICAL_OP_NON_SHORT_CIRCUIT
> >> #define LOGICAL_OP_NON_SHORT_CIRCUIT \
> >> @@ -567,7 +569,7 @@ ifcombine_ifandif (basic_block inner_cond_bb, bool inner_inv,
> >> if (param_logical_op_non_short_circuit != -1)
> >> logical_op_non_short_circuit
> >> = param_logical_op_non_short_circuit;
> >> - if (!logical_op_non_short_circuit || flag_sanitize_coverage)
> >> + if (!logical_op_non_short_circuit || sanitize_coverage_p ())
> >> return false;
> >> /* Only do this optimization if the inner bb contains only the conditional. */
> >> if (!gsi_one_before_end_p (gsi_start_nondebug_after_labels_bb (inner_cond_bb)))
> >> --
> >> 2.31.1
> >>
>
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] Add no_sanitize_coverage attribute.
2021-05-20 10:55 ` Marco Elver
@ 2021-05-21 8:50 ` Martin Liška
2021-05-21 12:39 ` Marco Elver
0 siblings, 1 reply; 9+ messages in thread
From: Martin Liška @ 2021-05-21 8:50 UTC (permalink / raw)
To: Marco Elver; +Cc: GCC Patches, Nick Desaulniers
[-- Attachment #1: Type: text/plain, Size: 491 bytes --]
On 5/20/21 12:55 PM, Marco Elver wrote:
> I think this came up with other no_sanitize [1] based on what I had
> written to you last year [2].
>
> [1]https://gcc.gnu.org/pipermail/gcc-patches/2020-June/547618.html
> [2]https://lore.kernel.org/lkml/CANpmjNNRz5OVKb6PE7K6GjfoGbht_ZhyPkNG9aD+KjNDzK7hGg@mail.gmail.com/
Ah, you're right. I've just updated the patch to address that.
Patch can bootstrap on x86_64-linux-gnu and survives regression tests.
Ready to be installed?
Thanks,
Martin
[-- Attachment #2: 0001-Add-no_sanitize_coverage-attribute.patch --]
[-- Type: text/x-patch, Size: 7696 bytes --]
From b7f9f6c9722e7cb1b81b96ec646cadb5706b1038 Mon Sep 17 00:00:00 2001
From: Martin Liska <mliska@suse.cz>
Date: Thu, 20 May 2021 09:32:29 +0200
Subject: [PATCH] Add no_sanitize_coverage attribute.
gcc/ChangeLog:
* asan.h (sanitize_coverage_p): New function.
* doc/extend.texi: Document it.
* fold-const.c (fold_range_test): Use sanitize_flags_p
instead of flag_sanitize_coverage.
(fold_truth_andor): Likewise.
* sancov.c: Likewise.
* tree-ssa-ifcombine.c (ifcombine_ifandif): Likewise.
* ipa-inline.c (sanitize_attrs_match_for_inline_p): Handle
-fsanitize-coverage when inlining.
gcc/c-family/ChangeLog:
* c-attribs.c (handle_no_sanitize_coverage_attribute): New.
gcc/testsuite/ChangeLog:
* gcc.dg/sancov/attribute.c: New test.
