diff --git a/include/backtrace/Backtrace.h b/include/backtrace/Backtrace.h
index f440bd2..290682a 100644
--- a/include/backtrace/Backtrace.h
+++ b/include/backtrace/Backtrace.h
@@ -52,12 +52,6 @@
 typedef ucontext ucontext_t;
 #endif
 
-struct backtrace_stackinfo_t {
-  uint64_t start;
-  uint64_t end;
-  const uint8_t* data;
-};
-
 class Backtrace {
 public:
   // Create the correct Backtrace object based on what is to be unwound.
@@ -72,14 +66,6 @@
   // If map is not NULL, the map is still owned by the caller.
   static Backtrace* Create(pid_t pid, pid_t tid, BacktraceMap* map = NULL);
 
-  // Create an offline Backtrace object that can be used to do an unwind without a process
-  // that is still running. If cache_file is set to true, then elf information will be cached
-  // for this call. The cached information survives until the calling process ends. This means
-  // that subsequent calls to create offline Backtrace objects will continue to use the same
-  // cache. It also assumes that the elf files used for each offline unwind are the same.
-  static Backtrace* CreateOffline(pid_t pid, pid_t tid, BacktraceMap* map,
-                                  const backtrace_stackinfo_t& stack, bool cache_file = false);
-
   virtual ~Backtrace();
 
   // Get the current stack trace and store in the backtrace_ structure.
diff --git a/include/backtrace/BacktraceMap.h b/include/backtrace/BacktraceMap.h
index 2373c45..bb18aa2 100644
--- a/include/backtrace/BacktraceMap.h
+++ b/include/backtrace/BacktraceMap.h
@@ -31,7 +31,6 @@
 
 #include <deque>
 #include <string>
-#include <vector>
 
 struct backtrace_map_t {
   uintptr_t start = 0;
@@ -49,8 +48,6 @@
   // is unsupported.
   static BacktraceMap* Create(pid_t pid, bool uncached = false);
 
-  static BacktraceMap* Create(pid_t pid, const std::vector<backtrace_map_t>& maps);
-
   virtual ~BacktraceMap();
 
   // Fill in the map data structure for the given address.
diff --git a/libbacktrace/Android.build.mk b/libbacktrace/Android.build.mk
index b15bf2b..4983b55 100644
--- a/libbacktrace/Android.build.mk
+++ b/libbacktrace/Android.build.mk
@@ -69,14 +69,7 @@
     $($(module)_ldlibs) \
     $($(module)_ldlibs_$(build_type)) \
 
-LOCAL_STRIP_MODULE := $($(module)_strip_module)
-
 ifeq ($(build_type),target)
-  ifneq (,$(filter $(LOCAL_SHARED_LIBRARIES),libLLVM))
-    LLVM_ROOT_PATH := external/llvm
-    include $(LLVM_ROOT_PATH)/llvm.mk
-    include $(LLVM_DEVICE_BUILD_MK)
-  endif
   include $(BUILD_$(build_target))
 endif
 
@@ -84,11 +77,6 @@
   # Only build if host builds are supported.
   ifeq ($(build_host),true)
     LOCAL_CFLAGS += -Wno-extern-c-compat -fno-omit-frame-pointer
-    ifneq (,$(filter $(LOCAL_SHARED_LIBRARIES),libLLVM))
-      LLVM_ROOT_PATH := external/llvm
-      include $(LLVM_ROOT_PATH)/llvm.mk
-      include $(LLVM_HOST_BUILD_MK)
-    endif
     include $(BUILD_HOST_$(build_target))
   endif
 endif
diff --git a/libbacktrace/Android.mk b/libbacktrace/Android.mk
index f9a1b52..395d677 100644
--- a/libbacktrace/Android.mk
+++ b/libbacktrace/Android.mk
@@ -25,7 +25,6 @@
 
 libbacktrace_common_cppflags := \
 	-std=gnu++11 \
-	-I external/libunwind/include/tdep \
 
 # The latest clang (r230699) does not allow SP/PC to be declared in inline asm lists.
 libbacktrace_common_clang_cflags += \
@@ -45,7 +44,6 @@
 	Backtrace.cpp \
 	BacktraceCurrent.cpp \
 	BacktraceMap.cpp \
-	BacktraceOffline.cpp \
 	BacktracePtrace.cpp \
 	thread_utils.c \
 	ThreadEntry.cpp \
@@ -55,7 +53,6 @@
 
 libbacktrace_shared_libraries := \
 	libbase \
-	libLLVM \
 	liblog \
 	libunwind \
 
@@ -89,8 +86,6 @@
 libbacktrace_test_src_files := \
 	backtrace_testlib.c \
 
-libbacktrace_test_strip_module := false
-
 module := libbacktrace_test
 module_tag := debug
 build_type := target
@@ -112,7 +107,6 @@
 	-DENABLE_PSS_TESTS \
 
 backtrace_test_src_files := \
-	backtrace_offline_test.cpp \
 	backtrace_test.cpp \
 	GetPss.cpp \
 	thread_utils.c \
@@ -126,8 +120,6 @@
 	libbacktrace \
 	libbase \
 	libcutils \
-	libLLVM \
-	libunwind \
 
 backtrace_test_shared_libraries_target += \
 	libdl \
@@ -135,8 +127,6 @@
 backtrace_test_ldlibs_host += \
 	-ldl \
 
-backtrace_test_strip_module := false
-
 module := backtrace_test
 module_tag := debug
 build_type := target
diff --git a/libbacktrace/Backtrace.cpp b/libbacktrace/Backtrace.cpp
index 9ead452..97f0ef4 100644
--- a/libbacktrace/Backtrace.cpp
+++ b/libbacktrace/Backtrace.cpp
@@ -30,7 +30,6 @@
 #include <cutils/threads.h>
 
