diff --git a/base/file.cpp b/base/file.cpp
index 81b04d7..378a405 100644
--- a/base/file.cpp
+++ b/base/file.cpp
@@ -212,6 +212,20 @@
 }
 #endif
 
+#if !defined(_WIN32)
+bool Realpath(const std::string& path, std::string* result) {
+  result->clear();
+
+  char* realpath_buf = realpath(path.c_str(), nullptr);
+  if (realpath_buf == nullptr) {
+    return false;
+  }
+  result->assign(realpath_buf);
+  free(realpath_buf);
+  return true;
+}
+#endif
+
 std::string GetExecutablePath() {
 #if defined(__linux__)
   std::string path;
diff --git a/base/file_test.cpp b/base/file_test.cpp
index 1021326..266131e 100644
--- a/base/file_test.cpp
+++ b/base/file_test.cpp
@@ -159,6 +159,38 @@
 #endif
 }
 
+TEST(file, Realpath) {
+#if !defined(_WIN32)
+  TemporaryDir td;
+  std::string basename = android::base::Basename(td.path);
+  std::string dir_name = android::base::Dirname(td.path);
+  std::string base_dir_name = android::base::Basename(dir_name);
+
+  {
+    std::string path = dir_name + "/../" + base_dir_name + "/" + basename;
+    std::string result;
+    ASSERT_TRUE(android::base::Realpath(path, &result));
+    ASSERT_EQ(td.path, result);
+  }
+
+  {
+    std::string path = std::string(td.path) + "/..";
+    std::string result;
+    ASSERT_TRUE(android::base::Realpath(path, &result));
+    ASSERT_EQ(dir_name, result);
+  }
+
+  {
+    errno = 0;
+    std::string path = std::string(td.path) + "/foo.noent";
+    std::string result = "wrong";
+    ASSERT_TRUE(!android::base::Realpath(path, &result));
+    ASSERT_TRUE(result.empty());
+    ASSERT_EQ(ENOENT, errno);
+  }
+#endif
+}
+
 TEST(file, GetExecutableDirectory) {
   std::string path = android::base::GetExecutableDirectory();
   ASSERT_NE("", path);
diff --git a/base/include/android-base/file.h b/base/include/android-base/file.h
index 33d1ab3..651f529 100644
--- a/base/include/android-base/file.h
+++ b/base/include/android-base/file.h
@@ -47,6 +47,7 @@
 bool RemoveFileIfExists(const std::string& path, std::string* err = nullptr);
 
 #if !defined(_WIN32)
+bool Realpath(const std::string& path, std::string* result);
 bool Readlink(const std::string& path, std::string* result);
 #endif
 
diff --git a/debuggerd/Android.bp b/debuggerd/Android.bp
index b385ea5..2d6c7f5 100644
--- a/debuggerd/Android.bp
+++ b/debuggerd/Android.bp
@@ -1,5 +1,6 @@
 cc_defaults {
     name: "debuggerd_defaults",
+    defaults: ["linux_bionic_supported"],
     cflags: [
         "-Wall",
         "-Wextra",
diff --git a/debuggerd/crash_dump.cpp b/debuggerd/crash_dump.cpp
index 38b711f..88f390b 100644
--- a/debuggerd/crash_dump.cpp
+++ b/debuggerd/crash_dump.cpp
@@ -27,6 +27,7 @@
 #include <unistd.h>
 
 #include <limits>
+#include <map>
 #include <memory>
 #include <set>
 #include <vector>
@@ -36,6 +37,7 @@
 #include <android-base/parseint.h>
 #include <android-base/properties.h>
 #include <android-base/stringprintf.h>
+#include <android-base/strings.h>
 #include <android-base/unique_fd.h>
 #include <cutils/sockets.h>
 #include <log/log.h>
@@ -52,7 +54,21 @@
 #include "debuggerd/util.h"
 
 using android::base::unique_fd;
+using android::base::ReadFileToString;
 using android::base::StringPrintf;
+using android::base::Trim;
+
+static std::string get_process_name(pid_t pid) {
+  std::string result = "<unknown>";
+  ReadFileToString(StringPrintf("/proc/%d/cmdline", pid), &result);
+  return result;
+}
+
+static std::string get_thread_name(pid_t tid) {
+  std::string result = "<unknown>";
+  ReadFileToString(StringPrintf("/proc/%d/comm", tid), &result);
+  return Trim(result);
+}
 
 static bool pid_contains_tid(int pid_proc_fd, pid_t tid) {
   struct stat st;
@@ -253,7 +269,7 @@
   }
 
   // Seize the siblings.
-  std::set<pid_t> attached_siblings;
+  std::map<pid_t, std::string> threads;
   {
     std::set<pid_t> siblings;
     if (!android::procinfo::GetProcessTids(target, &siblings)) {
@@ -269,12 +285,12 @@
       if (!ptrace_seize_thread(target_proc_fd, sibling_tid, &attach_error)) {
         LOG(WARNING) << attach_error;
       } else {
-        attached_siblings.insert(sibling_tid);
+        threads.emplace(sibling_tid, get_thread_name(sibling_tid));
       }
     }
   }
 
-  // Collect the backtrace map and open files, while the process still has PR_GET_DUMPABLE=1
+  // Collect the backtrace map, open files, and process/thread names, while we still have caps.
   std::unique_ptr<BacktraceMap> backtrace_map(BacktraceMap::Create(main_tid));
   if (!backtrace_map) {
     LOG(FATAL) << "failed to create backtrace map";
@@ -284,6 +300,9 @@
   OpenFilesList open_files;
   populate_open_files_list(target, &open_files);
 
+  std::string process_name = get_process_name(main_tid);
+  threads.emplace(main_tid, get_thread_name(main_tid));
+
   // Drop our capabilities now that we've attached to the threads we care about.
   drop_capabilities();
 
@@ -341,10 +360,10 @@
 
   std::string amfd_data;
   if (backtrace) {
-    dump_backtrace(output_fd.get(), backtrace_map.get(), target, main_tid, attached_siblings, 0);
+    dump_backtrace(output_fd.get(), backtrace_map.get(), target, main_tid, process_name, threads, 0);
   } else {
     engrave_tombstone(output_fd.get(), backtrace_map.get(), &open_files, target, main_tid,
-                      &attached_siblings, abort_address, fatal_signal ? &amfd_data : nullptr);
+                      process_name, threads, abort_address, fatal_signal ? &amfd_data : nullptr);
   }
 
   // We don't actually need to PTRACE_DETACH, as long as our tracees aren't in
diff --git a/debuggerd/libdebuggerd/backtrace.cpp b/debuggerd/libdebuggerd/backtrace.cpp
index df49aef..334d97f 100644
--- a/debuggerd/libdebuggerd/backtrace.cpp
+++ b/debuggerd/libdebuggerd/backtrace.cpp
@@ -38,18 +38,7 @@
 
 #include "utility.h"
 
-static void dump_process_header(log_t* log, pid_t pid) {
-  char path[PATH_MAX];
-  char procnamebuf[1024];
-  char* procname = NULL;
-  FILE* fp;
-
-  snprintf(path, sizeof(path), "/proc/%d/cmdline", pid);
-  if ((fp = fopen(path, "r"))) {
-    procname = fgets(procnamebuf, sizeof(procnamebuf), fp);
-    fclose(fp);
-  }
-
+static void dump_process_header(log_t* log, pid_t pid, const char* process_name) {
   time_t t = time(NULL);
   struct tm tm;
   localtime_r(&t, &tm);
@@ -57,8 +46,8 @@
   strftime(timestr, sizeof(timestr), "%F %T", &tm);
   _LOG(log, logtype::BACKTRACE, "\n\n----- pid %d at %s -----\n", pid, timestr);
 
-  if (procname) {
-    _LOG(log, logtype::BACKTRACE, "Cmd line: %s\n", procname);
+  if (process_name) {
+    _LOG(log, logtype::BACKTRACE, "Cmd line: %s\n", process_name);
   }
   _LOG(log, logtype::BACKTRACE, "ABI: '%s'\n", ABI_STRING);
 }
@@ -67,28 +56,13 @@
   _LOG(log, logtype::BACKTRACE, "\n----- end %d -----\n", pid);
 }
 
-static void log_thread_name(log_t* log, pid_t tid) {
-  FILE* fp;
-  char buf[1024];
-  char path[PATH_MAX];
-  char* threadname = NULL;
-
-  snprintf(path, sizeof(path), "/proc/%d/comm", tid);
-  if ((fp = fopen(path, "r"))) {
-    threadname = fgets(buf, sizeof(buf), fp);
-    fclose(fp);
-    if (threadname) {
-      size_t len = strlen(threadname);
-      if (len && threadname[len - 1] == '\n') {
-          threadname[len - 1] = '\0';
-      }
-    }
-  }
-  _LOG(log, logtype::BACKTRACE, "\n\"%s\" sysTid=%d\n", threadname ? threadname : "<unknown>", tid);
+static void log_thread_name(log_t* log, pid_t tid, const char* thread_name) {
+  _LOG(log, logtype::BACKTRACE, "\n\"%s\" sysTid=%d\n", thread_name, tid);
 }
 
-static void dump_thread(log_t* log, BacktraceMap* map, pid_t pid, pid_t tid) {
-  log_thread_name(log, tid);
+static void dump_thread(log_t* log, BacktraceMap* map, pid_t pid, pid_t tid,
+                        const std::string& thread_name) {
+  log_thread_name(log, tid, thread_name.c_str());
 
   std::unique_ptr<Backtrace> backtrace(Backtrace::Create(pid, tid, map));
   if (backtrace->Unwind(0)) {
@@ -99,17 +73,21 @@
   }
 }
 
-void dump_backtrace(int fd, BacktraceMap* map, pid_t pid, pid_t tid,
-                    const std::set<pid_t>& siblings, std::string* amfd_data) {
+void dump_backtrace(int fd, BacktraceMap* map, pid_t pid, pid_t tid, const std::string& process_name,
+                    const std::map<pid_t, std::string>& threads, std::string* amfd_data) {
   log_t log;
   log.tfd = fd;
   log.amfd_data = amfd_data;
 
-  dump_process_header(&log, pid);
-  dump_thread(&log, map, pid, tid);
+  dump_process_header(&log, pid, process_name.c_str());
+  dump_thread(&log, map, pid, tid, threads.find(tid)->second.c_str());
 
-  for (pid_t sibling : siblings) {
-    dump_thread(&log, map, pid, sibling);
+  for (const auto& it : threads) {
+    pid_t thread_tid = it.first;
+    const std::string& thread_name = it.second;
+    if (thread_tid != tid) {
+      dump_thread(&log, map, pid, thread_tid, thread_name.c_str());
+    }
   }
 
   dump_process_footer(&log, pid);
@@ -123,7 +101,9 @@
   log.tfd = output_fd;
   log.amfd_data = nullptr;
 
-  log_thread_name(&log, tid);
+  char thread_name[16];
+  read_with_default("/proc/self/comm", thread_name, sizeof(thread_name), "<unknown>");
+  log_thread_name(&log, tid, thread_name);
 
   std::unique_ptr<Backtrace> backtrace(Backtrace::Create(pid, tid));
   if (backtrace->Unwind(0, ucontext)) {
@@ -139,7 +119,9 @@
   log.tfd = output_fd;
   log.amfd_data = nullptr;
 
-  dump_process_header(&log, getpid());
+  char process_name[128];
+  read_with_default("/proc/self/cmdline", process_name, sizeof(process_name), "<unknown>");
+  dump_process_header(&log, getpid(), process_name);
 }
 
 void dump_backtrace_footer(int output_fd) {
diff --git a/debuggerd/libdebuggerd/include/backtrace.h b/debuggerd/libdebuggerd/include/backtrace.h
index 5bfdac8..fe738f1 100644
--- a/debuggerd/libdebuggerd/include/backtrace.h
+++ b/debuggerd/libdebuggerd/include/backtrace.h
@@ -20,7 +20,7 @@
 #include <sys/types.h>
 #include <sys/ucontext.h>
 
-#include <set>
+#include <map>
 #include <string>
 
 #include "utility.h"
@@ -30,8 +30,8 @@
 
 // Dumps a backtrace using a format similar to what Dalvik uses so that the result
 // can be intermixed in a bug report.
-void dump_backtrace(int fd, BacktraceMap* map, pid_t pid, pid_t tid,
-                    const std::set<pid_t>& siblings, std::string* amfd_data);
+void dump_backtrace(int fd, BacktraceMap* map, pid_t pid, pid_t tid, const std::string& process_name,
+                    const std::map<pid_t, std::string>& threads, std::string* amfd_data);
 
 /* Dumps the backtrace in the backtrace data structure to the log. */
 void dump_backtrace_to_log(Backtrace* backtrace, log_t* log, const char* prefix);
diff --git a/debuggerd/libdebuggerd/include/tombstone.h b/debuggerd/libdebuggerd/include/tombstone.h
index d2a4a4b..79743b6 100644
--- a/debuggerd/libdebuggerd/include/tombstone.h
+++ b/debuggerd/libdebuggerd/include/tombstone.h
@@ -20,7 +20,8 @@
 #include <stdbool.h>
 #include <stddef.h>
 #include <sys/types.h>
-#include <set>
+
+#include <map>
 #include <string>
 
 #include "open_files_list.h"
@@ -34,9 +35,9 @@
 int open_tombstone(std::string* path);
 
 /* Creates a tombstone file and writes the crash dump to it. */
-void engrave_tombstone(int tombstone_fd, BacktraceMap* map,
-                       const OpenFilesList* open_files, pid_t pid, pid_t tid,
-                       const std::set<pid_t>* siblings, uintptr_t abort_msg_address,
+void engrave_tombstone(int tombstone_fd, BacktraceMap* map, const OpenFilesList* open_files,
+                       pid_t pid, pid_t tid, const std::string& process_name,
+                       const std::map<pid_t, std::string>& threads, uintptr_t abort_msg_address,
                        std::string* amfd_data);
 
 void engrave_tombstone_ucontext(int tombstone_fd, uintptr_t abort_msg_address, siginfo_t* siginfo,
diff --git a/debuggerd/libdebuggerd/include/utility.h b/debuggerd/libdebuggerd/include/utility.h
index bbc4546..e5e5106 100644
--- a/debuggerd/libdebuggerd/include/utility.h
+++ b/debuggerd/libdebuggerd/include/utility.h
@@ -83,4 +83,6 @@
 
 void dump_memory(log_t* log, Backtrace* backtrace, uintptr_t addr, const char* fmt, ...);
 
+void read_with_default(const char* path, char* buf, size_t len, const char* default_value);
+
 #endif // _DEBUGGERD_UTILITY_H
diff --git a/debuggerd/libdebuggerd/tombstone.cpp b/debuggerd/libdebuggerd/tombstone.cpp
index c05ccc3..c23da44 100644
--- a/debuggerd/libdebuggerd/tombstone.cpp
+++ b/debuggerd/libdebuggerd/tombstone.cpp
@@ -32,8 +32,10 @@
 #include <memory>
 #include <string>
 
-#include <android/log.h>
+#include <android-base/file.h>
 #include <android-base/stringprintf.h>
+#include <android-base/unique_fd.h>
+#include <android/log.h>
 #include <backtrace/Backtrace.h>
 #include <backtrace/BacktraceMap.h>
 #include <cutils/properties.h>
@@ -247,41 +249,16 @@
   dump_signal_info(log, &si);
 }
 
-static void dump_thread_info(log_t* log, pid_t pid, pid_t tid) {
-  char path[64];
-  char threadnamebuf[1024];
-  char* threadname = nullptr;
-  FILE *fp;
-
-  snprintf(path, sizeof(path), "/proc/%d/comm", tid);
-  if ((fp = fopen(path, "r"))) {
-    threadname = fgets(threadnamebuf, sizeof(threadnamebuf), fp);
-    fclose(fp);
-    if (threadname) {
-      size_t len = strlen(threadname);
-      if (len && threadname[len - 1] == '\n') {
-        threadname[len - 1] = '\0';
-      }
-    }
-  }
+static void dump_thread_info(log_t* log, pid_t pid, pid_t tid, const char* process_name,
+                             const char* thread_name) {
   // Blacklist logd, logd.reader, logd.writer, logd.auditd, logd.control ...
-  static const char logd[] = "logd";
-  if (threadname != nullptr && !strncmp(threadname, logd, sizeof(logd) - 1)
-      && (!threadname[sizeof(logd) - 1] || (threadname[sizeof(logd) - 1] == '.'))) {
+  // TODO: Why is this controlled by thread name?
+  if (strcmp(thread_name, "logd") == 0 || strncmp(thread_name, "logd.", 4) == 0) {
     log->should_retrieve_logcat = false;
   }
 
-  char procnamebuf[1024];
-  char* procname = nullptr;
-
-  snprintf(path, sizeof(path), "/proc/%d/cmdline", pid);
-  if ((fp = fopen(path, "r"))) {
-    procname = fgets(procnamebuf, sizeof(procnamebuf), fp);
-    fclose(fp);
-  }
-
-  _LOG(log, logtype::HEADER, "pid: %d, tid: %d, name: %s  >>> %s <<<\n", pid, tid,
-       threadname ? threadname : "UNKNOWN", procname ? procname : "UNKNOWN");
+  _LOG(log, logtype::HEADER, "pid: %d, tid: %d, name: %s  >>> %s <<<\n", pid, tid, thread_name,
+       process_name);
 }
 
 static void dump_stack_segment(
@@ -493,13 +470,14 @@
   }
 }
 
-static void dump_thread(log_t* log, pid_t pid, pid_t tid, BacktraceMap* map,
+static void dump_thread(log_t* log, pid_t pid, pid_t tid, const std::string& process_name,
+                        const std::string& thread_name, BacktraceMap* map,
                         uintptr_t abort_msg_address, bool primary_thread) {
   log->current_tid = tid;
   if (!primary_thread) {
     _LOG(log, logtype::THREAD, "--- --- --- --- --- --- --- --- --- --- --- --- --- --- --- ---\n");
   }
-  dump_thread_info(log, pid, tid);
+  dump_thread_info(log, pid, tid, process_name.c_str(), thread_name.c_str());
   dump_signal_info(log, tid);
 
   std::unique_ptr<Backtrace> backtrace(Backtrace::Create(pid, tid, map));
@@ -654,9 +632,9 @@
 }
 
 // Dumps all information about the specified pid to the tombstone.
-static void dump_crash(log_t* log, BacktraceMap* map,
-                       const OpenFilesList* open_files, pid_t pid, pid_t tid,
-                       const std::set<pid_t>* siblings, uintptr_t abort_msg_address) {
+static void dump_crash(log_t* log, BacktraceMap* map, const OpenFilesList* open_files, pid_t pid,
+                       pid_t tid, const std::string& process_name,
+                       const std::map<pid_t, std::string>& threads, uintptr_t abort_msg_address) {
   // don't copy log messages to tombstone unless this is a dev device
   char value[PROPERTY_VALUE_MAX];
   property_get("ro.debuggable", value, "0");
@@ -665,14 +643,17 @@
   _LOG(log, logtype::HEADER,
        "*** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***\n");
   dump_header_info(log);
-  dump_thread(log, pid, tid, map, abort_msg_address, true);
+  dump_thread(log, pid, tid, process_name, threads.find(tid)->second, map, abort_msg_address, true);
   if (want_logs) {
     dump_logs(log, pid, 5);
   }
 
-  if (siblings && !siblings->empty()) {
-    for (pid_t sibling : *siblings) {
-      dump_thread(log, pid, sibling, map, 0, false);
+  for (const auto& it : threads) {
+    pid_t thread_tid = it.first;
+    const std::string& thread_name = it.second;
+
+    if (thread_tid != tid) {
+      dump_thread(log, pid, thread_tid, process_name, thread_name, map, 0, false);
     }
   }
 
@@ -739,16 +720,16 @@
   return fd;
 }
 
-void engrave_tombstone(int tombstone_fd, BacktraceMap* map,
-                       const OpenFilesList* open_files, pid_t pid, pid_t tid,
-                       const std::set<pid_t>* siblings, uintptr_t abort_msg_address,
+void engrave_tombstone(int tombstone_fd, BacktraceMap* map, const OpenFilesList* open_files,
+                       pid_t pid, pid_t tid, const std::string& process_name,
+                       const std::map<pid_t, std::string>& threads, uintptr_t abort_msg_address,
                        std::string* amfd_data) {
   log_t log;
   log.current_tid = tid;
   log.crashed_tid = tid;
   log.tfd = tombstone_fd;
   log.amfd_data = amfd_data;
-  dump_crash(&log, map, open_files, pid, tid, siblings, abort_msg_address);
+  dump_crash(&log, map, open_files, pid, tid, process_name, threads, abort_msg_address);
 }
 
 void engrave_tombstone_ucontext(int tombstone_fd, uintptr_t abort_msg_address, siginfo_t* siginfo,
@@ -762,7 +743,13 @@
   log.tfd = tombstone_fd;
   log.amfd_data = nullptr;
 
-  dump_thread_info(&log, pid, tid);
+  char thread_name[16];
+  char process_name[128];
+
+  read_with_default("/proc/self/comm", thread_name, sizeof(thread_name), "<unknown>");
+  read_with_default("/proc/self/cmdline", process_name, sizeof(process_name), "<unknown>");
+
+  dump_thread_info(&log, pid, tid, thread_name, process_name);
   dump_signal_info(&log, siginfo);
 
   std::unique_ptr<Backtrace> backtrace(Backtrace::Create(pid, tid));
diff --git a/debuggerd/libdebuggerd/utility.cpp b/debuggerd/libdebuggerd/utility.cpp
index 744cd72..22fde5e 100644
--- a/debuggerd/libdebuggerd/utility.cpp
+++ b/debuggerd/libdebuggerd/utility.cpp
@@ -28,6 +28,7 @@
 #include <string>
 
 #include <android-base/stringprintf.h>
+#include <android-base/unique_fd.h>
 #include <backtrace/Backtrace.h>
 #include <log/log.h>
 
@@ -202,3 +203,20 @@
     _LOG(log, logtype::MEMORY, "%s  %s\n", logline.c_str(), ascii.c_str());
   }
 }
+
+void read_with_default(const char* path, char* buf, size_t len, const char* default_value) {
+  android::base::unique_fd fd(open(path, O_RDONLY));
+  if (fd != -1) {
+    int rc = TEMP_FAILURE_RETRY(read(fd.get(), buf, len - 1));
+    if (rc != -1) {
+      buf[rc] = '\0';
+
+      // Trim trailing newlines.
+      if (rc > 0 && buf[rc - 1] == '\n') {
+        buf[rc - 1] = '\0';
+      }
+      return;
+    }
+  }
+  strcpy(buf, default_value);
+}
diff --git a/fs_mgr/fs_mgr_fstab.cpp b/fs_mgr/fs_mgr_fstab.cpp
index 6646a3c..67cc5be 100644
--- a/fs_mgr/fs_mgr_fstab.cpp
+++ b/fs_mgr/fs_mgr_fstab.cpp
@@ -650,7 +650,7 @@
 {
     std::string fstab_buf = read_fstab_from_dt();
     if (fstab_buf.empty()) {
-        LERROR << __FUNCTION__ << "(): failed to read fstab from dt";
+        LINFO << __FUNCTION__ << "(): failed to read fstab from dt";
         return nullptr;
     }
 
diff --git a/include/private/android_filesystem_config.h b/include/private/android_filesystem_config.h
index 8e2bc1c..48a0e61 100644
--- a/include/private/android_filesystem_config.h
+++ b/include/private/android_filesystem_config.h
@@ -123,11 +123,12 @@
 #define AID_DNS_TETHER    1052  /* DNS resolution daemon (tether: dnsmasq) */
 #define AID_WEBVIEW_ZYGOTE 1053 /* WebView zygote process */
 #define AID_VEHICLE_NETWORK 1054 /* Vehicle network service */
-#define AID_MEDIA_AUDIO   1055 /* GID for audio files on internal media storage */
-#define AID_MEDIA_VIDEO   1056 /* GID for video files on internal media storage */
-#define AID_MEDIA_IMAGE   1057 /* GID for image files on internal media storage */
+#define AID_MEDIA_AUDIO   1055  /* GID for audio files on internal media storage */
+#define AID_MEDIA_VIDEO   1056  /* GID for video files on internal media storage */
+#define AID_MEDIA_IMAGE   1057  /* GID for image files on internal media storage */
 #define AID_TOMBSTONED    1058  /* tombstoned user */
-#define AID_MEDIA_OBB     1059 /* GID for OBB files on internal media storage */
+#define AID_MEDIA_OBB     1059  /* GID for OBB files on internal media storage */
+#define AID_ESE           1060  /* embedded secure element (eSE) subsystem */
 /* Changes to this file must be made in AOSP, *not* in internal branches. */
 
 #define AID_SHELL         2000  /* adb and debug shell user */
diff --git a/libbacktrace/Android.bp b/libbacktrace/Android.bp
index 5b31ecb..0e7c6f3 100644
--- a/libbacktrace/Android.bp
+++ b/libbacktrace/Android.bp
@@ -80,6 +80,18 @@
             static_libs: ["libcutils"],
             host_ldlibs: ["-lrt"],
         },
+        linux_bionic: {
+            enabled: true,
+            srcs: libbacktrace_sources,
+
+            shared_libs: [
+                "libbase",
+                "liblog",
+                "libunwind",
+            ],
+
+            static_libs: ["libcutils"],
+        },
         android: {
             srcs: libbacktrace_sources,
 
diff --git a/libcutils/Android.bp b/libcutils/Android.bp
index cf31195..f668f18 100644
--- a/libcutils/Android.bp
+++ b/libcutils/Android.bp
@@ -41,9 +41,12 @@
     host_supported: true,
     export_include_dirs: ["include"],
     target: {
-       windows: {
-          enabled: true,
-       },
+        linux_bionic: {
+            enabled: true,
+        },
+        windows: {
+            enabled: true,
+        },
     },
 }
 
@@ -68,11 +71,14 @@
         "threads.c",
     ],
 
-
     target: {
         host: {
             srcs: ["dlmalloc_stubs.c"],
         },
+        linux_bionic: {
+            enabled: true,
+            exclude_srcs: ["dlmalloc_stubs.c"],
+        },
         not_windows: {
             srcs: libcutils_nonwindows_sources + [
                 "ashmem-host.c",
diff --git a/liblog/tests/liblog_test.cpp b/liblog/tests/liblog_test.cpp
index 5a52377..e68c8f2 100644
--- a/liblog/tests/liblog_test.cpp
+++ b/liblog/tests/liblog_test.cpp
@@ -1778,7 +1778,14 @@
   // liblog.android_logger_get_ is one of those tests that has no recourse
   // and that would be adversely affected by emptying the log if it was run
   // right after this test.
-  system("stop logd");
+  if (getuid() != AID_ROOT) {
+    fprintf(
+        stderr,
+        "WARNING: test conditions request being run as root and not AID=%d\n",
+        getuid());
+  }
+
+  system((getuid() == AID_ROOT) ? "stop logd" : "su 0 stop logd");
   usleep(1000000);
 
   // A clean stop like we are testing returns -ENOENT, but in the _real_
@@ -1789,20 +1796,20 @@
   int ret = __android_log_btwrite(0, EVENT_TYPE_LONG, &ts, sizeof(ts));
   std::string content = android::base::StringPrintf(
       "__android_log_btwrite(0, EVENT_TYPE_LONG, &ts, sizeof(ts)) = %d %s\n",
-      ret, strerror(-ret));
+      ret, (ret <= 0) ? strerror(-ret) : "(content sent)");
   EXPECT_TRUE(
       IsOk((ret == -ENOENT) || (ret == -ENOTCONN) || (ret == -ECONNREFUSED),
            content));
   ret = __android_log_btwrite(0, EVENT_TYPE_LONG, &ts, sizeof(ts));
   content = android::base::StringPrintf(
       "__android_log_btwrite(0, EVENT_TYPE_LONG, &ts, sizeof(ts)) = %d %s\n",
-      ret, strerror(-ret));
+      ret, (ret <= 0) ? strerror(-ret) : "(content sent)");
   EXPECT_TRUE(
       IsOk((ret == -ENOENT) || (ret == -ENOTCONN) || (ret == -ECONNREFUSED),
            content));
   EXPECT_EQ(0, count_matching_ts(ts));
 