---
gcc/asan.h | 10 ++++++++++
gcc/c-family/c-attribs.c | 20 ++++++++++++++++++++
gcc/doc/extend.texi | 6 ++++++
gcc/fold-const.c | 4 ++--
gcc/ipa-inline.c | 3 +++
gcc/sancov.c | 4 ++--
gcc/testsuite/gcc.dg/sancov/attribute.c | 15 +++++++++++++++
gcc/tree-ssa-ifcombine.c | 4 +++-
8 files changed, 61 insertions(+), 5 deletions(-)
create mode 100644 gcc/testsuite/gcc.dg/sancov/attribute.c
diff --git a/gcc/asan.h b/gcc/asan.h
index f110f1db563..8c0b2baf170 100644
--- a/gcc/asan.h
+++ b/gcc/asan.h
@@ -249,4 +249,14 @@ sanitize_flags_p (unsigned int flag, const_tree fn = current_function_decl)
return result_flags;
}
+/* Return true when coverage sanitization should happend for FN function. */
+
+static inline bool
+sanitize_coverage_p (const_tree fn = current_function_decl)
+{
+ return (flag_sanitize_coverage
+ && lookup_attribute ("no_sanitize_coverage",
+ DECL_ATTRIBUTES (fn)) == NULL_TREE);
+}
+
#endif /* TREE_ASAN */
diff --git a/gcc/c-family/c-attribs.c b/gcc/c-family/c-attribs.c
index ccf9e4ccf0b..671b27c3200 100644
--- a/gcc/c-family/c-attribs.c
+++ b/gcc/c-family/c-attribs.c
@@ -62,6 +62,8 @@ static tree handle_no_address_safety_analysis_attribute (tree *, tree, tree,
int, bool *);
static tree handle_no_sanitize_undefined_attribute (tree *, tree, tree, int,
bool *);
+static tree handle_no_sanitize_coverage_attribute (tree *, tree, tree, int,
+ bool *);
static tree handle_asan_odr_indicator_attribute (tree *, tree, tree, int,
bool *);
static tree handle_stack_protect_attribute (tree *, tree, tree, int, bool *);
@@ -449,6 +451,8 @@ const struct attribute_spec c_common_attribute_table[] =
handle_no_sanitize_thread_attribute, NULL },
{ "no_sanitize_undefined", 0, 0, true, false, false, false,
handle_no_sanitize_undefined_attribute, NULL },
+ { "no_sanitize_coverage", 0, 0, true, false, false, false,
+ handle_no_sanitize_coverage_attribute, NULL },
{ "asan odr indicator", 0, 0, true, false, false, false,
handle_asan_odr_indicator_attribute, NULL },
{ "warning", 1, 1, true, false, false, false,
@@ -1211,6 +1215,22 @@ handle_no_sanitize_undefined_attribute (tree *node, tree name, tree, int,
return NULL_TREE;
}
+/* Handle a "no_sanitize_coverage" attribute; arguments as in
+ struct attribute_spec.handler. */
+
+static tree
+handle_no_sanitize_coverage_attribute (tree *node, tree name, tree, int,
+ bool *no_add_attrs)
+{
+ if (TREE_CODE (*node) != FUNCTION_DECL)
+ {
+ warning (OPT_Wattributes, "%qE attribute ignored", name);
+ *no_add_attrs = true;
+ }
+
+ return NULL_TREE;
+}
+
/* Handle an "asan odr indicator" attribute; arguments as in
struct attribute_spec.handler. */
diff --git a/gcc/doc/extend.texi b/gcc/doc/extend.texi
index 826804e6149..3ddeb0dee3a 100644
--- a/gcc/doc/extend.texi
+++ b/gcc/doc/extend.texi
@@ -3415,6 +3415,12 @@ The @code{no_sanitize_undefined} attribute on functions is used
to inform the compiler that it should not check for undefined behavior
in the function when compiling with the @option{-fsanitize=undefined} option.
+@item no_sanitize_coverage
+@cindex @code{no_sanitize_coverage} function attribute
+The @code{no_sanitize_coverage} attribute on functions is used
+to inform the compiler that it should not do coverage-guided
+fuzzing code instrumentation (@option{-fsanitize-coverage}).