 #include "BacktraceLog.h"
-#include "BacktraceOffline.h"
 #include "thread_utils.h"
 #include "UnwindCurrent.h"
 #include "UnwindPtrace.h"
@@ -141,8 +140,3 @@
     return new UnwindPtrace(pid, tid, map);
   }
 }
-
-Backtrace* Backtrace::CreateOffline(pid_t pid, pid_t tid, BacktraceMap* map,
-                                    const backtrace_stackinfo_t& stack, bool cache_file) {
-  return new BacktraceOffline(pid, tid, map, stack, cache_file);
-}
diff --git a/libbacktrace/BacktraceMap.cpp b/libbacktrace/BacktraceMap.cpp
index eac20fe..ca47f67 100644
--- a/libbacktrace/BacktraceMap.cpp
+++ b/libbacktrace/BacktraceMap.cpp
@@ -144,13 +144,3 @@
   return map;
 }
 #endif
-
-BacktraceMap* BacktraceMap::Create(pid_t pid, const std::vector<backtrace_map_t>& maps) {
-    BacktraceMap* backtrace_map = new BacktraceMap(pid);
-    backtrace_map->maps_.insert(backtrace_map->maps_.begin(), maps.begin(), maps.end());
-    std::sort(backtrace_map->maps_.begin(), backtrace_map->maps_.end(),
-            [](const backtrace_map_t& map1, const backtrace_map_t& map2) {
-              return map1.start < map2.start;
-            });
-    return backtrace_map;
-}
diff --git a/libbacktrace/BacktraceOffline.cpp b/libbacktrace/BacktraceOffline.cpp
deleted file mode 100644
index 27dfb83..0000000
--- a/libbacktrace/BacktraceOffline.cpp
+++ /dev/null
@@ -1,636 +0,0 @@
-/*
- * Copyright (C) 2015 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.
- */
-
-#include "BacktraceOffline.h"
-
-extern "C" {
-#define UNW_REMOTE_ONLY
-#include <dwarf.h>
-}
-
-#include <stdint.h>
-#include <string.h>
-#include <sys/types.h>
-#include <ucontext.h>
-#include <unistd.h>
-
-#include <string>
-#include <vector>
-
-#include <backtrace/Backtrace.h>
-#include <backtrace/BacktraceMap.h>
-
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wunused-parameter"
-
-#include <llvm/ADT/StringRef.h>
-#include <llvm/Object/Binary.h>
-#include <llvm/Object/ELFObjectFile.h>
-#include <llvm/Object/ObjectFile.h>
-
-#pragma clang diagnostic pop
-
-#include "BacktraceLog.h"
-
-void Space::Clear() {
-  start = 0;
-  end = 0;
-  data = nullptr;
-}
-
-size_t Space::Read(uint64_t addr, uint8_t* buffer, size_t size) {
-  if (addr >= start && addr < end) {
-    size_t read_size = std::min(size, static_cast<size_t>(end - addr));
-    memcpy(buffer, data + (addr - start), read_size);
-    return read_size;
-  }
-  return 0;
-}
-
-static int FindProcInfo(unw_addr_space_t addr_space, unw_word_t ip, unw_proc_info* proc_info,
-                        int need_unwind_info, void* arg) {
-  BacktraceOffline* backtrace = reinterpret_cast<BacktraceOffline*>(arg);
-  bool result = backtrace->FindProcInfo(addr_space, ip, proc_info, need_unwind_info);
-  return result ? 0 : -UNW_EINVAL;
-}
-
-static void PutUnwindInfo(unw_addr_space_t, unw_proc_info_t*, void*) {
-}
-
-static int GetDynInfoListAddr(unw_addr_space_t, unw_word_t*, void*) {
-  return -UNW_ENOINFO;
-}
-
-static int AccessMem(unw_addr_space_t, unw_word_t addr, unw_word_t* value, int write, void* arg) {
-  if (write == 1) {
-    return -UNW_EINVAL;
-  }
-  BacktraceOffline* backtrace = reinterpret_cast<BacktraceOffline*>(arg);
-  *value = 0;
-  size_t read_size = backtrace->Read(addr, reinterpret_cast<uint8_t*>(value), sizeof(unw_word_t));
-  // Strictly we should check if read_size matches sizeof(unw_word_t), but it is possible in
-  // .eh_frame_hdr that the section can end at a position not aligned in sizeof(unw_word_t), and
-  // we should permit the read at the end of the section.
-  return (read_size > 0u ? 0 : -UNW_EINVAL);
-}
-
-static int AccessReg(unw_addr_space_t, unw_regnum_t unwind_reg, unw_word_t* value, int write,
-                     void* arg) {
-  if (write == 1) {
-    return -UNW_EINVAL;
-  }
-  BacktraceOffline* backtrace = reinterpret_cast<BacktraceOffline*>(arg);
-  uint64_t reg_value;
-  bool result = backtrace->ReadReg(unwind_reg, &reg_value);
-  if (result) {
-    *value = static_cast<unw_word_t>(reg_value);
-  }
-  return result ? 0 : -UNW_EINVAL;
-}
-
-static int AccessFpReg(unw_addr_space_t, unw_regnum_t, unw_fpreg_t*, int, void*) {
-  return -UNW_EINVAL;
-}
-
-static int Resume(unw_addr_space_t, unw_cursor_t*, void*) {
-  return -UNW_EINVAL;
-}
-
-static int GetProcName(unw_addr_space_t, unw_word_t, char*, size_t, unw_word_t*, void*) {
-  return -UNW_EINVAL;
-}
-
-static unw_accessors_t accessors = {
-    .find_proc_info = FindProcInfo,
-    .put_unwind_info = PutUnwindInfo,