-  system("start logd");
+  system((getuid() == AID_ROOT) ? "start logd" : "su 0 start logd");
   usleep(1000000);
 
   EXPECT_EQ(0, count_matching_ts(ts));
@@ -1831,14 +1838,24 @@
   char persist[PROP_VALUE_MAX];
   char readonly[PROP_VALUE_MAX];
 
+  // First part of this test requires the test itself to have the appropriate
+  // permissions. If we do not have them, we can not override them, so we
+  // bail rather than give a failing grade.
   property_get(persist_key, persist, "");
+  fprintf(stderr, "INFO: getprop %s -> %s\n", persist_key, persist);
   property_get(readonly_key, readonly, nothing_val);
+  fprintf(stderr, "INFO: getprop %s -> %s\n", readonly_key, readonly);
 
   if (!strcmp(readonly, nothing_val)) {
     EXPECT_FALSE(__android_log_security());
-    fprintf(stderr, "Warning, setting ro.device_owner to a domain\n");
-    property_set(readonly_key, "com.google.android.SecOps.DeviceOwner");
+    fprintf(stderr, "WARNING: setting ro.device_owner to a domain\n");
+    static const char domain[] = "com.google.android.SecOps.DeviceOwner";
+    property_set(readonly_key, domain);
+    usleep(20000);  // property system does not guarantee performance, rest ...
+    property_get(readonly_key, readonly, nothing_val);
+    EXPECT_STREQ(readonly, domain);
   } else if (!strcasecmp(readonly, "false") || !readonly[0]) {
+    // not enough permissions to run
     EXPECT_FALSE(__android_log_security());
     return;
   }
diff --git a/libprocinfo/Android.bp b/libprocinfo/Android.bp
index 8e17f1b..c13ffe9 100644
--- a/libprocinfo/Android.bp
+++ b/libprocinfo/Android.bp
@@ -35,6 +35,9 @@
         darwin: {
             enabled: false,
         },
+        linux_bionic: {
+            enabled: true,
+        },
         windows: {
             enabled: false,
         },
diff --git a/libunwindstack/Android.bp b/libunwindstack/Android.bp
index 9bb1304..ece623b 100644
--- a/libunwindstack/Android.bp
+++ b/libunwindstack/Android.bp
@@ -30,6 +30,15 @@
             enabled: false,
         },
     },
+
+    multilib: {
+        lib32: {
+            suffix: "32",
+        },
+        lib64: {
+            suffix: "64",
+        },
+    },
 }
 
 cc_defaults {
@@ -38,8 +47,12 @@
 
     srcs: [
         "ArmExidx.cpp",
-        "Memory.cpp",
+        "Elf.cpp",
+        "ElfInterface.cpp",
+        "ElfInterfaceArm.cpp",
         "Log.cpp",
+        "Regs.cpp",
+        "Memory.cpp",
     ],
 
     shared_libs: [
@@ -74,6 +87,9 @@
     srcs: [
         "tests/ArmExidxDecodeTest.cpp",
         "tests/ArmExidxExtractTest.cpp",
+        "tests/ElfInterfaceArmTest.cpp",
+        "tests/ElfInterfaceTest.cpp",
+        "tests/ElfTest.cpp",
         "tests/LogFake.cpp",
         "tests/MemoryFake.cpp",
         "tests/MemoryFileTest.cpp",
@@ -93,15 +109,6 @@
         "liblog",
     ],
 
-    multilib: {
-        lib32: {
-            suffix: "32",
-        },
-        lib64: {
-            suffix: "64",
-        },
-    },
-
     target: {
         linux: {
             host_ldlibs: [
@@ -130,3 +137,31 @@
         "libunwindstack_debug",
     ],
 }
+
+//-------------------------------------------------------------------------
+// Utility Executables
+//-------------------------------------------------------------------------
+cc_defaults {
+    name: "libunwindstack_executables",
+    defaults: ["libunwindstack_flags"],
+
+    shared_libs: [
+        "libunwindstack",
+        "libbase",
+    ],
+
+    static_libs: [
+        "liblog",
+    ],
+
+    compile_multilib: "both",
+}
+
+cc_binary {
+    name: "unwind_info",
+    defaults: ["libunwindstack_executables"],
+
+    srcs: [
+        "unwind_info.cpp",
+    ],
+}
diff --git a/libunwindstack/ArmExidx.cpp b/libunwindstack/ArmExidx.cpp
index 3b78918..12adf57 100644
--- a/libunwindstack/ArmExidx.cpp
+++ b/libunwindstack/ArmExidx.cpp
@@ -25,6 +25,8 @@
 #include "ArmExidx.h"
 #include "Log.h"
 #include "Machine.h"
+#include "Memory.h"
+#include "Regs.h"
 
 void ArmExidx::LogRawData() {
   std::string log_str("Raw Data:");
@@ -216,10 +218,16 @@
       cfa_ += 4;
     }
   }
+
   // If the sp register is modified, change the cfa value.
   if (registers & (1 << ARM_REG_SP)) {
     cfa_ = (*regs_)[ARM_REG_SP];
   }
+
+  // Indicate if the pc register was set.
+  if (registers & (1 << ARM_REG_PC)) {
+    pc_set_ = true;
+  }
   return true;
 }
 
@@ -296,9 +304,6 @@
       return false;
     }
   }
-  if (!(*regs_)[ARM_REG_PC]) {
-    (*regs_)[ARM_REG_PC] = (*regs_)[ARM_REG_LR];
-  }
   status_ = ARM_STATUS_FINISH;
   return false;
 }
@@ -675,6 +680,7 @@
 }
 
 bool ArmExidx::Eval() {
+  pc_set_ = false;
   while (Decode());
   return status_ == ARM_STATUS_FINISH;
 }
diff --git a/libunwindstack/ArmExidx.h b/libunwindstack/ArmExidx.h
index a92caef..8c7f15a 100644
--- a/libunwindstack/ArmExidx.h
+++ b/libunwindstack/ArmExidx.h
@@ -21,8 +21,9 @@
 
 #include <deque>
 
-#include "Memory.h"
-#include "Regs.h"
+// Forward declarations.
+class Memory;
+class RegsArm;
 
 enum ArmStatus : size_t {
   ARM_STATUS_NONE = 0,
@@ -43,7 +44,7 @@
 
 class ArmExidx {
  public:
-  ArmExidx(Regs32* regs, Memory* elf_memory, Memory* process_memory)
+  ArmExidx(RegsArm* regs, Memory* elf_memory, Memory* process_memory)
       : regs_(regs), elf_memory_(elf_memory), process_memory_(process_memory) {}
   virtual ~ArmExidx() {}
 
@@ -59,11 +60,14 @@
 
   ArmStatus status() { return status_; }
 
-  Regs32* regs() { return regs_; }
+  RegsArm* regs() { return regs_; }
 
   uint32_t cfa() { return cfa_; }
   void set_cfa(uint32_t cfa) { cfa_ = cfa; }
 
+  bool pc_set() { return pc_set_; }
+  void set_pc_set(bool pc_set) { pc_set_ = pc_set; }
+
   void set_log(bool log) { log_ = log; }
   void set_log_skip_execution(bool skip_execution) { log_skip_execution_ = skip_execution; }
   void set_log_indent(uint8_t indent) { log_indent_ = indent; }
@@ -87,7 +91,7 @@
   bool DecodePrefix_11_010(uint8_t byte);
   bool DecodePrefix_11(uint8_t byte);
 
-  Regs32* regs_ = nullptr;
+  RegsArm* regs_ = nullptr;
   uint32_t cfa_ = 0;
   std::deque<uint8_t> data_;
   ArmStatus status_ = ARM_STATUS_NONE;
@@ -98,6 +102,7 @@
   bool log_ = false;
   uint8_t log_indent_ = 0;
   bool log_skip_execution_ = false;
+  bool pc_set_ = false;
 };
 
 #endif  // _LIBUNWINDSTACK_ARM_EXIDX_H
diff --git a/libunwindstack/Elf.cpp b/libunwindstack/Elf.cpp
new file mode 100644
index 0000000..272b5f0
--- /dev/null
+++ b/libunwindstack/Elf.cpp
@@ -0,0 +1,113 @@
+/*
+ * Copyright (C) 2016 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 <elf.h>
+#include <string.h>
+
+#include <memory>
+#include <string>
+
+#define LOG_TAG "unwind"
+#include <log/log.h>
+
+#include "Elf.h"
+#include "ElfInterface.h"
+#include "ElfInterfaceArm.h"
+#include "Machine.h"
+#include "Memory.h"
+#include "Regs.h"
+
+bool Elf::Init() {
+  if (!memory_) {
+    return false;
+  }
+
+  interface_.reset(CreateInterfaceFromMemory(memory_.get()));
+  if (!interface_) {
+    return false;
+  }
+
+  valid_ = interface_->Init();
+  if (valid_) {
+    interface_->InitHeaders();
+  } else {
+    interface_.reset(nullptr);
+  }
+  return valid_;
+}
+
+bool Elf::IsValidElf(Memory* memory) {
+  if (memory == nullptr) {
+    return false;
+  }
+
+  // Verify that this is a valid elf file.
+  uint8_t e_ident[SELFMAG + 1];
+  if (!memory->Read(0, e_ident, SELFMAG)) {
+    return false;
+  }
+
+  if (memcmp(e_ident, ELFMAG, SELFMAG) != 0) {
+    return false;
+  }
+  return true;
+}
+
+ElfInterface* Elf::CreateInterfaceFromMemory(Memory* memory) {
+  if (!IsValidElf(memory)) {
+    return nullptr;
+  }
+
+  std::unique_ptr<ElfInterface> interface;
+  if (!memory->Read(EI_CLASS, &class_type_, 1)) {
+    return nullptr;
+  }
+  if (class_type_ == ELFCLASS32) {
+    Elf32_Half e_machine;
+    if (!memory->Read(EI_NIDENT + sizeof(Elf32_Half), &e_machine, sizeof(e_machine))) {
+      return nullptr;
+    }
+
+    if (e_machine != EM_ARM && e_machine != EM_386) {
+      // Unsupported.
+      ALOGI("32 bit elf that is neither arm nor x86: e_machine = %d\n", e_machine);
+      return nullptr;
+    }
+
+    machine_type_ = e_machine;
+    if (e_machine == EM_ARM) {
+      interface.reset(new ElfInterfaceArm(memory));
+    } else {
+      interface.reset(new ElfInterface32(memory));
+    }
+  } else if (class_type_ == ELFCLASS64) {
+    Elf64_Half e_machine;
+    if (!memory->Read(EI_NIDENT + sizeof(Elf64_Half), &e_machine, sizeof(e_machine))) {
+      return nullptr;
+    }
+
+    if (e_machine != EM_AARCH64 && e_machine != EM_X86_64) {
+      // Unsupported.
+      ALOGI("64 bit elf that is neither aarch64 nor x86_64: e_machine = %d\n", e_machine);
+      return nullptr;
+    }
+
+    machine_type_ = e_machine;
+    interface.reset(new ElfInterface64(memory));
+  }
+
+  return interface.release();
+}
diff --git a/libunwindstack/Elf.h b/libunwindstack/Elf.h
new file mode 100644
index 0000000..7bf45b8
--- /dev/null
+++ b/libunwindstack/Elf.h
@@ -0,0 +1,78 @@
+/*
+ * Copyright (C) 2016 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 _LIBUNWINDSTACK_ELF_H
+#define _LIBUNWINDSTACK_ELF_H
+
+#include <stddef.h>
+
+#include <memory>
+#include <string>
+
+#include "ElfInterface.h"
+#include "Memory.h"
+
+#if !defined(EM_AARCH64)
+#define EM_AARCH64 183
+#endif
+
+// Forward declaration.
+class Regs;
+
+class Elf {
+ public:
+  Elf(Memory* memory) : memory_(memory) {}
+  virtual ~Elf() = default;
+
+  bool Init();
+
+  void InitGnuDebugdata();
+
+  bool GetSoname(std::string* name) {
+    return valid_ && interface_->GetSoname(name);
+  }
+
+  bool GetFunctionName(uint64_t, std::string*, uint64_t*) {
+    return false;
+  }
+
+  bool Step(uint64_t rel_pc, Regs* regs, Memory* process_memory) {
+    return valid_ && interface_->Step(rel_pc, regs, process_memory);
+  }
+
+  ElfInterface* CreateInterfaceFromMemory(Memory* memory);
+
+  bool valid() { return valid_; }
+
+  uint32_t machine_type() { return machine_type_; }
+
+  uint8_t class_type() { return class_type_; }
+
+  Memory* memory() { return memory_.get(); }
+
+  ElfInterface* interface() { return interface_.get(); }
+
+  static bool IsValidElf(Memory* memory);
+
+ protected:
+  bool valid_ = false;
+  std::unique_ptr<ElfInterface> interface_;
+  std::unique_ptr<Memory> memory_;
+  uint32_t machine_type_;
+  uint8_t class_type_;
+};
+
+#endif  // _LIBUNWINDSTACK_ELF_H
diff --git a/libunwindstack/ElfInterface.cpp b/libunwindstack/ElfInterface.cpp
new file mode 100644
index 0000000..d59e9d8
--- /dev/null
+++ b/libunwindstack/ElfInterface.cpp
@@ -0,0 +1,223 @@
+/*
+ * Copyright (C) 2017 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 <elf.h>
+#include <stdint.h>
+
+#include <memory>
+#include <string>
+
+#include "ElfInterface.h"
+#include "Memory.h"
+#include "Regs.h"
+
+template <typename EhdrType, typename PhdrType, typename ShdrType>
+bool ElfInterface::ReadAllHeaders() {
+  EhdrType ehdr;
+  if (!memory_->Read(0, &ehdr, sizeof(ehdr))) {
+    return false;
+  }
+
+  if (!ReadProgramHeaders<EhdrType, PhdrType>(ehdr)) {
+    return false;
+  }
+  return ReadSectionHeaders<EhdrType, ShdrType>(ehdr);
+}
+
+template <typename EhdrType, typename PhdrType>
+bool ElfInterface::ReadProgramHeaders(const EhdrType& ehdr) {
+  uint64_t offset = ehdr.e_phoff;
+  for (size_t i = 0; i < ehdr.e_phnum; i++, offset += ehdr.e_phentsize) {
+    PhdrType phdr;
+    if (!memory_->Read(offset, &phdr, &phdr.p_type, sizeof(phdr.p_type))) {
+      return false;
+    }
+
+    if (HandleType(offset, phdr.p_type)) {
+      continue;
+    }
+
+    switch (phdr.p_type) {
+    case PT_LOAD:
+    {
+      // Get the flags first, if this isn't an executable header, ignore it.
+      if (!memory_->Read(offset, &phdr, &phdr.p_flags, sizeof(phdr.p_flags))) {
+        return false;
+      }
+      if ((phdr.p_flags & PF_X) == 0) {
+        continue;
+      }
+
+      if (!memory_->Read(offset, &phdr, &phdr.p_vaddr, sizeof(phdr.p_vaddr))) {
+        return false;
+      }
+      if (!memory_->Read(offset, &phdr, &phdr.p_offset, sizeof(phdr.p_offset))) {
+        return false;
+      }
+      if (!memory_->Read(offset, &phdr, &phdr.p_memsz, sizeof(phdr.p_memsz))) {
+        return false;
+      }
+      pt_loads_[phdr.p_offset] = LoadInfo{phdr.p_offset, phdr.p_vaddr,
+                                          static_cast<size_t>(phdr.p_memsz)};
+      if (phdr.p_offset == 0) {
+        load_bias_ = phdr.p_vaddr;
+      }
+      break;
+    }
+
+    case PT_GNU_EH_FRAME:
+      if (!memory_->Read(offset, &phdr, &phdr.p_offset, sizeof(phdr.p_offset))) {
+        return false;
+      }
+      eh_frame_offset_ = phdr.p_offset;
+      if (!memory_->Read(offset, &phdr, &phdr.p_memsz, sizeof(phdr.p_memsz))) {
+        return false;
+      }
+      eh_frame_size_ = phdr.p_memsz;
+      break;
+
+    case PT_DYNAMIC:
+      if (!memory_->Read(offset, &phdr, &phdr.p_offset, sizeof(phdr.p_offset))) {
+        return false;
+      }
+      dynamic_offset_ = phdr.p_offset;
+      if (!memory_->Read(offset, &phdr, &phdr.p_memsz, sizeof(phdr.p_memsz))) {
+        return false;
+      }
+      dynamic_size_ = phdr.p_memsz;
+      break;
+    }
+  }
+  return true;
+}
+
+template <typename EhdrType, typename ShdrType>
+bool ElfInterface::ReadSectionHeaders(const EhdrType& ehdr) {
+  uint64_t offset = ehdr.e_shoff;
+  uint64_t sec_offset = 0;
+  uint64_t sec_size = 0;
+
+  // Get the location of the section header names.
+  // If something is malformed in the header table data, we aren't going
+  // to terminate, we'll simply ignore this part.
+  ShdrType shdr;
+  if (ehdr.e_shstrndx < ehdr.e_shnum) {
+    uint64_t sh_offset = offset + ehdr.e_shstrndx * ehdr.e_shentsize;
+    if (memory_->Read(sh_offset, &shdr, &shdr.sh_offset, sizeof(shdr.sh_offset))
+        && memory_->Read(sh_offset, &shdr, &shdr.sh_size, sizeof(shdr.sh_size))) {
+      sec_offset = shdr.sh_offset;
+      sec_size = shdr.sh_size;
+    }
+  }
+
+  // Skip the first header, it's always going to be NULL.
+  for (size_t i = 1; i < ehdr.e_shnum; i++, offset += ehdr.e_shentsize) {
+    if (!memory_->Read(offset, &shdr, &shdr.sh_type, sizeof(shdr.sh_type))) {
+      return false;
+    }
+
+    if (shdr.sh_type == SHT_PROGBITS) {
+      // Look for the .debug_frame and .gnu_debugdata.
+      if (!memory_->Read(offset, &shdr, &shdr.sh_name, sizeof(shdr.sh_name))) {
+        return false;
+      }
+      if (shdr.sh_name < sec_size) {
+        std::string name;
+        if (memory_->ReadString(sec_offset + shdr.sh_name, &name)) {
+          if (name == ".debug_frame") {
+            if (memory_->Read(offset, &shdr, &shdr.sh_offset, sizeof(shdr.sh_offset))
+                && memory_->Read(offset, &shdr, &shdr.sh_size, sizeof(shdr.sh_size))) {
+              debug_frame_offset_ = shdr.sh_offset;
+              debug_frame_size_ = shdr.sh_size;
+            }
+          } else if (name == ".gnu_debugdata") {
+            if (memory_->Read(offset, &shdr, &shdr.sh_offset, sizeof(shdr.sh_offset))
+                && memory_->Read(offset, &shdr, &shdr.sh_size, sizeof(shdr.sh_size))) {
+              gnu_debugdata_offset_ = shdr.sh_offset;
+              gnu_debugdata_size_ = shdr.sh_size;
+            }
+          }
+        }
+      }
+    }
+  }
+  return true;
+}
+
+template <typename DynType>
+bool ElfInterface::GetSonameWithTemplate(std::string* soname) {
+  if (soname_type_ == SONAME_INVALID) {
+    return false;
+  }
+  if (soname_type_ == SONAME_VALID) {
+    *soname = soname_;
+    return true;
+  }
+
+  soname_type_ = SONAME_INVALID;
+
+  uint64_t soname_offset = 0;
+  uint64_t strtab_offset = 0;
+  uint64_t strtab_size = 0;
+
+  // Find the soname location from the dynamic headers section.
+  DynType dyn;
+  uint64_t offset = dynamic_offset_;
+  uint64_t max_offset = offset + dynamic_size_;
+  for (uint64_t offset = dynamic_offset_; offset < max_offset; offset += sizeof(DynType)) {
+    if (!memory_->Read(offset, &dyn, sizeof(dyn))) {
+      return false;
+    }
+
+    if (dyn.d_tag == DT_STRTAB) {
+      strtab_offset = dyn.d_un.d_ptr;
+    } else if (dyn.d_tag == DT_STRSZ) {
+      strtab_size = dyn.d_un.d_val;
+    } else if (dyn.d_tag == DT_SONAME) {
+      soname_offset = dyn.d_un.d_val;
+    } else if (dyn.d_tag == DT_NULL) {
+      break;
+    }
+  }
+
+  soname_offset += strtab_offset;
+  if (soname_offset >= strtab_offset + strtab_size) {
+    return false;
+  }
+  if (!memory_->ReadString(soname_offset, &soname_)) {
+    return false;
+  }
+  soname_type_ = SONAME_VALID;
+  *soname = soname_;
+  return true;
+}
+
+bool ElfInterface::Step(uint64_t, Regs*, Memory*) {
+  return false;
+}
+
+// Instantiate all of the needed template functions.
+template bool ElfInterface::ReadAllHeaders<Elf32_Ehdr, Elf32_Phdr, Elf32_Shdr>();
+template bool ElfInterface::ReadAllHeaders<Elf64_Ehdr, Elf64_Phdr, Elf64_Shdr>();
+
+template bool ElfInterface::ReadProgramHeaders<Elf32_Ehdr, Elf32_Phdr>(const Elf32_Ehdr&);
+template bool ElfInterface::ReadProgramHeaders<Elf64_Ehdr, Elf64_Phdr>(const Elf64_Ehdr&);
+
+template bool ElfInterface::ReadSectionHeaders<Elf32_Ehdr, Elf32_Shdr>(const Elf32_Ehdr&);
+template bool ElfInterface::ReadSectionHeaders<Elf64_Ehdr, Elf64_Shdr>(const Elf64_Ehdr&);
+
+template bool ElfInterface::GetSonameWithTemplate<Elf32_Dyn>(std::string*);
+template bool ElfInterface::GetSonameWithTemplate<Elf64_Dyn>(std::string*);
diff --git a/libunwindstack/ElfInterface.h b/libunwindstack/ElfInterface.h
new file mode 100644
index 0000000..944146c
--- /dev/null
+++ b/libunwindstack/ElfInterface.h
@@ -0,0 +1,152 @@
+/*
+ * Copyright (C) 2016 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 _LIBUNWINDSTACK_ELF_INTERFACE_H
+#define _LIBUNWINDSTACK_ELF_INTERFACE_H
+
+#include <elf.h>
+#include <stdint.h>
+
+#include <memory>
+#include <string>
+#include <unordered_map>
+#include <vector>
+
+// Forward declarations.
+class Memory;
+class Regs;
+
+struct LoadInfo {
+  uint64_t offset;
+  uint64_t table_offset;
+  size_t table_size;
+};
+
+enum : uint8_t {
+  SONAME_UNKNOWN = 0,
+  SONAME_VALID,
+  SONAME_INVALID,
+};
+
+class ElfInterface {
+ public:
+  ElfInterface(Memory* memory) : memory_(memory) {}
+  virtual ~ElfInterface() = default;
+
+  virtual bool Init() = 0;
+
+  virtual void InitHeaders() = 0;
+
+  virtual bool GetSoname(std::string* name) = 0;
+
+  virtual bool GetFunctionName(uint64_t addr, std::string* name, uint64_t* offset) = 0;
+
+  virtual bool Step(uint64_t rel_pc, Regs* regs, Memory* process_memory);
+
+  Memory* CreateGnuDebugdataMemory();
+
+  Memory* memory() { return memory_; }
+
+  const std::unordered_map<uint64_t, LoadInfo>& pt_loads() { return pt_loads_; }
+  uint64_t load_bias() { return load_bias_; }
+  void set_load_bias(uint64_t load_bias) { load_bias_ = load_bias; }
+
+  uint64_t dynamic_offset() { return dynamic_offset_; }
+  uint64_t dynamic_size() { return dynamic_size_; }
+  uint64_t eh_frame_offset() { return eh_frame_offset_; }
+  uint64_t eh_frame_size() { return eh_frame_size_; }
+  uint64_t gnu_debugdata_offset() { return gnu_debugdata_offset_; }
+  uint64_t gnu_debugdata_size() { return gnu_debugdata_size_; }
+
+ protected:
+  template <typename EhdrType, typename PhdrType, typename ShdrType>
+  bool ReadAllHeaders();
+
+  template <typename EhdrType, typename PhdrType>
+  bool ReadProgramHeaders(const EhdrType& ehdr);
+
+  template <typename EhdrType, typename ShdrType>
+  bool ReadSectionHeaders(const EhdrType& ehdr);
+
+  template <typename DynType>
+  bool GetSonameWithTemplate(std::string* soname);
+
+  virtual bool HandleType(uint64_t, uint32_t) { return false; }
+
+  Memory* memory_;
+  std::unordered_map<uint64_t, LoadInfo> pt_loads_;
+  uint64_t load_bias_ = 0;
+
+  // Stored elf data.
+  uint64_t dynamic_offset_ = 0;
+  uint64_t dynamic_size_ = 0;
+
+  uint64_t eh_frame_offset_ = 0;
+  uint64_t eh_frame_size_ = 0;
+
+  uint64_t debug_frame_offset_ = 0;
+  uint64_t debug_frame_size_ = 0;
+
+  uint64_t gnu_debugdata_offset_ = 0;
+  uint64_t gnu_debugdata_size_ = 0;
+
+  uint8_t soname_type_ = SONAME_UNKNOWN;
+  std::string soname_;
+};
+
+class ElfInterface32 : public ElfInterface {
+ public:
+  ElfInterface32(Memory* memory) : ElfInterface(memory) {}
+  virtual ~ElfInterface32() = default;
+
+  bool Init() override {
+    return ElfInterface::ReadAllHeaders<Elf32_Ehdr, Elf32_Phdr, Elf32_Shdr>();
+  }
+
+  void InitHeaders() override {
+  }
+
+  bool GetSoname(std::string* soname) override {
+    return ElfInterface::GetSonameWithTemplate<Elf32_Dyn>(soname);
+  }
+
+  bool GetFunctionName(uint64_t, std::string*, uint64_t*) override {
+    return false;
+  }
+};
+
+class ElfInterface64 : public ElfInterface {
+ public:
+  ElfInterface64(Memory* memory) : ElfInterface(memory) {}
+  virtual ~ElfInterface64() = default;
+
+  bool Init() override {
+    return ElfInterface::ReadAllHeaders<Elf64_Ehdr, Elf64_Phdr, Elf64_Shdr>();
+  }
+
+  void InitHeaders() override {
+  }
+
+  bool GetSoname(std::string* soname) override {
+    return ElfInterface::GetSonameWithTemplate<Elf64_Dyn>(soname);
+  }
+
+  bool GetFunctionName(uint64_t, std::string*, uint64_t*) override {
+    return false;
+  }
+};
+
+#endif  // _LIBUNWINDSTACK_ELF_INTERFACE_H
diff --git a/libunwindstack/ElfInterfaceArm.cpp b/libunwindstack/ElfInterfaceArm.cpp
new file mode 100644
index 0000000..e157320
--- /dev/null
+++ b/libunwindstack/ElfInterfaceArm.cpp
@@ -0,0 +1,127 @@
+/*
+ * Copyright (C) 2016 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 <elf.h>
+#include <stdint.h>
+
+#include "ArmExidx.h"
+#include "ElfInterface.h"
+#include "ElfInterfaceArm.h"
+#include "Machine.h"
+#include "Memory.h"
+#include "Regs.h"
+
+bool ElfInterfaceArm::FindEntry(uint32_t pc, uint64_t* entry_offset) {
+  if (start_offset_ == 0 || total_entries_ == 0) {
+    return false;
+  }
+
+  // Need to subtract the load_bias from the pc.
+  if (pc < load_bias_) {
+    return false;
+  }
+  pc -= load_bias_;
+
+  size_t first = 0;
+  size_t last = total_entries_;
+  while (first < last) {
+    size_t current = (first + last) / 2;
+    uint32_t addr = addrs_[current];
+    if (addr == 0) {
+      if (!GetPrel31Addr(start_offset_ + current * 8, &addr)) {
+        return false;
+      }
+      addrs_[current] = addr;
+    }
+    if (pc == addr) {
+      *entry_offset = start_offset_ + current * 8;
+      return true;
+    }
+    if (pc < addr) {
+      last = current;
+    } else {
+      first = current + 1;
+    }
+  }
+  if (last != 0) {
+    *entry_offset = start_offset_ + (last - 1) * 8;
+    return true;
+  }
+  return false;
+}
+
+bool ElfInterfaceArm::GetPrel31Addr(uint32_t offset, uint32_t* addr) {
+  uint32_t data;
+  if (!memory_->Read32(offset, &data)) {
+    return false;
+  }
+
+  // Sign extend the value if necessary.
+  int32_t value = (static_cast<int32_t>(data) << 1) >> 1;
+  *addr = offset + value;
+  return true;
+}
+
+#if !defined(PT_ARM_EXIDX)
+#define PT_ARM_EXIDX 0x70000001
+#endif
+
+bool ElfInterfaceArm::HandleType(uint64_t offset, uint32_t type) {
+  if (type != PT_ARM_EXIDX) {
+    return false;
+  }
+
+  Elf32_Phdr phdr;
+  if (!memory_->Read(offset, &phdr, &phdr.p_vaddr, sizeof(phdr.p_vaddr))) {
+    return true;
+  }
+  if (!memory_->Read(offset, &phdr, &phdr.p_memsz, sizeof(phdr.p_memsz))) {
+    return true;
+  }
+  // The load_bias_ should always be set by this time.
+  start_offset_ = phdr.p_vaddr - load_bias_;
+  total_entries_ = phdr.p_memsz / 8;
+  return true;
+}
+
+bool ElfInterfaceArm::Step(uint64_t pc, Regs* regs, Memory* process_memory) {
+  return StepExidx(pc, regs, process_memory) ||
+      ElfInterface32::Step(pc, regs, process_memory);
+}
+
+bool ElfInterfaceArm::StepExidx(uint64_t pc, Regs* regs, Memory* process_memory) {
+  RegsArm* regs_arm = reinterpret_cast<RegsArm*>(regs);
+  // First try arm, then try dwarf.
+  uint64_t entry_offset;
+  if (!FindEntry(pc, &entry_offset)) {
+    return false;
+  }
+  ArmExidx arm(regs_arm, memory_, process_memory);
+  arm.set_cfa(regs_arm->sp());
+  if (arm.ExtractEntryData(entry_offset) && arm.Eval()) {
+    // If the pc was not set, then use the LR registers for the PC.
+    if (!arm.pc_set()) {
+      regs_arm->set_pc((*regs_arm)[ARM_REG_LR]);
+      (*regs_arm)[ARM_REG_PC] = regs_arm->pc();
+    } else {
+      regs_arm->set_pc((*regs_arm)[ARM_REG_PC]);
+    }
+    regs_arm->set_sp(arm.cfa());
+    (*regs_arm)[ARM_REG_SP] = regs_arm->sp();
+    return true;
+  }
+  return false;
+}
diff --git a/libunwindstack/ElfInterfaceArm.h b/libunwindstack/ElfInterfaceArm.h
new file mode 100644
index 0000000..ece694f
--- /dev/null
+++ b/libunwindstack/ElfInterfaceArm.h
@@ -0,0 +1,90 @@
+/*
+ * Copyright (C) 2016 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 _LIBUNWINDSTACK_ELF_INTERFACE_ARM_H
+#define _LIBUNWINDSTACK_ELF_INTERFACE_ARM_H
+
+#include <elf.h>
+#include <stdint.h>
+
+#include <iterator>
+#include <unordered_map>
+
+#include "ElfInterface.h"
+#include "Memory.h"
+
+class ElfInterfaceArm : public ElfInterface32 {
+ public:
+  ElfInterfaceArm(Memory* memory) : ElfInterface32(memory) {}
+  virtual ~ElfInterfaceArm() = default;
+
+  class iterator : public std::iterator<std::bidirectional_iterator_tag, uint32_t> {
+   public:
+    iterator(ElfInterfaceArm* interface, size_t index) : interface_(interface), index_(index) { }
+
+    iterator& operator++() { index_++; return *this; }
+    iterator& operator++(int increment) { index_ += increment; return *this; }
+    iterator& operator--() { index_--; return *this; }
+    iterator& operator--(int decrement) { index_ -= decrement; return *this; }
+
+    bool operator==(const iterator& rhs) { return this->index_ == rhs.index_; }
+    bool operator!=(const iterator& rhs) { return this->index_ != rhs.index_; }
+
+    uint32_t operator*() {
+      uint32_t addr = interface_->addrs_[index_];
+      if (addr == 0) {
+        if (!interface_->GetPrel31Addr(interface_->start_offset_ + index_ * 8, &addr)) {
+          return 0;
+        }
+        interface_->addrs_[index_] = addr;
+      }
+      return addr;
+    }
+
+   private:
+    ElfInterfaceArm* interface_ = nullptr;
+    size_t index_ = 0;
+  };
+
+  iterator begin() { return iterator(this, 0); }
+  iterator end() { return iterator(this, total_entries_); }
+
+  bool GetPrel31Addr(uint32_t offset, uint32_t* addr);
+
+  bool FindEntry(uint32_t pc, uint64_t* entry_offset);
+
+  bool HandleType(uint64_t offset, uint32_t type) override;
+
+  bool Step(uint64_t pc, Regs* regs, Memory* process_memory) override;
+
+  bool StepExidx(uint64_t pc, Regs* regs, Memory* process_memory);
+
+  uint64_t start_offset() { return start_offset_; }
+
+  void set_start_offset(uint64_t start_offset) { start_offset_ = start_offset; }
+
+  size_t total_entries() { return total_entries_; }
+
+  void set_total_entries(size_t total_entries) { total_entries_ = total_entries; }
+
+ private:
+  uint64_t start_offset_ = 0;
+  size_t total_entries_ = 0;
+
+  std::unordered_map<size_t, uint32_t> addrs_;
+};
+
+#endif  // _LIBUNWINDSTACK_ELF_INTERFACE_ARM_H
diff --git a/libunwindstack/Machine.h b/libunwindstack/Machine.h
index db84271..323ce80 100644
--- a/libunwindstack/Machine.h
+++ b/libunwindstack/Machine.h
@@ -19,8 +19,6 @@
 
