do not try to eliminate phi variables, which are unsafe to be removed and the llvm optimizer will remove anyhow if unused

1 files changed, 1 insertions, 1 deletions

diff --git a/tools/js-optimizer.js b/tools/js-optimizer.js
index 29aecdcf..62161738 100644
--- a/tools/js-optimizer.js
+++ b/tools/js-optimizer.js
@@ -1464,7 +1464,7 @@ function eliminate(ast, memSafe) {
     for (var name in locals) {
       if (definitions[name] == 1 && uses[name] == 1) {
         potentials[name] = 1;
-      } else if (uses[name] == 0) {
+      } else if (uses[name] == 0 && (!definitions[name] || definitions[name] <= 1)) { // no uses, no def or 1 def (cannot operate on phis, and the llvm optimizer will remove unneeded phis anyhow)
         var hasSideEffects = false;
         if (values[name]) {
           traverse(values[name], function(node, type) {