Add selftests run filtering

With the growing number of selftests, I think it would be useful to be
able to run only a subset of the tests.  This patch associates a name to
each registered selftest.  It then allows doing something like:

  (gdb) maintenance selftest aarch64
  Running self-tests.
  Running selftest aarch64-analyze-prologue.
  Running selftest aarch64-process-record.
  Ran 2 unit tests, 0 failed

or with gdbserver:

  ./gdbserver --selftest=aarch64

In both cases, only the tests that contain "aarch64" in their name are
ran.  To help validate that the tests you want to run were actually ran,
it also prints a message with the test name before running each test.

Right now, all the arch-dependent tests are registered as a single test
of the selftests.  To be able to filter those too, I made them
"first-class citizen" selftests.  The selftest type is an interface,
with different implementations for "simple selftests" and "arch
selftests".  The run_tests function simply iterates on that an invokes
operator() on each test.

I changed the tests data structure from a vector to a map, because

  - it allows iterating in a stable (alphabetical) order
  - it allows to easily verify if a test with a given name has been
    registered, to avoid duplicates

There's also a new command "maintenance info selftests" that lists the
registered selftests.

gdb/ChangeLog:

	* common/selftest.h (selftest): New struct/interface.
	(register_test): Add name parameter, add new overload.
	(run_tests): Add filter parameter.
	(for_each_selftest_ftype): New typedef.
	(for_each_selftest): New declaration.
	* common/selftest.c (tests): Change type to
	map<string, unique_ptr<selftest>>.
	(simple_selftest): New struct.
	(register_test): New function.
	(register_test): Add name parameter and use it.
	(run_tests): Add filter parameter and use it.  Add prints.
	Adjust to vector -> map change.
	* aarch64-tdep.c (_initialize_aarch64_tdep): Add names when
	registering selftests.
	* arm-tdep.c (_initialize_arm_tdep): Likewise.
	* disasm-selftests.c (_initialize_disasm_selftests): Likewise.
	* dwarf2-frame.c (_initialize_dwarf2_frame): Likewise.
	* dwarf2loc.c (_initialize_dwarf2loc): Likewise.
	* findvar.c (_initialize_findvar): Likewise.
	* gdbarch-selftests.c (_initialize_gdbarch_selftests): Likewise.
	* maint.c (maintenance_selftest): Update call to run_tests.
	(maintenance_info_selftests): New function.
	(_initialize_maint_cmds): Register "maintenance info selftests"
	command.  Update "maintenance selftest" doc.
	* regcache.c (_initialize_regcache): Add names when registering
	selftests.
	* rust-exp.y (_initialize_rust_exp): Likewise.
	* selftest-arch.c (gdbarch_selftest): New struct.
	(gdbarch_tests): Remove.
	(register_test_foreach_arch): Add name parameter.  Call
	register_test.
	(tests_with_arch): Remove, move most content to
	gdbarch_selftest::operator().
	(_initialize_selftests_foreach_arch): Remove.
	* selftest-arch.h (register_test_foreach_arch): Add name
	parameter.
	(run_tests_with_arch): New declaration.
	* utils-selftests.c (_initialize_utils_selftests): Add names
	when registering selftests.
	* utils.c (_initialize_utils): Likewise.
	* unittests/array-view-selftests.c
	(_initialize_array_view_selftests): Likewise.
	* unittests/environ-selftests.c (_initialize_environ_selftests):
	Likewise.
	* unittests/function-view-selftests.c
	(_initialize_function_view_selftests): Likewise.
	* unittests/offset-type-selftests.c
	(_initialize_offset_type_selftests): Likewise.
	* unittests/optional-selftests.c
	(_initialize_optional_selftests): Likewise.
	* unittests/scoped_restore-selftests.c
	(_initialize_scoped_restore_selftests): Likewise.
	* NEWS: Document "maintenance selftest" and "maint info
	selftests".

gdb/gdbserver/ChangeLog:

	* server.c (captured_main): Accept argument for --selftest.
	Update run_tests call.
	* linux-x86-tdesc-selftest.c (initialize_low_tdesc): Add names
	when registering selftests.

gdb/doc/ChangeLog:

	* gdb.texinfo (Maintenance Commands): Document filter parameter
	of "maint selftest".  Document "maint info selftests" command.