 #include <stdint.h>
 
-class Regs;
-
 enum ArmReg : uint16_t {
   ARM_REG_R0 = 0,
   ARM_REG_R1,
diff --git a/libunwindstack/MapInfo.h b/libunwindstack/MapInfo.h
new file mode 100644
index 0000000..8342904
--- /dev/null
+++ b/libunwindstack/MapInfo.h
@@ -0,0 +1,44 @@
+/*
+ * Copyright (C) 2016 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 _LIBUNWINDSTACK_MAP_INFO_H
+#define _LIBUNWINDSTACK_MAP_INFO_H
+
+#include <stdint.h>
+
+#include <string>
+
+// Forward declarations.
+class Elf;
+class Memory;
+
+struct MapInfo {
+  uint64_t start;
+  uint64_t end;
+  uint64_t offset;
+  uint16_t flags;
+  std::string name;
+  Elf* elf = nullptr;
+  // This value is only non-zero if the offset is non-zero but there is
+  // no elf signature found at that offset. This indicates that the
+  // entire file is represented by the Memory object returned by CreateMemory,
+  // instead of a portion of the file.
+  uint64_t elf_offset;
+
+  Memory* CreateMemory(pid_t pid);
+};
+
+#endif  // _LIBUNWINDSTACK_MAP_INFO_H
diff --git a/libunwindstack/Memory.cpp b/libunwindstack/Memory.cpp
index 336e4fe..1fcf842 100644
--- a/libunwindstack/Memory.cpp
+++ b/libunwindstack/Memory.cpp
@@ -48,14 +48,40 @@
   return false;
 }
 
+bool MemoryBuffer::Read(uint64_t addr, void* dst, size_t size) {
+  uint64_t last_read_byte;
+  if (__builtin_add_overflow(size, addr, &last_read_byte)) {
+    return false;
+  }
+  if (last_read_byte > raw_.size()) {
+    return false;
+  }
+  memcpy(dst, &raw_[addr], size);
+  return true;
+}
+
+uint8_t* MemoryBuffer::GetPtr(size_t offset) {
+  if (offset < raw_.size()) {
+    return &raw_[offset];
+  }
+  return nullptr;
+}
+
 MemoryFileAtOffset::~MemoryFileAtOffset() {
+  Clear();
+}
+
+void MemoryFileAtOffset::Clear() {
   if (data_) {
     munmap(&data_[-offset_], size_ + offset_);
     data_ = nullptr;
   }
 }
 
-bool MemoryFileAtOffset::Init(const std::string& file, uint64_t offset) {
+bool MemoryFileAtOffset::Init(const std::string& file, uint64_t offset, uint64_t size) {
+  // Clear out any previous data if it exists.
+  Clear();
+
   android::base::unique_fd fd(TEMP_FAILURE_RETRY(open(file.c_str(), O_RDONLY | O_CLOEXEC)));
   if (fd == -1) {
     return false;
@@ -71,6 +97,10 @@
   offset_ = offset & (getpagesize() - 1);
   uint64_t aligned_offset = offset & ~(getpagesize() - 1);
   size_ = buf.st_size - aligned_offset;
+  if (size < (UINT64_MAX - offset_) && size + offset_ < size_) {
+    // Truncate the mapped size.
+    size_ = size + offset_;
+  }
   void* map = mmap(nullptr, size_, PROT_READ, MAP_PRIVATE, fd, aligned_offset);
   if (map == MAP_FAILED) {
     return false;
@@ -91,6 +121,12 @@
 }
 
 static bool PtraceRead(pid_t pid, uint64_t addr, long* value) {
+#if !defined(__LP64__)
+  // Cannot read an address greater than 32 bits.
+  if (addr > UINT32_MAX) {
+    return false;
+  }
+#endif
   // ptrace() returns -1 and sets errno when the operation fails.
   // To disambiguate -1 from a valid result, we clear errno beforehand.
   errno = 0;
diff --git a/libunwindstack/Memory.h b/libunwindstack/Memory.h
index 5ab031d..c5316a1 100644
--- a/libunwindstack/Memory.h
+++ b/libunwindstack/Memory.h
@@ -22,10 +22,7 @@
 #include <unistd.h>
 
 #include <string>
-
-#include <android-base/unique_fd.h>
-
-constexpr bool kMemoryStatsEnabled = true;
+#include <vector>
 
 class Memory {
  public:
@@ -50,15 +47,34 @@
   }
 };
 
+class MemoryBuffer : public Memory {
+ public:
+  MemoryBuffer() = default;
+  virtual ~MemoryBuffer() = default;
+
+  bool Read(uint64_t addr, void* dst, size_t size) override;
+
+  uint8_t* GetPtr(size_t offset);
+
+  void Resize(size_t size) { raw_.resize(size); }
+
+  uint64_t Size() { return raw_.size(); }
+
+ private:
+  std::vector<uint8_t> raw_;
+};
+
 class MemoryFileAtOffset : public Memory {
  public:
   MemoryFileAtOffset() = default;
   virtual ~MemoryFileAtOffset();
 
-  bool Init(const std::string& file, uint64_t offset);
+  bool Init(const std::string& file, uint64_t offset, uint64_t size = UINT64_MAX);
 
   bool Read(uint64_t addr, void* dst, size_t size) override;
 
+  void Clear();
+
  protected:
   size_t size_ = 0;
   size_t offset_ = 0;
diff --git a/libunwindstack/Regs.cpp b/libunwindstack/Regs.cpp
new file mode 100644
index 0000000..adb6522
--- /dev/null
+++ b/libunwindstack/Regs.cpp
@@ -0,0 +1,237 @@
+/*
+ * Copyright (C) 2016 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 <assert.h>
+#include <elf.h>
+#include <stdint.h>
+#include <sys/ptrace.h>
+#include <sys/uio.h>
+
+#include <vector>
+
+#include "Elf.h"
+#include "ElfInterface.h"
+#include "Machine.h"
+#include "MapInfo.h"
+#include "Regs.h"
+#include "User.h"
+
+template <typename AddressType>
+uint64_t RegsTmpl<AddressType>::GetRelPc(Elf* elf, const MapInfo* map_info) {
+  uint64_t load_bias = 0;
+  if (elf->valid()) {
+    load_bias = elf->interface()->load_bias();
+  }
+
+  return pc_ - map_info->start + load_bias + map_info->elf_offset;
+}
+
+template <typename AddressType>
+bool RegsTmpl<AddressType>::GetReturnAddressFromDefault(Memory* memory, uint64_t* value) {
+  switch (return_loc_.type) {
+  case LOCATION_REGISTER:
+    assert(return_loc_.value < total_regs_);
+    *value = regs_[return_loc_.value];
+    return true;
+  case LOCATION_SP_OFFSET:
+    AddressType return_value;
+    if (!memory->Read(sp_ + return_loc_.value, &return_value, sizeof(return_value))) {
+      return false;
+    }
+    *value = return_value;
+    return true;
+  case LOCATION_UNKNOWN:
+  default:
+    return false;
+  }
+}
+
+RegsArm::RegsArm() : RegsTmpl<uint32_t>(ARM_REG_LAST, ARM_REG_SP,
+                                        Location(LOCATION_REGISTER, ARM_REG_LR)) {
+}
+
+uint64_t RegsArm::GetAdjustedPc(uint64_t rel_pc, Elf* elf) {
+  if (!elf->valid()) {
+    return rel_pc;
+  }
+
+  uint64_t load_bias = elf->interface()->load_bias();
+  if (rel_pc < load_bias) {
+    return rel_pc;
+  }
+  uint64_t adjusted_rel_pc = rel_pc - load_bias;
+
+  if (adjusted_rel_pc < 5) {
+    return rel_pc;
+  }
+
+  if (adjusted_rel_pc & 1) {
+    // This is a thumb instruction, it could be 2 or 4 bytes.
+    uint32_t value;
+    if (rel_pc < 5 || !elf->memory()->Read(adjusted_rel_pc - 5, &value, sizeof(value)) ||
+        (value & 0xe000f000) != 0xe000f000) {
+      return rel_pc - 2;
+    }
+  }
+  return rel_pc - 4;
+}
+
+RegsArm64::RegsArm64() : RegsTmpl<uint64_t>(ARM64_REG_LAST, ARM64_REG_SP,
+                                            Location(LOCATION_REGISTER, ARM64_REG_LR)) {
+}
+
+uint64_t RegsArm64::GetAdjustedPc(uint64_t rel_pc, Elf* elf) {
+  if (!elf->valid()) {
+    return rel_pc;
+  }
+
+  if (rel_pc < 4) {
+    return rel_pc;
+  }
+  return rel_pc - 4;
+}
+
+RegsX86::RegsX86() : RegsTmpl<uint32_t>(X86_REG_LAST, X86_REG_SP,
+                                        Location(LOCATION_SP_OFFSET, -4)) {
+}
+
+uint64_t RegsX86::GetAdjustedPc(uint64_t rel_pc, Elf* elf) {
+  if (!elf->valid()) {
+    return rel_pc;
+  }
+
+  if (rel_pc == 0) {
+    return 0;
+  }
+  return rel_pc - 1;
+}
+
+RegsX86_64::RegsX86_64() : RegsTmpl<uint64_t>(X86_64_REG_LAST, X86_64_REG_SP,
+                                              Location(LOCATION_SP_OFFSET, -8)) {
+}
+
+uint64_t RegsX86_64::GetAdjustedPc(uint64_t rel_pc, Elf* elf) {
+  if (!elf->valid()) {
+    return rel_pc;
+  }
+
+  if (rel_pc == 0) {
+    return 0;
+  }
+
+  return rel_pc - 1;
+}
+
+static Regs* ReadArm(void* remote_data) {
+  arm_user_regs* user = reinterpret_cast<arm_user_regs*>(remote_data);
+
+  RegsArm* regs = new RegsArm();
+  memcpy(regs->RawData(), &user->regs[0], ARM_REG_LAST * sizeof(uint32_t));
+
+  regs->set_pc(user->regs[ARM_REG_PC]);
+  regs->set_sp(user->regs[ARM_REG_SP]);
+
+  return regs;
+}
+
+static Regs* ReadArm64(void* remote_data) {
+  arm64_user_regs* user = reinterpret_cast<arm64_user_regs*>(remote_data);
+
+  RegsArm64* regs = new RegsArm64();
+  memcpy(regs->RawData(), &user->regs[0], (ARM64_REG_R31 + 1) * sizeof(uint64_t));
+  regs->set_pc(user->pc);
+  regs->set_sp(user->sp);
+
+  return regs;
+}
+
+static Regs* ReadX86(void* remote_data) {
+  x86_user_regs* user = reinterpret_cast<x86_user_regs*>(remote_data);
+
+  RegsX86* regs = new RegsX86();
+  (*regs)[X86_REG_EAX] = user->eax;
+  (*regs)[X86_REG_EBX] = user->ebx;
+  (*regs)[X86_REG_ECX] = user->ecx;
+  (*regs)[X86_REG_EDX] = user->edx;
+  (*regs)[X86_REG_EBP] = user->ebp;
+  (*regs)[X86_REG_EDI] = user->edi;
+  (*regs)[X86_REG_ESI] = user->esi;
+  (*regs)[X86_REG_ESP] = user->esp;
+  (*regs)[X86_REG_EIP] = user->eip;
+
+  regs->set_pc(user->eip);
+  regs->set_sp(user->esp);
+
+  return regs;
+}
+
+static Regs* ReadX86_64(void* remote_data) {
+  x86_64_user_regs* user = reinterpret_cast<x86_64_user_regs*>(remote_data);
+
+  RegsX86_64* regs = new RegsX86_64();
+  (*regs)[X86_64_REG_RAX] = user->rax;
+  (*regs)[X86_64_REG_RBX] = user->rbx;
+  (*regs)[X86_64_REG_RCX] = user->rcx;
+  (*regs)[X86_64_REG_RDX] = user->rdx;
+  (*regs)[X86_64_REG_R8] = user->r8;
+  (*regs)[X86_64_REG_R9] = user->r9;
+  (*regs)[X86_64_REG_R10] = user->r10;
+  (*regs)[X86_64_REG_R11] = user->r11;
+  (*regs)[X86_64_REG_R12] = user->r12;
+  (*regs)[X86_64_REG_R13] = user->r13;
+  (*regs)[X86_64_REG_R14] = user->r14;
+  (*regs)[X86_64_REG_R15] = user->r15;
+  (*regs)[X86_64_REG_RDI] = user->rdi;
+  (*regs)[X86_64_REG_RSI] = user->rsi;
+  (*regs)[X86_64_REG_RBP] = user->rbp;
+  (*regs)[X86_64_REG_RSP] = user->rsp;
+  (*regs)[X86_64_REG_RIP] = user->rip;
+
+  regs->set_pc(user->rip);
+  regs->set_sp(user->rsp);
+
+  return regs;
+}
+
+// This function assumes that reg_data is already aligned to a 64 bit value.
+// If not this could crash with an unaligned access.
+Regs* Regs::RemoteGet(pid_t pid, uint32_t* machine_type) {
+  // Make the buffer large enough to contain the largest registers type.
+  std::vector<uint64_t> buffer(MAX_USER_REGS_SIZE / sizeof(uint64_t));
+  struct iovec io;
+  io.iov_base = buffer.data();
+  io.iov_len = buffer.size() * sizeof(uint64_t);
+
+  if (ptrace(PTRACE_GETREGSET, pid, NT_PRSTATUS, reinterpret_cast<void*>(&io)) == -1) {
+    return nullptr;
+  }
+
+  switch (io.iov_len) {
+  case sizeof(x86_user_regs):
+    *machine_type = EM_386;
+    return ReadX86(buffer.data());
+  case sizeof(x86_64_user_regs):
+    *machine_type = EM_X86_64;
+    return ReadX86_64(buffer.data());
+  case sizeof(arm_user_regs):
+    *machine_type = EM_ARM;
+    return ReadArm(buffer.data());
+  case sizeof(arm64_user_regs):
+    *machine_type = EM_AARCH64;
+    return ReadArm64(buffer.data());
+  }
+  return nullptr;
+}
diff --git a/libunwindstack/Regs.h b/libunwindstack/Regs.h
index 2766c6f..718fc85 100644
--- a/libunwindstack/Regs.h
+++ b/libunwindstack/Regs.h
@@ -21,57 +21,107 @@
 
 #include <vector>
 
+// Forward declarations.
+class Elf;
+struct MapInfo;
+
 class Regs {
  public:
-  Regs(uint16_t pc_reg, uint16_t sp_reg, uint16_t total_regs)
-      : pc_reg_(pc_reg), sp_reg_(sp_reg), total_regs_(total_regs) {
-  }
+  enum LocationEnum : uint8_t {
+    LOCATION_UNKNOWN = 0,
+    LOCATION_REGISTER,
+    LOCATION_SP_OFFSET,
+  };
+
+  struct Location {
+    Location(LocationEnum type, int16_t value) : type(type), value(value) {}
+
+    LocationEnum type;
+    int16_t value;
+  };
+
+  Regs(uint16_t total_regs, uint16_t sp_reg, const Location& return_loc)
+      : total_regs_(total_regs), sp_reg_(sp_reg), return_loc_(return_loc) {}
   virtual ~Regs() = default;
 
-  uint16_t pc_reg() { return pc_reg_; }
-  uint16_t sp_reg() { return sp_reg_; }
-  uint16_t total_regs() { return total_regs_; }
-
-  virtual void* raw_data() = 0;
+  virtual void* RawData() = 0;
   virtual uint64_t pc() = 0;
   virtual uint64_t sp() = 0;
 
+  virtual bool GetReturnAddressFromDefault(Memory* memory, uint64_t* value) = 0;
+
+  virtual uint64_t GetRelPc(Elf* elf, const MapInfo* map_info) = 0;
+
+  virtual uint64_t GetAdjustedPc(uint64_t rel_pc, Elf* elf) = 0;
+
+  uint16_t sp_reg() { return sp_reg_; }
+  uint16_t total_regs() { return total_regs_; }
+
+  static Regs* RemoteGet(pid_t pid, uint32_t* machine_type);
+
  protected:
-  uint16_t pc_reg_;
-  uint16_t sp_reg_;
   uint16_t total_regs_;
+  uint16_t sp_reg_;
+  Location return_loc_;
 };
 
 template <typename AddressType>
 class RegsTmpl : public Regs {
  public:
-  RegsTmpl(uint16_t pc_reg, uint16_t sp_reg, uint16_t total_regs)
-      : Regs(pc_reg, sp_reg, total_regs), regs_(total_regs) {}
+  RegsTmpl(uint16_t total_regs, uint16_t sp_reg, Location return_loc)
+      : Regs(total_regs, sp_reg, return_loc), regs_(total_regs) {}
   virtual ~RegsTmpl() = default;
 
-  uint64_t pc() override { return regs_[pc_reg_]; }
-  uint64_t sp() override { return regs_[sp_reg_]; }
+  uint64_t GetRelPc(Elf* elf, const MapInfo* map_info) override;
+
+  bool GetReturnAddressFromDefault(Memory* memory, uint64_t* value) override;
+
+  uint64_t pc() override { return pc_; }
+  uint64_t sp() override { return sp_; }
+
+  void set_pc(AddressType pc) { pc_ = pc; }
+  void set_sp(AddressType sp) { sp_ = sp; }
 
   inline AddressType& operator[](size_t reg) { return regs_[reg]; }
 
-  void* raw_data() override { return regs_.data(); }
+  void* RawData() override { return regs_.data(); }
 
- private:
+ protected:
+  AddressType pc_;
+  AddressType sp_;
   std::vector<AddressType> regs_;
 };
 
-class Regs32 : public RegsTmpl<uint32_t> {
+class RegsArm : public RegsTmpl<uint32_t> {
  public:
-  Regs32(uint16_t pc_reg, uint16_t sp_reg, uint16_t total_regs)
-      : RegsTmpl(pc_reg, sp_reg, total_regs) {}
-  virtual ~Regs32() = default;
+  RegsArm();
+  virtual ~RegsArm() = default;
+
+  uint64_t GetAdjustedPc(uint64_t rel_pc, Elf* elf) override;
 };
 
-class Regs64 : public RegsTmpl<uint64_t> {
+class RegsArm64 : public RegsTmpl<uint64_t> {
  public:
-  Regs64(uint16_t pc_reg, uint16_t sp_reg, uint16_t total_regs)
-      : RegsTmpl(pc_reg, sp_reg, total_regs) {}
-  virtual ~Regs64() = default;
+  RegsArm64();
+  virtual ~RegsArm64() = default;
+
+  uint64_t GetAdjustedPc(uint64_t rel_pc, Elf* elf) override;
+};
+
+class RegsX86 : public RegsTmpl<uint32_t> {
+ public:
+  RegsX86();
+  virtual ~RegsX86() = default;
+
+  uint64_t GetAdjustedPc(uint64_t rel_pc, Elf* elf) override;
+};
+
+class RegsX86_64 : public RegsTmpl<uint64_t> {
+ public:
+  RegsX86_64();
+  virtual ~RegsX86_64() = default;
+
+  uint64_t GetAdjustedPc(uint64_t rel_pc, Elf* elf) override;
 };
 
 #endif  // _LIBUNWINDSTACK_REGS_H
diff --git a/libunwindstack/User.h b/libunwindstack/User.h
new file mode 100644
index 0000000..a695467
--- /dev/null
+++ b/libunwindstack/User.h
@@ -0,0 +1,96 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef _LIBUNWINDSTACK_USER_H
+#define _LIBUNWINDSTACK_USER_H
+
+struct x86_user_regs {
+  uint32_t ebx;
+  uint32_t ecx;
+  uint32_t edx;
+  uint32_t esi;
+  uint32_t edi;
+  uint32_t ebp;
+  uint32_t eax;
+  uint32_t xds;
+  uint32_t xes;
+  uint32_t xfs;
+  uint32_t xgs;
+  uint32_t orig_eax;
+  uint32_t eip;
+  uint32_t xcs;
+  uint32_t eflags;
+  uint32_t esp;
+  uint32_t xss;
+};
+
+struct x86_64_user_regs {
+  uint64_t r15;
+  uint64_t r14;
+  uint64_t r13;
+  uint64_t r12;
+  uint64_t rbp;
+  uint64_t rbx;
+  uint64_t r11;
+  uint64_t r10;
+  uint64_t r9;
+  uint64_t r8;
+  uint64_t rax;
+  uint64_t rcx;
+  uint64_t rdx;
+  uint64_t rsi;
+  uint64_t rdi;
+  uint64_t orig_rax;
+  uint64_t rip;
+  uint64_t cs;
+  uint64_t eflags;
+  uint64_t rsp;
+  uint64_t ss;
+  uint64_t fs_base;
+  uint64_t gs_base;
+  uint64_t ds;
+  uint64_t es;
+  uint64_t fs;
+  uint64_t gs;
+};
+
+struct arm_user_regs {
+  uint32_t regs[18];
+};
+
+struct arm64_user_regs {
+  uint64_t regs[31];
+  uint64_t sp;
+  uint64_t pc;
+  uint64_t pstate;
+};
+
+// The largest user structure.
+constexpr size_t MAX_USER_REGS_SIZE = sizeof(arm64_user_regs) + 10;
+
+#endif  // _LIBUNWINDSTACK_USER_H
diff --git a/libunwindstack/tests/ArmExidxDecodeTest.cpp b/libunwindstack/tests/ArmExidxDecodeTest.cpp
index 9ea917a..4fff48e 100644
--- a/libunwindstack/tests/ArmExidxDecodeTest.cpp
+++ b/libunwindstack/tests/ArmExidxDecodeTest.cpp
@@ -24,6 +24,7 @@
 #include <gtest/gtest.h>
 
 #include "ArmExidx.h"
+#include "Regs.h"
 #include "Log.h"
 
 #include "LogFake.h"
@@ -38,12 +39,14 @@
       process_memory = &process_memory_;
     }
 
