X87: Don't MISS if you read the hole from certain FastHoley arrays.

src/x87/lithium-x87.cc

Index: src/x87/lithium-x87.cc
diff --git a/src/x87/lithium-x87.cc b/src/x87/lithium-x87.cc
index 0bf162c2533222c0ee0b47d507fe00f423438862..2c4de87d3fb74f1e6f3b77890dc92b7c0c4e8990 100644
--- a/src/x87/lithium-x87.cc
+++ b/src/x87/lithium-x87.cc
@@ -2227,14 +2227,21 @@ LInstruction* LChunkBuilder::DoLoadKeyed(HLoadKeyed* instr) {
     result = DefineAsRegister(new(zone()) LLoadKeyed(backing_store, key));
   }
 
-  if ((instr->is_external() || instr->is_fixed_typed_array()) ?
-      // see LCodeGen::DoLoadKeyedExternalArray
-      ((instr->elements_kind() == EXTERNAL_UINT32_ELEMENTS ||
-        instr->elements_kind() == UINT32_ELEMENTS) &&
-       !instr->CheckFlag(HInstruction::kUint32)) :
-      // see LCodeGen::DoLoadKeyedFixedDoubleArray and
-      // LCodeGen::DoLoadKeyedFixedArray
-      instr->RequiresHoleCheck()) {
+  bool needs_environment;
+  if (instr->is_external() || instr->is_fixed_typed_array()) {
+    // see LCodeGen::DoLoadKeyedExternalArray
+    needs_environment = (elements_kind == EXTERNAL_UINT32_ELEMENTS ||
+                         elements_kind == UINT32_ELEMENTS) &&
+                        !instr->CheckFlag(HInstruction::kUint32);
+  } else {
+    // see LCodeGen::DoLoadKeyedFixedDoubleArray and
+    // LCodeGen::DoLoadKeyedFixedArray
+    needs_environment =
+        instr->RequiresHoleCheck() ||
+        (instr->hole_mode() == CONVERT_HOLE_TO_UNDEFINED && info()->IsStub());
+  }
+
+  if (needs_environment) {
     result = AssignEnvironment(result);
   }
   return result;