diff --git a/compiler/dex/global_value_numbering_test.cc b/compiler/dex/global_value_numbering_test.cc
index f71b7ae..cfa6388 100644
--- a/compiler/dex/global_value_numbering_test.cc
+++ b/compiler/dex/global_value_numbering_test.cc
@@ -229,7 +229,7 @@
 
   void DoPrepareMIRs(const MIRDef* defs, size_t count) {
     mir_count_ = count;
-    mirs_ = reinterpret_cast<MIR*>(cu_.arena.Alloc(sizeof(MIR) * count, kArenaAllocMIR));
+    mirs_ = cu_.arena.AllocArray<MIR>(count, kArenaAllocMIR);
     ssa_reps_.resize(count);
     for (size_t i = 0u; i != count; ++i) {
       const MIRDef* def = &defs[i];
@@ -251,8 +251,8 @@
         ASSERT_EQ(cu_.mir_graph->sfield_lowering_infos_[def->field_info].MemAccessType(),
                   SGetOrSPutMemAccessType(def->opcode));
       } else if (def->opcode == static_cast<Instruction::Code>(kMirOpPhi)) {
-        mir->meta.phi_incoming = static_cast<BasicBlockId*>(
-            allocator_->Alloc(def->num_uses * sizeof(BasicBlockId), kArenaAllocDFInfo));
+        mir->meta.phi_incoming =
+            allocator_->AllocArray<BasicBlockId>(def->num_uses, kArenaAllocDFInfo);
         ASSERT_EQ(def->num_uses, bb->predecessors.size());
         std::copy(bb->predecessors.begin(), bb->predecessors.end(), mir->meta.phi_incoming);
       }