-    regs32_.reset(new Regs32(0, 1, 32));
-    for (size_t i = 0; i < 32; i++) {
-      (*regs32_)[i] = 0;
+    regs_arm_.reset(new RegsArm());
+    for (size_t i = 0; i < regs_arm_->total_regs(); i++) {
+      (*regs_arm_)[i] = 0;
     }
+    regs_arm_->set_pc(0);
+    regs_arm_->set_sp(0);
 
-    exidx_.reset(new ArmExidx(regs32_.get(), &elf_memory_, process_memory));
+    exidx_.reset(new ArmExidx(regs_arm_.get(), &elf_memory_, process_memory));
     if (log_) {
       exidx_->set_log(true);
       exidx_->set_log_indent(0);
@@ -66,7 +69,7 @@
   }
 
   std::unique_ptr<ArmExidx> exidx_;
-  std::unique_ptr<Regs32> regs32_;
+  std::unique_ptr<RegsArm> regs_arm_;
   std::deque<uint8_t>* data_;
 
   MemoryFake elf_memory_;
@@ -78,6 +81,7 @@
   // 00xxxxxx: vsp = vsp + (xxxxxx << 2) + 4
   data_->push_back(0x00);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind vsp = vsp + 4\n", GetFakeLogPrint());
@@ -90,6 +94,7 @@
   data_->clear();
   data_->push_back(0x01);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind vsp = vsp + 8\n", GetFakeLogPrint());
@@ -102,6 +107,7 @@
   data_->clear();
   data_->push_back(0x3f);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind vsp = vsp + 256\n", GetFakeLogPrint());
@@ -115,6 +121,7 @@
   // 01xxxxxx: vsp = vsp - (xxxxxx << 2) + 4
   data_->push_back(0x40);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind vsp = vsp - 4\n", GetFakeLogPrint());
@@ -127,6 +134,7 @@
   data_->clear();
   data_->push_back(0x41);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind vsp = vsp - 8\n", GetFakeLogPrint());
@@ -139,6 +147,7 @@
   data_->clear();
   data_->push_back(0x7f);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind vsp = vsp - 256\n", GetFakeLogPrint());
@@ -164,26 +173,29 @@
 
 TEST_P(ArmExidxDecodeTest, pop_up_to_12) {
   // 1000iiii iiiiiiii: Pop up to 12 integer registers
-  data_->push_back(0x80);
-  data_->push_back(0x01);
-  process_memory_.SetData(0x10000, 0x10);
+  data_->push_back(0x88);
+  data_->push_back(0x00);
+  process_memory_.SetData32(0x10000, 0x10);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_TRUE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
-    ASSERT_EQ("4 unwind pop {r4}\n", GetFakeLogPrint());
+    ASSERT_EQ("4 unwind pop {r15}\n", GetFakeLogPrint());
   } else {
     ASSERT_EQ("", GetFakeLogPrint());
   }
   ASSERT_EQ(0x10004U, exidx_->cfa());
-  ASSERT_EQ(0x10U, (*exidx_->regs())[4]);
+  ASSERT_EQ(0x10U, (*exidx_->regs())[15]);
 
   ResetLogs();
   data_->push_back(0x8f);
   data_->push_back(0xff);
   for (size_t i = 0; i < 12; i++) {
-    process_memory_.SetData(0x10004 + i * 4, i + 0x20);
+    process_memory_.SetData32(0x10004 + i * 4, i + 0x20);
   }
+  exidx_->set_pc_set(false);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_TRUE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind pop {r4, r5, r6, r7, r8, r9, r10, r11, r12, r13, r14, r15}\n",
@@ -211,10 +223,12 @@
   exidx_->set_cfa(0x10034);
   data_->push_back(0x81);
   data_->push_back(0x28);
-  process_memory_.SetData(0x10034, 0x11);
-  process_memory_.SetData(0x10038, 0x22);
-  process_memory_.SetData(0x1003c, 0x33);
+  process_memory_.SetData32(0x10034, 0x11);
+  process_memory_.SetData32(0x10038, 0x22);
+  process_memory_.SetData32(0x1003c, 0x33);
+  exidx_->set_pc_set(false);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind pop {r7, r9, r12}\n", GetFakeLogPrint());
@@ -231,11 +245,12 @@
   // 1001nnnn: Set vsp = r[nnnn] (nnnn != 13, 15)
   exidx_->set_cfa(0x100);
   for (size_t i = 0; i < 15; i++) {
-    (*regs32_)[i] = i + 1;
+    (*regs_arm_)[i] = i + 1;
   }
 
   data_->push_back(0x90);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind vsp = r0\n", GetFakeLogPrint());
@@ -247,6 +262,7 @@
   ResetLogs();
   data_->push_back(0x93);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind vsp = r3\n", GetFakeLogPrint());
@@ -258,6 +274,7 @@
   ResetLogs();
   data_->push_back(0x9e);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind vsp = r14\n", GetFakeLogPrint());
@@ -295,8 +312,9 @@
 TEST_P(ArmExidxDecodeTest, pop_registers) {
   // 10100nnn: Pop r4-r[4+nnn]
   data_->push_back(0xa0);
-  process_memory_.SetData(0x10000, 0x14);
+  process_memory_.SetData32(0x10000, 0x14);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind pop {r4}\n", GetFakeLogPrint());
@@ -308,11 +326,12 @@
 
   ResetLogs();
   data_->push_back(0xa3);
-  process_memory_.SetData(0x10004, 0x20);
-  process_memory_.SetData(0x10008, 0x30);
-  process_memory_.SetData(0x1000c, 0x40);
-  process_memory_.SetData(0x10010, 0x50);
+  process_memory_.SetData32(0x10004, 0x20);
+  process_memory_.SetData32(0x10008, 0x30);
+  process_memory_.SetData32(0x1000c, 0x40);
+  process_memory_.SetData32(0x10010, 0x50);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind pop {r4-r7}\n", GetFakeLogPrint());
@@ -327,15 +346,16 @@
 
   ResetLogs();
   data_->push_back(0xa7);
-  process_memory_.SetData(0x10014, 0x41);
-  process_memory_.SetData(0x10018, 0x51);
-  process_memory_.SetData(0x1001c, 0x61);
-  process_memory_.SetData(0x10020, 0x71);
-  process_memory_.SetData(0x10024, 0x81);
-  process_memory_.SetData(0x10028, 0x91);
-  process_memory_.SetData(0x1002c, 0xa1);
-  process_memory_.SetData(0x10030, 0xb1);
+  process_memory_.SetData32(0x10014, 0x41);
+  process_memory_.SetData32(0x10018, 0x51);
+  process_memory_.SetData32(0x1001c, 0x61);
+  process_memory_.SetData32(0x10020, 0x71);
+  process_memory_.SetData32(0x10024, 0x81);
+  process_memory_.SetData32(0x10028, 0x91);
+  process_memory_.SetData32(0x1002c, 0xa1);
+  process_memory_.SetData32(0x10030, 0xb1);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind pop {r4-r11}\n", GetFakeLogPrint());
@@ -356,9 +376,10 @@
 TEST_P(ArmExidxDecodeTest, pop_registers_with_r14) {
   // 10101nnn: Pop r4-r[4+nnn], r14
   data_->push_back(0xa8);
-  process_memory_.SetData(0x10000, 0x12);
-  process_memory_.SetData(0x10004, 0x22);
+  process_memory_.SetData32(0x10000, 0x12);
+  process_memory_.SetData32(0x10004, 0x22);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind pop {r4, r14}\n", GetFakeLogPrint());
@@ -371,12 +392,13 @@
 
   ResetLogs();
   data_->push_back(0xab);
-  process_memory_.SetData(0x10008, 0x1);
-  process_memory_.SetData(0x1000c, 0x2);
-  process_memory_.SetData(0x10010, 0x3);
-  process_memory_.SetData(0x10014, 0x4);
-  process_memory_.SetData(0x10018, 0x5);
+  process_memory_.SetData32(0x10008, 0x1);
+  process_memory_.SetData32(0x1000c, 0x2);
+  process_memory_.SetData32(0x10010, 0x3);
+  process_memory_.SetData32(0x10014, 0x4);
+  process_memory_.SetData32(0x10018, 0x5);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind pop {r4-r7, r14}\n", GetFakeLogPrint());
@@ -392,16 +414,17 @@
 
   ResetLogs();
   data_->push_back(0xaf);
-  process_memory_.SetData(0x1001c, 0x1a);
-  process_memory_.SetData(0x10020, 0x2a);
-  process_memory_.SetData(0x10024, 0x3a);
-  process_memory_.SetData(0x10028, 0x4a);
-  process_memory_.SetData(0x1002c, 0x5a);
-  process_memory_.SetData(0x10030, 0x6a);
-  process_memory_.SetData(0x10034, 0x7a);
-  process_memory_.SetData(0x10038, 0x8a);
-  process_memory_.SetData(0x1003c, 0x9a);
+  process_memory_.SetData32(0x1001c, 0x1a);
+  process_memory_.SetData32(0x10020, 0x2a);
+  process_memory_.SetData32(0x10024, 0x3a);
+  process_memory_.SetData32(0x10028, 0x4a);
+  process_memory_.SetData32(0x1002c, 0x5a);
+  process_memory_.SetData32(0x10030, 0x6a);
+  process_memory_.SetData32(0x10034, 0x7a);
+  process_memory_.SetData32(0x10038, 0x8a);
+  process_memory_.SetData32(0x1003c, 0x9a);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind pop {r4-r11, r14}\n", GetFakeLogPrint());
@@ -550,8 +573,9 @@
   // 10110001 0000iiii: Pop integer registers {r0, r1, r2, r3}
   data_->push_back(0xb1);
   data_->push_back(0x01);
-  process_memory_.SetData(0x10000, 0x45);
+  process_memory_.SetData32(0x10000, 0x45);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind pop {r0}\n", GetFakeLogPrint());
@@ -564,9 +588,10 @@
   ResetLogs();
   data_->push_back(0xb1);
   data_->push_back(0x0a);
-  process_memory_.SetData(0x10004, 0x23);
-  process_memory_.SetData(0x10008, 0x24);
+  process_memory_.SetData32(0x10004, 0x23);
+  process_memory_.SetData32(0x10008, 0x24);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind pop {r1, r3}\n", GetFakeLogPrint());
@@ -580,11 +605,12 @@
   ResetLogs();
   data_->push_back(0xb1);
   data_->push_back(0x0f);
-  process_memory_.SetData(0x1000c, 0x65);
-  process_memory_.SetData(0x10010, 0x54);
-  process_memory_.SetData(0x10014, 0x43);
-  process_memory_.SetData(0x10018, 0x32);
+  process_memory_.SetData32(0x1000c, 0x65);
+  process_memory_.SetData32(0x10010, 0x54);
+  process_memory_.SetData32(0x10014, 0x43);
+  process_memory_.SetData32(0x10018, 0x32);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind pop {r0, r1, r2, r3}\n", GetFakeLogPrint());
@@ -603,6 +629,7 @@
   data_->push_back(0xb2);
   data_->push_back(0x7f);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind vsp = vsp + 1024\n", GetFakeLogPrint());
@@ -616,6 +643,7 @@
   data_->push_back(0xff);
   data_->push_back(0x02);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind vsp = vsp + 2048\n", GetFakeLogPrint());
@@ -630,6 +658,7 @@
   data_->push_back(0x82);
   data_->push_back(0x30);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind vsp = vsp + 3147776\n", GetFakeLogPrint());
@@ -644,6 +673,7 @@
   data_->push_back(0xb3);
   data_->push_back(0x00);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind pop {d0}\n", GetFakeLogPrint());
@@ -656,6 +686,7 @@
   data_->push_back(0xb3);
   data_->push_back(0x48);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind pop {d4-d12}\n", GetFakeLogPrint());
@@ -669,6 +700,7 @@
   // 10111nnn: Pop VFP double precision registers D[8]-D[8+nnn] by FSTMFDX
   data_->push_back(0xb8);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind pop {d8}\n", GetFakeLogPrint());
@@ -680,6 +712,7 @@
   ResetLogs();
   data_->push_back(0xbb);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind pop {d8-d11}\n", GetFakeLogPrint());
@@ -691,6 +724,7 @@
   ResetLogs();
   data_->push_back(0xbf);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind pop {d8-d15}\n", GetFakeLogPrint());
@@ -704,6 +738,7 @@
   // 11000nnn: Intel Wireless MMX pop wR[10]-wR[10+nnn] (nnn != 6, 7)
   data_->push_back(0xc0);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind pop {wR10}\n", GetFakeLogPrint());
@@ -715,6 +750,7 @@
   ResetLogs();
   data_->push_back(0xc2);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind pop {wR10-wR12}\n", GetFakeLogPrint());
@@ -726,6 +762,7 @@
   ResetLogs();
   data_->push_back(0xc5);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind pop {wR10-wR15}\n", GetFakeLogPrint());
@@ -740,6 +777,7 @@
   data_->push_back(0xc6);
   data_->push_back(0x00);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind pop {wR0}\n", GetFakeLogPrint());
@@ -752,6 +790,7 @@
   data_->push_back(0xc6);
   data_->push_back(0x25);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind pop {wR2-wR7}\n", GetFakeLogPrint());
@@ -764,6 +803,7 @@
   data_->push_back(0xc6);
   data_->push_back(0xff);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind pop {wR15-wR30}\n", GetFakeLogPrint());
@@ -778,6 +818,7 @@
   data_->push_back(0xc7);
   data_->push_back(0x01);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind pop {wCGR0}\n", GetFakeLogPrint());
@@ -790,6 +831,7 @@
   data_->push_back(0xc7);
   data_->push_back(0x0a);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind pop {wCGR1, wCGR3}\n", GetFakeLogPrint());
@@ -802,6 +844,7 @@
   data_->push_back(0xc7);
   data_->push_back(0x0f);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind pop {wCGR0, wCGR1, wCGR2, wCGR3}\n", GetFakeLogPrint());
@@ -816,6 +859,7 @@
   data_->push_back(0xc8);
   data_->push_back(0x00);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind pop {d16}\n", GetFakeLogPrint());
@@ -828,6 +872,7 @@
   data_->push_back(0xc8);
   data_->push_back(0x14);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind pop {d17-d21}\n", GetFakeLogPrint());
@@ -840,6 +885,7 @@
   data_->push_back(0xc8);
   data_->push_back(0xff);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind pop {d31-d46}\n", GetFakeLogPrint());
@@ -854,6 +900,7 @@
   data_->push_back(0xc9);
   data_->push_back(0x00);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind pop {d0}\n", GetFakeLogPrint());
@@ -866,6 +913,7 @@
   data_->push_back(0xc9);
   data_->push_back(0x23);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind pop {d2-d5}\n", GetFakeLogPrint());
@@ -878,6 +926,7 @@
   data_->push_back(0xc9);
   data_->push_back(0xff);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind pop {d15-d30}\n", GetFakeLogPrint());
@@ -891,6 +940,7 @@
   // 11010nnn: Pop VFP double precision registers D[8]-D[8+nnn] by VPUSH
   data_->push_back(0xd0);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind pop {d8}\n", GetFakeLogPrint());
@@ -902,6 +952,7 @@
   ResetLogs();
   data_->push_back(0xd2);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind pop {d8-d10}\n", GetFakeLogPrint());
@@ -913,6 +964,7 @@
   ResetLogs();
   data_->push_back(0xd7);
   ASSERT_TRUE(exidx_->Decode());
+  ASSERT_FALSE(exidx_->pc_set());
   ASSERT_EQ("", GetFakeLogBuf());
   if (log_) {
     ASSERT_EQ("4 unwind pop {d8-d15}\n", GetFakeLogPrint());
@@ -989,4 +1041,54 @@
   }
 }
 
+TEST_P(ArmExidxDecodeTest, eval_multiple_decodes) {
+  // vsp = vsp + 4
+  data_->push_back(0x00);
+  // vsp = vsp + 8
+  data_->push_back(0x02);
+  // Finish
+  data_->push_back(0xb0);
+
+  ASSERT_TRUE(exidx_->Eval());
+  if (log_) {
+    ASSERT_EQ("4 unwind vsp = vsp + 4\n"
+              "4 unwind vsp = vsp + 12\n"
+              "4 unwind finish\n", GetFakeLogPrint());
+  } else {
+    ASSERT_EQ("", GetFakeLogPrint());
+  }
+  ASSERT_EQ(0x10010U, exidx_->cfa());
+  ASSERT_FALSE(exidx_->pc_set());
+}
+
+TEST_P(ArmExidxDecodeTest, eval_pc_set) {
+  // vsp = vsp + 4
+  data_->push_back(0x00);
+  // vsp = vsp + 8
+  data_->push_back(0x02);
+  // Pop {r15}
+  data_->push_back(0x88);
+  data_->push_back(0x00);
+  // vsp = vsp + 8
+  data_->push_back(0x02);
+  // Finish
+  data_->push_back(0xb0);
+
+  process_memory_.SetData32(0x10010, 0x10);
+
+  ASSERT_TRUE(exidx_->Eval());
+  if (log_) {
+    ASSERT_EQ("4 unwind vsp = vsp + 4\n"
+              "4 unwind vsp = vsp + 12\n"
+              "4 unwind pop {r15}\n"
+              "4 unwind vsp = vsp + 12\n"
+              "4 unwind finish\n", GetFakeLogPrint());
+  } else {
+    ASSERT_EQ("", GetFakeLogPrint());
+  }
+  ASSERT_EQ(0x10020U, exidx_->cfa());
+  ASSERT_TRUE(exidx_->pc_set());
+  ASSERT_EQ(0x10U, (*exidx_->regs())[15]);
+}
+
 INSTANTIATE_TEST_CASE_P(, ArmExidxDecodeTest, ::testing::Values("logging", "no_logging"));
diff --git a/libunwindstack/tests/ArmExidxExtractTest.cpp b/libunwindstack/tests/ArmExidxExtractTest.cpp
index 021765a..aed75bf 100644
--- a/libunwindstack/tests/ArmExidxExtractTest.cpp
+++ b/libunwindstack/tests/ArmExidxExtractTest.cpp
@@ -53,16 +53,16 @@
 }
 
 TEST_F(ArmExidxExtractTest, cant_unwind) {
-  elf_memory_.SetData(0x1000, 0x7fff2340);
-  elf_memory_.SetData(0x1004, 1);
+  elf_memory_.SetData32(0x1000, 0x7fff2340);
+  elf_memory_.SetData32(0x1004, 1);
   ASSERT_FALSE(exidx_->ExtractEntryData(0x1000));
   ASSERT_EQ(ARM_STATUS_NO_UNWIND, exidx_->status());
   ASSERT_TRUE(data_->empty());
 }
 
 TEST_F(ArmExidxExtractTest, compact) {
-  elf_memory_.SetData(0x4000, 0x7ffa3000);
-  elf_memory_.SetData(0x4004, 0x80a8b0b0);
+  elf_memory_.SetData32(0x4000, 0x7ffa3000);
+  elf_memory_.SetData32(0x4004, 0x80a8b0b0);
   ASSERT_TRUE(exidx_->ExtractEntryData(0x4000));
   ASSERT_EQ(3U, data_->size());
   ASSERT_EQ(0xa8, data_->at(0));
@@ -71,8 +71,8 @@
 
   // Missing finish gets added.
   elf_memory_.Clear();
-  elf_memory_.SetData(0x534, 0x7ffa3000);
-  elf_memory_.SetData(0x538, 0x80a1a2a3);
+  elf_memory_.SetData32(0x534, 0x7ffa3000);
+  elf_memory_.SetData32(0x538, 0x80a1a2a3);
   ASSERT_TRUE(exidx_->ExtractEntryData(0x534));
   ASSERT_EQ(4U, data_->size());
   ASSERT_EQ(0xa1, data_->at(0));
@@ -82,29 +82,29 @@
 }
 
 TEST_F(ArmExidxExtractTest, compact_non_zero_personality) {
-  elf_memory_.SetData(0x4000, 0x7ffa3000);
+  elf_memory_.SetData32(0x4000, 0x7ffa3000);
 
   uint32_t compact_value = 0x80a8b0b0;
   for (size_t i = 1; i < 16; i++) {
-    elf_memory_.SetData(0x4004, compact_value | (i << 24));
+    elf_memory_.SetData32(0x4004, compact_value | (i << 24));
     ASSERT_FALSE(exidx_->ExtractEntryData(0x4000));
     ASSERT_EQ(ARM_STATUS_INVALID_PERSONALITY, exidx_->status());
   }
 }
 
 TEST_F(ArmExidxExtractTest, second_read_compact_personality_1_2) {
-  elf_memory_.SetData(0x5000, 0x1234);
-  elf_memory_.SetData(0x5004, 0x00001230);
-  elf_memory_.SetData(0x6234, 0x8100f3b0);
+  elf_memory_.SetData32(0x5000, 0x1234);
+  elf_memory_.SetData32(0x5004, 0x00001230);
+  elf_memory_.SetData32(0x6234, 0x8100f3b0);
   ASSERT_TRUE(exidx_->ExtractEntryData(0x5000));
   ASSERT_EQ(2U, data_->size());
   ASSERT_EQ(0xf3, data_->at(0));
   ASSERT_EQ(0xb0, data_->at(1));
 
   elf_memory_.Clear();
-  elf_memory_.SetData(0x5000, 0x1234);
-  elf_memory_.SetData(0x5004, 0x00001230);
-  elf_memory_.SetData(0x6234, 0x8200f3f4);
+  elf_memory_.SetData32(0x5000, 0x1234);
+  elf_memory_.SetData32(0x5004, 0x00001230);
+  elf_memory_.SetData32(0x6234, 0x8200f3f4);
   ASSERT_TRUE(exidx_->ExtractEntryData(0x5000));
   ASSERT_EQ(3U, data_->size());
   ASSERT_EQ(0xf3, data_->at(0));
@@ -112,10 +112,10 @@
   ASSERT_EQ(0xb0, data_->at(2));
 
   elf_memory_.Clear();
-  elf_memory_.SetData(0x5000, 0x1234);
-  elf_memory_.SetData(0x5004, 0x00001230);
-  elf_memory_.SetData(0x6234, 0x8201f3f4);
-  elf_memory_.SetData(0x6238, 0x102030b0);
+  elf_memory_.SetData32(0x5000, 0x1234);
+  elf_memory_.SetData32(0x5004, 0x00001230);
+  elf_memory_.SetData32(0x6234, 0x8201f3f4);
+  elf_memory_.SetData32(0x6238, 0x102030b0);
   ASSERT_TRUE(exidx_->ExtractEntryData(0x5000));
   ASSERT_EQ(6U, data_->size());
   ASSERT_EQ(0xf3, data_->at(0));
@@ -126,12 +126,12 @@
   ASSERT_EQ(0xb0, data_->at(5));
 
   elf_memory_.Clear();
-  elf_memory_.SetData(0x5000, 0x1234);
-  elf_memory_.SetData(0x5004, 0x00001230);
-  elf_memory_.SetData(0x6234, 0x8103f3f4);
-  elf_memory_.SetData(0x6238, 0x10203040);
-  elf_memory_.SetData(0x623c, 0x50607080);
-  elf_memory_.SetData(0x6240, 0x90a0c0d0);
+  elf_memory_.SetData32(0x5000, 0x1234);
+  elf_memory_.SetData32(0x5004, 0x00001230);
+  elf_memory_.SetData32(0x6234, 0x8103f3f4);
+  elf_memory_.SetData32(0x6238, 0x10203040);
+  elf_memory_.SetData32(0x623c, 0x50607080);
+  elf_memory_.SetData32(0x6240, 0x90a0c0d0);
   ASSERT_TRUE(exidx_->ExtractEntryData(0x5000));
   ASSERT_EQ(15U, data_->size());
   ASSERT_EQ(0xf3, data_->at(0));
@@ -152,33 +152,33 @@
 }
 
 TEST_F(ArmExidxExtractTest, second_read_compact_personality_illegal) {
-  elf_memory_.SetData(0x5000, 0x7ffa1e48);
-  elf_memory_.SetData(0x5004, 0x1230);
-  elf_memory_.SetData(0x6234, 0x832132b0);
+  elf_memory_.SetData32(0x5000, 0x7ffa1e48);
+  elf_memory_.SetData32(0x5004, 0x1230);
+  elf_memory_.SetData32(0x6234, 0x832132b0);
   ASSERT_FALSE(exidx_->ExtractEntryData(0x5000));
   ASSERT_EQ(ARM_STATUS_INVALID_PERSONALITY, exidx_->status());
 
   elf_memory_.Clear();
-  elf_memory_.SetData(0x5000, 0x7ffa1e48);
-  elf_memory_.SetData(0x5004, 0x1230);
-  elf_memory_.SetData(0x6234, 0x842132b0);
+  elf_memory_.SetData32(0x5000, 0x7ffa1e48);
+  elf_memory_.SetData32(0x5004, 0x1230);
+  elf_memory_.SetData32(0x6234, 0x842132b0);
   ASSERT_FALSE(exidx_->ExtractEntryData(0x5000));
   ASSERT_EQ(ARM_STATUS_INVALID_PERSONALITY, exidx_->status());
 }
 
 TEST_F(ArmExidxExtractTest, second_read_offset_is_negative) {
-  elf_memory_.SetData(0x5000, 0x7ffa1e48);
-  elf_memory_.SetData(0x5004, 0x7fffb1e0);
-  elf_memory_.SetData(0x1e4, 0x842132b0);
+  elf_memory_.SetData32(0x5000, 0x7ffa1e48);
+  elf_memory_.SetData32(0x5004, 0x7fffb1e0);
+  elf_memory_.SetData32(0x1e4, 0x842132b0);
   ASSERT_FALSE(exidx_->ExtractEntryData(0x5000));
   ASSERT_EQ(ARM_STATUS_INVALID_PERSONALITY, exidx_->status());
 }
 
 TEST_F(ArmExidxExtractTest, second_read_not_compact) {
-  elf_memory_.SetData(0x5000, 0x1234);
-  elf_memory_.SetData(0x5004, 0x00001230);
-  elf_memory_.SetData(0x6234, 0x1);
-  elf_memory_.SetData(0x6238, 0x001122b0);
+  elf_memory_.SetData32(0x5000, 0x1234);
+  elf_memory_.SetData32(0x5004, 0x00001230);
+  elf_memory_.SetData32(0x6234, 0x1);
+  elf_memory_.SetData32(0x6238, 0x001122b0);
   ASSERT_TRUE(exidx_->ExtractEntryData(0x5000));
   ASSERT_EQ(3U, data_->size());
   ASSERT_EQ(0x11, data_->at(0));
@@ -186,10 +186,10 @@
   ASSERT_EQ(0xb0, data_->at(2));
 
   elf_memory_.Clear();
-  elf_memory_.SetData(0x5000, 0x1234);
-  elf_memory_.SetData(0x5004, 0x00001230);
-  elf_memory_.SetData(0x6234, 0x2);
-  elf_memory_.SetData(0x6238, 0x00112233);
+  elf_memory_.SetData32(0x5000, 0x1234);
+  elf_memory_.SetData32(0x5004, 0x00001230);
+  elf_memory_.SetData32(0x6234, 0x2);
+  elf_memory_.SetData32(0x6238, 0x00112233);
   ASSERT_TRUE(exidx_->ExtractEntryData(0x5000));
   ASSERT_EQ(4U, data_->size());
   ASSERT_EQ(0x11, data_->at(0));
@@ -198,11 +198,11 @@
   ASSERT_EQ(0xb0, data_->at(3));
 
   elf_memory_.Clear();
-  elf_memory_.SetData(0x5000, 0x1234);
-  elf_memory_.SetData(0x5004, 0x00001230);
-  elf_memory_.SetData(0x6234, 0x3);
-  elf_memory_.SetData(0x6238, 0x01112233);
-  elf_memory_.SetData(0x623c, 0x445566b0);
+  elf_memory_.SetData32(0x5000, 0x1234);
+  elf_memory_.SetData32(0x5004, 0x00001230);
+  elf_memory_.SetData32(0x6234, 0x3);
+  elf_memory_.SetData32(0x6238, 0x01112233);
+  elf_memory_.SetData32(0x623c, 0x445566b0);
   ASSERT_TRUE(exidx_->ExtractEntryData(0x5000));
   ASSERT_EQ(7U, data_->size());
   ASSERT_EQ(0x11, data_->at(0));
@@ -214,15 +214,15 @@
   ASSERT_EQ(0xb0, data_->at(6));
 
   elf_memory_.Clear();
-  elf_memory_.SetData(0x5000, 0x1234);
-  elf_memory_.SetData(0x5004, 0x00001230);
-  elf_memory_.SetData(0x6234, 0x3);
-  elf_memory_.SetData(0x6238, 0x05112233);
-  elf_memory_.SetData(0x623c, 0x01020304);
-  elf_memory_.SetData(0x6240, 0x05060708);
-  elf_memory_.SetData(0x6244, 0x090a0b0c);
-  elf_memory_.SetData(0x6248, 0x0d0e0f10);
-  elf_memory_.SetData(0x624c, 0x11121314);
+  elf_memory_.SetData32(0x5000, 0x1234);
+  elf_memory_.SetData32(0x5004, 0x00001230);
+  elf_memory_.SetData32(0x6234, 0x3);
+  elf_memory_.SetData32(0x6238, 0x05112233);
+  elf_memory_.SetData32(0x623c, 0x01020304);
+  elf_memory_.SetData32(0x6240, 0x05060708);
+  elf_memory_.SetData32(0x6244, 0x090a0b0c);
+  elf_memory_.SetData32(0x6248, 0x0d0e0f10);
+  elf_memory_.SetData32(0x624c, 0x11121314);
   ASSERT_TRUE(exidx_->ExtractEntryData(0x5000));
   ASSERT_EQ(24U, data_->size());
   ASSERT_EQ(0x11, data_->at(0));
@@ -255,43 +255,43 @@
   ASSERT_FALSE(exidx_->ExtractEntryData(0x5000));
   ASSERT_EQ(ARM_STATUS_READ_FAILED, exidx_->status());
 
