Added special logic to faciliate profiling the test suite run with the cProfile.py

module.

On my MBP running SnowLeopard:

$ DOTEST_PROFILE=YES DOTEST_SCRIPT_DIR=/Volumes/data/lldb/svn/trunk/test /System/Library/Frameworks/Python.framework/Versions/Current/lib/python2.6/cProfile.py -o my.profile ./dotest.py -v -w 2> ~/Developer/Log/lldbtest.log

After that, I used the pstats.py module to browse the statistics recorded in the my.profile file. 

llvm-svn: 123807

lldb/test/README-TestSuite

@@ -90,3 +90,12 @@ o dotest.pl
   suite become more reliable, we don't expect to be using 'dotest.pl' anymore.
 
   Note: dotest.pl has been moved to the attic directory.
+
+o Profiling dotest.py runs
+
+  I used the following command line thingy to do the profiling on a SnowLeopard
+  machine:
+
+$ DOTEST_PROFILE=YES DOTEST_SCRIPT_DIR=/Volumes/data/lldb/svn/trunk/test /System/Library/Frameworks/Python.framework/Versions/Current/lib/python2.6/cProfile.py -o my.profile ./dotest.py -v -w 2> ~/Developer/Log/lldbtest.log
+
+  After that, I used the pstats.py module to browse the statistics.

lldb/test/dotest.py

@@ -439,6 +439,9 @@ def setupSysPath():
     global testdirs
 
     # Get the directory containing the current script.
+    if "DOTEST_PROFILE" in os.environ and "DOTEST_SCRIPT_DIR" in os.environ:
+        scriptPath = os.environ["DOTEST_SCRIPT_DIR"]
+    else:
         scriptPath = sys.path[0]
     if not scriptPath.endswith('test'):
         print "This script expects to reside in lldb's test directory."