2 files changed, 80 insertions, 14 deletions

diff --git a/gdb/common/selftest.c b/gdb/common/selftest.c
index 0fb8f2a..6518e58 100644
--- a/gdb/common/selftest.c
+++ b/gdb/common/selftest.c
@@ -20,35 +20,72 @@
 #include "common-exceptions.h"
 #include "common-debug.h"
 #include "selftest.h"
-#include <vector>
+#include <map>
 
 namespace selftests
 {
+/* All the tests that have been registered.  Using an std::map allows keeping
+   the order of tests stable and easily looking up whether a test name
+   exists.  */
 
-/* All the tests that have been registered.  */
+static std::map<std::string, std::unique_ptr<selftest>> tests;
 
-static std::vector<self_test_function *> tests;
+/* A selftest that calls the test function without arguments.  */
+
+struct simple_selftest : public selftest
+{
+  simple_selftest (self_test_function *function_)
+  : function (function_)
+  {}
+
+  void operator() () const override
+  {
+    function ();
+  }
+
+  self_test_function *function;
+};
 
 /* See selftest.h.  */
 
 void
-register_test (self_test_function *function)
+register_test (const std::string &name, selftest *test)
 {
-  tests.push_back (function);
+  /* Check that no test with this name already exist.  */
+  gdb_assert (tests.find (name) == tests.end ());
+
+  tests[name] = std::unique_ptr<selftest> (test);
 }
 
 /* See selftest.h.  */
 
 void
-run_tests (void)
+register_test (const std::string &name, self_test_function *function)
 {
-  int failed = 0;
+  register_test (name, new simple_selftest (function));
+}
+
+/* See selftest.h.  */
 
-  for (int i = 0; i < tests.size (); ++i)
+void
+run_tests (const char *filter)
+{
+  int ran = 0, failed = 0;
+
+  for (const auto &pair : tests)
     {
+      const std::string &name = pair.first;
+      const std::unique_ptr<selftest> &test = pair.second;
+
+      if (filter != NULL && *filter != '\0'
+	  && name.find (filter) == std::string::npos)
+	continue;
+
       TRY
 	{
-	  tests[i] ();
+	  debug_printf (_("Running selftest %s.\n"), name.c_str ());
+	  ++ran;
+	  (*test) ();
 	}
       CATCH (ex, RETURN_MASK_ERROR)
 	{
@@ -60,7 +97,16 @@ run_tests (void)
       reset ();
     }
 
-  debug_printf ("Ran %lu unit tests, %d failed\n",
-		(long) tests.size (), failed);
+  debug_printf (_("Ran %d unit tests, %d failed\n"),
+		ran, failed);
 }
+
+/* See selftest.h.  */
+
+void for_each_selftest (for_each_selftest_ftype func)
+{
+  for (const auto &pair : tests)
+    func (pair.first);
+}
+
 } // namespace selftests
diff --git a/gdb/common/selftest.h b/gdb/common/selftest.h
index e211c34..35a344f 100644
--- a/gdb/common/selftest.h
+++ b/gdb/common/selftest.h
@@ -27,18 +27,38 @@ typedef void self_test_function (void);
 namespace selftests
 {
 
+/* Interface for the various kinds of selftests.  */
+
+struct selftest
+{
+  virtual void operator() () const = 0;
+};
+
 /* Register a new self-test.  */
 
-extern void register_test (self_test_function *function);
+extern void register_test (const std::string &name, selftest *test);
+
+/* Register a new self-test.  */
+
+extern void register_test (const std::string &name,
+			   self_test_function *function);
 
 /* Run all the self tests.  This print a message describing the number
-   of test and the number of failures.  */
+   of test and the number of failures.
+
+   If FILTER is not NULL and not empty, only tests with names containing FILTER
+   will be ran.  */
 
-extern void run_tests (void);
+extern void run_tests (const char *filter);
 
 /* Reset GDB or GDBserver's internal state.  */
 extern void reset ();
 
+typedef void for_each_selftest_ftype (const std::string &name);
+
+/* Call FUNC for each registered selftest.  */
+
+extern void for_each_selftest (for_each_selftest_ftype func);
 }
 
 /* Check that VALUE is true, and, if not, throw an exception.  */