-  elf_memory_.SetData(0x5000, 0x100);
+  elf_memory_.SetData32(0x5000, 0x100);
   ASSERT_FALSE(exidx_->ExtractEntryData(0x5000));
   ASSERT_EQ(ARM_STATUS_READ_FAILED, exidx_->status());
 
-  elf_memory_.SetData(0x5004, 0x100);
+  elf_memory_.SetData32(0x5004, 0x100);
   ASSERT_FALSE(exidx_->ExtractEntryData(0x5000));
   ASSERT_EQ(ARM_STATUS_READ_FAILED, exidx_->status());
 
-  elf_memory_.SetData(0x5104, 0x1);
+  elf_memory_.SetData32(0x5104, 0x1);
   ASSERT_FALSE(exidx_->ExtractEntryData(0x5000));
   ASSERT_EQ(ARM_STATUS_READ_FAILED, exidx_->status());
 
-  elf_memory_.SetData(0x5108, 0x01010203);
+  elf_memory_.SetData32(0x5108, 0x01010203);
   ASSERT_FALSE(exidx_->ExtractEntryData(0x5000));
   ASSERT_EQ(ARM_STATUS_READ_FAILED, exidx_->status());
 }
 
 TEST_F(ArmExidxExtractTest, malformed) {
-  elf_memory_.SetData(0x5000, 0x100);
-  elf_memory_.SetData(0x5004, 0x100);
-  elf_memory_.SetData(0x5104, 0x1);
-  elf_memory_.SetData(0x5108, 0x06010203);
+  elf_memory_.SetData32(0x5000, 0x100);
+  elf_memory_.SetData32(0x5004, 0x100);
+  elf_memory_.SetData32(0x5104, 0x1);
+  elf_memory_.SetData32(0x5108, 0x06010203);
   ASSERT_FALSE(exidx_->ExtractEntryData(0x5000));
   ASSERT_EQ(ARM_STATUS_MALFORMED, exidx_->status());
 
   elf_memory_.Clear();
-  elf_memory_.SetData(0x5000, 0x100);
-  elf_memory_.SetData(0x5004, 0x100);
-  elf_memory_.SetData(0x5104, 0x1);
-  elf_memory_.SetData(0x5108, 0x81060203);
+  elf_memory_.SetData32(0x5000, 0x100);
+  elf_memory_.SetData32(0x5004, 0x100);
+  elf_memory_.SetData32(0x5104, 0x1);
+  elf_memory_.SetData32(0x5108, 0x81060203);
   ASSERT_FALSE(exidx_->ExtractEntryData(0x5000));
   ASSERT_EQ(ARM_STATUS_MALFORMED, exidx_->status());
 }
 
 TEST_F(ArmExidxExtractTest, cant_unwind_log) {
-  elf_memory_.SetData(0x1000, 0x7fff2340);
-  elf_memory_.SetData(0x1004, 1);
+  elf_memory_.SetData32(0x1000, 0x7fff2340);
+  elf_memory_.SetData32(0x1004, 1);
 
   exidx_->set_log(true);
   exidx_->set_log_indent(0);
@@ -305,8 +305,8 @@
 }
 
 TEST_F(ArmExidxExtractTest, raw_data_compact) {
-  elf_memory_.SetData(0x4000, 0x7ffa3000);
-  elf_memory_.SetData(0x4004, 0x80a8b0b0);
+  elf_memory_.SetData32(0x4000, 0x7ffa3000);
+  elf_memory_.SetData32(0x4004, 0x80a8b0b0);
 
   exidx_->set_log(true);
   exidx_->set_log_indent(0);
@@ -317,10 +317,10 @@
 }
 
 TEST_F(ArmExidxExtractTest, raw_data_non_compact) {
-  elf_memory_.SetData(0x5000, 0x1234);
-  elf_memory_.SetData(0x5004, 0x00001230);
-  elf_memory_.SetData(0x6234, 0x2);
-  elf_memory_.SetData(0x6238, 0x00112233);
+  elf_memory_.SetData32(0x5000, 0x1234);
+  elf_memory_.SetData32(0x5004, 0x00001230);
+  elf_memory_.SetData32(0x6234, 0x2);
+  elf_memory_.SetData32(0x6238, 0x00112233);
 
