Tag smi-constants as smi.

src/hydrogen-instructions.cc

Index: src/hydrogen-instructions.cc
diff --git a/src/hydrogen-instructions.cc b/src/hydrogen-instructions.cc
index e7e63d1bdc52f64a390a3381702d8989092d1abc..bd33f1a2b7ee38eb0998d783445066d902abe59c 100644
--- a/src/hydrogen-instructions.cc
+++ b/src/hydrogen-instructions.cc
@@ -2165,7 +2165,9 @@ HConstant::HConstant(double double_value,
 
 void HConstant::Initialize(Representation r) {
   if (r.IsNone()) {
-    if (has_int32_value_) {
+    if (has_smi_value_) {
+      r = Representation::Smi();
+    } else if (has_int32_value_) {
       r = Representation::Integer32();
     } else if (has_double_value_) {
       r = Representation::Double();