GDB perf test on single step

gdb/testsuite:

2013-11-24  Yao Qi  <yao@codesourcery.com>

	* gdb.perf/single-step.c: New.
	* gdb.perf/single-step.exp: New.
	* gdb.perf/single-step.py: New.

gdb/testsuite/ChangeLog

@@ -1,3 +1,9 @@
+2013-11-24  Yao Qi  <yao@codesourcery.com>
+
+	* gdb.perf/single-step.c: New.
+	* gdb.perf/single-step.exp: New.
+	* gdb.perf/single-step.py: New.
+
 2013-11-23  Doug Evans  <xdje42@gmail.com>
 
 	* gdb.base/ena-dis-br.exp: Add missing quote to "step after continue

gdb/testsuite/gdb.perf/single-step.c

@@ -0,0 +1,35 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright (C) 2013 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/>.  */
+
+volatile int flag = 1;
+
+int
+main (void)
+{
+  int i = 0;
+
+  while (flag)
+    {
+      double d;
+      float f;
+
+      i++;
+      d = i * 3.14;
+      f = d / 0.618;
+    }
+  return 0;
+}

gdb/testsuite/gdb.perf/single-step.exp

@@ -0,0 +1,56 @@
+# Copyright (C) 2013 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/>.
+
+# This test case is to test the speed of GDB when it is doing singe step.
+# There is one parameter in this test:
+#  - SINGLE_STEP_COUNT is the number of single step GDB performs.
+
+load_lib perftest.exp
+
+if [skip_perf_tests] {
+    return 0
+}
+
+standard_testfile .c
+set executable $testfile
+set expfile $testfile.exp
+
+# make check-perf RUNTESTFLAGS='single-step.exp SINGLE_STEP_COUNT=300'
+if ![info exists SINGLE_STEP_COUNT] {
+    set SINGLE_STEP_COUNT 10000
+}
+
+PerfTest::assemble {
+    global srcdir subdir srcfile binfile
+
+    if { [gdb_compile "$srcdir/$subdir/$srcfile" ${binfile} executable {debug}] != "" } {
+	return -1
+    }
+    return 0
+} {
+    global binfile
+    clean_restart $binfile
+
+    if ![runto_main] {
+	fail "Can't run to main"
+	return -1
+    }
+} {
+    global SINGLE_STEP_COUNT
+
+    gdb_test_no_output "python SingleStep\(${SINGLE_STEP_COUNT}\).run()"
+    # Terminate the loop.
+    gdb_test "set variable flag = 0"
+}

gdb/testsuite/gdb.perf/single-step.py

@@ -0,0 +1,34 @@
+# Copyright (C) 2013 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/>.
+
+from perftest import perftest
+
+class SingleStep (perftest.TestCaseWithBasicMeasurements):
+    def __init__(self, step):
+        super (SingleStep, self).__init__ ("single-step")
+        self.step = step
+
+    def warm_up(self):
+        for _ in range(0, self.step):
+            gdb.execute("stepi", False, True)
+
+    def _run(self, r):
+        for _ in range(0, r):
+            gdb.execute("stepi", False, True)
+
+    def execute_test(self):
+        for i in range(1, 5):
+            func = lambda: self._run(i * self.step)
+            self.measure.measure(func, i * self.step)