   exidx_->set_log(true);
   exidx_->set_log_indent(0);
diff --git a/libunwindstack/tests/ElfInterfaceArmTest.cpp b/libunwindstack/tests/ElfInterfaceArmTest.cpp
new file mode 100644
index 0000000..67c9a6b
--- /dev/null
+++ b/libunwindstack/tests/ElfInterfaceArmTest.cpp
@@ -0,0 +1,372 @@
+/*
+ * Copyright (C) 2016 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 <elf.h>
+
+#include <gtest/gtest.h>
+
+#include <vector>
+
+#include "ElfInterfaceArm.h"
+#include "Machine.h"
+#include "Regs.h"
+
+#include "MemoryFake.h"
+
+class ElfInterfaceArmTest : public ::testing::Test {
+ protected:
+  void SetUp() override {
+    memory_.Clear();
+    process_memory_.Clear();
+  }
+
+  MemoryFake memory_;
+  MemoryFake process_memory_;
+};
+
+TEST_F(ElfInterfaceArmTest, GetPrel32Addr) {
+  ElfInterfaceArm interface(&memory_);
+  memory_.SetData32(0x1000, 0x230000);
+
+  uint32_t value;
+  ASSERT_TRUE(interface.GetPrel31Addr(0x1000, &value));
+  ASSERT_EQ(0x231000U, value);
+
+  memory_.SetData32(0x1000, 0x80001000);
+  ASSERT_TRUE(interface.GetPrel31Addr(0x1000, &value));
+  ASSERT_EQ(0x2000U, value);
+
+  memory_.SetData32(0x1000, 0x70001000);
+  ASSERT_TRUE(interface.GetPrel31Addr(0x1000, &value));
+  ASSERT_EQ(0xf0002000U, value);
+}
+
+TEST_F(ElfInterfaceArmTest, FindEntry_start_zero) {
+  ElfInterfaceArm interface(&memory_);
+  interface.set_start_offset(0);
+  interface.set_total_entries(10);
+
+  uint64_t entry_offset;
+  ASSERT_FALSE(interface.FindEntry(0x1000, &entry_offset));
+}
+
+TEST_F(ElfInterfaceArmTest, FindEntry_no_entries) {
+  ElfInterfaceArm interface(&memory_);
+  interface.set_start_offset(0x100);
+  interface.set_total_entries(0);
+
+  uint64_t entry_offset;
+  ASSERT_FALSE(interface.FindEntry(0x1000, &entry_offset));
+}
+
+TEST_F(ElfInterfaceArmTest, FindEntry_no_valid_memory) {
+  ElfInterfaceArm interface(&memory_);
+  interface.set_start_offset(0x100);
+  interface.set_total_entries(2);
+
+  uint64_t entry_offset;
+  ASSERT_FALSE(interface.FindEntry(0x1000, &entry_offset));
+}
+
+TEST_F(ElfInterfaceArmTest, FindEntry_ip_before_first) {
+  ElfInterfaceArm interface(&memory_);
+  interface.set_start_offset(0x1000);
+  interface.set_total_entries(1);
+  memory_.SetData32(0x1000, 0x6000);
+
+  uint64_t entry_offset;
+  ASSERT_FALSE(interface.FindEntry(0x1000, &entry_offset));
+}
+
+TEST_F(ElfInterfaceArmTest, FindEntry_single_entry_negative_value) {
+  ElfInterfaceArm interface(&memory_);
+  interface.set_start_offset(0x8000);
+  interface.set_total_entries(1);
+  memory_.SetData32(0x8000, 0x7fffff00);
+
+  uint64_t entry_offset;
+  ASSERT_TRUE(interface.FindEntry(0x7ff0, &entry_offset));
+  ASSERT_EQ(0x8000U, entry_offset);
+}
+
+TEST_F(ElfInterfaceArmTest, FindEntry_two_entries) {
+  ElfInterfaceArm interface(&memory_);
+  interface.set_start_offset(0x1000);
+  interface.set_total_entries(2);
+  memory_.SetData32(0x1000, 0x6000);
+  memory_.SetData32(0x1008, 0x7000);
+
+  uint64_t entry_offset;
+  ASSERT_TRUE(interface.FindEntry(0x7000, &entry_offset));
+  ASSERT_EQ(0x1000U, entry_offset);
+}
+
+
+TEST_F(ElfInterfaceArmTest, FindEntry_last_check_single_entry) {
+  ElfInterfaceArm interface(&memory_);
+  interface.set_start_offset(0x1000);
+  interface.set_total_entries(1);
+  memory_.SetData32(0x1000, 0x6000);
+
+  uint64_t entry_offset;
+  ASSERT_TRUE(interface.FindEntry(0x7000, &entry_offset));
+  ASSERT_EQ(0x1000U, entry_offset);
+
+  // To guarantee that we are using the cache on the second run,
+  // set the memory to a different value.
+  memory_.SetData32(0x1000, 0x8000);
+  ASSERT_TRUE(interface.FindEntry(0x7004, &entry_offset));
+  ASSERT_EQ(0x1000U, entry_offset);
+}
+
+TEST_F(ElfInterfaceArmTest, FindEntry_last_check_multiple_entries) {
+  ElfInterfaceArm interface(&memory_);
+  interface.set_start_offset(0x1000);
+  interface.set_total_entries(2);
+  memory_.SetData32(0x1000, 0x6000);
+  memory_.SetData32(0x1008, 0x8000);
+
+  uint64_t entry_offset;
+  ASSERT_TRUE(interface.FindEntry(0x9008, &entry_offset));
+  ASSERT_EQ(0x1008U, entry_offset);
+
+  // To guarantee that we are using the cache on the second run,
+  // set the memory to a different value.
+  memory_.SetData32(0x1000, 0x16000);
+  memory_.SetData32(0x1008, 0x18000);
+  ASSERT_TRUE(interface.FindEntry(0x9100, &entry_offset));
+  ASSERT_EQ(0x1008U, entry_offset);
+}
+
+TEST_F(ElfInterfaceArmTest, FindEntry_multiple_entries_even) {
+  ElfInterfaceArm interface(&memory_);
+  interface.set_start_offset(0x1000);
+  interface.set_total_entries(4);
+  memory_.SetData32(0x1000, 0x6000);
+  memory_.SetData32(0x1008, 0x7000);
+  memory_.SetData32(0x1010, 0x8000);
+  memory_.SetData32(0x1018, 0x9000);
+
+  uint64_t entry_offset;
+  ASSERT_TRUE(interface.FindEntry(0x9100, &entry_offset));
+  ASSERT_EQ(0x1010U, entry_offset);
+
+  // To guarantee that we are using the cache on the second run,
+  // set the memory to a different value.
+  memory_.SetData32(0x1000, 0x16000);
+  memory_.SetData32(0x1008, 0x17000);
+  memory_.SetData32(0x1010, 0x18000);
+  memory_.SetData32(0x1018, 0x19000);
+  ASSERT_TRUE(interface.FindEntry(0x9100, &entry_offset));
+  ASSERT_EQ(0x1010U, entry_offset);
+}
+
+TEST_F(ElfInterfaceArmTest, FindEntry_multiple_entries_odd) {
+  ElfInterfaceArm interface(&memory_);
+  interface.set_start_offset(0x1000);
+  interface.set_total_entries(5);
+  memory_.SetData32(0x1000, 0x5000);
+  memory_.SetData32(0x1008, 0x6000);
+  memory_.SetData32(0x1010, 0x7000);
+  memory_.SetData32(0x1018, 0x8000);
+  memory_.SetData32(0x1020, 0x9000);
+
+  uint64_t entry_offset;
+  ASSERT_TRUE(interface.FindEntry(0x8100, &entry_offset));
+  ASSERT_EQ(0x1010U, entry_offset);
+
+  // To guarantee that we are using the cache on the second run,
+  // set the memory to a different value.
+  memory_.SetData32(0x1000, 0x15000);
+  memory_.SetData32(0x1008, 0x16000);
+  memory_.SetData32(0x1010, 0x17000);
+  memory_.SetData32(0x1018, 0x18000);
+  memory_.SetData32(0x1020, 0x19000);
+  ASSERT_TRUE(interface.FindEntry(0x8100, &entry_offset));
+  ASSERT_EQ(0x1010U, entry_offset);
+}
+
+TEST_F(ElfInterfaceArmTest, iterate) {
+  ElfInterfaceArm interface(&memory_);
+  interface.set_start_offset(0x1000);
+  interface.set_total_entries(5);
+  memory_.SetData32(0x1000, 0x5000);
+  memory_.SetData32(0x1008, 0x6000);
+  memory_.SetData32(0x1010, 0x7000);
+  memory_.SetData32(0x1018, 0x8000);
+  memory_.SetData32(0x1020, 0x9000);
+
+  std::vector<uint32_t> entries;
+  for (auto addr : interface) {
+    entries.push_back(addr);
+  }
+  ASSERT_EQ(5U, entries.size());
+  ASSERT_EQ(0x6000U, entries[0]);
+  ASSERT_EQ(0x7008U, entries[1]);
+  ASSERT_EQ(0x8010U, entries[2]);
+  ASSERT_EQ(0x9018U, entries[3]);
+  ASSERT_EQ(0xa020U, entries[4]);
+
+  // Make sure the iterate cached the entries.
+  memory_.SetData32(0x1000, 0x11000);
+  memory_.SetData32(0x1008, 0x12000);
+  memory_.SetData32(0x1010, 0x13000);
+  memory_.SetData32(0x1018, 0x14000);
+  memory_.SetData32(0x1020, 0x15000);
+
+  entries.clear();
+  for (auto addr : interface) {
+    entries.push_back(addr);
+  }
+  ASSERT_EQ(5U, entries.size());
+  ASSERT_EQ(0x6000U, entries[0]);
+  ASSERT_EQ(0x7008U, entries[1]);
+  ASSERT_EQ(0x8010U, entries[2]);
+  ASSERT_EQ(0x9018U, entries[3]);
+  ASSERT_EQ(0xa020U, entries[4]);
+}
+
+TEST_F(ElfInterfaceArmTest, FindEntry_load_bias) {
+  ElfInterfaceArm interface(&memory_);
+  interface.set_start_offset(0x1000);
+  interface.set_total_entries(2);
+  memory_.SetData32(0x1000, 0x6000);
+  memory_.SetData32(0x1008, 0x8000);
+
+  uint64_t entry_offset;
+  interface.set_load_bias(0x2000);
+  ASSERT_FALSE(interface.FindEntry(0x1000, &entry_offset));
+  ASSERT_FALSE(interface.FindEntry(0x8000, &entry_offset));
+  ASSERT_FALSE(interface.FindEntry(0x8fff, &entry_offset));
+  ASSERT_TRUE(interface.FindEntry(0x9000, &entry_offset));
+  ASSERT_EQ(0x1000U, entry_offset);
+  ASSERT_TRUE(interface.FindEntry(0xb007, &entry_offset));
+  ASSERT_EQ(0x1000U, entry_offset);
+  ASSERT_TRUE(interface.FindEntry(0xb008, &entry_offset));
+  ASSERT_EQ(0x1008U, entry_offset);
+}
+
+TEST_F(ElfInterfaceArmTest, HandleType_not_arm_exidx) {
+  ElfInterfaceArm interface(&memory_);
+
+  ASSERT_FALSE(interface.HandleType(0x1000, PT_NULL));
+  ASSERT_FALSE(interface.HandleType(0x1000, PT_LOAD));
+  ASSERT_FALSE(interface.HandleType(0x1000, PT_DYNAMIC));
+  ASSERT_FALSE(interface.HandleType(0x1000, PT_INTERP));
+  ASSERT_FALSE(interface.HandleType(0x1000, PT_NOTE));
+  ASSERT_FALSE(interface.HandleType(0x1000, PT_SHLIB));
+  ASSERT_FALSE(interface.HandleType(0x1000, PT_PHDR));
+  ASSERT_FALSE(interface.HandleType(0x1000, PT_TLS));
+  ASSERT_FALSE(interface.HandleType(0x1000, PT_LOOS));
+  ASSERT_FALSE(interface.HandleType(0x1000, PT_HIOS));
+  ASSERT_FALSE(interface.HandleType(0x1000, PT_LOPROC));
+  ASSERT_FALSE(interface.HandleType(0x1000, PT_HIPROC));
+  ASSERT_FALSE(interface.HandleType(0x1000, PT_GNU_EH_FRAME));
+  ASSERT_FALSE(interface.HandleType(0x1000, PT_GNU_STACK));
+}
+
+TEST_F(ElfInterfaceArmTest, HandleType_arm_exidx) {
+  ElfInterfaceArm interface(&memory_);
+
+  Elf32_Phdr phdr;
+  interface.set_start_offset(0x1000);
+  interface.set_total_entries(100);
+  phdr.p_vaddr = 0x2000;
+  phdr.p_memsz = 0xa00;
+
+  // Verify that if reads fail, we don't set the values but still get true.
+  ASSERT_TRUE(interface.HandleType(0x1000, 0x70000001));
+  ASSERT_EQ(0x1000U, interface.start_offset());
+  ASSERT_EQ(100U, interface.total_entries());
+
+  // Verify that if the second read fails, we still don't set the values.
+  memory_.SetData32(
+      0x1000 + reinterpret_cast<uint64_t>(&phdr.p_vaddr) - reinterpret_cast<uint64_t>(&phdr),
+      phdr.p_vaddr);
+  ASSERT_TRUE(interface.HandleType(0x1000, 0x70000001));
+  ASSERT_EQ(0x1000U, interface.start_offset());
+  ASSERT_EQ(100U, interface.total_entries());
+
+  // Everything is correct and present.
+  memory_.SetData32(
+      0x1000 + reinterpret_cast<uint64_t>(&phdr.p_memsz) - reinterpret_cast<uint64_t>(&phdr),
+      phdr.p_memsz);
+  ASSERT_TRUE(interface.HandleType(0x1000, 0x70000001));
+  ASSERT_EQ(0x2000U, interface.start_offset());
+  ASSERT_EQ(320U, interface.total_entries());
+
+  // Non-zero load bias.
+  interface.set_load_bias(0x1000);
+  ASSERT_TRUE(interface.HandleType(0x1000, 0x70000001));
+  ASSERT_EQ(0x1000U, interface.start_offset());
+  ASSERT_EQ(320U, interface.total_entries());
+}
+
+TEST_F(ElfInterfaceArmTest, StepExidx) {
+  ElfInterfaceArm interface(&memory_);
+
+  // FindEntry fails.
+  ASSERT_FALSE(interface.StepExidx(0x7000, nullptr, nullptr));
+
+  // ExtractEntry should fail.
+  interface.set_start_offset(0x1000);
+  interface.set_total_entries(2);
+  memory_.SetData32(0x1000, 0x6000);
+  memory_.SetData32(0x1008, 0x8000);
+
+  RegsArm regs;
+  regs[ARM_REG_SP] = 0x1000;
+  regs[ARM_REG_LR] = 0x20000;
+  regs.set_sp(regs[ARM_REG_SP]);
+  regs.set_pc(0x1234);
+  ASSERT_FALSE(interface.StepExidx(0x7000, &regs, &process_memory_));
+
+  // Eval should fail.
+  memory_.SetData32(0x1004, 0x81000000);
+  ASSERT_FALSE(interface.StepExidx(0x7000, &regs, &process_memory_));
+
+  // Everything should pass.
+  memory_.SetData32(0x1004, 0x80b0b0b0);
+  ASSERT_TRUE(interface.StepExidx(0x7000, &regs, &process_memory_));
+  ASSERT_EQ(0x1000U, regs.sp());
+  ASSERT_EQ(0x1000U, regs[ARM_REG_SP]);
+  ASSERT_EQ(0x20000U, regs.pc());
+  ASSERT_EQ(0x20000U, regs[ARM_REG_PC]);
+}
+
+TEST_F(ElfInterfaceArmTest, StepExidx_pc_set) {
+  ElfInterfaceArm interface(&memory_);
+
+  interface.set_start_offset(0x1000);
+  interface.set_total_entries(2);
+  memory_.SetData32(0x1000, 0x6000);
+  memory_.SetData32(0x1004, 0x808800b0);
+  memory_.SetData32(0x1008, 0x8000);
+  process_memory_.SetData32(0x10000, 0x10);
+
+  RegsArm regs;
+  regs[ARM_REG_SP] = 0x10000;
+  regs[ARM_REG_LR] = 0x20000;
+  regs.set_sp(regs[ARM_REG_SP]);
+  regs.set_pc(0x1234);
+
+  // Everything should pass.
+  ASSERT_TRUE(interface.StepExidx(0x7000, &regs, &process_memory_));
+  ASSERT_EQ(0x10004U, regs.sp());
+  ASSERT_EQ(0x10004U, regs[ARM_REG_SP]);
+  ASSERT_EQ(0x10U, regs.pc());
+  ASSERT_EQ(0x10U, regs[ARM_REG_PC]);
+}
diff --git a/libunwindstack/tests/ElfInterfaceTest.cpp b/libunwindstack/tests/ElfInterfaceTest.cpp
new file mode 100644
index 0000000..c31903d
--- /dev/null
+++ b/libunwindstack/tests/ElfInterfaceTest.cpp
@@ -0,0 +1,573 @@
+/*
+ * Copyright (C) 2016 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 <elf.h>
+
+#include <memory>
+
+#include <gtest/gtest.h>
+
+#include "ElfInterface.h"
+#include "ElfInterfaceArm.h"
+
+#include "MemoryFake.h"
+
+#if !defined(PT_ARM_EXIDX)
+#define PT_ARM_EXIDX 0x70000001
+#endif
+
+#if !defined(EM_AARCH64)
+#define EM_AARCH64 183
+#endif
+
+class ElfInterfaceTest : public ::testing::Test {
+ protected:
+  void SetUp() override {
+    memory_.Clear();
+  }
+
+  void SetStringMemory(uint64_t offset, const char* string) {
+    memory_.SetMemory(offset, string, strlen(string) + 1);
+  }
+
+  template <typename Ehdr, typename Phdr, typename Dyn, typename ElfInterfaceType>
+  void SinglePtLoad();
+
+  template <typename Ehdr, typename Phdr, typename Dyn, typename ElfInterfaceType>
+  void MultipleExecutablePtLoads();
+
+  template <typename Ehdr, typename Phdr, typename Dyn, typename ElfInterfaceType>
+  void MultipleExecutablePtLoadsIncrementsNotSizeOfPhdr();
+
+  template <typename Ehdr, typename Phdr, typename Dyn, typename ElfInterfaceType>
+  void NonExecutablePtLoads();
+
+  template <typename Ehdr, typename Phdr, typename Dyn, typename ElfInterfaceType>
+  void ManyPhdrs();
+
+  template <typename Ehdr, typename Phdr, typename Dyn, typename ElfInterfaceType>
+  void Soname();
+
+  template <typename Ehdr, typename Phdr, typename Dyn, typename ElfInterfaceType>
+  void SonameAfterDtNull();
+
+  template <typename Ehdr, typename Phdr, typename Dyn, typename ElfInterfaceType>
+  void SonameSize();
+
+  MemoryFake memory_;
+};
+
+template <typename Ehdr, typename Phdr, typename Dyn, typename ElfInterfaceType>
+void ElfInterfaceTest::SinglePtLoad() {
+  std::unique_ptr<ElfInterface> elf(new ElfInterfaceType(&memory_));
+
+  Ehdr ehdr;
+  memset(&ehdr, 0, sizeof(ehdr));
+  ehdr.e_phoff = 0x100;
+  ehdr.e_phnum = 1;
+  ehdr.e_phentsize = sizeof(Phdr);
+  memory_.SetMemory(0, &ehdr, sizeof(ehdr));
+
+  Phdr phdr;
+  memset(&phdr, 0, sizeof(phdr));
+  phdr.p_type = PT_LOAD;
+  phdr.p_vaddr = 0x2000;
+  phdr.p_memsz = 0x10000;
+  phdr.p_flags = PF_R | PF_X;
+  phdr.p_align = 0x1000;
+  memory_.SetMemory(0x100, &phdr, sizeof(phdr));
+
+  ASSERT_TRUE(elf->Init());
+
+  const std::unordered_map<uint64_t, LoadInfo>& pt_loads = elf->pt_loads();
+  ASSERT_EQ(1U, pt_loads.size());
+  LoadInfo load_data = pt_loads.at(0);
+  ASSERT_EQ(0U, load_data.offset);
+  ASSERT_EQ(0x2000U, load_data.table_offset);
+  ASSERT_EQ(0x10000U, load_data.table_size);
+}
+
+TEST_F(ElfInterfaceTest, elf32_single_pt_load) {
+  SinglePtLoad<Elf32_Ehdr, Elf32_Phdr, Elf32_Dyn, ElfInterface32>();
+}
+
+TEST_F(ElfInterfaceTest, elf64_single_pt_load) {
+  SinglePtLoad<Elf64_Ehdr, Elf64_Phdr, Elf64_Dyn, ElfInterface64>();
+}
+
+template <typename Ehdr, typename Phdr, typename Dyn, typename ElfInterfaceType>
+void ElfInterfaceTest::MultipleExecutablePtLoads() {
+  std::unique_ptr<ElfInterface> elf(new ElfInterfaceType(&memory_));
+
+  Ehdr ehdr;
+  memset(&ehdr, 0, sizeof(ehdr));
+  ehdr.e_phoff = 0x100;
+  ehdr.e_phnum = 3;
+  ehdr.e_phentsize = sizeof(Phdr);
+  memory_.SetMemory(0, &ehdr, sizeof(ehdr));
+
+  Phdr phdr;
+  memset(&phdr, 0, sizeof(phdr));
+  phdr.p_type = PT_LOAD;
+  phdr.p_vaddr = 0x2000;
+  phdr.p_memsz = 0x10000;
+  phdr.p_flags = PF_R | PF_X;
+  phdr.p_align = 0x1000;
+  memory_.SetMemory(0x100, &phdr, sizeof(phdr));
+
+  memset(&phdr, 0, sizeof(phdr));
+  phdr.p_type = PT_LOAD;
+  phdr.p_offset = 0x1000;
+  phdr.p_vaddr = 0x2001;
+  phdr.p_memsz = 0x10001;
+  phdr.p_flags = PF_R | PF_X;
+  phdr.p_align = 0x1001;
+  memory_.SetMemory(0x100 + sizeof(phdr), &phdr, sizeof(phdr));
+
+  memset(&phdr, 0, sizeof(phdr));
+  phdr.p_type = PT_LOAD;
+  phdr.p_offset = 0x2000;
+  phdr.p_vaddr = 0x2002;
+  phdr.p_memsz = 0x10002;
+  phdr.p_flags = PF_R | PF_X;
+  phdr.p_align = 0x1002;
+  memory_.SetMemory(0x100 + 2 * sizeof(phdr), &phdr, sizeof(phdr));
+
+  ASSERT_TRUE(elf->Init());
+
+  const std::unordered_map<uint64_t, LoadInfo>& pt_loads = elf->pt_loads();
+  ASSERT_EQ(3U, pt_loads.size());
+
+  LoadInfo load_data = pt_loads.at(0);
+  ASSERT_EQ(0U, load_data.offset);
+  ASSERT_EQ(0x2000U, load_data.table_offset);
+  ASSERT_EQ(0x10000U, load_data.table_size);
+
+  load_data = pt_loads.at(0x1000);
+  ASSERT_EQ(0x1000U, load_data.offset);
+  ASSERT_EQ(0x2001U, load_data.table_offset);
+  ASSERT_EQ(0x10001U, load_data.table_size);
+
+  load_data = pt_loads.at(0x2000);
+  ASSERT_EQ(0x2000U, load_data.offset);
+  ASSERT_EQ(0x2002U, load_data.table_offset);
+  ASSERT_EQ(0x10002U, load_data.table_size);
+}
+
+TEST_F(ElfInterfaceTest, elf32_multiple_executable_pt_loads) {
+  MultipleExecutablePtLoads<Elf32_Ehdr, Elf32_Phdr, Elf32_Dyn, ElfInterface32>();
+}
+
+TEST_F(ElfInterfaceTest, elf64_multiple_executable_pt_loads) {
+  MultipleExecutablePtLoads<Elf64_Ehdr, Elf64_Phdr, Elf64_Dyn, ElfInterface64>();
+}
+
+template <typename Ehdr, typename Phdr, typename Dyn, typename ElfInterfaceType>
+void ElfInterfaceTest::MultipleExecutablePtLoadsIncrementsNotSizeOfPhdr() {
+  std::unique_ptr<ElfInterface> elf(new ElfInterfaceType(&memory_));
+
+  Ehdr ehdr;
+  memset(&ehdr, 0, sizeof(ehdr));
+  ehdr.e_phoff = 0x100;
+  ehdr.e_phnum = 3;
+  ehdr.e_phentsize = sizeof(Phdr) + 100;
+  memory_.SetMemory(0, &ehdr, sizeof(ehdr));
+
+  Phdr phdr;
+  memset(&phdr, 0, sizeof(phdr));
+  phdr.p_type = PT_LOAD;
+  phdr.p_vaddr = 0x2000;
+  phdr.p_memsz = 0x10000;
+  phdr.p_flags = PF_R | PF_X;
+  phdr.p_align = 0x1000;
+  memory_.SetMemory(0x100, &phdr, sizeof(phdr));
+
+  memset(&phdr, 0, sizeof(phdr));
+  phdr.p_type = PT_LOAD;
+  phdr.p_offset = 0x1000;
+  phdr.p_vaddr = 0x2001;
+  phdr.p_memsz = 0x10001;
+  phdr.p_flags = PF_R | PF_X;
+  phdr.p_align = 0x1001;
+  memory_.SetMemory(0x100 + sizeof(phdr) + 100, &phdr, sizeof(phdr));
+
+  memset(&phdr, 0, sizeof(phdr));
+  phdr.p_type = PT_LOAD;
+  phdr.p_offset = 0x2000;
+  phdr.p_vaddr = 0x2002;
+  phdr.p_memsz = 0x10002;
+  phdr.p_flags = PF_R | PF_X;
+  phdr.p_align = 0x1002;
+  memory_.SetMemory(0x100 + 2 * (sizeof(phdr) + 100), &phdr, sizeof(phdr));
+
+  ASSERT_TRUE(elf->Init());
+
+  const std::unordered_map<uint64_t, LoadInfo>& pt_loads = elf->pt_loads();
+  ASSERT_EQ(3U, pt_loads.size());
+
+  LoadInfo load_data = pt_loads.at(0);
+  ASSERT_EQ(0U, load_data.offset);
+  ASSERT_EQ(0x2000U, load_data.table_offset);
+  ASSERT_EQ(0x10000U, load_data.table_size);
+
+  load_data = pt_loads.at(0x1000);
+  ASSERT_EQ(0x1000U, load_data.offset);
+  ASSERT_EQ(0x2001U, load_data.table_offset);
+  ASSERT_EQ(0x10001U, load_data.table_size);
+
+  load_data = pt_loads.at(0x2000);
+  ASSERT_EQ(0x2000U, load_data.offset);
+  ASSERT_EQ(0x2002U, load_data.table_offset);
+  ASSERT_EQ(0x10002U, load_data.table_size);
+}
+
+TEST_F(ElfInterfaceTest, elf32_multiple_executable_pt_loads_increments_not_size_of_phdr) {
+  MultipleExecutablePtLoadsIncrementsNotSizeOfPhdr<Elf32_Ehdr, Elf32_Phdr, Elf32_Dyn,
+                                                   ElfInterface32>();
+}
+
+TEST_F(ElfInterfaceTest, elf64_multiple_executable_pt_loads_increments_not_size_of_phdr) {
+  MultipleExecutablePtLoadsIncrementsNotSizeOfPhdr<Elf64_Ehdr, Elf64_Phdr, Elf64_Dyn,
+                                                   ElfInterface64>();
+}
+
+template <typename Ehdr, typename Phdr, typename Dyn, typename ElfInterfaceType>
+void ElfInterfaceTest::NonExecutablePtLoads() {
+  std::unique_ptr<ElfInterface> elf(new ElfInterfaceType(&memory_));
+
+  Ehdr ehdr;
+  memset(&ehdr, 0, sizeof(ehdr));
+  ehdr.e_phoff = 0x100;
+  ehdr.e_phnum = 3;
+  ehdr.e_phentsize = sizeof(Phdr);
+  memory_.SetMemory(0, &ehdr, sizeof(ehdr));
+
+  Phdr phdr;
+  memset(&phdr, 0, sizeof(phdr));
+  phdr.p_type = PT_LOAD;
+  phdr.p_vaddr = 0x2000;
+  phdr.p_memsz = 0x10000;
+  phdr.p_flags = PF_R;
+  phdr.p_align = 0x1000;
+  memory_.SetMemory(0x100, &phdr, sizeof(phdr));
+
+  memset(&phdr, 0, sizeof(phdr));
+  phdr.p_type = PT_LOAD;
+  phdr.p_offset = 0x1000;
+  phdr.p_vaddr = 0x2001;
+  phdr.p_memsz = 0x10001;
+  phdr.p_flags = PF_R | PF_X;
+  phdr.p_align = 0x1001;
+  memory_.SetMemory(0x100 + sizeof(phdr), &phdr, sizeof(phdr));
+
+  memset(&phdr, 0, sizeof(phdr));
+  phdr.p_type = PT_LOAD;
+  phdr.p_offset = 0x2000;
+  phdr.p_vaddr = 0x2002;
+  phdr.p_memsz = 0x10002;
+  phdr.p_flags = PF_R;
+  phdr.p_align = 0x1002;
+  memory_.SetMemory(0x100 + 2 * sizeof(phdr), &phdr, sizeof(phdr));
+
+  ASSERT_TRUE(elf->Init());
+
+  const std::unordered_map<uint64_t, LoadInfo>& pt_loads = elf->pt_loads();
+  ASSERT_EQ(1U, pt_loads.size());
+
+  LoadInfo load_data = pt_loads.at(0x1000);
+  ASSERT_EQ(0x1000U, load_data.offset);
+  ASSERT_EQ(0x2001U, load_data.table_offset);
+  ASSERT_EQ(0x10001U, load_data.table_size);
+}
+
+TEST_F(ElfInterfaceTest, elf32_non_executable_pt_loads) {
+  NonExecutablePtLoads<Elf32_Ehdr, Elf32_Phdr, Elf32_Dyn, ElfInterface32>();
+}
+
+TEST_F(ElfInterfaceTest, elf64_non_executable_pt_loads) {
+  NonExecutablePtLoads<Elf64_Ehdr, Elf64_Phdr, Elf64_Dyn, ElfInterface64>();
+}
+
+template <typename Ehdr, typename Phdr, typename Dyn, typename ElfInterfaceType>
+void ElfInterfaceTest::ManyPhdrs() {
+  std::unique_ptr<ElfInterface> elf(new ElfInterfaceType(&memory_));
+
+  Ehdr ehdr;
+  memset(&ehdr, 0, sizeof(ehdr));
+  ehdr.e_phoff = 0x100;
+  ehdr.e_phnum = 7;
+  ehdr.e_phentsize = sizeof(Phdr);
+  memory_.SetMemory(0, &ehdr, sizeof(ehdr));
+
+  Phdr phdr;
+  uint64_t phdr_offset = 0x100;
+
+  memset(&phdr, 0, sizeof(phdr));
+  phdr.p_type = PT_LOAD;
+  phdr.p_vaddr = 0x2000;
+  phdr.p_memsz = 0x10000;
+  phdr.p_flags = PF_R | PF_X;
+  phdr.p_align = 0x1000;
+  memory_.SetMemory(phdr_offset, &phdr, sizeof(phdr));
+  phdr_offset += sizeof(phdr);
+
+  memset(&phdr, 0, sizeof(phdr));
+  phdr.p_type = PT_GNU_EH_FRAME;
+  memory_.SetMemory(phdr_offset, &phdr, sizeof(phdr));
+  phdr_offset += sizeof(phdr);
+
+  memset(&phdr, 0, sizeof(phdr));
+  phdr.p_type = PT_DYNAMIC;
+  memory_.SetMemory(phdr_offset, &phdr, sizeof(phdr));
+  phdr_offset += sizeof(phdr);
+
+  memset(&phdr, 0, sizeof(phdr));
+  phdr.p_type = PT_INTERP;
+  memory_.SetMemory(phdr_offset, &phdr, sizeof(phdr));
+  phdr_offset += sizeof(phdr);
+
+  memset(&phdr, 0, sizeof(phdr));
+  phdr.p_type = PT_NOTE;
+  memory_.SetMemory(phdr_offset, &phdr, sizeof(phdr));
+  phdr_offset += sizeof(phdr);
+
+  memset(&phdr, 0, sizeof(phdr));
+  phdr.p_type = PT_SHLIB;
+  memory_.SetMemory(phdr_offset, &phdr, sizeof(phdr));
+  phdr_offset += sizeof(phdr);
+
+  memset(&phdr, 0, sizeof(phdr));
+  phdr.p_type = PT_GNU_EH_FRAME;
+  memory_.SetMemory(phdr_offset, &phdr, sizeof(phdr));
+  phdr_offset += sizeof(phdr);
+
+  ASSERT_TRUE(elf->Init());
+
+  const std::unordered_map<uint64_t, LoadInfo>& pt_loads = elf->pt_loads();
+  ASSERT_EQ(1U, pt_loads.size());
+
+  LoadInfo load_data = pt_loads.at(0);
+  ASSERT_EQ(0U, load_data.offset);
+  ASSERT_EQ(0x2000U, load_data.table_offset);
+  ASSERT_EQ(0x10000U, load_data.table_size);
+}
+
+TEST_F(ElfInterfaceTest, elf32_many_phdrs) {
+  ElfInterfaceTest::ManyPhdrs<Elf32_Ehdr, Elf32_Phdr, Elf32_Dyn, ElfInterface32>();
+}
+
+TEST_F(ElfInterfaceTest, elf64_many_phdrs) {
+  ElfInterfaceTest::ManyPhdrs<Elf64_Ehdr, Elf64_Phdr, Elf64_Dyn, ElfInterface64>();
+}
+
+TEST_F(ElfInterfaceTest, elf32_arm) {
+  ElfInterfaceArm elf_arm(&memory_);
+
+  Elf32_Ehdr ehdr;
+  memset(&ehdr, 0, sizeof(ehdr));
+  ehdr.e_phoff = 0x100;
+  ehdr.e_phnum = 1;
+  ehdr.e_phentsize = sizeof(Elf32_Phdr);
+  memory_.SetMemory(0, &ehdr, sizeof(ehdr));
+
+  Elf32_Phdr phdr;
+  memset(&phdr, 0, sizeof(phdr));
+  phdr.p_type = PT_ARM_EXIDX;
+  phdr.p_vaddr = 0x2000;
+  phdr.p_memsz = 16;
+  memory_.SetMemory(0x100, &phdr, sizeof(phdr));
+
+  // Add arm exidx entries.
+  memory_.SetData32(0x2000, 0x1000);
+  memory_.SetData32(0x2008, 0x1000);
+
+  ASSERT_TRUE(elf_arm.Init());
+
+  std::vector<uint32_t> entries;
+  for (auto addr : elf_arm) {
+    entries.push_back(addr);
+  }
+  ASSERT_EQ(2U, entries.size());
+  ASSERT_EQ(0x3000U, entries[0]);
+  ASSERT_EQ(0x3008U, entries[1]);
+
+  ASSERT_EQ(0x2000U, elf_arm.start_offset());
+  ASSERT_EQ(2U, elf_arm.total_entries());
+}
+
+template <typename Ehdr, typename Phdr, typename Dyn, typename ElfInterfaceType>
+void ElfInterfaceTest::Soname() {
+  std::unique_ptr<ElfInterface> elf(new ElfInterfaceType(&memory_));
+
+  Ehdr ehdr;
+  memset(&ehdr, 0, sizeof(ehdr));
+  ehdr.e_phoff = 0x100;
+  ehdr.e_phnum = 1;
+  ehdr.e_phentsize = sizeof(Phdr);
+  memory_.SetMemory(0, &ehdr, sizeof(ehdr));
+
+  Phdr phdr;
+  memset(&phdr, 0, sizeof(phdr));
+  phdr.p_type = PT_DYNAMIC;
+  phdr.p_offset = 0x2000;
+  phdr.p_memsz = sizeof(Dyn) * 3;
+  memory_.SetMemory(0x100, &phdr, sizeof(phdr));
+
+  uint64_t offset = 0x2000;
+  Dyn dyn;
+
+  dyn.d_tag = DT_STRTAB;
+  dyn.d_un.d_ptr = 0x10000;
+  memory_.SetMemory(offset, &dyn, sizeof(dyn));
+  offset += sizeof(dyn);
+
+  dyn.d_tag = DT_STRSZ;
+  dyn.d_un.d_val = 0x1000;
+  memory_.SetMemory(offset, &dyn, sizeof(dyn));
+  offset += sizeof(dyn);
+
+  dyn.d_tag = DT_SONAME;
+  dyn.d_un.d_val = 0x10;
+  memory_.SetMemory(offset, &dyn, sizeof(dyn));
+  offset += sizeof(dyn);
+
+  dyn.d_tag = DT_NULL;
+  memory_.SetMemory(offset, &dyn, sizeof(dyn));
+
+  SetStringMemory(0x10010, "fake_soname.so");
+
+  ASSERT_TRUE(elf->Init());
+  std::string name;
+  ASSERT_TRUE(elf->GetSoname(&name));
+  ASSERT_STREQ("fake_soname.so", name.c_str());
+}
+
+TEST_F(ElfInterfaceTest, elf32_soname) {
+  Soname<Elf32_Ehdr, Elf32_Phdr, Elf32_Dyn, ElfInterface32>();
+}
+
+TEST_F(ElfInterfaceTest, elf64_soname) {
+  Soname<Elf64_Ehdr, Elf64_Phdr, Elf64_Dyn, ElfInterface64>();
+}
+
+template <typename Ehdr, typename Phdr, typename Dyn, typename ElfInterfaceType>
+void ElfInterfaceTest::SonameAfterDtNull() {
+  std::unique_ptr<ElfInterface> elf(new ElfInterfaceType(&memory_));
+
+  Ehdr ehdr;
+  memset(&ehdr, 0, sizeof(ehdr));
+  ehdr.e_phoff = 0x100;
+  ehdr.e_phnum = 1;
+  ehdr.e_phentsize = sizeof(Phdr);
+  memory_.SetMemory(0, &ehdr, sizeof(ehdr));
+
+  Phdr phdr;
+  memset(&phdr, 0, sizeof(phdr));
+  phdr.p_type = PT_DYNAMIC;
+  phdr.p_offset = 0x2000;
+  phdr.p_memsz = sizeof(Dyn) * 3;
+  memory_.SetMemory(0x100, &phdr, sizeof(phdr));
+
+  Dyn dyn;
+  uint64_t offset = 0x2000;
+
+  dyn.d_tag = DT_STRTAB;
+  dyn.d_un.d_ptr = 0x10000;
+  memory_.SetMemory(offset, &dyn, sizeof(dyn));
+  offset += sizeof(dyn);
+
+  dyn.d_tag = DT_STRSZ;
+  dyn.d_un.d_val = 0x1000;
+  memory_.SetMemory(offset, &dyn, sizeof(dyn));
+  offset += sizeof(dyn);
+
+  dyn.d_tag = DT_NULL;
+  memory_.SetMemory(offset, &dyn, sizeof(dyn));
+  offset += sizeof(dyn);
+
+  dyn.d_tag = DT_SONAME;
+  dyn.d_un.d_val = 0x10;
+  memory_.SetMemory(offset, &dyn, sizeof(dyn));
+  offset += sizeof(dyn);
+
+  SetStringMemory(0x10010, "fake_soname.so");
+
+  ASSERT_TRUE(elf->Init());
+  std::string name;
+  ASSERT_FALSE(elf->GetSoname(&name));
+}
+
+TEST_F(ElfInterfaceTest, elf32_soname_after_dt_null) {
+  SonameAfterDtNull<Elf32_Ehdr, Elf32_Phdr, Elf32_Dyn, ElfInterface32>();
+}
+
+TEST_F(ElfInterfaceTest, elf64_soname_after_dt_null) {
+  SonameAfterDtNull<Elf64_Ehdr, Elf64_Phdr, Elf64_Dyn, ElfInterface64>();
+}
+
+template <typename Ehdr, typename Phdr, typename Dyn, typename ElfInterfaceType>
+void ElfInterfaceTest::SonameSize() {
+  std::unique_ptr<ElfInterface> elf(new ElfInterfaceType(&memory_));
+
+  Ehdr ehdr;
+  memset(&ehdr, 0, sizeof(ehdr));
+  ehdr.e_phoff = 0x100;
+  ehdr.e_phnum = 1;
+  ehdr.e_phentsize = sizeof(Phdr);
+  memory_.SetMemory(0, &ehdr, sizeof(ehdr));
+
+  Phdr phdr;
+  memset(&phdr, 0, sizeof(phdr));
+  phdr.p_type = PT_DYNAMIC;
+  phdr.p_offset = 0x2000;
+  phdr.p_memsz = sizeof(Dyn);
+  memory_.SetMemory(0x100, &phdr, sizeof(phdr));
+
+  Dyn dyn;
+  uint64_t offset = 0x2000;
+
+  dyn.d_tag = DT_STRTAB;
+  dyn.d_un.d_ptr = 0x10000;
+  memory_.SetMemory(offset, &dyn, sizeof(dyn));
+  offset += sizeof(dyn);
+
+  dyn.d_tag = DT_STRSZ;
+  dyn.d_un.d_val = 0x10;
+  memory_.SetMemory(offset, &dyn, sizeof(dyn));
+  offset += sizeof(dyn);
+
+  dyn.d_tag = DT_SONAME;
+  dyn.d_un.d_val = 0x10;
+  memory_.SetMemory(offset, &dyn, sizeof(dyn));
+  offset += sizeof(dyn);
+
+  dyn.d_tag = DT_NULL;
+  memory_.SetMemory(offset, &dyn, sizeof(dyn));
+
+  SetStringMemory(0x10010, "fake_soname.so");
+
+  ASSERT_TRUE(elf->Init());
+  std::string name;
+  ASSERT_FALSE(elf->GetSoname(&name));
+}
+
+TEST_F(ElfInterfaceTest, elf32_soname_size) {
+  SonameSize<Elf32_Ehdr, Elf32_Phdr, Elf32_Dyn, ElfInterface32>();
+}
+
+TEST_F(ElfInterfaceTest, elf64_soname_size) {
+  SonameSize<Elf64_Ehdr, Elf64_Phdr, Elf64_Dyn, ElfInterface64>();
+}
diff --git a/libunwindstack/tests/ElfTest.cpp b/libunwindstack/tests/ElfTest.cpp
new file mode 100644
index 0000000..25fec8e
--- /dev/null
+++ b/libunwindstack/tests/ElfTest.cpp
@@ -0,0 +1,210 @@
+/*
+ * Copyright (C) 2016 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 <elf.h>
+
+#include <gtest/gtest.h>
+
+#include "Elf.h"
+
+#include "MemoryFake.h"
+
+#if !defined(PT_ARM_EXIDX)
+#define PT_ARM_EXIDX 0x70000001
+#endif
+
+#if !defined(EM_AARCH64)
+#define EM_AARCH64 183
+#endif
+
+class ElfTest : public ::testing::Test {
+ protected:
+  void SetUp() override {
+    memory_ = new MemoryFake;
+  }
+
+  template <typename Ehdr>
+  void InitEhdr(Ehdr* ehdr) {
+    memset(ehdr, 0, sizeof(Ehdr));
+    memcpy(&ehdr->e_ident[0], ELFMAG, SELFMAG);
+    ehdr->e_ident[EI_DATA] = ELFDATA2LSB;
+    ehdr->e_ident[EI_VERSION] = EV_CURRENT;
+    ehdr->e_ident[EI_OSABI] = ELFOSABI_SYSV;
+  }
+
+  void InitElf32(uint32_t type) {
+    Elf32_Ehdr ehdr;
+
+    InitEhdr<Elf32_Ehdr>(&ehdr);
+    ehdr.e_ident[EI_CLASS] = ELFCLASS32;
+
+    ehdr.e_type = ET_DYN;
+    ehdr.e_machine = type;
+    ehdr.e_version = EV_CURRENT;
+    ehdr.e_entry = 0;
+    ehdr.e_phoff = 0x100;
+    ehdr.e_shoff = 0;
+    ehdr.e_flags = 0;
+    ehdr.e_ehsize = sizeof(ehdr);
+    ehdr.e_phentsize = sizeof(Elf32_Phdr);
+    ehdr.e_phnum = 1;
+    ehdr.e_shentsize = sizeof(Elf32_Shdr);
+    ehdr.e_shnum = 0;
+    ehdr.e_shstrndx = 0;
+    if (type == EM_ARM) {
+      ehdr.e_flags = 0x5000200;
+      ehdr.e_phnum = 2;
+    }
+    memory_->SetMemory(0, &ehdr, sizeof(ehdr));
+
+    Elf32_Phdr phdr;
+    memset(&phdr, 0, sizeof(phdr));
+    phdr.p_type = PT_LOAD;
+    phdr.p_offset = 0;
+    phdr.p_vaddr = 0;
+    phdr.p_paddr = 0;
+    phdr.p_filesz = 0x10000;
+    phdr.p_memsz = 0x10000;
+    phdr.p_flags = PF_R | PF_X;
+    phdr.p_align = 0x1000;
+    memory_->SetMemory(0x100, &phdr, sizeof(phdr));
+
+    if (type == EM_ARM) {
+      memset(&phdr, 0, sizeof(phdr));
+      phdr.p_type = PT_ARM_EXIDX;
+      phdr.p_offset = 0x30000;
+      phdr.p_vaddr = 0x30000;
+      phdr.p_paddr = 0x30000;
+      phdr.p_filesz = 16;
+      phdr.p_memsz = 16;
+      phdr.p_flags = PF_R;
+      phdr.p_align = 0x4;
+      memory_->SetMemory(0x100 + sizeof(phdr), &phdr, sizeof(phdr));
+    }
+  }
+
+  void InitElf64(uint32_t type) {
+    Elf64_Ehdr ehdr;
+
+    InitEhdr<Elf64_Ehdr>(&ehdr);
+    ehdr.e_ident[EI_CLASS] = ELFCLASS64;
+
+    ehdr.e_type = ET_DYN;
+    ehdr.e_machine = type;
+    ehdr.e_version = EV_CURRENT;
+    ehdr.e_entry = 0;
+    ehdr.e_phoff = 0x100;
+    ehdr.e_shoff = 0;
+    ehdr.e_flags = 0x5000200;
+    ehdr.e_ehsize = sizeof(ehdr);
+    ehdr.e_phentsize = sizeof(Elf64_Phdr);
+    ehdr.e_phnum = 1;
+    ehdr.e_shentsize = sizeof(Elf64_Shdr);
+    ehdr.e_shnum = 0;
+    ehdr.e_shstrndx = 0;
+    memory_->SetMemory(0, &ehdr, sizeof(ehdr));
+
+    Elf64_Phdr phdr;
+    memset(&phdr, 0, sizeof(phdr));
+    phdr.p_type = PT_LOAD;
+    phdr.p_offset = 0;
+    phdr.p_vaddr = 0;
+    phdr.p_paddr = 0;
+    phdr.p_filesz = 0x10000;
+    phdr.p_memsz = 0x10000;
+    phdr.p_flags = PF_R | PF_X;
+    phdr.p_align = 0x1000;
+    memory_->SetMemory(0x100, &phdr, sizeof(phdr));
+  }
+
+  MemoryFake* memory_;
+};
+
+TEST_F(ElfTest, invalid_memory) {
+  Elf elf(memory_);
+
+  ASSERT_FALSE(elf.Init());
+  ASSERT_FALSE(elf.valid());
+}
+
+TEST_F(ElfTest, elf_invalid) {
+  Elf elf(memory_);
+
+  InitElf32(EM_386);
+
+  // Corrupt the ELF signature.
+  memory_->SetData32(0, 0x7f000000);
+
+  ASSERT_FALSE(elf.Init());
+  ASSERT_FALSE(elf.valid());
+  ASSERT_TRUE(elf.interface() == nullptr);
+
+  std::string name;
+  ASSERT_FALSE(elf.GetSoname(&name));
+
+  uint64_t func_offset;
+  ASSERT_FALSE(elf.GetFunctionName(0, &name, &func_offset));
+
+  ASSERT_FALSE(elf.Step(0, nullptr, nullptr));
+}
+
+TEST_F(ElfTest, elf_arm) {
+  Elf elf(memory_);
+
+  InitElf32(EM_ARM);
+
+  ASSERT_TRUE(elf.Init());
+  ASSERT_TRUE(elf.valid());
+  ASSERT_EQ(static_cast<uint32_t>(EM_ARM), elf.machine_type());
+  ASSERT_EQ(ELFCLASS32, elf.class_type());
+  ASSERT_TRUE(elf.interface() != nullptr);
+}
+
+TEST_F(ElfTest, elf_x86) {
+  Elf elf(memory_);
+
+  InitElf32(EM_386);
+
+  ASSERT_TRUE(elf.Init());
+  ASSERT_TRUE(elf.valid());
+  ASSERT_EQ(static_cast<uint32_t>(EM_386), elf.machine_type());
+  ASSERT_EQ(ELFCLASS32, elf.class_type());
+  ASSERT_TRUE(elf.interface() != nullptr);
+}
+
+TEST_F(ElfTest, elf_arm64) {
+  Elf elf(memory_);
+
+  InitElf64(EM_AARCH64);
+
+  ASSERT_TRUE(elf.Init());
+  ASSERT_TRUE(elf.valid());
+  ASSERT_EQ(static_cast<uint32_t>(EM_AARCH64), elf.machine_type());
+  ASSERT_EQ(ELFCLASS64, elf.class_type());
+  ASSERT_TRUE(elf.interface() != nullptr);
+}
+
+TEST_F(ElfTest, elf_x86_64) {
+  Elf elf(memory_);
+
+  InitElf64(EM_X86_64);
+
+  ASSERT_TRUE(elf.Init());
+  ASSERT_TRUE(elf.valid());
+  ASSERT_EQ(static_cast<uint32_t>(EM_X86_64), elf.machine_type());
+  ASSERT_EQ(ELFCLASS64, elf.class_type());
+  ASSERT_TRUE(elf.interface() != nullptr);
+}
diff --git a/libunwindstack/tests/MapsTest.cpp b/libunwindstack/tests/MapsTest.cpp
deleted file mode 100644
index 216873f..0000000
--- a/libunwindstack/tests/MapsTest.cpp
+++ /dev/null
@@ -1,219 +0,0 @@
-/*
- * Copyright (C) 2016 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 <sys/mman.h>
-
-#include <android-base/file.h>
-#include <android-base/test_utils.h>
-#include <gtest/gtest.h>
-
-#include "Maps.h"
-
-#include "LogFake.h"
-
-class MapsTest : public ::testing::Test {
- protected:
-  void SetUp() override {
-    ResetLogs();
-  }
-};
-
-TEST_F(MapsTest, parse_permissions) {
-  MapsBuffer maps("1000-2000 ---- 00000000 00:00 0\n"
-                  "2000-3000 r--- 00000000 00:00 0\n"
-                  "3000-4000 -w-- 00000000 00:00 0\n"
-                  "4000-5000 --x- 00000000 00:00 0\n"
-                  "5000-6000 rwx- 00000000 00:00 0\n");
-
-  ASSERT_TRUE(maps.Parse());
-  ASSERT_EQ(5U, maps.Total());
-  auto it = maps.begin();
-  ASSERT_EQ(PROT_NONE, it->flags);
-  ASSERT_EQ(0x1000U, it->start);
-  ASSERT_EQ(0x2000U, it->end);
-  ASSERT_EQ(0U, it->offset);
-  ASSERT_EQ("", it->name);
-  ++it;
-  ASSERT_EQ(PROT_READ, it->flags);
-  ASSERT_EQ(0x2000U, it->start);
-  ASSERT_EQ(0x3000U, it->end);
-  ASSERT_EQ(0U, it->offset);
-  ASSERT_EQ("", it->name);
-  ++it;
-  ASSERT_EQ(PROT_WRITE, it->flags);
-  ASSERT_EQ(0x3000U, it->start);
-  ASSERT_EQ(0x4000U, it->end);
-  ASSERT_EQ(0U, it->offset);
-  ASSERT_EQ("", it->name);
-  ++it;
-  ASSERT_EQ(PROT_EXEC, it->flags);
-  ASSERT_EQ(0x4000U, it->start);
-  ASSERT_EQ(0x5000U, it->end);
-  ASSERT_EQ(0U, it->offset);
-  ASSERT_EQ("", it->name);
-  ++it;
-  ASSERT_EQ(PROT_READ | PROT_WRITE | PROT_EXEC, it->flags);
-  ASSERT_EQ(0x5000U, it->start);
-  ASSERT_EQ(0x6000U, it->end);
-  ASSERT_EQ(0U, it->offset);
-  ASSERT_EQ("", it->name);
-  ++it;
-  ASSERT_EQ(it, maps.end());
-}
-
-TEST_F(MapsTest, parse_name) {
-  MapsBuffer maps("720b29b000-720b29e000 rw-p 00000000 00:00 0\n"
-                  "720b29e000-720b29f000 rw-p 00000000 00:00 0 /system/lib/fake.so\n"
-                  "720b29f000-720b2a0000 rw-p 00000000 00:00 0");
-
-  ASSERT_TRUE(maps.Parse());
-  ASSERT_EQ(3U, maps.Total());
-  auto it = maps.begin();
-  ASSERT_EQ("", it->name);
-  ASSERT_EQ(0x720b29b000U, it->start);
-  ASSERT_EQ(0x720b29e000U, it->end);
-  ASSERT_EQ(0U, it->offset);
-  ASSERT_EQ(PROT_READ | PROT_WRITE, it->flags);
-  ++it;
-  ASSERT_EQ("/system/lib/fake.so", it->name);
-  ASSERT_EQ(0x720b29e000U, it->start);
-  ASSERT_EQ(0x720b29f000U, it->end);
-  ASSERT_EQ(0U, it->offset);
-  ASSERT_EQ(PROT_READ | PROT_WRITE, it->flags);
-  ++it;
-  ASSERT_EQ("", it->name);
-  ASSERT_EQ(0x720b29f000U, it->start);
-  ASSERT_EQ(0x720b2a0000U, it->end);
-  ASSERT_EQ(0U, it->offset);
-  ASSERT_EQ(PROT_READ | PROT_WRITE, it->flags);
-  ++it;
-  ASSERT_EQ(it, maps.end());
-}
-
-TEST_F(MapsTest, parse_offset) {
-  MapsBuffer maps("a000-e000 rw-p 00000000 00:00 0 /system/lib/fake.so\n"
-                  "e000-f000 rw-p 00a12345 00:00 0 /system/lib/fake.so\n");
-
-  ASSERT_TRUE(maps.Parse());
-  ASSERT_EQ(2U, maps.Total());
-  auto it = maps.begin();
-  ASSERT_EQ(0U, it->offset);
-  ASSERT_EQ(0xa000U, it->start);
-  ASSERT_EQ(0xe000U, it->end);
-  ASSERT_EQ(PROT_READ | PROT_WRITE, it->flags);
-  ASSERT_EQ("/system/lib/fake.so", it->name);
-  ++it;
-  ASSERT_EQ(0xa12345U, it->offset);
-  ASSERT_EQ(0xe000U, it->start);
-  ASSERT_EQ(0xf000U, it->end);
-  ASSERT_EQ(PROT_READ | PROT_WRITE, it->flags);
-  ASSERT_EQ("/system/lib/fake.so", it->name);
-  ++it;
-  ASSERT_EQ(maps.end(), it);
-}
-
-TEST_F(MapsTest, file_smoke) {
-  TemporaryFile tf;
-  ASSERT_TRUE(tf.fd != -1);
-
-  ASSERT_TRUE(android::base::WriteStringToFile(
-      "720b29b000-720b29e000 r-xp a0000000 00:00 0   /fake.so\n"
-      "720b2b0000-720b2e0000 r-xp b0000000 00:00 0   /fake2.so\n"
-      "720b2e0000-720b2f0000 r-xp c0000000 00:00 0   /fake3.so\n",
-      tf.path, 0660, getuid(), getgid()));
-
-  MapsFile maps(tf.path);
-
-  ASSERT_TRUE(maps.Parse());
-  ASSERT_EQ(3U, maps.Total());
-  auto it = maps.begin();
-  ASSERT_EQ(0x720b29b000U, it->start);
-  ASSERT_EQ(0x720b29e000U, it->end);
-  ASSERT_EQ(0xa0000000U, it->offset);
-  ASSERT_EQ(PROT_READ | PROT_EXEC, it->flags);
-  ASSERT_EQ("/fake.so", it->name);
-  ++it;
-  ASSERT_EQ(0x720b2b0000U, it->start);
-  ASSERT_EQ(0x720b2e0000U, it->end);
-  ASSERT_EQ(0xb0000000U, it->offset);
-  ASSERT_EQ(PROT_READ | PROT_EXEC, it->flags);
-  ASSERT_EQ("/fake2.so", it->name);
-  ++it;
-  ASSERT_EQ(0x720b2e0000U, it->start);
-  ASSERT_EQ(0x720b2f0000U, it->end);
-  ASSERT_EQ(0xc0000000U, it->offset);
-  ASSERT_EQ(PROT_READ | PROT_EXEC, it->flags);
-  ASSERT_EQ("/fake3.so", it->name);
-  ++it;
-  ASSERT_EQ(it, maps.end());
-}
-
-TEST_F(MapsTest, find) {
-  MapsBuffer maps("1000-2000 r--p 00000010 00:00 0 /system/lib/fake1.so\n"
-                  "3000-4000 -w-p 00000020 00:00 0 /system/lib/fake2.so\n"
-                  "6000-8000 --xp 00000030 00:00 0 /system/lib/fake3.so\n"
-                  "a000-b000 rw-p 00000040 00:00 0 /system/lib/fake4.so\n"
-                  "e000-f000 rwxp 00000050 00:00 0 /system/lib/fake5.so\n");
-  ASSERT_TRUE(maps.Parse());
-  ASSERT_EQ(5U, maps.Total());
-
-  ASSERT_TRUE(maps.Find(0x500) == nullptr);
-  ASSERT_TRUE(maps.Find(0x2000) == nullptr);
-  ASSERT_TRUE(maps.Find(0x5010) == nullptr);
-  ASSERT_TRUE(maps.Find(0x9a00) == nullptr);
-  ASSERT_TRUE(maps.Find(0xf000) == nullptr);
-  ASSERT_TRUE(maps.Find(0xf010) == nullptr);
-
-  MapInfo* info = maps.Find(0x1000);
-  ASSERT_TRUE(info != nullptr);
-  ASSERT_EQ(0x1000U, info->start);
-  ASSERT_EQ(0x2000U, info->end);
-  ASSERT_EQ(0x10U, info->offset);
-  ASSERT_EQ(PROT_READ, info->flags);
-  ASSERT_EQ("/system/lib/fake1.so", info->name);
-
-  info = maps.Find(0x3020);
-  ASSERT_TRUE(info != nullptr);
-  ASSERT_EQ(0x3000U, info->start);
-  ASSERT_EQ(0x4000U, info->end);
-  ASSERT_EQ(0x20U, info->offset);
-  ASSERT_EQ(PROT_WRITE, info->flags);
-  ASSERT_EQ("/system/lib/fake2.so", info->name);
-
-  info = maps.Find(0x6020);
-  ASSERT_TRUE(info != nullptr);
-  ASSERT_EQ(0x6000U, info->start);
-  ASSERT_EQ(0x8000U, info->end);
-  ASSERT_EQ(0x30U, info->offset);
-  ASSERT_EQ(PROT_EXEC, info->flags);
-  ASSERT_EQ("/system/lib/fake3.so", info->name);
-
-  info = maps.Find(0xafff);
-  ASSERT_TRUE(info != nullptr);
-  ASSERT_EQ(0xa000U, info->start);
-  ASSERT_EQ(0xb000U, info->end);
-  ASSERT_EQ(0x40U, info->offset);
-  ASSERT_EQ(PROT_READ | PROT_WRITE, info->flags);
-  ASSERT_EQ("/system/lib/fake4.so", info->name);
-
-  info = maps.Find(0xe500);
-  ASSERT_TRUE(info != nullptr);
-  ASSERT_EQ(0xe000U, info->start);
-  ASSERT_EQ(0xf000U, info->end);
-  ASSERT_EQ(0x50U, info->offset);
-  ASSERT_EQ(PROT_READ | PROT_WRITE | PROT_EXEC, info->flags);
-  ASSERT_EQ("/system/lib/fake5.so", info->name);
-}
diff --git a/libunwindstack/tests/MemoryFake.h b/libunwindstack/tests/MemoryFake.h
index 4f898fa..e05736b 100644
--- a/libunwindstack/tests/MemoryFake.h
+++ b/libunwindstack/tests/MemoryFake.h
@@ -34,7 +34,19 @@
 