-    .get_dyn_info_list_addr = GetDynInfoListAddr,
-    .access_mem = AccessMem,
-    .access_reg = AccessReg,
-    .access_fpreg = AccessFpReg,
-    .resume = Resume,
-    .get_proc_name = GetProcName,
-};
-
-bool BacktraceOffline::Unwind(size_t num_ignore_frames, ucontext_t* context) {
-  if (context == nullptr) {
-    BACK_LOGW("The context is needed for offline backtracing.");
-    return false;
-  }
-  context_ = context;
-
-  unw_addr_space_t addr_space = unw_create_addr_space(&accessors, 0);
-  unw_cursor_t cursor;
-  int ret = unw_init_remote(&cursor, addr_space, this);
-  if (ret != 0) {
-    BACK_LOGW("unw_init_remote failed %d", ret);
-    unw_destroy_addr_space(addr_space);
-    return false;
-  }
-  size_t num_frames = 0;
-  do {
-    unw_word_t pc;
-    ret = unw_get_reg(&cursor, UNW_REG_IP, &pc);
-    if (ret < 0) {
-      BACK_LOGW("Failed to read IP %d", ret);
-      break;
-    }
-    unw_word_t sp;
-    ret = unw_get_reg(&cursor, UNW_REG_SP, &sp);
-    if (ret < 0) {
-      BACK_LOGW("Failed to read SP %d", ret);
-      break;
-    }
-
-    if (num_ignore_frames == 0) {
-      frames_.resize(num_frames + 1);
-      backtrace_frame_data_t* frame = &frames_[num_frames];
-      frame->num = num_frames;
-      frame->pc = static_cast<uintptr_t>(pc);
-      frame->sp = static_cast<uintptr_t>(sp);
-      frame->stack_size = 0;
-
-      if (num_frames > 0) {
-        backtrace_frame_data_t* prev = &frames_[num_frames - 1];
-        prev->stack_size = frame->sp - prev->sp;
-      }
-      frame->func_name = GetFunctionName(frame->pc, &frame->func_offset);
-      FillInMap(frame->pc, &frame->map);
-      num_frames++;
-    } else {
-      num_ignore_frames--;
-    }
-    ret = unw_step(&cursor);
-  } while (ret > 0 && num_frames < MAX_BACKTRACE_FRAMES);
-
-  unw_destroy_addr_space(addr_space);
-  context_ = nullptr;
-  return true;
-}
-
-bool BacktraceOffline::ReadWord(uintptr_t ptr, word_t* out_value) {
-  size_t bytes_read = Read(ptr, reinterpret_cast<uint8_t*>(out_value), sizeof(word_t));
-  return bytes_read == sizeof(word_t);
-}
-
-size_t BacktraceOffline::Read(uintptr_t addr, uint8_t* buffer, size_t bytes) {
-  // Normally, libunwind needs stack information and call frame information to do remote unwinding.
-  // If call frame information is stored in .debug_frame, libunwind can read it from file
-  // by itself. If call frame information is stored in .eh_frame, we need to provide data in
-  // .eh_frame/.eh_frame_hdr sections.
-  // The order of readings below doesn't matter, as the spaces don't overlap with each other.
-  size_t read_size = eh_frame_hdr_space_.Read(addr, buffer, bytes);
-  if (read_size != 0) {
-    return read_size;
-  }
-  read_size = eh_frame_space_.Read(addr, buffer, bytes);
-  if (read_size != 0) {
-    return read_size;
-  }
-  read_size = stack_space_.Read(addr, buffer, bytes);
-  return read_size;
-}
-
-static bool FileOffsetToVaddr(
-    const std::vector<DebugFrameInfo::EhFrame::ProgramHeader>& program_headers,
-    uint64_t file_offset, uint64_t* vaddr) {
-  for (auto& header : program_headers) {
-    if (file_offset >= header.file_offset && file_offset < header.file_offset + header.file_size) {
-      // TODO: Consider load_bias?
-      *vaddr = file_offset - header.file_offset + header.vaddr;
-      return true;
-    }
-  }
-  return false;
-}
-
-bool BacktraceOffline::FindProcInfo(unw_addr_space_t addr_space, uint64_t ip,
-                                    unw_proc_info_t* proc_info, int need_unwind_info) {
-  backtrace_map_t map;
-  FillInMap(ip, &map);
-  if (!BacktraceMap::IsValid(map)) {
-    return false;
-  }
-  const std::string& filename = map.name;
-  DebugFrameInfo* debug_frame = GetDebugFrameInFile(filename);
-  if (debug_frame == nullptr) {
-    return false;
-  }
-  if (debug_frame->is_eh_frame) {
-    uint64_t ip_offset = ip - map.start + map.offset;
-    uint64_t ip_vaddr;  // vaddr in the elf file.
-    bool result = FileOffsetToVaddr(debug_frame->eh_frame.program_headers, ip_offset, &ip_vaddr);
-    if (!result) {
-      return false;
-    }
-    // Calculate the addresses where .eh_frame_hdr and .eh_frame stay when the process was running.
-    eh_frame_hdr_space_.start = (ip - ip_vaddr) + debug_frame->eh_frame.eh_frame_hdr_vaddr;
-    eh_frame_hdr_space_.end =
-        eh_frame_hdr_space_.start + debug_frame->eh_frame.eh_frame_hdr_data.size();
-    eh_frame_hdr_space_.data = debug_frame->eh_frame.eh_frame_hdr_data.data();
-
-    eh_frame_space_.start = (ip - ip_vaddr) + debug_frame->eh_frame.eh_frame_vaddr;