+
@item no_split_stack
@cindex @code{no_split_stack} function attribute
@opindex fsplit-stack
diff --git a/gcc/fold-const.c b/gcc/fold-const.c
index 3be9c15e6b2..d088187a057 100644
--- a/gcc/fold-const.c
+++ b/gcc/fold-const.c
@@ -6016,7 +6016,7 @@ fold_range_test (location_t loc, enum tree_code code, tree type,
logical_op_non_short_circuit
= param_logical_op_non_short_circuit;
if (logical_op_non_short_circuit
- && !flag_sanitize_coverage
+ && !sanitize_coverage_p ()
&& lhs != 0 && rhs != 0
&& (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR)
&& operand_equal_p (lhs, rhs, 0))
@@ -9652,7 +9652,7 @@ fold_truth_andor (location_t loc, enum tree_code code, tree type,
logical_op_non_short_circuit
= param_logical_op_non_short_circuit;
if (logical_op_non_short_circuit
- && !flag_sanitize_coverage
+ && !sanitize_coverage_p ()
&& (code == TRUTH_AND_EXPR
|| code == TRUTH_ANDIF_EXPR
|| code == TRUTH_OR_EXPR
diff --git a/gcc/ipa-inline.c b/gcc/ipa-inline.c
index f15c4828958..9d896beb2ac 100644
--- a/gcc/ipa-inline.c
+++ b/gcc/ipa-inline.c
@@ -283,6 +283,9 @@ sanitize_attrs_match_for_inline_p (const_tree caller, const_tree callee)
!= sanitize_flags_p (codes[i], callee))
return false;
+ if (sanitize_coverage_p (caller) != sanitize_coverage_p (callee))
+ return false;
+
return true;
}
diff --git a/gcc/sancov.c b/gcc/sancov.c
index d656c37cae9..9cfbd425def 100644
--- a/gcc/sancov.c
+++ b/gcc/sancov.c
@@ -313,9 +313,9 @@ public:
return new pass_sancov<O0> (m_ctxt);
}
virtual bool
- gate (function *)
+ gate (function *fun)
{
- return flag_sanitize_coverage && (!O0 || !optimize);
+ return sanitize_coverage_p (fun->decl) && (!O0 || !optimize);
}
virtual unsigned int
execute (function *fun)
diff --git a/gcc/testsuite/gcc.dg/sancov/attribute.c b/gcc/testsuite/gcc.dg/sancov/attribute.c
new file mode 100644
index 00000000000..bf6dbd4bae7
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/sancov/attribute.c
@@ -0,0 +1,15 @@
+/* { dg-do compile } */
+/* { dg-options "-fsanitize-coverage=trace-pc -fdump-tree-optimized" } */
+
+void foo(void)
+{
+}
+
+void
+__attribute__((no_sanitize_coverage))
+bar(void)
+{
+}
+
+
+/* { dg-final { scan-tree-dump-times "__builtin___sanitizer_cov_trace_pc \\(\\)" 1 "optimized" } } */
diff --git a/gcc/tree-ssa-ifcombine.c b/gcc/tree-ssa-ifcombine.c
index 836a12d6b80..f93e04aa4df 100644
--- a/gcc/tree-ssa-ifcombine.c
+++ b/gcc/tree-ssa-ifcombine.c
@@ -40,6 +40,8 @@ along with GCC; see the file COPYING3. If not see
#include "gimplify-me.h"
#include "tree-cfg.h"
#include "tree-ssa.h"
+#include "attribs.h"
+#include "asan.h"
#ifndef LOGICAL_OP_NON_SHORT_CIRCUIT
#define LOGICAL_OP_NON_SHORT_CIRCUIT \
@@ -567,7 +569,7 @@ ifcombine_ifandif (basic_block inner_cond_bb, bool inner_inv,
if (param_logical_op_non_short_circuit != -1)
logical_op_non_short_circuit
= param_logical_op_non_short_circuit;
- if (!logical_op_non_short_circuit || flag_sanitize_coverage)
+ if (!logical_op_non_short_circuit || sanitize_coverage_p ())
return false;
/* Only do this optimization if the inner bb contains only the conditional. */
if (!gsi_one_before_end_p (gsi_start_nondebug_after_labels_bb (inner_cond_bb)))
--
2.31.1
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] Add no_sanitize_coverage attribute.
