simpleperf: support showing symbols for interpreted java code.

To convert from a dex_pc (returned by libunwindstack) to a symbol name,
we need below things:
1. The mapping info of the vdex file containing the dex_pc.
2. The offsets of dex files in the vdex file.

So make below changes:
1. Record none executable maps when profiling java code.
2. Refactor dso code to add a new type for dex file, using DexFileDso
   to store dex file offsets in a vdex file, and load symbols from that
   vdex file.
3. Add read_dex_file.cpp to read java symbols using libdexfile.
4. Change the format of file section in record_file_format.h, to store
   dex file offsets in vdex files.

Bug: http://b/73126888
Bug: http://b/77236599
Test: Run simpleperf to profile several apps manually, can see
Test: callstacks of both java code and native code.
Test: Run simpleperf_unit_test.

Change-Id: I08005a03beb3df1a70db034bc463f555934856ba

1 files changed, 35 insertions, 0 deletions

diff --git a/simpleperf/read_dex_file.h b/simpleperf/read_dex_file.h
new file mode 100644
index 00000000..cd01f586
--- /dev/null
+++ b/simpleperf/read_dex_file.h
@@ -0,0 +1,35 @@
+/*
+ * Copyright (C) 2018 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 SIMPLE_PERF_READ_DEX_FILE_H_
+#define SIMPLE_PERF_READ_DEX_FILE_H_
+
+#include <inttypes.h>
+
+#include <string>
+#include <vector>
+
+struct DexFileSymbol {
+  uint64_t offset;
+  uint64_t len;
+  std::string name;
+};
+
+bool ReadSymbolsFromDexFile(const std::string& file_path,
+                            const std::vector<uint64_t>& dex_file_offsets,
+                            std::vector<DexFileSymbol>* symbols);
+
+#endif  // SIMPLE_PERF_READ_DEX_FILE_H_