The reason is that test coverage is using the same underlying
profiling. Returning false when calling '__gcov_profiling_enabled())
in coverage mode is a little misleading.
David
On Wed, Jul 2, 2014 at 1:22 PM, Teresa Johnson <tejohn...@google.com> wrote:
> On Wed, Jul 2, 2014 at 1:15 PM, Xinliang David Li <davi...@google.com> wrote:
>> Should the interface be something like:
>>
>> int __gcov_profiling_for_test_coverage(void)?
>
> I was equating the term "profiling" with -fprofile-generate, as
> opposed to -ftest-coverage instrumentation. But I can change it to
> this if you think that is clearer.
>
> Teresa
>
>>
>> David
>>
>>
>> On Wed, Jul 2, 2014 at 12:55 PM, Teresa Johnson <tejohn...@google.com> wrote:
>>> The following patch adds support for a new libgcov interface,
>>> __gcov_profiling_enabled, that can be used by applications to
>>> determine whether a binary has been instrumented for test coverage or
>>> profile optimization.
>>>
>>> Passes regression tests and manual testing with different options. Ok
>>> for google branches?
>>>
>>> Thanks,
>>> Teresa
>>>
>>> 2014-07-02 Teresa Johnson <tejohn...@google.com>
>>>
>>> Google ref b/15378201.
>>> * gcc/tree-profile.c (gcov_test_coverage_decl): Declare.
>>> (tree_init_instrumentation): Initialize gcov_test_coverage_decl.
>>> * libgcc/libgcov-driver.c (__gcov_dummy_ref7): Define.
>>> * libgcc/libgcov-interface.c (__gcov_profiling_enabled): New
>>> function.
>>>
>>> Index: gcc/tree-profile.c
>>> ===================================================================
>>> --- gcc/tree-profile.c (revision 212044)
>>> +++ gcc/tree-profile.c (working copy)
>>> @@ -164,6 +164,9 @@ static GTY(()) tree gcov_sample_counter_decl = NUL
>>> /* extern gcov_unsigned_t __gcov_profile_prefix */
>>> static tree GTY(()) gcov_profile_prefix_decl = NULL_TREE;
>>>
>>> +/* extern gcov_unsigned_t __gcov_test_coverage */
>>> +static tree GTY(()) gcov_test_coverage_decl = NULL_TREE;
>>> +
>>> /* extern gcov_unsigned_t __gcov_sampling_period */
>>> static GTY(()) tree gcov_sampling_period_decl = NULL_TREE;
>>>
>>> @@ -498,6 +501,27 @@ tree_init_instrumentation (void)
>>> DECL_INITIAL (gcov_profile_prefix_decl) = prefix_ptr;
>>> varpool_finalize_decl (gcov_profile_prefix_decl);
>>> }
>>> +
>>> + if (!gcov_test_coverage_decl)
>>> + {
>>> + /* Initialize __gcov_test_coverage to 1 if -ftest-coverage
>>> + specified, 0 otherwise. Used by libgcov to determine whether
>>> + a binary was instrumented for coverage or profile optimization.
>>> */
>>> + gcov_test_coverage_decl = build_decl (
>>> + UNKNOWN_LOCATION,
>>> + VAR_DECL,
>>> + get_identifier ("__gcov_test_coverage"),
>>> + get_gcov_unsigned_t ());
>>> + TREE_PUBLIC (gcov_test_coverage_decl) = 1;
>>> + DECL_ARTIFICIAL (gcov_test_coverage_decl) = 1;
>>> + DECL_COMDAT_GROUP (gcov_test_coverage_decl)
>>> + = DECL_ASSEMBLER_NAME (gcov_test_coverage_decl);
>>> + TREE_STATIC (gcov_test_coverage_decl) = 1;
>>> + DECL_INITIAL (gcov_test_coverage_decl) = build_int_cst (
>>> + get_gcov_unsigned_t (),
>>> + flag_test_coverage ? 1 : 0);
>>> + varpool_finalize_decl (gcov_test_coverage_decl);
>>> + }
>>> }
>>>
>>> /* Initialization function for FDO sampling. */
>>> Index: libgcc/libgcov-driver.c
>>> ===================================================================
>>> --- libgcc/libgcov-driver.c (revision 212044)
>>> +++ libgcc/libgcov-driver.c (working copy)
>>> @@ -79,6 +79,8 @@ extern unsigned int __gcov_sampling_enabled (void)
>>> char *(*__gcov_dummy_ref5)(void) = &__gcov_sampling_enabled;
>>> extern void __gcov_flush (void);
>>> char *(*__gcov_dummy_ref6)(void) = &__gcov_flush;
>>> +extern unsigned int __gcov_profiling_enabled (void);
>>> +char *(*__gcov_dummy_ref7)(void) = &__gcov_profiling_enabled;
>>>
>>> /* Default callback function for profile instrumentation callback. */
>>> extern void __coverage_callback (gcov_type, int);
>>> Index: libgcc/libgcov-interface.c
>>> ===================================================================
>>> --- libgcc/libgcov-interface.c (revision 212044)
>>> +++ libgcc/libgcov-interface.c (working copy)
>>> @@ -116,6 +116,20 @@ __gcov_dump (void)
>>> set_gcov_dump_complete ();
>>> }
>>>
>>> +/* Emitted in coverage.c. */
>>> +extern gcov_unsigned_t __gcov_test_coverage;
>>> +
>>> +unsigned int __gcov_profiling_enabled (void);
>>> +
>>> +/* Function that can be called from application to distinguish binaries
>>> + instrumented from coverage fro those instrumented for profiling
>>> + (e.g. -fprofile-generate). */
>>> +
>>> +unsigned int __gcov_profiling_enabled (void)
>>> +{
>>> + return !__gcov_test_coverage;
>>> +}
>>> +
>>> #endif /* L_gcov_dump */
>>>
>>> #ifdef L_gcov_sampling
>>>
>>>
>>> --
>>> Teresa Johnson | Software Engineer | tejohn...@google.com | 408-460-2413
>
>
>
> --
> Teresa Johnson | Software Engineer | tejohn...@google.com | 408-460-2413