2021-05-21 8:50 ` Martin Liška
@ 2021-05-21 12:39 ` Marco Elver
2021-05-24 8:03 ` Martin Liška
0 siblings, 1 reply; 9+ messages in thread
From: Marco Elver @ 2021-05-21 12:39 UTC (permalink / raw)
To: Martin Liška; +Cc: GCC Patches, Nick Desaulniers
On Fri, May 21, 2021 at 10:50AM +0200, Martin Liška wrote:
> On 5/20/21 12:55 PM, Marco Elver wrote:
> > I think this came up with other no_sanitize [1] based on what I had
> > written to you last year [2].
> >
> > [1]https://gcc.gnu.org/pipermail/gcc-patches/2020-June/547618.html
> > [2]https://lore.kernel.org/lkml/CANpmjNNRz5OVKb6PE7K6GjfoGbht_ZhyPkNG9aD+KjNDzK7hGg@mail.gmail.com/
>
> Ah, you're right. I've just updated the patch to address that.
>
> Patch can bootstrap on x86_64-linux-gnu and survives regression tests.
>
> Ready to be installed?
Looks good, I also just built a kernel with the no_sanitize_coverage
attribute (without the objtool nop-workaround) and works as expected.
Not sure if required, but would such an additional test be useful:
---
diff --git a/gcc/testsuite/gcc.dg/sancov/attribute.c b/gcc/testsuite/gcc.dg/sancov/attribute.c
index bf6dbd4bae7..7cfa9134ff1 100644
--- a/gcc/testsuite/gcc.dg/sancov/attribute.c
+++ b/gcc/testsuite/gcc.dg/sancov/attribute.c
@@ -11,5 +11,17 @@ bar(void)
{
}
+static void inline
+__attribute__((always_inline))
+inline_fn(void)
+{
+}
+
+void
+__attribute__((no_sanitize_coverage))
+baz(void)
+{
+ inline_fn();
+}
/* { dg-final { scan-tree-dump-times "__builtin___sanitizer_cov_trace_pc \\(\\)" 1 "optimized" } } */
---
Otherwise, please go ahead. I assume this is targeting GCC 12?
Thanks,
-- Marco
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] Add no_sanitize_coverage attribute.
2021-05-21 12:39 ` Marco Elver
@ 2021-05-24 8:03 ` Martin Liška
2021-05-24 8:07 ` Marco Elver
2021-05-25 9:55 ` Richard Biener
0 siblings, 2 replies; 9+ messages in thread
From: Martin Liška @ 2021-05-24 8:03 UTC (permalink / raw)
To: Marco Elver; +Cc: GCC Patches, Nick Desaulniers
[-- Attachment #1: Type: text/plain, Size: 1621 bytes --]
On 5/21/21 2:39 PM, Marco Elver wrote:
> On Fri, May 21, 2021 at 10:50AM +0200, Martin Liška wrote:
>> On 5/20/21 12:55 PM, Marco Elver wrote:
>>> I think this came up with other no_sanitize [1] based on what I had
>>> written to you last year [2].
>>>
>>> [1]https://gcc.gnu.org/pipermail/gcc-patches/2020-June/547618.html
>>> [2]https://lore.kernel.org/lkml/CANpmjNNRz5OVKb6PE7K6GjfoGbht_ZhyPkNG9aD+KjNDzK7hGg@mail.gmail.com/
>>
>> Ah, you're right. I've just updated the patch to address that.
>>
>> Patch can bootstrap on x86_64-linux-gnu and survives regression tests.
>>
>> Ready to be installed?
>
> Looks good, I also just built a kernel with the no_sanitize_coverage
> attribute (without the objtool nop-workaround) and works as expected.
Good, thanks!
>
> Not sure if required, but would such an additional test be useful:
Yes, it is, thanks for it.
