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
