Emit CFI for x86 & x86_64 JNI compiler.

Now for host-side x86 & x86_64 ART, we are able to get complete stacktrace with even mixed C/C++ & Java stack frames.

Testing:
1. art/test/run-test --host --gdb [--64] --no-relocate 005
2. In gdb, run 'b art::Class_classForName' which is implementation of a Java native method, then 'r'
3. In gdb, run 'bt'. You should see stack frames down to main()

Change-Id: I2d17e9aa0f6d42d374b5362a15ea35a2fce96302
diff --git a/compiler/utils/dwarf_cfi.h b/compiler/utils/dwarf_cfi.h
new file mode 100644
index 0000000..e5acc0e
--- /dev/null
+++ b/compiler/utils/dwarf_cfi.h
@@ -0,0 +1,91 @@
+/*
+ * Copyright (C) 2014 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_COMPILER_UTILS_DWARF_CFI_H_
+#define ART_COMPILER_UTILS_DWARF_CFI_H_
+
+#include <vector>
+
+namespace art {
+
+/**
+ * @brief Enter a 'DW_CFA_advance_loc' into an FDE buffer
+ * @param buf FDE buffer.
+ * @param increment Amount by which to increase the current location.
+ */
+void DW_CFA_advance_loc(std::vector<uint8_t>* buf, uint32_t increment);
+
+/**
+ * @brief Enter a 'DW_CFA_offset_extended_sf' into an FDE buffer
+ * @param buf FDE buffer.
+ * @param reg Register number.
+ * @param offset Offset of register address from CFA.
+ */
+void DW_CFA_offset_extended_sf(std::vector<uint8_t>* buf, int reg, int32_t offset);
+
+/**
+ * @brief Enter a 'DW_CFA_offset' into an FDE buffer
+ * @param buf FDE buffer.
+ * @param reg Register number.
+ * @param offset Offset of register address from CFA.
+ */
+void DW_CFA_offset(std::vector<uint8_t>* buf, int reg, uint32_t offset);
+
+/**
+ * @brief Enter a 'DW_CFA_def_cfa_offset' into an FDE buffer
+ * @param buf FDE buffer.
+ * @param offset New offset of CFA.
+ */
+void DW_CFA_def_cfa_offset(std::vector<uint8_t>* buf, int32_t offset);
+
+/**
+ * @brief Enter a 'DW_CFA_remember_state' into an FDE buffer
+ * @param buf FDE buffer.
+ */
+void DW_CFA_remember_state(std::vector<uint8_t>* buf);
+
+/**
+ * @brief Enter a 'DW_CFA_restore_state' into an FDE buffer
+ * @param buf FDE buffer.
+ */
+void DW_CFA_restore_state(std::vector<uint8_t>* buf);
+
+/**
+ * @brief Write FDE header into an FDE buffer
+ * @param buf FDE buffer.
+ */
+void WriteFDEHeader(std::vector<uint8_t>* buf);
+
+/**
+ * @brief Set 'address_range' field of an FDE buffer
+ * @param buf FDE buffer.
+ */
+void WriteFDEAddressRange(std::vector<uint8_t>* buf, uint32_t data);
+
+/**
+ * @brief Set 'length' field of an FDE buffer
+ * @param buf FDE buffer.
+ */
+void WriteCFILength(std::vector<uint8_t>* buf);
+
+/**
+ * @brief Pad an FDE buffer with 0 until its size is a multiple of 4
+ * @param buf FDE buffer.
+ */
+void PadCFI(std::vector<uint8_t>* buf);
+}  // namespace art
+
+#endif  // ART_COMPILER_UTILS_DWARF_CFI_H_