-    eh_frame_space_.end = eh_frame_space_.start + debug_frame->eh_frame.eh_frame_data.size();
-    eh_frame_space_.data = debug_frame->eh_frame.eh_frame_data.data();
-
-    unw_dyn_info di;
-    memset(&di, '\0', sizeof(di));
-    di.start_ip = map.start;
-    di.end_ip = map.end;
-    di.format = UNW_INFO_FORMAT_REMOTE_TABLE;
-    di.u.rti.name_ptr = 0;
-    di.u.rti.segbase = eh_frame_hdr_space_.start;
-    di.u.rti.table_data =
-        eh_frame_hdr_space_.start + debug_frame->eh_frame.fde_table_offset_in_eh_frame_hdr;
-    di.u.rti.table_len = (eh_frame_hdr_space_.end - di.u.rti.table_data) / sizeof(unw_word_t);
-    int ret = dwarf_search_unwind_table(addr_space, ip, &di, proc_info, need_unwind_info, this);
-    return ret == 0;
-  }
-
-  eh_frame_hdr_space_.Clear();
-  eh_frame_space_.Clear();
-  unw_dyn_info_t di;
-  unw_word_t segbase = map.start - map.offset;
-  int found = dwarf_find_debug_frame(0, &di, ip, segbase, filename.c_str(), map.start, map.end);
-  if (found == 1) {
-    int ret = dwarf_search_unwind_table(addr_space, ip, &di, proc_info, need_unwind_info, this);
-    return ret == 0;
-  }
-  return false;
-}
-
-bool BacktraceOffline::ReadReg(size_t reg, uint64_t* value) {
-  bool result = true;
-#if defined(__arm__)
-  switch (reg) {
-    case UNW_ARM_R0:
-      *value = context_->uc_mcontext.arm_r0;
-      break;
-    case UNW_ARM_R1:
-      *value = context_->uc_mcontext.arm_r1;
-      break;
-    case UNW_ARM_R2:
-      *value = context_->uc_mcontext.arm_r2;
-      break;
-    case UNW_ARM_R3:
-      *value = context_->uc_mcontext.arm_r3;
-      break;
-    case UNW_ARM_R4:
-      *value = context_->uc_mcontext.arm_r4;
-      break;
-    case UNW_ARM_R5:
-      *value = context_->uc_mcontext.arm_r5;
-      break;
-    case UNW_ARM_R6:
-      *value = context_->uc_mcontext.arm_r6;
-      break;
-    case UNW_ARM_R7:
-      *value = context_->uc_mcontext.arm_r7;
-      break;
-    case UNW_ARM_R8:
-      *value = context_->uc_mcontext.arm_r8;
-      break;
-    case UNW_ARM_R9:
-      *value = context_->uc_mcontext.arm_r9;
-      break;
-    case UNW_ARM_R10:
-      *value = context_->uc_mcontext.arm_r10;
-      break;
-    case UNW_ARM_R11:
-      *value = context_->uc_mcontext.arm_fp;
-      break;
-    case UNW_ARM_R12:
-      *value = context_->uc_mcontext.arm_ip;
-      break;
-    case UNW_ARM_R13:
-      *value = context_->uc_mcontext.arm_sp;
-      break;
-    case UNW_ARM_R14:
-      *value = context_->uc_mcontext.arm_lr;
-      break;
-    case UNW_ARM_R15:
-      *value = context_->uc_mcontext.arm_pc;
-      break;
-    default:
-      result = false;
-  }
-#elif defined(__aarch64__)
-  if (reg <= UNW_AARCH64_PC) {
-    *value = context_->uc_mcontext.regs[reg];
-  } else {
-    result = false;
-  }
-#elif defined(__x86_64__)
-  switch (reg) {
-    case UNW_X86_64_R8:
-      *value = context_->uc_mcontext.gregs[REG_R8];
-      break;
-    case UNW_X86_64_R9:
-      *value = context_->uc_mcontext.gregs[REG_R9];
-      break;
-    case UNW_X86_64_R10:
-      *value = context_->uc_mcontext.gregs[REG_R10];
-      break;
-    case UNW_X86_64_R11:
-      *value = context_->uc_mcontext.gregs[REG_R11];
-      break;
-    case UNW_X86_64_R12:
-      *value = context_->uc_mcontext.gregs[REG_R12];
-      break;
-    case UNW_X86_64_R13:
-      *value = context_->uc_mcontext.gregs[REG_R13];
-      break;
-    case UNW_X86_64_R14:
-      *value = context_->uc_mcontext.gregs[REG_R14];
-      break;
-    case UNW_X86_64_R15:
-      *value = context_->uc_mcontext.gregs[REG_R15];
-      break;
-    case UNW_X86_64_RDI:
-      *value = context_->uc_mcontext.gregs[REG_RDI];
-      break;
-    case UNW_X86_64_RSI:
-      *value = context_->uc_mcontext.gregs[REG_RSI];
-      break;
-    case UNW_X86_64_RBP:
-      *value = context_->uc_mcontext.gregs[REG_RBP];
-      break;
-    case UNW_X86_64_RBX:
-      *value = context_->uc_mcontext.gregs[REG_RBX];
-      break;
-    case UNW_X86_64_RDX:
-      *value = context_->uc_mcontext.gregs[REG_RDX];
-      break;
-    case UNW_X86_64_RAX:
-      *value = context_->uc_mcontext.gregs[REG_RAX];
-      break;
-    case UNW_X86_64_RCX:
-      *value = context_->uc_mcontext.gregs[REG_RCX];
-      break;
-    case UNW_X86_64_RSP:
-      *value = context_->uc_mcontext.gregs[REG_RSP];
-      break;
-    case UNW_X86_64_RIP:
-      *value = context_->uc_mcontext.gregs[REG_RIP];
-      break;
-    default:
-      result = false;
