Revert "Check for data races when reading JIT/DEX entries."

This reverts commit 85b5fecec920208ec43b42488f08d4c2e5aaeda2.

Reason for revert: Breaks ART tests, reverting to investigate.

Change-Id: I1bb905407e87cbd4f832646651133a9caf6fcfc8
diff --git a/libbacktrace/UnwindStack.cpp b/libbacktrace/UnwindStack.cpp
index ff19833..f5f9b2a 100644
--- a/libbacktrace/UnwindStack.cpp
+++ b/libbacktrace/UnwindStack.cpp
@@ -32,6 +32,9 @@
 #include <unwindstack/Regs.h>
 #include <unwindstack/RegsGetLocal.h>
 
+#if !defined(NO_LIBDEXFILE_SUPPORT)
+#include <unwindstack/DexFiles.h>
+#endif
 #include <unwindstack/Unwinder.h>
 
 #include "BacktraceLog.h"
@@ -47,6 +50,14 @@
                                  regs, stack_map->process_memory());
   unwinder.SetResolveNames(stack_map->ResolveNames());
   stack_map->SetArch(regs->Arch());
+  if (stack_map->GetJitDebug() != nullptr) {
+    unwinder.SetJitDebug(stack_map->GetJitDebug(), regs->Arch());
+  }
+#if !defined(NO_LIBDEXFILE_SUPPORT)
+  if (stack_map->GetDexFiles() != nullptr) {
+    unwinder.SetDexFiles(stack_map->GetDexFiles(), regs->Arch());
+  }
+#endif
   unwinder.Unwind(skip_names, &stack_map->GetSuffixesToIgnore());
   if (error != nullptr) {
     switch (unwinder.LastErrorCode()) {
diff --git a/libbacktrace/UnwindStackMap.cpp b/libbacktrace/UnwindStackMap.cpp
index 726fdfa..4518891 100644
--- a/libbacktrace/UnwindStackMap.cpp
+++ b/libbacktrace/UnwindStackMap.cpp
@@ -43,6 +43,13 @@
   // Create the process memory object.
   process_memory_ = unwindstack::Memory::CreateProcessMemory(pid_);
 
+  // Create a JitDebug object for getting jit unwind information.
+  std::vector<std::string> search_libs_{"libart.so", "libartd.so"};
+  jit_debug_.reset(new unwindstack::JitDebug(process_memory_, search_libs_));
+#if !defined(NO_LIBDEXFILE_SUPPORT)
+  dex_files_.reset(new unwindstack::DexFiles(process_memory_, search_libs_));
+#endif
+
   if (!stack_maps_->Parse()) {
     return false;
   }
diff --git a/libbacktrace/UnwindStackMap.h b/libbacktrace/UnwindStackMap.h
index 9bb9709..e19b605 100644
--- a/libbacktrace/UnwindStackMap.h
+++ b/libbacktrace/UnwindStackMap.h
@@ -27,6 +27,9 @@
 
 #include <backtrace/Backtrace.h>
 #include <backtrace/BacktraceMap.h>
+#if !defined(NO_LIBDEXFILE_SUPPORT)
+#include <unwindstack/DexFiles.h>
+#endif
 #include <unwindstack/Elf.h>
 #include <unwindstack/JitDebug.h>
 #include <unwindstack/Maps.h>
@@ -50,6 +53,12 @@
 
   const std::shared_ptr<unwindstack::Memory>& process_memory() { return process_memory_; }
 
+  unwindstack::JitDebug* GetJitDebug() { return jit_debug_.get(); }
+
+#if !defined(NO_LIBDEXFILE_SUPPORT)
+  unwindstack::DexFiles* GetDexFiles() { return dex_files_.get(); }
+#endif
+
   void SetArch(unwindstack::ArchEnum arch) { arch_ = arch; }
 
  protected:
@@ -57,6 +66,11 @@
 
   std::unique_ptr<unwindstack::Maps> stack_maps_;
   std::shared_ptr<unwindstack::Memory> process_memory_;
+  std::unique_ptr<unwindstack::JitDebug> jit_debug_;
+#if !defined(NO_LIBDEXFILE_SUPPORT)
+  std::unique_ptr<unwindstack::DexFiles> dex_files_;
+#endif
+
   unwindstack::ArchEnum arch_ = unwindstack::ARCH_UNKNOWN;
 };