   void SetMemory(uint64_t addr, const void* memory, size_t length);
 
-  void SetData(uint64_t addr, uint32_t value) {
+  void SetData8(uint64_t addr, uint8_t value) {
+    SetMemory(addr, &value, sizeof(value));
+  }
+
+  void SetData16(uint64_t addr, uint16_t value) {
+    SetMemory(addr, &value, sizeof(value));
+  }
+
+  void SetData32(uint64_t addr, uint32_t value) {
+    SetMemory(addr, &value, sizeof(value));
+  }
+
+  void SetData64(uint64_t addr, uint64_t value) {
     SetMemory(addr, &value, sizeof(value));
   }
 
diff --git a/libunwindstack/tests/MemoryFileTest.cpp b/libunwindstack/tests/MemoryFileTest.cpp
index ebc6118..870ca19 100644
--- a/libunwindstack/tests/MemoryFileTest.cpp
+++ b/libunwindstack/tests/MemoryFileTest.cpp
@@ -20,12 +20,9 @@
 
 #include "Memory.h"
 
-#include "LogFake.h"
-
 class MemoryFileTest : public ::testing::Test {
  protected:
   void SetUp() override {
-    ResetLogs();
     tf_ = new TemporaryFile;
   }
 
@@ -86,6 +83,7 @@
     data += static_cast<char>((i % 10) + '0');
   }
   ASSERT_TRUE(android::base::WriteStringToFd(data, tf_->fd));
+
   ASSERT_TRUE(memory_.Init(tf_->path, 2 * pagesize));
   std::vector<char> buffer(11);
   ASSERT_TRUE(memory_.Read(0, buffer.data(), 10));
@@ -106,6 +104,7 @@
     data += static_cast<char>((i % 10) + '0');
   }
   ASSERT_TRUE(android::base::WriteStringToFd(data, tf_->fd));
+
   ASSERT_TRUE(memory_.Init(tf_->path, 2 * pagesize + 10));
   std::vector<char> buffer(11);
   ASSERT_TRUE(memory_.Read(0, buffer.data(), 10));
@@ -165,3 +164,111 @@
   // This should fail because there is no terminating \0
   ASSERT_FALSE(memory_.ReadString(0, &name));
 }
+
+TEST_F(MemoryFileTest, read_past_file_within_mapping) {
+  size_t pagesize = getpagesize();
+
+  ASSERT_TRUE(pagesize > 100);
+  std::vector<uint8_t> buffer(pagesize - 100);
+  for (size_t i = 0; i < pagesize - 100; i++) {
+    buffer[i] = static_cast<uint8_t>((i % 0x5e) + 0x20);
+  }
+  ASSERT_TRUE(android::base::WriteFully(tf_->fd, buffer.data(), buffer.size()));
+
+  ASSERT_TRUE(memory_.Init(tf_->path, 0));
+
+  for (size_t i = 0; i < 100; i++) {
+    uint8_t value;
+    ASSERT_FALSE(memory_.Read(buffer.size() + i, &value, 1)) << "Should have failed at value " << i;
+  }
+}
+
+TEST_F(MemoryFileTest, map_partial_offset_aligned) {
+  size_t pagesize = getpagesize();
+  std::vector<uint8_t> buffer(pagesize * 10);
+  for (size_t i = 0; i < pagesize * 10; i++) {
+    buffer[i] = i / pagesize + 1;
+  }
+  ASSERT_TRUE(android::base::WriteFully(tf_->fd, buffer.data(), buffer.size()));
+
+  // Map in only two pages of the data, and after the first page.
+  ASSERT_TRUE(memory_.Init(tf_->path, pagesize, pagesize * 2));
+
+  std::vector<uint8_t> read_buffer(pagesize * 2);
+  // Make sure that reading after mapped data is a failure.
+  ASSERT_FALSE(memory_.Read(pagesize * 2, read_buffer.data(), 1));
+  ASSERT_TRUE(memory_.Read(0, read_buffer.data(), pagesize * 2));
+  for (size_t i = 0; i < pagesize; i++) {
+    ASSERT_EQ(2, read_buffer[i]) << "Failed at byte " << i;
+  }
+  for (size_t i = pagesize; i < pagesize * 2; i++) {
+    ASSERT_EQ(3, read_buffer[i]) << "Failed at byte " << i;
+  }
+}
+
+TEST_F(MemoryFileTest, map_partial_offset_unaligned) {
+  size_t pagesize = getpagesize();
+  ASSERT_TRUE(pagesize > 0x100);
+  std::vector<uint8_t> buffer(pagesize * 10);
+  for (size_t i = 0; i < buffer.size(); i++) {
+    buffer[i] = i / pagesize + 1;
+  }
+  ASSERT_TRUE(android::base::WriteFully(tf_->fd, buffer.data(), buffer.size()));
+
+  // Map in only two pages of the data, and after the first page.
+  ASSERT_TRUE(memory_.Init(tf_->path, pagesize + 0x100, pagesize * 2));
+
+  std::vector<uint8_t> read_buffer(pagesize * 2);
+  // Make sure that reading after mapped data is a failure.
+  ASSERT_FALSE(memory_.Read(pagesize * 2, read_buffer.data(), 1));
+  ASSERT_TRUE(memory_.Read(0, read_buffer.data(), pagesize * 2));
+  for (size_t i = 0; i < pagesize - 0x100; i++) {
+    ASSERT_EQ(2, read_buffer[i]) << "Failed at byte " << i;
+  }
+  for (size_t i = pagesize - 0x100; i < 2 * pagesize - 0x100; i++) {
+    ASSERT_EQ(3, read_buffer[i]) << "Failed at byte " << i;
+  }
+  for (size_t i = 2 * pagesize - 0x100; i < pagesize * 2; i++) {
+    ASSERT_EQ(4, read_buffer[i]) << "Failed at byte " << i;
+  }
+}
+
+TEST_F(MemoryFileTest, map_overflow) {
+  size_t pagesize = getpagesize();
+  ASSERT_TRUE(pagesize > 0x100);
+  std::vector<uint8_t> buffer(pagesize * 10);
+  for (size_t i = 0; i < buffer.size(); i++) {
+    buffer[i] = i / pagesize + 1;
+  }
+  ASSERT_TRUE(android::base::WriteFully(tf_->fd, buffer.data(), buffer.size()));
+
+  // Map in only two pages of the data, and after the first page.
+  ASSERT_TRUE(memory_.Init(tf_->path, pagesize + 0x100, UINT64_MAX));
+
+  std::vector<uint8_t> read_buffer(pagesize * 10);
+  ASSERT_FALSE(memory_.Read(pagesize * 9 - 0x100 + 1, read_buffer.data(), 1));
+  ASSERT_TRUE(memory_.Read(0, read_buffer.data(), pagesize * 9 - 0x100));
+}
+
+TEST_F(MemoryFileTest, init_reinit) {
+  size_t pagesize = getpagesize();
+  std::vector<uint8_t> buffer(pagesize * 2);
+  for (size_t i = 0; i < buffer.size(); i++) {
+    buffer[i] = i / pagesize + 1;
+  }
+  ASSERT_TRUE(android::base::WriteFully(tf_->fd, buffer.data(), buffer.size()));
+
+  ASSERT_TRUE(memory_.Init(tf_->path, 0));
+  std::vector<uint8_t> read_buffer(buffer.size());
+  ASSERT_TRUE(memory_.Read(0, read_buffer.data(), pagesize));
+  for (size_t i = 0; i < pagesize; i++) {
+    ASSERT_EQ(1, read_buffer[i]) << "Failed at byte " << i;
+  }
+
+  // Now reinit.
+  ASSERT_TRUE(memory_.Init(tf_->path, pagesize));
+  ASSERT_TRUE(memory_.Read(0, read_buffer.data(), pagesize));
+  for (size_t i = 0; i < pagesize; i++) {
+    ASSERT_EQ(2, read_buffer[i]) << "Failed at byte " << i;
+  }
+}
diff --git a/libunwindstack/tests/MemoryLocalTest.cpp b/libunwindstack/tests/MemoryLocalTest.cpp
index 49ece9d..0ba5f1c 100644
--- a/libunwindstack/tests/MemoryLocalTest.cpp
+++ b/libunwindstack/tests/MemoryLocalTest.cpp
@@ -23,16 +23,7 @@
 
 #include "Memory.h"
 
-#include "LogFake.h"
-
-class MemoryLocalTest : public ::testing::Test {
- protected:
-  void SetUp() override {
-    ResetLogs();
-  }
-};
-
-TEST_F(MemoryLocalTest, read) {
+TEST(MemoryLocalTest, read) {
   std::vector<uint8_t> src(1024);
   memset(src.data(), 0x4c, 1024);
 
@@ -56,7 +47,7 @@
   }
 }
 
-TEST_F(MemoryLocalTest, read_string) {
+TEST(MemoryLocalTest, read_string) {
   std::string name("string_in_memory");
 
   MemoryLocal local;
@@ -75,7 +66,7 @@
   ASSERT_FALSE(local.ReadString(reinterpret_cast<uint64_t>(&name[7]), &dst_name, 9));
 }
 
-TEST_F(MemoryLocalTest, read_illegal) {
+TEST(MemoryLocalTest, read_illegal) {
   MemoryLocal local;
 
   std::vector<uint8_t> dst(100);
diff --git a/libunwindstack/tests/MemoryRangeTest.cpp b/libunwindstack/tests/MemoryRangeTest.cpp
index fcae3a4..d636ec4 100644
--- a/libunwindstack/tests/MemoryRangeTest.cpp
+++ b/libunwindstack/tests/MemoryRangeTest.cpp
@@ -23,13 +23,11 @@
 
 #include "Memory.h"
 
-#include "LogFake.h"
 #include "MemoryFake.h"
 
 class MemoryRangeTest : public ::testing::Test {
  protected:
   void SetUp() override {
-    ResetLogs();
     memory_ = new MemoryFake;
   }
 
diff --git a/libunwindstack/tests/MemoryRemoteTest.cpp b/libunwindstack/tests/MemoryRemoteTest.cpp
index 49244a5..7664c3e 100644
--- a/libunwindstack/tests/MemoryRemoteTest.cpp
+++ b/libunwindstack/tests/MemoryRemoteTest.cpp
@@ -33,14 +33,8 @@
 
 #include "Memory.h"
 
-#include "LogFake.h"
-
 class MemoryRemoteTest : public ::testing::Test {
  protected:
-  void SetUp() override {
-    ResetLogs();
-  }
-
   static uint64_t NanoTime() {
     struct timespec t = { 0, 0 };
     clock_gettime(CLOCK_MONOTONIC, &t);
diff --git a/libunwindstack/tests/RegsTest.cpp b/libunwindstack/tests/RegsTest.cpp
index f9e8b0e..0dac278 100644
--- a/libunwindstack/tests/RegsTest.cpp
+++ b/libunwindstack/tests/RegsTest.cpp
@@ -18,50 +18,249 @@
 
 #include <gtest/gtest.h>
 
+#include "Elf.h"
+#include "ElfInterface.h"
+#include "MapInfo.h"
 #include "Regs.h"
 
-class RegsTest : public ::testing::Test {};
+#include "MemoryFake.h"
 
-TEST_F(RegsTest, regs32) {
-  Regs32 regs32(10, 20, 30);
+class ElfFake : public Elf {
+ public:
+  ElfFake(Memory* memory) : Elf(memory) { valid_ = true; }
+  virtual ~ElfFake() = default;
 
-  ASSERT_EQ(10U, regs32.pc_reg());
-  ASSERT_EQ(20U, regs32.sp_reg());
-  ASSERT_EQ(30U, regs32.total_regs());
+  void set_elf_interface(ElfInterface* interface) { interface_.reset(interface); }
+};
 
-  uint32_t* raw = reinterpret_cast<uint32_t*>(regs32.raw_data());
-  for (size_t i = 0; i < 30; i++) {
-    raw[i] = 0xf0000000 + i;
+class ElfInterfaceFake : public ElfInterface {
+ public:
+  ElfInterfaceFake(Memory* memory) : ElfInterface(memory) {}
+  virtual ~ElfInterfaceFake() = default;
+
+  void set_load_bias(uint64_t load_bias) { load_bias_ = load_bias; }
+
+  bool Init() override { return false; }
+  void InitHeaders() override {}
+  bool GetSoname(std::string*) override { return false; }
+  bool GetFunctionName(uint64_t, std::string*, uint64_t*) override { return false; }
+  bool Step(uint64_t, Regs*, Memory*) override { return false; }
+};
+
+template <typename TypeParam>
+class RegsTestTmpl : public RegsTmpl<TypeParam> {
+ public:
+  RegsTestTmpl(uint16_t total_regs, uint16_t regs_sp)
+      : RegsTmpl<TypeParam>(total_regs, regs_sp, Regs::Location(Regs::LOCATION_UNKNOWN, 0)) {}
+  RegsTestTmpl(uint16_t total_regs, uint16_t regs_sp, Regs::Location return_loc)
+      : RegsTmpl<TypeParam>(total_regs, regs_sp, return_loc) {}
+  virtual ~RegsTestTmpl() = default;
+
+  uint64_t GetAdjustedPc(uint64_t, Elf*) { return 0; }
+};
+
+class RegsTest : public ::testing::Test {
+ protected:
+  void SetUp() override {
+    memory_ = new MemoryFake;
+    elf_.reset(new ElfFake(memory_));
+    elf_interface_ = new ElfInterfaceFake(elf_->memory());
+    elf_->set_elf_interface(elf_interface_);
   }
 
-  ASSERT_EQ(0xf000000aU, regs32.pc());
-  ASSERT_EQ(0xf0000014U, regs32.sp());
+  template <typename AddressType>
+  void regs_rel_pc();
 
-  ASSERT_EQ(0xf0000001U, regs32[1]);
-  regs32[1] = 10;
-  ASSERT_EQ(10U, regs32[1]);
+  template <typename AddressType>
+  void regs_return_address_register();
 
-  ASSERT_EQ(0xf000001dU, regs32[29]);
+  ElfInterfaceFake* elf_interface_;
+  MemoryFake* memory_;
+  std::unique_ptr<ElfFake> elf_;
+};
+
+TEST_F(RegsTest, regs32) {
+  RegsTestTmpl<uint32_t> regs32(50, 10);
+  ASSERT_EQ(50U, regs32.total_regs());
+  ASSERT_EQ(10U, regs32.sp_reg());
+
+  uint32_t* raw = reinterpret_cast<uint32_t*>(regs32.RawData());
+  for (size_t i = 0; i < 50; i++) {
+    raw[i] = 0xf0000000 + i;
+  }
+  regs32.set_pc(0xf0120340);
+  regs32.set_sp(0xa0ab0cd0);
+
+  for (size_t i = 0; i < 50; i++) {
+    ASSERT_EQ(0xf0000000U + i, regs32[i]) << "Failed comparing register " << i;
+  }
+
+  ASSERT_EQ(0xf0120340U, regs32.pc());
+  ASSERT_EQ(0xa0ab0cd0U, regs32.sp());
+
+  regs32[32] = 10;
+  ASSERT_EQ(10U, regs32[32]);
 }
 
 TEST_F(RegsTest, regs64) {
-  Regs64 regs64(10, 20, 30);
-
-  ASSERT_EQ(10U, regs64.pc_reg());
-  ASSERT_EQ(20U, regs64.sp_reg());
+  RegsTestTmpl<uint64_t> regs64(30, 12);
   ASSERT_EQ(30U, regs64.total_regs());
+  ASSERT_EQ(12U, regs64.sp_reg());
 
-  uint64_t* raw = reinterpret_cast<uint64_t*>(regs64.raw_data());
+  uint64_t* raw = reinterpret_cast<uint64_t*>(regs64.RawData());
   for (size_t i = 0; i < 30; i++) {
     raw[i] = 0xf123456780000000UL + i;
   }
+  regs64.set_pc(0xf123456780102030UL);
+  regs64.set_sp(0xa123456780a0b0c0UL);
 
-  ASSERT_EQ(0xf12345678000000aUL, regs64.pc());
-  ASSERT_EQ(0xf123456780000014UL, regs64.sp());
+  for (size_t i = 0; i < 30; i++) {
+    ASSERT_EQ(0xf123456780000000U + i, regs64[i]) << "Failed reading register " << i;
+  }
 
-  ASSERT_EQ(0xf123456780000008U, regs64[8]);
+  ASSERT_EQ(0xf123456780102030UL, regs64.pc());
+  ASSERT_EQ(0xa123456780a0b0c0UL, regs64.sp());
+
   regs64[8] = 10;
   ASSERT_EQ(10U, regs64[8]);
+}
 
