Performance drop since 2.0.2 release

We recently tried to move to 2.0.15 and noticed a 10-20% increase in run time of our application, this also showed up in tests that are allocating memory. We traced this back to starting at 2.0.2.
The attached programme which i compile with
call em++ -s DISABLE_EXCEPTION_CATCHING=0 -s INITIAL_MEMORY=1024MB -s ASSERTIONS=0 -s DEMANGLE_SUPPORT=0 -O3 -DNDEBUG=1 test.cpp -o test.js
and the run with
node test.js
shows time for 2.0.1 to do the malloc's
Time difference = 5447635 msecs
and for 2.0.2
Time difference = 8133452 msecs

I have looked through the commits in emscripten between the 2 releases and don't understand which of them is causing this.
It doesn't matter if we turn exception handling on or off.