-  }
-#elif defined(__i386__)
-  switch (reg) {
-    case UNW_X86_GS:
-      *value = context_->uc_mcontext.gregs[REG_GS];
-      break;
-    case UNW_X86_FS:
-      *value = context_->uc_mcontext.gregs[REG_FS];
-      break;
-    case UNW_X86_ES:
-      *value = context_->uc_mcontext.gregs[REG_ES];
-      break;
-    case UNW_X86_DS:
-      *value = context_->uc_mcontext.gregs[REG_DS];
-      break;
-    case UNW_X86_EAX:
-      *value = context_->uc_mcontext.gregs[REG_EAX];
-      break;
-    case UNW_X86_EBX:
-      *value = context_->uc_mcontext.gregs[REG_EBX];
-      break;
-    case UNW_X86_ECX:
-      *value = context_->uc_mcontext.gregs[REG_ECX];
-      break;
-    case UNW_X86_EDX:
-      *value = context_->uc_mcontext.gregs[REG_EDX];
-      break;
-    case UNW_X86_ESI:
-      *value = context_->uc_mcontext.gregs[REG_ESI];
-      break;
-    case UNW_X86_EDI:
-      *value = context_->uc_mcontext.gregs[REG_EDI];
-      break;
-    case UNW_X86_EBP:
-      *value = context_->uc_mcontext.gregs[REG_EBP];
-      break;
-    case UNW_X86_EIP:
-      *value = context_->uc_mcontext.gregs[REG_EIP];
-      break;
-    case UNW_X86_ESP:
-      *value = context_->uc_mcontext.gregs[REG_ESP];
-      break;
-    case UNW_X86_TRAPNO:
-      *value = context_->uc_mcontext.gregs[REG_TRAPNO];
-      break;
-    case UNW_X86_CS:
-      *value = context_->uc_mcontext.gregs[REG_CS];
-      break;
-    case UNW_X86_EFLAGS:
-      *value = context_->uc_mcontext.gregs[REG_EFL];
-      break;
-    case UNW_X86_SS:
-      *value = context_->uc_mcontext.gregs[REG_SS];
-      break;
-    default:
-      result = false;
-  }
-#endif
-  return result;
-}
-
-std::string BacktraceOffline::GetFunctionNameRaw(uintptr_t, uintptr_t* offset) {
-  // We don't have enough information to support this. And it is expensive.
-  *offset = 0;
-  return "";
-}
-
-std::unordered_map<std::string, std::unique_ptr<DebugFrameInfo>> BacktraceOffline::debug_frames_;
-std::unordered_set<std::string> BacktraceOffline::debug_frame_missing_files_;
-
-static DebugFrameInfo* ReadDebugFrameFromFile(const std::string& filename);
-
-DebugFrameInfo* BacktraceOffline::GetDebugFrameInFile(const std::string& filename) {
-  if (cache_file_) {
-    auto it = debug_frames_.find(filename);
-    if (it != debug_frames_.end()) {
-      return it->second.get();
-    }
-    if (debug_frame_missing_files_.find(filename) != debug_frame_missing_files_.end()) {
-      return nullptr;
-    }
-  }
-  DebugFrameInfo* debug_frame = ReadDebugFrameFromFile(filename);
-  if (cache_file_) {
-    if (debug_frame != nullptr) {
-      debug_frames_.emplace(filename, std::unique_ptr<DebugFrameInfo>(debug_frame));
-    } else {
-      debug_frame_missing_files_.insert(filename);
-    }
-  } else {
-    if (last_debug_frame_ != nullptr) {
-      delete last_debug_frame_;
-    }
-    last_debug_frame_ = debug_frame;
-  }
-  return debug_frame;
-}
-
-static bool OmitEncodedValue(uint8_t encode, const uint8_t*& p) {
-  if (encode == DW_EH_PE_omit) {
-    return 0;
-  }
-  uint8_t format = encode & 0x0f;
-  switch (format) {
-    case DW_EH_PE_ptr:
-      p += sizeof(unw_word_t);
-      break;
-    case DW_EH_PE_uleb128:
-    case DW_EH_PE_sleb128:
-      while ((*p & 0x80) != 0) {
-        ++p;
-      }
-      ++p;
-      break;
-    case DW_EH_PE_udata2:
-    case DW_EH_PE_sdata2:
-      p += 2;
-      break;
-    case DW_EH_PE_udata4:
-    case DW_EH_PE_sdata4:
-      p += 4;
-      break;
-    case DW_EH_PE_udata8:
-    case DW_EH_PE_sdata8:
-      p += 8;
-      break;
-    default:
-      return false;
-  }
-  return true;
-}
-
-static bool GetFdeTableOffsetInEhFrameHdr(const std::vector<uint8_t>& data,
-                                          uint64_t* table_offset_in_eh_frame_hdr) {
-  const uint8_t* p = data.data();
-  const uint8_t* end = p + data.size();
-  if (p + 4 > end) {
-    return false;
-  }
-  uint8_t version = *p++;
-  if (version != 1) {
-    return false;
-  }
-  uint8_t eh_frame_ptr_encode = *p++;
-  uint8_t fde_count_encode = *p++;
-  uint8_t fde_table_encode = *p++;
-
-  if (fde_table_encode != (DW_EH_PE_datarel | DW_EH_PE_sdata4)) {
-    return false;
-  }
-
-  if (!OmitEncodedValue(eh_frame_ptr_encode, p) || !OmitEncodedValue(fde_count_encode, p)) {
-    return false;
-  }
-  if (p >= end) {
-    return false;
-  }
-  *table_offset_in_eh_frame_hdr = p - data.data();
-  return true;
-}
-
-using ProgramHeader = DebugFrameInfo::EhFrame::ProgramHeader;
-
-template <class ELFT>