>
> ---
>
> diff --git a/gcc/testsuite/gcc.dg/sancov/attribute.c b/gcc/testsuite/gcc.dg/sancov/attribute.c
> index bf6dbd4bae7..7cfa9134ff1 100644
> --- a/gcc/testsuite/gcc.dg/sancov/attribute.c
> +++ b/gcc/testsuite/gcc.dg/sancov/attribute.c
> @@ -11,5 +11,17 @@ bar(void)
> {
> }
>
> +static void inline
> +__attribute__((always_inline))
> +inline_fn(void)
> +{
> +}
> +
> +void
> +__attribute__((no_sanitize_coverage))
> +baz(void)
> +{
> + inline_fn();
> +}
>
> /* { dg-final { scan-tree-dump-times "__builtin___sanitizer_cov_trace_pc \\(\\)" 1 "optimized" } } */
>
> ---
>
> Otherwise, please go ahead. I assume this is targeting GCC 12?
Yep.
There's V3 I'm sending.
Ready for master?
Thanks,
Martin
>
> Thanks,
> -- Marco
>
[-- Attachment #2: 0001-Add-no_sanitize_coverage-attribute.patch --]
[-- Type: text/x-patch, Size: 7858 bytes --]
From 15053b32a870cd62641ad62a9e76a78558489f4a Mon Sep 17 00:00:00 2001
From: Martin Liska <mliska@suse.cz>
Date: Thu, 20 May 2021 09:32:29 +0200
Subject: [PATCH] Add no_sanitize_coverage attribute.
gcc/ChangeLog:
* asan.h (sanitize_coverage_p): New function.
* doc/extend.texi: Document it.
* fold-const.c (fold_range_test): Use sanitize_flags_p
instead of flag_sanitize_coverage.
(fold_truth_andor): Likewise.
* sancov.c: Likewise.
* tree-ssa-ifcombine.c (ifcombine_ifandif): Likewise.
* ipa-inline.c (sanitize_attrs_match_for_inline_p): Handle
-fsanitize-coverage when inlining.
gcc/c-family/ChangeLog:
* c-attribs.c (handle_no_sanitize_coverage_attribute): New.
gcc/testsuite/ChangeLog:
* gcc.dg/sancov/attribute.c: New test.
---
gcc/asan.h | 10 +++++++++
gcc/c-family/c-attribs.c | 20 ++++++++++++++++++
gcc/doc/extend.texi | 6 ++++++
gcc/fold-const.c | 4 ++--
gcc/ipa-inline.c | 3 +++
gcc/sancov.c | 4 ++--
gcc/testsuite/gcc.dg/sancov/attribute.c | 27 +++++++++++++++++++++++++
gcc/tree-ssa-ifcombine.c | 4 +++-
8 files changed, 73 insertions(+), 5 deletions(-)
create mode 100644 gcc/testsuite/gcc.dg/sancov/attribute.c
diff --git a/gcc/asan.h b/gcc/asan.h
index f110f1db563..8c0b2baf170 100644
--- a/gcc/asan.h
+++ b/gcc/asan.h
@@ -249,4 +249,14 @@ sanitize_flags_p (unsigned int flag, const_tree fn = current_function_decl)
return result_flags;
}
+/* Return true when coverage sanitization should happend for FN function. */
+
+static inline bool
+sanitize_coverage_p (const_tree fn = current_function_decl)
+{
+ return (flag_sanitize_coverage
+ && lookup_attribute ("no_sanitize_coverage",
+ DECL_ATTRIBUTES (fn)) == NULL_TREE);
+}
+
#endif /* TREE_ASAN */
diff --git a/gcc/c-family/c-attribs.c b/gcc/c-family/c-attribs.c
index ccf9e4ccf0b..671b27c3200 100644
--- a/gcc/c-family/c-attribs.c
+++ b/gcc/c-family/c-attribs.c
@@ -62,6 +62,8 @@ static tree handle_no_address_safety_analysis_attribute (tree *, tree, tree,
int, bool *);
static tree handle_no_sanitize_undefined_attribute (tree *, tree, tree, int,
bool *);
+static tree handle_no_sanitize_coverage_attribute (tree *, tree, tree, int,
+ bool *);
static tree handle_asan_odr_indicator_attribute (tree *, tree, tree, int,
bool *);
static tree handle_stack_protect_attribute (tree *, tree, tree, int, bool *);
