make EMTERPRETIFY_ADVISE helpful regarding the yield list

src/settings.js

@@ -632,6 +632,8 @@ var EMTERPRETIFY_ADVISE = 0; // Performs a static analysis to suggest which func
                              // appears they can be on the stack when a sync function is called in the EMTERPRETIFY_ASYNC option.
                              // After showing the suggested list, compilation will halt. You can apply the provided list as an
                              // emcc argument when compiling later.
+                             // This will also advise on the YIELDLIST, if it contains at least one value (it then reports
+                             // all things reachable from that function, as they may need to be in the YIELDLIST as well).
                              // Note that this depends on things like inlining. If you run this with different inlining than
                              // when you use the list, it might not work.
 

tests/test_other.py

@@ -4606,6 +4606,13 @@ function _main() {
 
     out, err = Popen([PYTHON, EMCC, path_from_root('tests', 'emterpreter_advise_funcptr.cpp'), '-s', 'EMTERPRETIFY=1', '-s', 'EMTERPRETIFY_ASYNC=1', '-s', 'EMTERPRETIFY_ADVISE=1'], stdout=PIPE).communicate()
     self.assertContained('-s EMTERPRETIFY_WHITELIST=\'["__Z4posti", "__Z5post2i", "__Z6middlev", "__Z7sleeperv", "__Z8recurserv", "_main"]\'', out)
+    self.assertNotContained('EMTERPRETIFY_YIELDLIST', out);
+
+    out, err = Popen([PYTHON, EMCC, path_from_root('tests', 'emterpreter_advise_funcptr.cpp'), '-s', 'EMTERPRETIFY=1', '-s', 'EMTERPRETIFY_ASYNC=1', '-s', 'EMTERPRETIFY_ADVISE=1', '-s', 'EMTERPRETIFY_YIELDLIST=["__Z6middlev"]'], stdout=PIPE).communicate()
+    self.assertContained('-s EMTERPRETIFY_YIELDLIST=\'["__Z6middlev", "__Z7siblingii", "__Z7sleeperv", "__Z8recurserv", "_printf"]\'', out)
+
+    out, err = Popen([PYTHON, EMCC, path_from_root('tests', 'emterpreter_advise_funcptr.cpp'), '-s', 'EMTERPRETIFY=1', '-s', 'EMTERPRETIFY_ASYNC=1', '-s', 'EMTERPRETIFY_ADVISE=1', '-s', 'EMTERPRETIFY_YIELDLIST=["__Z3pref"]'], stdout=PIPE).communicate()
+    self.assertContained('-s EMTERPRETIFY_YIELDLIST=\'["__Z3pref", "__Z7siblingii", "_printf"]\'', out)
 
   def test_link_with_a_static(self):
     for args in [[], ['-O2']]:

tools/emterpretify.py

@@ -706,6 +706,8 @@ if __name__ == '__main__':
   outfile = sys.argv[2]
   force_memfile = sys.argv[3] if len(sys.argv) >= 4 else None
 
+  original_yieldlist = YIELDLIST
+
   extra_blacklist = []
   if len(sys.argv) >= 5:
     temp = sys.argv[4]
@@ -775,6 +777,23 @@ if __name__ == '__main__':
     print "Suggested list of functions to run in the emterpreter:"
     print "  -s EMTERPRETIFY_WHITELIST='" + str(sorted(list(advised))).replace("'", '"') + "'"
     print "(%d%% out of %d functions)" % (int((100.0*len(advised))/len(can_call)), len(can_call))
+    if len(YIELDLIST) > len(original_yieldlist):
+      # advise on the yield list as well. Anything a yield function can reach, likely needs to also be a yield function
+      YIELD_IGNORE = set(['abort'])
+      to_check = list(YIELDLIST)
+      advised = set([str(f) for f in YIELDLIST])
+      while len(to_check) > 0:
+        curr = to_check.pop()
+        if curr not in can_call: continue
+        for next in can_call[curr]:
+          if next not in advised:
+            advised.add(str(next))
+            to_check.append(next)
+      advised = [next for next in advised if not is_dyn_call(next) and not is_function_table(next) and not next in original_yieldlist and next not in SYNC_FUNCS and next not in YIELD_IGNORE and next[0] == '_']
+      print
+      print "Suggested list of yield functions for the emterpreter:"
+      print "  -s EMTERPRETIFY_YIELDLIST='" + str(sorted(list(advised))).replace("'", '"') + "'"
+      print "(%d%% out of %d functions)" % (int((100.0*len(advised))/len(can_call)), len(can_call))
     sys.exit(0)
 
   BLACKLIST = set(list(BLACKLIST) + extra_blacklist)