handle variables that assign a value including themselves in aggressiveVariableElimination

Author: kripken

tests/test_core.py

@@ -4652,12 +4652,15 @@ def test_lua(self):
     if Settings.QUANTUM_SIZE == 1: return self.skip('TODO: make this work')
     if os.environ.get('EMCC_FAST_COMPILER') == '1': return self.skip('todo in fastcomp')
 
-    self.do_run('',
-                'hello lua world!\n17\n1\n2\n3\n4\n7',
-                args=['-e', '''print("hello lua world!");print(17);for x = 1,4 do print(x) end;print(10-3)'''],
-                libraries=self.get_library('lua', [os.path.join('src', 'lua'), os.path.join('src', 'liblua.a')], make=['make', 'generic'], configure=None),
-                includes=[path_from_root('tests', 'lua')],
-                output_nicerizer=lambda string, err: (string + err).replace('\n\n', '\n').replace('\n\n', '\n'))
+    for aggro in ([0, 1] if '-O2' in self.emcc_args else [0]):
+      print aggro
+      Settings.AGGRESSIVE_VARIABLE_ELIMINATION = aggro
+      self.do_run('',
+                  'hello lua world!\n17\n1\n2\n3\n4\n7',
+                  args=['-e', '''print("hello lua world!");print(17);for x = 1,4 do print(x) end;print(10-3)'''],
+                  libraries=self.get_library('lua', [os.path.join('src', 'lua'), os.path.join('src', 'liblua.a')], make=['make', 'generic'], configure=None),
+                  includes=[path_from_root('tests', 'lua')],
+                  output_nicerizer=lambda string, err: (string + err).replace('\n\n', '\n').replace('\n\n', '\n'))
 
   def get_freetype(self):
     Settings.DEAD_FUNCTIONS += ['_inflateEnd', '_inflate', '_inflateReset', '_inflateInit2_']

tools/js-optimizer.js

@@ -3030,24 +3030,29 @@ function aggressiveVariableEliminationInternal(func, asmData) {
 
   allTrivials = {};
 
-  var values = {};
+  var values = {}, recursives = {};
 
   function evaluate(name) {
     var node = values[name];
     if (node) return node;
-    values[node] = null; // prevent infinite recursion
+    values[name] = null; // prevent infinite recursion
     var def = defs[name];
     if (def) {
       node = def[3];
       if (node[0] == 'name') {
         var name2 = node[1];
+        assert(name2 !== name);
         if (name2 in trivials) {
           node = evaluate(name2);
         }
       } else {
         traverse(node, function(node, type) {
           if (type == 'name') {
             var name2 = node[1];
+            if (name2 === name) {
+              recursives[name] = 1;
+              return false;
+            }
             if (name2 in trivials) {
               return evaluate(name2);
             }
@@ -3062,6 +3067,9 @@ function aggressiveVariableEliminationInternal(func, asmData) {
   for (var name in trivials) {
     evaluate(name);
   }
+  for (var name in recursives) {
+    delete trivials[name];
+  }
 
   for (var name in trivials) {
     var def = defs[name];