@@ -449,6 +451,8 @@ const struct attribute_spec c_common_attribute_table[] =
handle_no_sanitize_thread_attribute, NULL },
{ "no_sanitize_undefined", 0, 0, true, false, false, false,
handle_no_sanitize_undefined_attribute, NULL },
+ { "no_sanitize_coverage", 0, 0, true, false, false, false,
+ handle_no_sanitize_coverage_attribute, NULL },
{ "asan odr indicator", 0, 0, true, false, false, false,
handle_asan_odr_indicator_attribute, NULL },
{ "warning", 1, 1, true, false, false, false,
@@ -1211,6 +1215,22 @@ handle_no_sanitize_undefined_attribute (tree *node, tree name, tree, int,
return NULL_TREE;
}
+/* Handle a "no_sanitize_coverage" attribute; arguments as in
+ struct attribute_spec.handler. */
+
+static tree
+handle_no_sanitize_coverage_attribute (tree *node, tree name, tree, int,
+ bool *no_add_attrs)
+{
+ if (TREE_CODE (*node) != FUNCTION_DECL)
+ {
+ warning (OPT_Wattributes, "%qE attribute ignored", name);
+ *no_add_attrs = true;
+ }
+
+ return NULL_TREE;
+}
+
/* Handle an "asan odr indicator" attribute; arguments as in
struct attribute_spec.handler. */
diff --git a/gcc/doc/extend.texi b/gcc/doc/extend.texi
index 826804e6149..3ddeb0dee3a 100644
--- a/gcc/doc/extend.texi
+++ b/gcc/doc/extend.texi
@@ -3415,6 +3415,12 @@ The @code{no_sanitize_undefined} attribute on functions is used
to inform the compiler that it should not check for undefined behavior
in the function when compiling with the @option{-fsanitize=undefined} option.
+@item no_sanitize_coverage
+@cindex @code{no_sanitize_coverage} function attribute
+The @code{no_sanitize_coverage} attribute on functions is used
+to inform the compiler that it should not do coverage-guided
+fuzzing code instrumentation (@option{-fsanitize-coverage}).
+
@item no_split_stack
@cindex @code{no_split_stack} function attribute
@opindex fsplit-stack
diff --git a/gcc/fold-const.c b/gcc/fold-const.c
index 3be9c15e6b2..d088187a057 100644
--- a/gcc/fold-const.c
+++ b/gcc/fold-const.c
@@ -6016,7 +6016,7 @@ fold_range_test (location_t loc, enum tree_code code, tree type,
logical_op_non_short_circuit
= param_logical_op_non_short_circuit;
if (logical_op_non_short_circuit
- && !flag_sanitize_coverage
+ && !sanitize_coverage_p ()
&& lhs != 0 && rhs != 0
&& (code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR)
&& operand_equal_p (lhs, rhs, 0))
@@ -9652,7 +9652,7 @@ fold_truth_andor (location_t loc, enum tree_code code, tree type,
logical_op_non_short_circuit
= param_logical_op_non_short_circuit;
if (logical_op_non_short_circuit
- && !flag_sanitize_coverage
+ && !sanitize_coverage_p ()
&& (code == TRUTH_AND_EXPR
|| code == TRUTH_ANDIF_EXPR
|| code == TRUTH_OR_EXPR
diff --git a/gcc/ipa-inline.c b/gcc/ipa-inline.c
index f15c4828958..9d896beb2ac 100644
--- a/gcc/ipa-inline.c
+++ b/gcc/ipa-inline.c
@@ -283,6 +283,9 @@ sanitize_attrs_match_for_inline_p (const_tree caller, const_tree callee)
!= sanitize_flags_p (codes[i], callee))
return false;
+ if (sanitize_coverage_p (caller) != sanitize_coverage_p (callee))
+ return false;
+
return true;
}
diff --git a/gcc/sancov.c b/gcc/sancov.c
index d656c37cae9..9cfbd425def 100644
--- a/gcc/sancov.c
