Add gmonster-{1,2} perf testcases.

These testcases are mocks of real programs.
GDB doesn't care what the programs do, they just have to look
and/or behave like the real program.
These testcases exercise gdb when debugging really large programs.
E.g., gmonster-1 has 10,000 CUs, and gmonster-2 has 1000 shared libs
(which is actually a little small, 5000 would be more accurate).

gdb/testsuite/ChangeLog:

	* gdb.perf/lib/perftest/utils.py: New file.
	* gdb.perf/gm-hello.cc: New file.
	* gdb.perf/gm-pervasive-typedef.cc: New file.
	* gdb.perf/gm-pervasive-typedef.h: New file.
	* gdb.perf/gm-std.cc: New file.
	* gdb.perf/gm-std.h: New file.
	* gdb.perf/gm-use-cerr.cc: New file.
	* gdb.perf/gm-utils.h: New file.
	* gdb.perf/gmonster-null-lookup.py: New file.
	* gdb.perf/gmonster-pervasive-typedef.py: New file.
	* gdb.perf/gmonster-print-cerr.py: New file.
	* gdb.perf/gmonster-ptype-string.py: New file.
	* gdb.perf/gmonster-runto-main.py: New file.
	* gdb.perf/gmonster-select-file.py: New file.
	* gdb.perf/gmonster1-null-lookup.exp: New file.
	* gdb.perf/gmonster1-pervasive-typedef.exp: New file.
	* gdb.perf/gmonster1-print-cerr.exp: New file.
	* gdb.perf/gmonster1-ptype-string.exp: New file.
	* gdb.perf/gmonster1-runto-main.exp: New file.
	* gdb.perf/gmonster1-select-file.exp: New file.
	* gdb.perf/gmonster1.cc: New file.
	* gdb.perf/gmonster1.exp: New file.
	* gdb.perf/gmonster2-null-lookup.exp: New file.
	* gdb.perf/gmonster2-pervasive-typedef.exp: New file.
	* gdb.perf/gmonster2-print-cerr.exp: New file.
	* gdb.perf/gmonster2-ptype-string.exp: New file.
	* gdb.perf/gmonster2-runto-main.exp: New file.
	* gdb.perf/gmonster2-select-file.exp: New file.
	* gdb.perf/gmonster2.cc: New file.
	* gdb.perf/gmonster2.exp: New file.

gdb/testsuite/gdb.perf/gmonster-select-file.py

@@ -0,0 +1,43 @@
+# Copyright (C) 2015 Free Software Foundation, Inc.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+# Measure performance of selecting a file to debug.
+
+from perftest import perftest
+from perftest import measure
+from perftest import utils
+
+class GmonsterSelectFile(perftest.TestCaseWithBasicMeasurements):
+    def __init__(self, name, run_names, binfile):
+        super(GmonsterSelectFile, self).__init__(name)
+        self.run_names = run_names
+        self.binfile = binfile
+
+    def warm_up(self):
+        pass
+
+    def _doit(self, binfile):
+        utils.select_file(None)
+        utils.select_file(binfile)
+
+    def execute_test(self):
+        for run in self.run_names:
+            this_run_binfile = "%s-%s" % (self.binfile,
+                                          utils.convert_spaces(run))
+            iteration = 5
+            while iteration > 0:
+                func = lambda: self._doit(this_run_binfile)
+                self.measure.measure(func, run)
+                iteration -= 1