Check in a customized benchmark which compares the Xcode 4.1 vs. Xcode 4.2's gdb disassembly speed

on lldb's Driver::MainLoop function which is ~1190 lines of x86 assembly code.  This file is not
exercised during the normal test suite run, i.e., no +b option specified.  So it should be ok.

The following is the benchmark result on my MBP running OSX Lion:

[17:38:46] johnny:/Volumes/data/lldb/svn/trunk/test $ ./dotest.py -v +b -p TestFlintVsSlate
/Volumes/data/lldb/svn/trunk/build/Debug
LLDB-71
Path: /Volumes/data/lldb/svn/trunk
URL: https://johnny@llvm.org/svn/llvm-project/lldb/trunk
Repository Root: https://johnny@llvm.org/svn/llvm-project
Repository UUID: 91177308-0d34-0410-b5e6-96231b3b80d8
Revision: 137008
Node Kind: directory
Schedule: normal
Last Changed Author: gclayton
Last Changed Rev: 137008
Last Changed Date: 2011-08-05 17:50:36 -0700 (Fri, 05 Aug 2011)



Session logs for test failures/errors/unexpected successes will go into directory '2011-08-08-17_38_52'
Command invoked: python ./dotest.py -v +b -p TestFlintVsSlate
----------------------------------------------------------------------
Collected 2 tests

1: test_run_41_then_42 (TestFlintVsSlateGDBDisassembly.FlintVsSlateGDBDisassembly)
   Test disassembly on a large function with 4.1 vs. 4.2's gdb. ... 
4.1 gdb benchmark: Avg: 0.205623 (Laps: 5, Total Elapsed Time: 1.028113)
4.2 gdb benchmark: Avg: 0.201970 (Laps: 5, Total Elapsed Time: 1.009849)
gdb_42_avg/gdb_41_avg: 0.982236
ok
2: test_run_42_then_41 (TestFlintVsSlateGDBDisassembly.FlintVsSlateGDBDisassembly)
   Test disassembly on a large function with 4.1 vs. 4.2's gdb. ... 
4.2 gdb benchmark: Avg: 0.202602 (Laps: 5, Total Elapsed Time: 1.013012)
4.1 gdb benchmark: Avg: 0.204418 (Laps: 5, Total Elapsed Time: 1.022089)
gdb_42_avg/gdb_41_avg: 0.991119
ok

----------------------------------------------------------------------
Ran 2 tests in 15.688s

OK

llvm-svn: 137092

1 files changed, 92 insertions, 0 deletions

diff --git a/lldb/test/benchmarks/disassembly/TestFlintVsSlateGDBDisassembly.py b/lldb/test/benchmarks/disassembly/TestFlintVsSlateGDBDisassembly.py
new file mode 100644
index 00000000000..48c29168f46
--- /dev/null
+++ b/lldb/test/benchmarks/disassembly/TestFlintVsSlateGDBDisassembly.py
@@ -0,0 +1,92 @@
+"""Disassemble lldb's Driver::MainLoop() functions comparing Xcode 4.1 vs. 4.2's gdb."""
+
+import os, sys
+import unittest2
+import lldb
+import pexpect
+from lldbbench import *
+
+class FlintVsSlateGDBDisassembly(BenchBase):
+
+    mydir = os.path.join("benchmarks", "example")
+
+    def setUp(self):
+        BenchBase.setUp(self)
+        self.gdb_41_exe = '/Flint/usr/bin/gdb'
+        self.gdb_42_exe = '/Developer/usr/bin/gdb'
+        self.exe = self.lldbExec
+        self.function = 'Driver::MainLoop()'
+        self.gdb_41_avg = None
+        self.gdb_42_avg = None
+
+    @benchmarks_test
+    def test_run_41_then_42(self):
+        """Test disassembly on a large function with 4.1 vs. 4.2's gdb."""
+        print
+        self.run_gdb_disassembly(self.gdb_41_exe, self.exe, self.function, 5)
+        print "4.1 gdb benchmark:", self.stopwatch
+        self.gdb_41_avg = self.stopwatch.avg()
+        self.run_gdb_disassembly(self.gdb_42_exe, self.exe, self.function, 5)
+        print "4.2 gdb benchmark:", self.stopwatch
+        self.gdb_42_avg = self.stopwatch.avg()
+        print "gdb_42_avg/gdb_41_avg: %f" % (self.gdb_42_avg/self.gdb_41_avg)
+
+    @benchmarks_test
+    def test_run_42_then_41(self):
+        """Test disassembly on a large function with 4.1 vs. 4.2's gdb."""
+        print
+        self.run_gdb_disassembly(self.gdb_42_exe, self.exe, self.function, 5)
+        print "4.2 gdb benchmark:", self.stopwatch
+        self.gdb_42_avg = self.stopwatch.avg()
+        self.run_gdb_disassembly(self.gdb_41_exe, self.exe, self.function, 5)
+        print "4.1 gdb benchmark:", self.stopwatch
+        self.gdb_41_avg = self.stopwatch.avg()
+        print "gdb_42_avg/gdb_41_avg: %f" % (self.gdb_42_avg/self.gdb_41_avg)
+
+    def run_gdb_disassembly(self, gdb_exe_path, exe, function, count):
+        # Set self.child_prompt, which is "(gdb) ".
+        self.child_prompt = '(gdb) '
+        prompt = self.child_prompt
+
+        # So that the child gets torn down after the test.
+        self.child = pexpect.spawn('%s %s' % (gdb_exe_path, exe))
+        child = self.child
+
+        # Turn on logging for what the child sends back.
+        if self.TraceOn():
+            child.logfile_read = sys.stdout
+
+        child.expect_exact(prompt)
+        child.sendline('break %s' % function)
+        child.expect_exact(prompt)
+        child.sendline('run')
+        child.expect_exact(prompt)
+
+        # Reset the stopwatch now.
+        self.stopwatch.reset()
+        for i in range(count):
+            with self.stopwatch:
+                # Disassemble the function.
+                child.sendline('disassemble')
+                child.expect_exact(prompt)
+            child.sendline('next')
+            child.expect_exact(prompt)
+
+        child.sendline('quit')
+        child.expect_exact('The program is running.  Exit anyway?')
+        child.sendline('y')
+        try:
+            self.child.expect(pexpect.EOF)
+        except:
+            pass
+
+        if self.TraceOn():
+            print "gdb disassembly benchmark:", str(self.stopwatch)
+        self.child = None
+
+
+if __name__ == '__main__':
+    import atexit
+    lldb.SBDebugger.Initialize()
+    atexit.register(lambda: lldb.SBDebugger.Terminate())
+    unittest2.main()