-DebugFrameInfo* ReadDebugFrameFromELFFile(const llvm::object::ELFFile<ELFT>* elf) {
-  bool has_eh_frame_hdr = false;
-  uint64_t eh_frame_hdr_vaddr = 0;
-  std::vector<uint8_t> eh_frame_hdr_data;
-  bool has_eh_frame = false;
-  uint64_t eh_frame_vaddr = 0;
-  std::vector<uint8_t> eh_frame_data;
-
-  for (auto it = elf->begin_sections(); it != elf->end_sections(); ++it) {
-    llvm::ErrorOr<llvm::StringRef> name = elf->getSectionName(&*it);
-    if (name) {
-      if (name.get() == ".debug_frame") {
-        DebugFrameInfo* debug_frame = new DebugFrameInfo;
-        debug_frame->is_eh_frame = false;
-        return debug_frame;
-      }
-      if (name.get() == ".eh_frame_hdr") {
-        has_eh_frame_hdr = true;
-        eh_frame_hdr_vaddr = it->sh_addr;
-        llvm::ErrorOr<llvm::ArrayRef<uint8_t>> data = elf->getSectionContents(&*it);
-        if (data) {
-          eh_frame_hdr_data.insert(eh_frame_hdr_data.begin(), data->data(),
-                                   data->data() + data->size());
-        } else {
-          return nullptr;
-        }
-      } else if (name.get() == ".eh_frame") {
-        has_eh_frame = true;
-        eh_frame_vaddr = it->sh_addr;
-        llvm::ErrorOr<llvm::ArrayRef<uint8_t>> data = elf->getSectionContents(&*it);
-        if (data) {
-          eh_frame_data.insert(eh_frame_data.begin(), data->data(), data->data() + data->size());
-        } else {
-          return nullptr;
-        }
-      }
-    }
-  }
-  if (!(has_eh_frame_hdr && has_eh_frame)) {
-    return nullptr;
-  }
-  uint64_t fde_table_offset;
-  if (!GetFdeTableOffsetInEhFrameHdr(eh_frame_hdr_data, &fde_table_offset)) {
-    return nullptr;
-  }
-
-  std::vector<ProgramHeader> program_headers;
-  for (auto it = elf->begin_program_headers(); it != elf->end_program_headers(); ++it) {
-    ProgramHeader header;
-    header.vaddr = it->p_vaddr;
-    header.file_offset = it->p_offset;
-    header.file_size = it->p_filesz;
-    program_headers.push_back(header);
-  }
-  DebugFrameInfo* debug_frame = new DebugFrameInfo;
-  debug_frame->is_eh_frame = true;
-  debug_frame->eh_frame.eh_frame_hdr_vaddr = eh_frame_hdr_vaddr;
-  debug_frame->eh_frame.eh_frame_vaddr = eh_frame_vaddr;
-  debug_frame->eh_frame.fde_table_offset_in_eh_frame_hdr = fde_table_offset;
-  debug_frame->eh_frame.eh_frame_hdr_data = std::move(eh_frame_hdr_data);
-  debug_frame->eh_frame.eh_frame_data = std::move(eh_frame_data);
-  debug_frame->eh_frame.program_headers = program_headers;
-  return debug_frame;
-}
-
-static DebugFrameInfo* ReadDebugFrameFromFile(const std::string& filename) {
-  auto owning_binary = llvm::object::createBinary(llvm::StringRef(filename));
-  if (owning_binary.getError()) {
-    return nullptr;
-  }
-  llvm::object::Binary* binary = owning_binary.get().getBinary();
-  auto obj = llvm::dyn_cast<llvm::object::ObjectFile>(binary);
-  if (obj == nullptr) {
-    return nullptr;
-  }
-  if (auto elf = llvm::dyn_cast<llvm::object::ELF32LEObjectFile>(obj)) {
-    return ReadDebugFrameFromELFFile(elf->getELFFile());
-  }
-  if (auto elf = llvm::dyn_cast<llvm::object::ELF64LEObjectFile>(obj)) {
-    return ReadDebugFrameFromELFFile(elf->getELFFile());
-  }
-  return nullptr;
-}
diff --git a/libbacktrace/BacktraceOffline.h b/libbacktrace/BacktraceOffline.h
deleted file mode 100644
index 42f826d..0000000
--- a/libbacktrace/BacktraceOffline.h
+++ /dev/null
@@ -1,105 +0,0 @@
-/*
- * Copyright (C) 2015 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 _LIBBACKTRACE_UNWIND_OFFLINE_H
-#define _LIBBACKTRACE_UNWIND_OFFLINE_H
-
-#include <libunwind.h>
-#include <stdint.h>
-#include <sys/types.h>
-#include <ucontext.h>
-
-#include <unordered_map>
-#include <unordered_set>
-
-#include <backtrace/Backtrace.h>
-
-struct Space {
-  uint64_t start;
-  uint64_t end;
-  const uint8_t* data;
-
-  Space() {
-    Clear();
-  }
-
-  void Clear();
-  size_t Read(uint64_t addr, uint8_t* buffer, size_t size);
-};
-
-struct DebugFrameInfo {
-  bool is_eh_frame;
-  struct EhFrame {
-    uint64_t eh_frame_hdr_vaddr;
-    uint64_t eh_frame_vaddr;
-    uint64_t fde_table_offset_in_eh_frame_hdr;
-    std::vector<uint8_t> eh_frame_hdr_data;
-    std::vector<uint8_t> eh_frame_data;
-    struct ProgramHeader {
-      uint64_t vaddr;
-      uint64_t file_offset;
-      uint64_t file_size;
-    };
-    std::vector<ProgramHeader> program_headers;
-  } eh_frame;
-};
-
-class BacktraceOffline : public Backtrace {
- public:
