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diff --git a/libdexfile/dex/method_reference.h b/libdexfile/dex/method_reference.h
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+/*
+ * Copyright (C) 2013 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef ART_LIBDEXFILE_DEX_METHOD_REFERENCE_H_
+#define ART_LIBDEXFILE_DEX_METHOD_REFERENCE_H_
+
+#include <stdint.h>
+#include <string>
+#include "dex/dex_file.h"
+#include "dex/dex_file_reference.h"
+
+namespace art {
+
+// A method is uniquely located by its DexFile and the method_ids_ table index into that DexFile
+class MethodReference : public DexFileReference {
+ public:
+  MethodReference(const DexFile* file, uint32_t index) : DexFileReference(file, index) {}
+  std::string PrettyMethod(bool with_signature = true) const {
+    return dex_file->PrettyMethod(index, with_signature);
+  }
+  const DexFile::MethodId& GetMethodId() const {
+    return dex_file->GetMethodId(index);
+  }
+};
+
+// Compare the actual referenced method signatures. Used for method reference deduplication.
+struct MethodReferenceValueComparator {
+  bool operator()(MethodReference mr1, MethodReference mr2) const {
+    if (mr1.dex_file == mr2.dex_file) {
+      DCHECK_EQ(mr1.index < mr2.index, SlowCompare(mr1, mr2));
+      return mr1.index < mr2.index;
+    } else {
+      return SlowCompare(mr1, mr2);
+    }
+  }
+
+  bool SlowCompare(MethodReference mr1, MethodReference mr2) const {
+    // The order is the same as for method ids in a single dex file.
+    // Compare the class descriptors first.
+    const DexFile::MethodId& mid1 = mr1.GetMethodId();
+    const DexFile::MethodId& mid2 = mr2.GetMethodId();
+    int descriptor_diff = strcmp(mr1.dex_file->StringByTypeIdx(mid1.class_idx_),
+                                 mr2.dex_file->StringByTypeIdx(mid2.class_idx_));
+    if (descriptor_diff != 0) {
+      return descriptor_diff < 0;
+    }
+    // Compare names second.
+    int name_diff = strcmp(mr1.dex_file->GetMethodName(mid1), mr2.dex_file->GetMethodName(mid2));
+    if (name_diff != 0) {
+      return name_diff < 0;
+    }
+    // And then compare proto ids, starting with return type comparison.
+    const DexFile::ProtoId& prid1 = mr1.dex_file->GetProtoId(mid1.proto_idx_);
+    const DexFile::ProtoId& prid2 = mr2.dex_file->GetProtoId(mid2.proto_idx_);
+    int return_type_diff = strcmp(mr1.dex_file->StringByTypeIdx(prid1.return_type_idx_),
+                                  mr2.dex_file->StringByTypeIdx(prid2.return_type_idx_));
+    if (return_type_diff != 0) {
+      return return_type_diff < 0;
+    }
+    // And finishing with lexicographical parameter comparison.
+    const DexFile::TypeList* params1 = mr1.dex_file->GetProtoParameters(prid1);
+    size_t param1_size = (params1 != nullptr) ? params1->Size() : 0u;
+    const DexFile::TypeList* params2 = mr2.dex_file->GetProtoParameters(prid2);
+    size_t param2_size = (params2 != nullptr) ? params2->Size() : 0u;
+    for (size_t i = 0, num = std::min(param1_size, param2_size); i != num; ++i) {
+      int param_diff = strcmp(mr1.dex_file->StringByTypeIdx(params1->GetTypeItem(i).type_idx_),
+                              mr2.dex_file->StringByTypeIdx(params2->GetTypeItem(i).type_idx_));
+      if (param_diff != 0) {
+        return param_diff < 0;
+      }
+    }
+    return param1_size < param2_size;
+  }
+};
+
+}  // namespace art
+
+#endif  // ART_LIBDEXFILE_DEX_METHOD_REFERENCE_H_