Fix reintroduction of global variables that have been deleted.

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 8fad814fad337863420e50b3a3c4116167e12bd1..1ccad1774f11ec83884ea33dfecd79ebc6a01309 100644
--- a/src/arm/lithium-codegen-arm.cc
+++ b/src/arm/lithium-codegen-arm.cc
@@ -2195,8 +2195,26 @@ void LCodeGen::DoLoadGlobal(LLoadGlobal* instr) {
 
 void LCodeGen::DoStoreGlobal(LStoreGlobal* instr) {
   Register value = ToRegister(instr->InputAt(0));
-  __ mov(ip, Operand(Handle<Object>(instr->hydrogen()->cell())));
-  __ str(value, FieldMemOperand(ip, JSGlobalPropertyCell::kValueOffset));
+  Register scratch = scratch0();
+
+  // Load the cell.
+  __ mov(scratch, Operand(Handle<Object>(instr->hydrogen()->cell())));
+
+  // If the cell we are storing to contains the hole it could have
+  // been deleted from the property dictionary. In that case, we need
+  // to update the property details in the property dictionary to mark
+  // it as no longer deleted.
+  if (instr->hydrogen()->check_hole_value()) {
+    Register scratch2 = ToRegister(instr->TempAt(0));
+    __ ldr(scratch2,
+           FieldMemOperand(scratch, JSGlobalPropertyCell::kValueOffset));
+    __ LoadRoot(ip, Heap::kTheHoleValueRootIndex);
+    __ cmp(scratch2, ip);
+    DeoptimizeIf(eq, instr->environment());
+  }
+
+  // Store the value.
+  __ str(value, FieldMemOperand(scratch, JSGlobalPropertyCell::kValueOffset));
 }