-  BacktraceOffline(pid_t pid, pid_t tid, BacktraceMap* map, const backtrace_stackinfo_t& stack,
-                   bool cache_file)
-      : Backtrace(pid, tid, map),
-        cache_file_(cache_file),
-        context_(nullptr),
-        last_debug_frame_(nullptr) {
-    stack_space_.start = stack.start;
-    stack_space_.end = stack.end;
-    stack_space_.data = stack.data;
-  }
-
-  virtual ~BacktraceOffline() {
-    if (last_debug_frame_ != nullptr) {
-      delete last_debug_frame_;
-    }
-  }
-
-  bool Unwind(size_t num_ignore_frames, ucontext_t* context) override;
-
-  bool ReadWord(uintptr_t ptr, word_t* out_value) override;
-
-  size_t Read(uintptr_t addr, uint8_t* buffer, size_t bytes) override;
-
-  bool FindProcInfo(unw_addr_space_t addr_space, uint64_t ip, unw_proc_info_t* proc_info,
-                    int need_unwind_info);
-
-  bool ReadReg(size_t reg_index, uint64_t* value);
-
- protected:
-  std::string GetFunctionNameRaw(uintptr_t pc, uintptr_t* offset) override;
-  DebugFrameInfo* GetDebugFrameInFile(const std::string& filename);
-
-  static std::unordered_map<std::string, std::unique_ptr<DebugFrameInfo>> debug_frames_;
-  static std::unordered_set<std::string> debug_frame_missing_files_;
-
-  bool cache_file_;
-  ucontext_t* context_;
-  Space eh_frame_hdr_space_;
-  Space eh_frame_space_;
-  Space stack_space_;
-  DebugFrameInfo* last_debug_frame_;
-};
-
-#endif  // _LIBBACKTRACE_BACKTRACE_OFFLINE_H
diff --git a/libbacktrace/backtrace_offline_test.cpp b/libbacktrace/backtrace_offline_test.cpp
deleted file mode 100644
index 88a3533..0000000
--- a/libbacktrace/backtrace_offline_test.cpp
+++ /dev/null
@@ -1,189 +0,0 @@
-#include <libunwind.h>
-#include <pthread.h>
-#include <stdint.h>
-#include <string.h>
-
-#include <functional>
-#include <memory>
-#include <string>
-#include <utility>
-#include <vector>
-
-#include <backtrace/Backtrace.h>
-#include <backtrace/BacktraceMap.h>
-#include <cutils/threads.h>
-
-#include <gtest/gtest.h>
-
-extern "C" {
-// Prototypes for functions in the test library.
-int test_level_one(int, int, int, int, void (*)(void*), void*);
-int test_level_two(int, int, int, int, void (*)(void*), void*);
-int test_level_three(int, int, int, int, void (*)(void*), void*);
-int test_level_four(int, int, int, int, void (*)(void*), void*);
-int test_recursive_call(int, void (*)(void*), void*);
-}
-
-static volatile bool g_exit_flag = false;
-
-static void GetContextAndExit(void* arg) {
-  unw_context_t* unw_context = reinterpret_cast<unw_context_t*>(arg);
-  unw_getcontext(unw_context);
-  // Don't touch the stack anymore.
-  while (!g_exit_flag) {
-  }
-}
-
-struct OfflineThreadArg {
-  unw_context_t unw_context;
-  pid_t tid;
-  std::function<int(void (*)(void*), void*)> function;
-};
-
-static void* OfflineThreadFunc(void* arg) {
-  OfflineThreadArg* fn_arg = reinterpret_cast<OfflineThreadArg*>(arg);
-  fn_arg->tid = gettid();
-  fn_arg->function(GetContextAndExit, &fn_arg->unw_context);
-  return nullptr;
-}
-
-static ucontext_t GetUContextFromUnwContext(const unw_context_t& unw_context) {
-  ucontext_t ucontext;
-  memset(&ucontext, 0, sizeof(ucontext));
-#if defined(__arm__)
-  ucontext.uc_mcontext.arm_r0 = unw_context.regs[0];
-  ucontext.uc_mcontext.arm_r1 = unw_context.regs[1];
-  ucontext.uc_mcontext.arm_r2 = unw_context.regs[2];
-  ucontext.uc_mcontext.arm_r3 = unw_context.regs[3];
-  ucontext.uc_mcontext.arm_r4 = unw_context.regs[4];
-  ucontext.uc_mcontext.arm_r5 = unw_context.regs[5];
-  ucontext.uc_mcontext.arm_r6 = unw_context.regs[6];
-  ucontext.uc_mcontext.arm_r7 = unw_context.regs[7];
-  ucontext.uc_mcontext.arm_r8 = unw_context.regs[8];
-  ucontext.uc_mcontext.arm_r9 = unw_context.regs[9];
-  ucontext.uc_mcontext.arm_r10 = unw_context.regs[10];
-  ucontext.uc_mcontext.arm_fp = unw_context.regs[11];
-  ucontext.uc_mcontext.arm_ip = unw_context.regs[12];
-  ucontext.uc_mcontext.arm_sp = unw_context.regs[13];
-  ucontext.uc_mcontext.arm_lr = unw_context.regs[14];
-  ucontext.uc_mcontext.arm_pc = unw_context.regs[15];
-#else
-  ucontext.uc_mcontext = unw_context.uc_mcontext;
-#endif
-  return ucontext;
-}
-
-static void OfflineBacktraceFunctionCall(std::function<int(void (*)(void*), void*)> function,
-                                         std::vector<uintptr_t>* pc_values) {
-  // Create a thread to generate the needed stack and registers information.
-  g_exit_flag = false;
-  const size_t stack_size = 1024 * 1024;
-  void* stack = mmap(NULL, stack_size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
