Add ability to read jit gdb data.

Changes:
- New JitDebug class to handle all of the jit gdb interface.
- Add unit tests for all, along with new offline test using debug data.
- Add new Memory type called MemoryOfflineParts that has multiple
  MemoryOffline objects to support the offline test.
- Update the tools to use the JitDebug object.
- Modify libbacktrace to use the JitDebug, but only looking in libart.so
  and libartd.so.
- Change the Format32Bits to Is32Bit since it's more accurate and I use
  it in a different context where original name didn't make sense.
- Add a new function to find global variables in an elf file
  (GetGlobalVariable).
- Add a new function to determine if a pc is valid for this elf (IsValidPc).

Bug: 68396769

Test: Ran new unit tests. Added new offline test that uses jit debug data.
Test: Ran art test that generates jit data and verified a crash unwinds
Test: through the jit data.
Change-Id: I6e7ee2f5bab2242028a06feece156dff21c0a974

1 files changed, 3 insertions, 0 deletions

diff --git a/libunwindstack/Symbols.h b/libunwindstack/Symbols.h
index 689144b..7d239c1 100644
--- a/libunwindstack/Symbols.h
+++ b/libunwindstack/Symbols.h
@@ -47,6 +47,9 @@ class Symbols {
   bool GetName(uint64_t addr, uint64_t load_bias, Memory* elf_memory, std::string* name,
                uint64_t* func_offset);
 
+  template <typename SymType>
+  bool GetGlobal(Memory* elf_memory, const std::string& name, uint64_t* memory_address);
+
   void ClearCache() {
     symbols_.clear();
     cur_offset_ = offset_;