Handle holes in smi-untag from LoadKeyed requiring hole handling.

src/arm/lithium-codegen-arm.cc

Index: src/arm/lithium-codegen-arm.cc
diff --git a/src/arm/lithium-codegen-arm.cc b/src/arm/lithium-codegen-arm.cc
index 09a0e9c066fcc671526ee5dd344a2cd6016c2691..e12fcb761acf29707f924f0eac2dd4ac26243de3 100644
--- a/src/arm/lithium-codegen-arm.cc
+++ b/src/arm/lithium-codegen-arm.cc
@@ -4905,6 +4905,21 @@ void LCodeGen::DoSmiUntag(LSmiUntag* instr) {
     // If the input is a HeapObject, SmiUntag will set the carry flag.
     __ SmiUntag(result, input, SetCC);
     DeoptimizeIf(cs, instr->environment());
+  } else if (instr->hydrogen()->value()->IsLoadKeyed()) {
+    HLoadKeyed* load = HLoadKeyed::cast(instr->hydrogen()->value());
+    if (load->UsesMustHandleHole()) {
+      __ SmiUntag(result, input, SetCC);
+      if (load->hole_mode() == ALLOW_RETURN_HOLE) {
+        Label done;
+        __ b(cc, &done);
+        __ mov(result, Operand(Smi::FromInt(0)));
+        __ bind(&done);
+      } else {
+        DeoptimizeIf(cs, instr->environment());
+      }
+    } else {
+      __ SmiUntag(result, input);
+    }
   } else {
     __ SmiUntag(result, input);
   }