1 files changed, 24 insertions, 20 deletions

diff --git a/src/passes/OptimizeInstructions.cpp b/src/passes/OptimizeInstructions.cpp
index ec646d89f..8381a0e1f 100644
--- a/src/passes/OptimizeInstructions.cpp
+++ b/src/passes/OptimizeInstructions.cpp
@@ -214,37 +214,41 @@ struct OptimizeInstructions : public WalkerPass<PostWalker<OptimizeInstructions,
       if (get && get->name == set->name) {
         ExpressionManipulator::nop(curr);
       }
+    } else if (auto* iff = curr->dynCast<If>()) {
+      iff->condition = optimizeBoolean(iff->condition);
     } else if (auto* select = curr->dynCast<Select>()) {
+      select->condition = optimizeBoolean(select->condition);
       auto* condition = select->condition->dynCast<Unary>();
       if (condition && condition->op == EqZInt32) {
-        auto* condition2 = condition->value->dynCast<Unary>();
-        if (condition2 && condition2->op == EqZInt32) {
-          // double eqz
-          select->condition = condition2->value;
-        } else {
-          // flip select, eqz input and flippable
-          EffectAnalyzer ifTrue(select->ifTrue);
-          EffectAnalyzer ifFalse(select->ifFalse);
-          if (!ifTrue.invalidates(ifFalse)) {
-            select->condition = condition->value;
-            std::swap(select->ifTrue, select->ifFalse);
-          }
+        // flip select to remove eqz, if we can reorder
+        EffectAnalyzer ifTrue(select->ifTrue);
+        EffectAnalyzer ifFalse(select->ifFalse);
+        if (!ifTrue.invalidates(ifFalse)) {
+          select->condition = condition->value;
+          std::swap(select->ifTrue, select->ifFalse);
         }
       }
     } else if (auto* br = curr->dynCast<Break>()) {
       if (br->condition) {
-        auto* condition = br->condition->dynCast<Unary>();
-        if (condition && condition->op == EqZInt32) {
-          auto* condition2 = condition->value->dynCast<Unary>();
-          if (condition2 && condition2->op == EqZInt32) {
-            // double eqz
-            br->condition = condition2->value;
-          }
-        }
+        br->condition = optimizeBoolean(br->condition);
       }
     }
     return nullptr;
   }
+
+private:
+
+  Expression* optimizeBoolean(Expression* boolean) {
+    auto* condition = boolean->dynCast<Unary>();
+    if (condition && condition->op == EqZInt32) {
+      auto* condition2 = condition->value->dynCast<Unary>();
+      if (condition2 && condition2->op == EqZInt32) {
+        // double eqz
+        return condition2->value;
+      }
+    }
+    return boolean;
+  }
 };
 
 Pass *createOptimizeInstructionsPass() {