-  ASSERT_NE(MAP_FAILED, stack);
-  uintptr_t stack_addr = reinterpret_cast<uintptr_t>(stack);
-  pthread_attr_t attr;
-  ASSERT_EQ(0, pthread_attr_init(&attr));
-  ASSERT_EQ(0, pthread_attr_setstack(&attr, reinterpret_cast<void*>(stack), stack_size));
-  pthread_t thread;
-  OfflineThreadArg arg;
-  arg.function = function;
-  ASSERT_EQ(0, pthread_create(&thread, &attr, OfflineThreadFunc, &arg));
-  // Wait for the offline thread to generate the stack and unw_context information.
-  sleep(1);
-  // Copy the stack information.
-  std::vector<uint8_t> stack_data(reinterpret_cast<uint8_t*>(stack),
-                                  reinterpret_cast<uint8_t*>(stack) + stack_size);
-  g_exit_flag = true;
-  ASSERT_EQ(0, pthread_join(thread, nullptr));
-  ASSERT_EQ(0, munmap(stack, stack_size));
-
-  // Do offline backtrace.
-  std::unique_ptr<BacktraceMap> map(BacktraceMap::Create(getpid()));
-  ASSERT_TRUE(map != nullptr);
-
-  backtrace_stackinfo_t stack_info;
-  stack_info.start = stack_addr;
-  stack_info.end = stack_addr + stack_size;
-  stack_info.data = stack_data.data();
-
-  std::unique_ptr<Backtrace> backtrace(
-      Backtrace::CreateOffline(getpid(), arg.tid, map.get(), stack_info));
-  ASSERT_TRUE(backtrace != nullptr);
-
-  ucontext_t ucontext = GetUContextFromUnwContext(arg.unw_context);
-  ASSERT_TRUE(backtrace->Unwind(0, &ucontext));
-
-  // Collect pc values of the call stack frames.
-  for (size_t i = 0; i < backtrace->NumFrames(); ++i) {
-    pc_values->push_back(backtrace->GetFrame(i)->pc);
-  }
-}
-
-// Return the name of the function which matches the address. Although we don't know the
-// exact end of each function, it is accurate enough for the tests.
-static std::string FunctionNameForAddress(uintptr_t addr) {
-  struct FunctionSymbol {
-    std::string name;
-    uintptr_t start;
-    uintptr_t end;
-  };
-
-  static std::vector<FunctionSymbol> symbols;
-  if (symbols.empty()) {
-    symbols = std::vector<FunctionSymbol>{
-        {"unknown_start", 0, 0},
-        {"test_level_one", reinterpret_cast<uintptr_t>(&test_level_one), 0},
-        {"test_level_two", reinterpret_cast<uintptr_t>(&test_level_two), 0},
-        {"test_level_three", reinterpret_cast<uintptr_t>(&test_level_three), 0},
-        {"test_level_four", reinterpret_cast<uintptr_t>(&test_level_four), 0},
-        {"test_recursive_call", reinterpret_cast<uintptr_t>(&test_recursive_call), 0},
-        {"GetContextAndExit", reinterpret_cast<uintptr_t>(&GetContextAndExit), 0},
-        {"unknown_end", static_cast<uintptr_t>(-1), static_cast<uintptr_t>(-1)},
-    };
-    std::sort(
-        symbols.begin(), symbols.end(),
-        [](const FunctionSymbol& s1, const FunctionSymbol& s2) { return s1.start < s2.start; });
-    for (size_t i = 0; i + 1 < symbols.size(); ++i) {
-      symbols[i].end = symbols[i + 1].start;
-    }
-  }
-  for (auto& symbol : symbols) {
-    if (addr >= symbol.start && addr < symbol.end) {
-      return symbol.name;
-    }
-  }
-  return "";
-}
-
-TEST(libbacktrace, offline) {
-  std::function<int(void (*)(void*), void*)> function =
-      std::bind(test_level_one, 1, 2, 3, 4, std::placeholders::_1, std::placeholders::_2);
-  std::vector<uintptr_t> pc_values;
-  OfflineBacktraceFunctionCall(function, &pc_values);
-  ASSERT_FALSE(pc_values.empty());
-  ASSERT_LE(pc_values.size(), static_cast<size_t>(MAX_BACKTRACE_FRAMES));
-
-  size_t test_one_index = 0;
-  for (size_t i = 0; i < pc_values.size(); ++i) {
-    if (FunctionNameForAddress(pc_values[i]) == "test_level_one") {
-      test_one_index = i;
-      break;
-    }
-  }
-
-  ASSERT_GE(test_one_index, 3u);
-  ASSERT_EQ("test_level_one", FunctionNameForAddress(pc_values[test_one_index]));
-  ASSERT_EQ("test_level_two", FunctionNameForAddress(pc_values[test_one_index - 1]));
-  ASSERT_EQ("test_level_three", FunctionNameForAddress(pc_values[test_one_index - 2]));
-  ASSERT_EQ("test_level_four", FunctionNameForAddress(pc_values[test_one_index - 3]));
-}
-
-TEST(libbacktrace, offline_max_trace) {
-  std::function<int(void (*)(void*), void*)> function = std::bind(
-      test_recursive_call, MAX_BACKTRACE_FRAMES + 10, std::placeholders::_1, std::placeholders::_2);
-  std::vector<uintptr_t> pc_values;
-  OfflineBacktraceFunctionCall(function, &pc_values);
-  ASSERT_FALSE(pc_values.empty());
-  ASSERT_EQ(static_cast<size_t>(MAX_BACKTRACE_FRAMES), pc_values.size());
-  ASSERT_EQ("test_recursive_call", FunctionNameForAddress(pc_values.back()));
-}