allow adding more functions to emterpreter blacklist

emcc

@@ -1488,10 +1488,11 @@ try:
   if shared.Settings.EMTERPRETIFY:
     logging.debug('emterpretifying')
     assert memory_init_file, 'emterpreter requires a mem init file'
+    import json
     try:
       # move temp js to final position, alongside its mem init file
       shutil.move(final, js_target)
-      execute([shared.PYTHON, shared.path_from_root('tools', 'emterpretify.py'), js_target, final + '.em.js', memfile])
+      execute([shared.PYTHON, shared.path_from_root('tools', 'emterpretify.py'), js_target, final + '.em.js', memfile, json.dumps(shared.Settings.EMTERPRETIFY_BLACKLIST)])
       final = final + '.em.js'
     finally:
       shared.try_delete(js_target)

src/settings.js

@@ -563,6 +563,7 @@ var NO_DYNAMIC_EXECUTION = 0; // When enabled, we do not emit eval() and new Fun
                               // privileged firefox app, etc.)
 
 var EMTERPRETIFY = 0; // Runs tools/emterpretify on the compiler output
+var EMTERPRETIFY_BLACKLIST = []; // Functions to not emterpret, that is, to run normally at full speed
 
 var RUNNING_JS_OPTS = 0; // whether js opts will be run, after the main compiler
 var RUNNING_FASTCOMP = 1; // whether we are running the fastcomp backend

tools/emterpretify.py

@@ -558,6 +558,8 @@ function emterpret%s(pc) {
 infile = sys.argv[1]
 outfile = sys.argv[2]
 force_memfile = sys.argv[3] if len(sys.argv) >= 4 else None
+if len(sys.argv) >= 5:
+  BLACKLIST = set(list(BLACKLIST) + json.loads(sys.argv[4]))
 
 #print 'emterpretifying %s to %s' % (infile, outfile)