+++ b/gcc/sancov.c
@@ -313,9 +313,9 @@ public:
return new pass_sancov<O0> (m_ctxt);
}
virtual bool
- gate (function *)
+ gate (function *fun)
{
- return flag_sanitize_coverage && (!O0 || !optimize);
+ return sanitize_coverage_p (fun->decl) && (!O0 || !optimize);
}
virtual unsigned int
execute (function *fun)
diff --git a/gcc/testsuite/gcc.dg/sancov/attribute.c b/gcc/testsuite/gcc.dg/sancov/attribute.c
new file mode 100644
index 00000000000..7cfa9134ff1
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/sancov/attribute.c
@@ -0,0 +1,27 @@
+/* { dg-do compile } */
+/* { dg-options "-fsanitize-coverage=trace-pc -fdump-tree-optimized" } */
+
+void foo(void)
+{
+}
+
+void
+__attribute__((no_sanitize_coverage))
+bar(void)
+{
+}
+
+static void inline
+__attribute__((always_inline))
+inline_fn(void)
+{
+}
+
+void
+__attribute__((no_sanitize_coverage))
+baz(void)
+{
+ inline_fn();
+}
+
+/* { dg-final { scan-tree-dump-times "__builtin___sanitizer_cov_trace_pc \\(\\)" 1 "optimized" } } */
diff --git a/gcc/tree-ssa-ifcombine.c b/gcc/tree-ssa-ifcombine.c
index 836a12d6b80..f93e04aa4df 100644
--- a/gcc/tree-ssa-ifcombine.c
+++ b/gcc/tree-ssa-ifcombine.c
@@ -40,6 +40,8 @@ along with GCC; see the file COPYING3. If not see
#include "gimplify-me.h"
#include "tree-cfg.h"
#include "tree-ssa.h"
+#include "attribs.h"
+#include "asan.h"
#ifndef LOGICAL_OP_NON_SHORT_CIRCUIT
#define LOGICAL_OP_NON_SHORT_CIRCUIT \
@@ -567,7 +569,7 @@ ifcombine_ifandif (basic_block inner_cond_bb, bool inner_inv,
if (param_logical_op_non_short_circuit != -1)
logical_op_non_short_circuit
= param_logical_op_non_short_circuit;
- if (!logical_op_non_short_circuit || flag_sanitize_coverage)
+ if (!logical_op_non_short_circuit || sanitize_coverage_p ())
return false;
/* Only do this optimization if the inner bb contains only the conditional. */
if (!gsi_one_before_end_p (gsi_start_nondebug_after_labels_bb (inner_cond_bb)))
--
2.31.1
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] Add no_sanitize_coverage attribute.
2021-05-24 8:03 ` Martin Liška
@ 2021-05-24 8:07 ` Marco Elver
2021-05-25 9:55 ` Richard Biener
1 sibling, 0 replies; 9+ messages in thread
From: Marco Elver @ 2021-05-24 8:07 UTC (permalink / raw)
To: Martin Liška; +Cc: GCC Patches, Nick Desaulniers
On Mon, 24 May 2021 at 10:03, Martin Liška <mliska@suse.cz> wrote:
> On 5/21/21 2:39 PM, Marco Elver wrote:
> > On Fri, May 21, 2021 at 10:50AM +0200, Martin Liška wrote:
> >> On 5/20/21 12:55 PM, Marco Elver wrote:
> >>> I think this came up with other no_sanitize [1] based on what I had
> >>> written to you last year [2].
> >>>
> >>> [1]https://gcc.gnu.org/pipermail/gcc-patches/2020-June/547618.html
> >>> [2]https://lore.kernel.org/lkml/CANpmjNNRz5OVKb6PE7K6GjfoGbht_ZhyPkNG9aD+KjNDzK7hGg@mail.gmail.com/
> >>
> >> Ah, you're right. I've just updated the patch to address that.
> >>
> >> Patch can bootstrap on x86_64-linux-gnu and survives regression tests.
> >>
> >> Ready to be installed?
> >
> > Looks good, I also just built a kernel with the no_sanitize_coverage
> > attribute (without the objtool nop-workaround) and works as expected.
