doubling the number of tests, but not taking twice as long

[Larry Martell]

I had some code that did this:

meas_regex = '_M\d+_'
meas_re = re.compile(meas_regex)

if meas_re.search(filename):
    stuff1()
else:
    stuff2()

I then had to change it to this:

if meas_re.search(filename):
    if 'MeasDisplay' in filename:
        stuff1a()
    else:
        stuff1()
else:
    if 'PatternFov' in filename:
        stuff2a()
   else:
        stuff2()

This code needs to process many tens of 1000's of files, and it runs
often, so it needs to run very fast. Needless to say, my change has
made it take 2x as long. Can anyone see a way to improve that?