>
> Good, thanks!
>
> >
> > Not sure if required, but would such an additional test be useful:
>
> Yes, it is, thanks for it.
[...]
> > Otherwise, please go ahead. I assume this is targeting GCC 12?
>
> Yep.
>
> There's V3 I'm sending.
>
> Ready for master?
From my side this looks good. Thank you!
-- Marco
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] Add no_sanitize_coverage attribute.
2021-05-24 8:03 ` Martin Liška
2021-05-24 8:07 ` Marco Elver
@ 2021-05-25 9:55 ` Richard Biener
1 sibling, 0 replies; 9+ messages in thread
From: Richard Biener @ 2021-05-25 9:55 UTC (permalink / raw)
To: Martin Liška; +Cc: Marco Elver, Nick Desaulniers, GCC Patches
On Mon, May 24, 2021 at 10:27 AM Martin Liška <mliska@suse.cz> wrote:
>
> On 5/21/21 2:39 PM, Marco Elver wrote:
> > On Fri, May 21, 2021 at 10:50AM +0200, Martin Liška wrote:
> >> On 5/20/21 12:55 PM, Marco Elver wrote:
> >>> I think this came up with other no_sanitize [1] based on what I had
> >>> written to you last year [2].
> >>>
> >>> [1]https://gcc.gnu.org/pipermail/gcc-patches/2020-June/547618.html
> >>> [2]https://lore.kernel.org/lkml/CANpmjNNRz5OVKb6PE7K6GjfoGbht_ZhyPkNG9aD+KjNDzK7hGg@mail.gmail.com/
> >>
> >> Ah, you're right. I've just updated the patch to address that.
> >>
> >> Patch can bootstrap on x86_64-linux-gnu and survives regression tests.
> >>
> >> Ready to be installed?
> >
> > Looks good, I also just built a kernel with the no_sanitize_coverage
> > attribute (without the objtool nop-workaround) and works as expected.
>
> Good, thanks!
>
> >
> > Not sure if required, but would such an additional test be useful:
>
> Yes, it is, thanks for it.
>
> >
> > ---
> >
> > diff --git a/gcc/testsuite/gcc.dg/sancov/attribute.c b/gcc/testsuite/gcc.dg/sancov/attribute.c
> > index bf6dbd4bae7..7cfa9134ff1 100644
> > --- a/gcc/testsuite/gcc.dg/sancov/attribute.c
> > +++ b/gcc/testsuite/gcc.dg/sancov/attribute.c
> > @@ -11,5 +11,17 @@ bar(void)
> > {
> > }
> >
> > +static void inline
> > +__attribute__((always_inline))
> > +inline_fn(void)
> > +{
> > +}
> > +
> > +void
> > +__attribute__((no_sanitize_coverage))
> > +baz(void)
> > +{
> > + inline_fn();
> > +}
> >
> > /* { dg-final { scan-tree-dump-times "__builtin___sanitizer_cov_trace_pc \\(\\)" 1 "optimized" } } */
> >
> > ---
> >
> > Otherwise, please go ahead. I assume this is targeting GCC 12?
>
> Yep.
>
> There's V3 I'm sending.
>
> Ready for master?
OK.
Thanks,
Richard.
> Thanks,
> Martin
>
> >
> > Thanks,
> > -- Marco
> >
>
^ permalink raw reply [flat|nested] 9+ messages in thread
end of thread, other threads:[~2021-05-25 9:55 UTC | newest]
Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-05-20 8:33 [PATCH] Add no_sanitize_coverage attribute Martin Liška
2021-05-20 8:45 ` Marco Elver
2021-05-20 9:08 ` Martin Liška
2021-05-20 10:55 ` Marco Elver
2021-05-21 8:50 ` Martin Liška
2021-05-21 12:39 ` Marco Elver
2021-05-24 8:03 ` Martin Liška
2021-05-24 8:07 ` Marco Elver
2021-05-25 9:55 ` Richard Biener
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