-  ASSERT_EQ(0xf12345678000001dU, regs64[29]);
+template <typename AddressType>
+void RegsTest::regs_rel_pc() {
+  RegsTestTmpl<AddressType> regs(30, 12);
+
+  elf_interface_->set_load_bias(0);
+  MapInfo map_info{.start = 0x1000, .end = 0x2000};
+  regs.set_pc(0x1101);
+  ASSERT_EQ(0x101U, regs.GetRelPc(elf_.get(), &map_info));
+  elf_interface_->set_load_bias(0x3000);
+  ASSERT_EQ(0x3101U, regs.GetRelPc(elf_.get(), &map_info));
+}
+
+TEST_F(RegsTest, regs32_rel_pc) {
+  regs_rel_pc<uint32_t>();
+}
+
+TEST_F(RegsTest, regs64_rel_pc) {
+  regs_rel_pc<uint64_t>();
+}
+
+template <typename AddressType>
+void RegsTest::regs_return_address_register() {
+  RegsTestTmpl<AddressType> regs(20, 10, Regs::Location(Regs::LOCATION_REGISTER, 5));
+
+  regs[5] = 0x12345;
+  uint64_t value;
+  ASSERT_TRUE(regs.GetReturnAddressFromDefault(memory_, &value));
+  ASSERT_EQ(0x12345U, value);
+}
+
+TEST_F(RegsTest, regs32_return_address_register) {
+  regs_return_address_register<uint32_t>();
+}
+
+TEST_F(RegsTest, regs64_return_address_register) {
+  regs_return_address_register<uint64_t>();
+}
+
+TEST_F(RegsTest, regs32_return_address_sp_offset) {
+  RegsTestTmpl<uint32_t> regs(20, 10, Regs::Location(Regs::LOCATION_SP_OFFSET, -2));
+
+  regs.set_sp(0x2002);
+  memory_->SetData32(0x2000, 0x12345678);
+  uint64_t value;
+  ASSERT_TRUE(regs.GetReturnAddressFromDefault(memory_, &value));
+  ASSERT_EQ(0x12345678U, value);
+}
+
+TEST_F(RegsTest, regs64_return_address_sp_offset) {
+  RegsTestTmpl<uint64_t> regs(20, 10, Regs::Location(Regs::LOCATION_SP_OFFSET, -8));
+
+  regs.set_sp(0x2008);
+  memory_->SetData64(0x2000, 0x12345678aabbccddULL);
+  uint64_t value;
+  ASSERT_TRUE(regs.GetReturnAddressFromDefault(memory_, &value));
+  ASSERT_EQ(0x12345678aabbccddULL, value);
+}
+
+TEST_F(RegsTest, rel_pc) {
+  RegsArm64 arm64;
+  ASSERT_EQ(0xcU, arm64.GetAdjustedPc(0x10, elf_.get()));
+  ASSERT_EQ(0x0U, arm64.GetAdjustedPc(0x4, elf_.get()));
+  ASSERT_EQ(0x3U, arm64.GetAdjustedPc(0x3, elf_.get()));
+  ASSERT_EQ(0x2U, arm64.GetAdjustedPc(0x2, elf_.get()));
+  ASSERT_EQ(0x1U, arm64.GetAdjustedPc(0x1, elf_.get()));
+  ASSERT_EQ(0x0U, arm64.GetAdjustedPc(0x0, elf_.get()));
+
+  RegsX86 x86;
+  ASSERT_EQ(0xffU,  x86.GetAdjustedPc(0x100, elf_.get()));
+  ASSERT_EQ(0x1U,  x86.GetAdjustedPc(0x2, elf_.get()));
+  ASSERT_EQ(0x0U,  x86.GetAdjustedPc(0x1, elf_.get()));
+  ASSERT_EQ(0x0U,  x86.GetAdjustedPc(0x0, elf_.get()));
+
+  RegsX86_64 x86_64;
+  ASSERT_EQ(0xffU,  x86_64.GetAdjustedPc(0x100, elf_.get()));
+  ASSERT_EQ(0x1U,  x86_64.GetAdjustedPc(0x2, elf_.get()));
+  ASSERT_EQ(0x0U,  x86_64.GetAdjustedPc(0x1, elf_.get()));
+  ASSERT_EQ(0x0U,  x86_64.GetAdjustedPc(0x0, elf_.get()));
+}
+
+TEST_F(RegsTest, rel_pc_arm) {
+  RegsArm arm;
+
+  // Check fence posts.
+  elf_interface_->set_load_bias(0);
+  ASSERT_EQ(3U,  arm.GetAdjustedPc(0x5, elf_.get()));
+  ASSERT_EQ(4U,  arm.GetAdjustedPc(0x4, elf_.get()));
+  ASSERT_EQ(3U,  arm.GetAdjustedPc(0x3, elf_.get()));
+  ASSERT_EQ(2U,  arm.GetAdjustedPc(0x2, elf_.get()));
+  ASSERT_EQ(1U,  arm.GetAdjustedPc(0x1, elf_.get()));
+  ASSERT_EQ(0U,  arm.GetAdjustedPc(0x0, elf_.get()));
+
+  elf_interface_->set_load_bias(0x100);
+  ASSERT_EQ(0xffU,  arm.GetAdjustedPc(0xff, elf_.get()));
+  ASSERT_EQ(0x103U,  arm.GetAdjustedPc(0x105, elf_.get()));
+  ASSERT_EQ(0x104U,  arm.GetAdjustedPc(0x104, elf_.get()));
+  ASSERT_EQ(0x103U,  arm.GetAdjustedPc(0x103, elf_.get()));
+  ASSERT_EQ(0x102U,  arm.GetAdjustedPc(0x102, elf_.get()));
+  ASSERT_EQ(0x101U,  arm.GetAdjustedPc(0x101, elf_.get()));
+  ASSERT_EQ(0x100U,  arm.GetAdjustedPc(0x100, elf_.get()));
+
+  // Check thumb instructions handling.
+  elf_interface_->set_load_bias(0);
+  memory_->SetData32(0x2000, 0);
+  ASSERT_EQ(0x2003U,  arm.GetAdjustedPc(0x2005, elf_.get()));
+  memory_->SetData32(0x2000, 0xe000f000);
+  ASSERT_EQ(0x2001U,  arm.GetAdjustedPc(0x2005, elf_.get()));
+
+  elf_interface_->set_load_bias(0x400);
+  memory_->SetData32(0x2100, 0);
+  ASSERT_EQ(0x2503U,  arm.GetAdjustedPc(0x2505, elf_.get()));
+  memory_->SetData32(0x2100, 0xf111f111);
+  ASSERT_EQ(0x2501U,  arm.GetAdjustedPc(0x2505, elf_.get()));
+}
+
+TEST_F(RegsTest, elf_invalid) {
+  Elf invalid_elf(new MemoryFake);
+  RegsArm regs_arm;
+  RegsArm64 regs_arm64;
+  RegsX86 regs_x86;
+  RegsX86_64 regs_x86_64;
+  MapInfo map_info{.start = 0x1000, .end = 0x2000};
+
+  regs_arm.set_pc(0x1500);
+  ASSERT_EQ(0x500U, regs_arm.GetRelPc(&invalid_elf, &map_info));
+  ASSERT_EQ(0x500U, regs_arm.GetAdjustedPc(0x500U, &invalid_elf));
+
+  regs_arm64.set_pc(0x1600);
+  ASSERT_EQ(0x600U, regs_arm64.GetRelPc(&invalid_elf, &map_info));
+  ASSERT_EQ(0x600U, regs_arm64.GetAdjustedPc(0x600U, &invalid_elf));
+
+  regs_x86.set_pc(0x1700);
+  ASSERT_EQ(0x700U, regs_x86.GetRelPc(&invalid_elf, &map_info));
+  ASSERT_EQ(0x700U, regs_x86.GetAdjustedPc(0x700U, &invalid_elf));
+
+  regs_x86_64.set_pc(0x1800);
+  ASSERT_EQ(0x800U, regs_x86_64.GetRelPc(&invalid_elf, &map_info));
+  ASSERT_EQ(0x800U, regs_x86_64.GetAdjustedPc(0x800U, &invalid_elf));
 }
diff --git a/libunwindstack/unwind_info.cpp b/libunwindstack/unwind_info.cpp
new file mode 100644
index 0000000..6f158b0
--- /dev/null
+++ b/libunwindstack/unwind_info.cpp
@@ -0,0 +1,121 @@
+/*
+ * Copyright (C) 2016 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 <elf.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <inttypes.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/mman.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+#include "ArmExidx.h"
+#include "Elf.h"
+#include "ElfInterface.h"
+#include "ElfInterfaceArm.h"
+#include "Log.h"
+
+void DumpArm(ElfInterfaceArm* interface) {
+  if (interface == nullptr) {
+    printf("No ARM Unwind Information.\n\n");
+    return;
+  }
+
+  printf("ARM Unwind Information:\n");
+  for (const auto& entry : interface->pt_loads()) {
+    uint64_t load_bias = entry.second.table_offset;
+    printf(" PC Range 0x%" PRIx64 " - 0x%" PRIx64 "\n", entry.second.offset + load_bias,
+           entry.second.table_size + load_bias);
+    for (auto addr : *interface) {
+      std::string name;
+      printf("  PC 0x%" PRIx64, addr + load_bias);
+      uint64_t func_offset;
+      if (interface->GetFunctionName(addr + load_bias + 1, &name, &func_offset) && !name.empty()) {
+        printf(" <%s>", name.c_str());
+      }
+      printf("\n");
+      uint64_t entry;
+      if (!interface->FindEntry(addr + load_bias, &entry)) {
+        printf("    Cannot find entry for address.\n");
+        continue;
+      }
+      ArmExidx arm(nullptr, interface->memory(), nullptr);
+      arm.set_log(true);
+      arm.set_log_skip_execution(true);
+      arm.set_log_indent(2);
+      if (!arm.ExtractEntryData(entry)) {
+        if (arm.status() != ARM_STATUS_NO_UNWIND) {
+          printf("    Error trying to extract data.\n");
+        }
+        continue;
+      }
+      if (arm.data()->size() > 0) {
+        if (!arm.Eval() && arm.status() != ARM_STATUS_NO_UNWIND) {
+          printf("      Error trying to evaluate dwarf data.\n");
+        }
+      }
+    }
+  }
+  printf("\n");
+}
+
+int main(int argc, char** argv) {
+  if (argc != 2) {
+    printf("Need to pass the name of an elf file to the program.\n");
+    return 1;
+  }
+
+  struct stat st;
+  if (stat(argv[1], &st) == -1) {
+    printf("Cannot stat %s: %s\n", argv[1], strerror(errno));
+    return 1;
+  }
+  if (!S_ISREG(st.st_mode)) {
+    printf("%s is not a regular file.\n", argv[1]);
+    return 1;
+  }
+  if (S_ISDIR(st.st_mode)) {
+    printf("%s is a directory.\n", argv[1]);
+    return 1;
+  }
+
+  // Send all log messages to stdout.
+  log_to_stdout(true);
+
+  MemoryFileAtOffset* memory = new MemoryFileAtOffset;
+  if (!memory->Init(argv[1], 0)) {
+    // Initializatation failed.
+    printf("Failed to init\n");
+    return 1;
+  }
+
+  Elf elf(memory);
+  if (!elf.Init() || !elf.valid()) {
+    printf("%s is not a valid elf file.\n", argv[1]);
+    return 1;
+  }
+
+  ElfInterface* interface = elf.interface();
+  if (elf.machine_type() == EM_ARM) {
+    DumpArm(reinterpret_cast<ElfInterfaceArm*>(interface));
+    printf("\n");
+  }
+
+  return 0;
+}
diff --git a/libutils/Android.bp b/libutils/Android.bp
index 68ce63d..b772b78 100644
--- a/libutils/Android.bp
+++ b/libutils/Android.bp
@@ -17,9 +17,12 @@
     host_supported: true,
     export_include_dirs: ["include"],
     target: {
+        linux_bionic: {
+            enabled: true,
+        },
         windows: {
-           enabled: true,
-      },
+            enabled: true,
+        },
     },
 }
 
diff --git a/libutils/include/utils/TypeHelpers.h b/libutils/include/utils/TypeHelpers.h
index 2a25227..28fbca5 100644
--- a/libutils/include/utils/TypeHelpers.h
+++ b/libutils/include/utils/TypeHelpers.h
@@ -36,7 +36,7 @@
 template <typename T> struct trait_trivial_dtor { enum { value = false }; };
 template <typename T> struct trait_trivial_copy { enum { value = false }; };
 template <typename T> struct trait_trivial_move { enum { value = false }; };
-template <typename T> struct trait_pointer      { enum { value = false }; };    
+template <typename T> struct trait_pointer      { enum { value = false }; };
 template <typename T> struct trait_pointer<T*>  { enum { value = true }; };
 
 template <typename TYPE>
@@ -59,13 +59,13 @@
 struct aggregate_traits {
     enum {
         is_pointer          = false,
-        has_trivial_ctor    = 
+        has_trivial_ctor    =
             traits<T>::has_trivial_ctor && traits<U>::has_trivial_ctor,
-        has_trivial_dtor    = 
+        has_trivial_dtor    =
             traits<T>::has_trivial_dtor && traits<U>::has_trivial_dtor,
-        has_trivial_copy    = 
+        has_trivial_copy    =
             traits<T>::has_trivial_copy && traits<U>::has_trivial_copy,
-        has_trivial_move    = 
+        has_trivial_move    =
             traits<T>::has_trivial_move && traits<U>::has_trivial_move
     };
 };
diff --git a/libutils/include/utils/Vector.h b/libutils/include/utils/Vector.h
index 9a643f9..3189fd6 100644
--- a/libutils/include/utils/Vector.h
+++ b/libutils/include/utils/Vector.h
@@ -42,11 +42,11 @@
 {
 public:
             typedef TYPE    value_type;
-    
-    /*! 
+
+    /*!
      * Constructors and destructors
      */
-    
+
                             Vector();
                             Vector(const Vector<TYPE>& rhs);
     explicit                Vector(const SortedVector<TYPE>& rhs);
@@ -54,7 +54,7 @@
 
     /*! copy operator */
             const Vector<TYPE>&     operator = (const Vector<TYPE>& rhs) const;
-            Vector<TYPE>&           operator = (const Vector<TYPE>& rhs);    
+            Vector<TYPE>&           operator = (const Vector<TYPE>& rhs);
 
             const Vector<TYPE>&     operator = (const SortedVector<TYPE>& rhs) const;
             Vector<TYPE>&           operator = (const SortedVector<TYPE>& rhs);
@@ -65,7 +65,7 @@
 
     inline  void            clear()             { VectorImpl::clear(); }
 
-    /*! 
+    /*!
      * vector stats
      */
 
@@ -87,13 +87,13 @@
     /*!
      * C-style array access
      */
-     
-    //! read-only C-style access 
+
+    //! read-only C-style access
     inline  const TYPE*     array() const;
     //! read-write C-style access
             TYPE*           editArray();
-    
-    /*! 
+
+    /*!
      * accessors
      */
 
@@ -113,10 +113,10 @@
     //! grants right access to the top of the stack (last element)
             TYPE&           editTop();
 
-            /*! 
+            /*!
              * append/insert another vector
              */
-            
+
     //! insert another vector at a given index
             ssize_t         insertVectorAt(const Vector<TYPE>& vector, size_t index);
 
@@ -130,10 +130,10 @@
     //! append an array at the end of this vector
             ssize_t         appendArray(const TYPE* array, size_t length);
 
-            /*! 
+            /*!
              * add/insert/replace items
              */
-             
+
     //! insert one or several items initialized with their default constructor
     inline  ssize_t         insertAt(size_t index, size_t numItems = 1);
     //! insert one or several items initialized from a prototype item
@@ -147,7 +147,7 @@
     //! same as push() but returns the index the item was added at (or an error)
     inline  ssize_t         add();
     //! same as push() but returns the index the item was added at (or an error)
-            ssize_t         add(const TYPE& item);            
+            ssize_t         add(const TYPE& item);
     //! replace an item with a new one initialized with its default constructor
     inline  ssize_t         replaceAt(size_t index);
     //! replace an item with a new one
@@ -165,10 +165,10 @@
     /*!
      * sort (stable) the array
      */
-     
+
      typedef int (*compar_t)(const TYPE* lhs, const TYPE* rhs);
      typedef int (*compar_r_t)(const TYPE* lhs, const TYPE* rhs, void* state);
-     
+
      inline status_t        sort(compar_t cmp);
      inline status_t        sort(compar_r_t cmp, void* state);
 
@@ -237,7 +237,7 @@
 template<class TYPE> inline
 Vector<TYPE>& Vector<TYPE>::operator = (const Vector<TYPE>& rhs) {
     VectorImpl::operator = (rhs);
-    return *this; 
+    return *this;
 }
 
 template<class TYPE> inline
@@ -255,7 +255,7 @@
 template<class TYPE> inline
 const Vector<TYPE>& Vector<TYPE>::operator = (const SortedVector<TYPE>& rhs) const {
     VectorImpl::operator = (rhs);
-    return *this; 
+    return *this;
 }
 
 template<class TYPE> inline
diff --git a/logcat/logcat.cpp b/logcat/logcat.cpp
index 4da5030..8134936 100644
--- a/logcat/logcat.cpp
+++ b/logcat/logcat.cpp
@@ -41,6 +41,7 @@
 #include <vector>
 
 #include <android-base/file.h>
+#include <android-base/properties.h>
 #include <android-base/stringprintf.h>
 #include <android-base/strings.h>
 #include <cutils/sched_policy.h>
@@ -1195,39 +1196,71 @@
             } break;
 
             case 'Q':
-#define KERNEL_OPTION "androidboot.logcat="
+#define LOGCAT_FILTER "androidboot.logcat="
+#define CONSOLE_PIPE_OPTION "androidboot.consolepipe="
 #define CONSOLE_OPTION "androidboot.console="
+#define QEMU_PROPERTY "ro.kernel.qemu"
+#define QEMU_CMDLINE "qemu.cmdline"
                 // This is a *hidden* option used to start a version of logcat
                 // in an emulated device only.  It basically looks for
                 // androidboot.logcat= on the kernel command line.  If
                 // something is found, it extracts a log filter and uses it to
-                // run the program.  If nothing is found, the program should
-                // quit immediately.
+                // run the program. The logcat output will go to consolepipe if
+                // androiboot.consolepipe (e.g. qemu_pipe) is given, otherwise,
+                // it goes to androidboot.console (e.g. tty)
                 {
-                    std::string cmdline;
-                    android::base::ReadFileToString("/proc/cmdline", &cmdline);
-
-                    const char* logcat = strstr(cmdline.c_str(), KERNEL_OPTION);
-                    // if nothing found or invalid filters, exit quietly
-                    if (!logcat) {
+                    // if not in emulator, exit quietly
+                    if (false == android::base::GetBoolProperty(QEMU_PROPERTY, false)) {
                         context->retval = EXIT_SUCCESS;
                         goto exit;
                     }
 
-                    const char* p = logcat + strlen(KERNEL_OPTION);
+                    std::string cmdline = android::base::GetProperty(QEMU_CMDLINE, "");
+                    if (cmdline.empty()) {
+                        android::base::ReadFileToString("/proc/cmdline", &cmdline);
+                    }
+
+                    const char* logcatFilter = strstr(cmdline.c_str(), LOGCAT_FILTER);
+                    // if nothing found or invalid filters, exit quietly
+                    if (!logcatFilter) {
+                        context->retval = EXIT_SUCCESS;
+                        goto exit;
+                    }
+
+                    const char* p = logcatFilter + strlen(LOGCAT_FILTER);
                     const char* q = strpbrk(p, " \t\n\r");
                     if (!q) q = p + strlen(p);
                     forceFilters = std::string(p, q);
 
-                    // redirect our output to the emulator console
+                    // redirect our output to the emulator console pipe or console
+                    const char* consolePipe =
+                        strstr(cmdline.c_str(), CONSOLE_PIPE_OPTION);
                     const char* console =
                         strstr(cmdline.c_str(), CONSOLE_OPTION);
-                    if (!console) break;
 
-                    p = console + strlen(CONSOLE_OPTION);
+                    if (consolePipe) {
+                        p = consolePipe + strlen(CONSOLE_PIPE_OPTION);
+                    } else if (console) {
+                        p = console + strlen(CONSOLE_OPTION);
+                    } else {
+                        context->retval = EXIT_FAILURE;
+                        goto exit;
+                    }
+
                     q = strpbrk(p, " \t\n\r");
                     int len = q ? q - p : strlen(p);
                     std::string devname = "/dev/" + std::string(p, len);
+                    std::string pipePurpose("pipe:logcat");
+                    if (consolePipe) {
+                        // example: "qemu_pipe,pipe:logcat"
+                        // upon opening of /dev/qemu_pipe, the "pipe:logcat"
+                        // string with trailing '\0' should be written to the fd
+                        size_t pos = devname.find(",");
+                        if (pos != std::string::npos) {
+                            pipePurpose = devname.substr(pos + 1);
+                            devname = devname.substr(0, pos);
+                        }
+                    }
                     cmdline.erase();
 
                     if (context->error) {
@@ -1239,6 +1272,16 @@
                     devname.erase();
                     if (!fp) break;
 
+                    if (consolePipe) {
+                        // need the trailing '\0'
+                        if(!android::base::WriteFully(fileno(fp), pipePurpose.c_str(),
+                                    pipePurpose.size() + 1)) {
+                            fclose(fp);
+                            context->retval = EXIT_FAILURE;
+                            goto exit;
+                        }
+                    }
+
                     // close output and error channels, replace with console
                     android::close_output(context);
                     android::close_error(context);
diff --git a/logd/FlushCommand.cpp b/logd/FlushCommand.cpp
index 5a5c0d9..c67d2bf 100644
--- a/logd/FlushCommand.cpp
+++ b/logd/FlushCommand.cpp
@@ -27,7 +27,7 @@
 #include "LogUtils.h"
 
 FlushCommand::FlushCommand(LogReader& reader, bool nonBlock, unsigned long tail,
-                           unsigned int logMask, pid_t pid, uint64_t start,
+                           unsigned int logMask, pid_t pid, log_time start,
                            uint64_t timeout)
     : mReader(reader),
       mNonBlock(nonBlock),
@@ -35,7 +35,7 @@
       mLogMask(logMask),
       mPid(pid),
       mStart(start),
-      mTimeout((start > 1) ? timeout : 0) {
+      mTimeout((start != log_time::EPOCH) ? timeout : 0) {
 }
 
 // runSocketCommand is called once for every open client on the
@@ -57,8 +57,18 @@
         entry = (*it);
         if (entry->mClient == client) {
             if (entry->mTimeout.tv_sec || entry->mTimeout.tv_nsec) {
-                LogTimeEntry::unlock();
-                return;
+                if (mReader.logbuf().isMonotonic()) {
+                    LogTimeEntry::unlock();
+                    return;
+                }
+                // If the user changes the time in a gross manner that
+                // invalidates the timeout, fall through and trigger.
+                log_time now(CLOCK_REALTIME);
+                if (((entry->mEnd + entry->mTimeout) > now) &&
+                    (now > entry->mEnd)) {
+                    LogTimeEntry::unlock();
+                    return;
+                }
             }
             entry->triggerReader_Locked();
             if (entry->runningReader_Locked()) {
diff --git a/logd/FlushCommand.h b/logd/FlushCommand.h
index 45cb9c5..7cdd03f 100644
--- a/logd/FlushCommand.h
+++ b/logd/FlushCommand.h
@@ -16,7 +16,7 @@
 #ifndef _FLUSH_COMMAND_H
 #define _FLUSH_COMMAND_H
 
-#include <android/log.h>
+#include <private/android_logger.h>
 #include <sysutils/SocketClientCommand.h>
 
 class LogBufferElement;
@@ -31,13 +31,13 @@
     unsigned long mTail;
     unsigned int mLogMask;
     pid_t mPid;
-    uint64_t mStart;
+    log_time mStart;
     uint64_t mTimeout;
 
    public:
     explicit FlushCommand(LogReader& mReader, bool nonBlock = false,
                           unsigned long tail = -1, unsigned int logMask = -1,
-                          pid_t pid = 0, uint64_t start = 1,
+                          pid_t pid = 0, log_time start = log_time::EPOCH,
                           uint64_t timeout = 0);
     virtual void runSocketCommand(SocketClient* client);
 
diff --git a/logd/LogBuffer.cpp b/logd/LogBuffer.cpp
index 60d647d..dd78275 100644
--- a/logd/LogBuffer.cpp
+++ b/logd/LogBuffer.cpp
@@ -183,7 +183,7 @@
     lenr -= avcr - msgr;
     if (lenl != lenr) return DIFFERENT;
     // TODO: After b/35468874 is addressed, revisit "lenl > strlen(avc)"
-    // condition, it might become superflous.
+    // condition, it might become superfluous.
     if (lenl > strlen(avc) &&
         fastcmp<memcmp>(avcl + strlen(avc), avcr + strlen(avc),
                         lenl - strlen(avc))) {
@@ -372,22 +372,22 @@
 
 // assumes mLogElementsLock held, owns elem, will look after garbage collection
 void LogBuffer::log(LogBufferElement* elem) {
+    // cap on how far back we will sort in-place, otherwise append
+    static uint32_t too_far_back = 5;  // five seconds
     // Insert elements in time sorted order if possible
     //  NB: if end is region locked, place element at end of list
     LogBufferElementCollection::iterator it = mLogElements.end();
     LogBufferElementCollection::iterator last = it;
-    while (last != mLogElements.begin()) {
-        --it;
-        if ((*it)->getRealTime() <= elem->getRealTime()) {
-            break;
-        }
-        last = it;
-    }
-
-    if (last == mLogElements.end()) {
+    if (__predict_true(it != mLogElements.begin())) --it;
+    if (__predict_false(it == mLogElements.begin()) ||
+        __predict_true((*it)->getRealTime() <= elem->getRealTime()) ||
+        __predict_false((((*it)->getRealTime().tv_sec - too_far_back) >
+                         elem->getRealTime().tv_sec) &&
+                        (elem->getLogId() != LOG_ID_KERNEL) &&
+                        ((*it)->getLogId() != LOG_ID_KERNEL))) {
         mLogElements.push_back(elem);
     } else {
-        uint64_t end = 1;
+        log_time end = log_time::EPOCH;
         bool end_set = false;
         bool end_always = false;
 
@@ -401,6 +401,7 @@
                     end_always = true;
                     break;
                 }
+                // it passing mEnd is blocked by the following checks.
                 if (!end_set || (end <= entry->mEnd)) {
                     end = entry->mEnd;
                     end_set = true;
@@ -409,12 +410,20 @@
             times++;
         }
 
-        if (end_always || (end_set && (end >= (*last)->getSequence()))) {
+        if (end_always || (end_set && (end > (*it)->getRealTime()))) {
             mLogElements.push_back(elem);
         } else {
+            // should be short as timestamps are localized near end()
+            do {
+                last = it;
+                if (__predict_false(it == mLogElements.begin())) {
+                    break;
+                }
+                --it;
+            } while (((*it)->getRealTime() > elem->getRealTime()) &&
+                     (!end_set || (end <= (*it)->getRealTime())));
             mLogElements.insert(last, elem);
         }
-
         LogTimeEntry::unlock();
     }
 
@@ -589,12 +598,12 @@
     }
 
     void clear(LogBufferElement* element) {
-        uint64_t current =
-            element->getRealTime().nsec() - (EXPIRE_RATELIMIT * NS_PER_SEC);
+        log_time current =
+            element->getRealTime() - log_time(EXPIRE_RATELIMIT, 0);
         for (LogBufferElementMap::iterator it = map.begin(); it != map.end();) {
             LogBufferElement* mapElement = it->second;
             if ((mapElement->getDropped() >= EXPIRE_THRESHOLD) &&
-                (current > mapElement->getRealTime().nsec())) {
+                (current > mapElement->getRealTime())) {
                 it = map.erase(it);
             } else {
                 ++it;
@@ -690,7 +699,7 @@
                 mLastSet[id] = true;
             }
 
-            if (oldest && (oldest->mStart <= element->getSequence())) {
+            if (oldest && (oldest->mStart <= element->getRealTime().nsec())) {
                 busy = true;
                 if (oldest->mTimeout.tv_sec || oldest->mTimeout.tv_nsec) {
                     oldest->triggerReader_Locked();
@@ -782,7 +791,7 @@
         while (it != mLogElements.end()) {
             LogBufferElement* element = *it;
 
-            if (oldest && (oldest->mStart <= element->getSequence())) {
+            if (oldest && (oldest->mStart <= element->getRealTime().nsec())) {
                 busy = true;
                 if (oldest->mTimeout.tv_sec || oldest->mTimeout.tv_nsec) {
                     oldest->triggerReader_Locked();
@@ -936,7 +945,7 @@
             mLastSet[id] = true;
         }
 
-        if (oldest && (oldest->mStart <= element->getSequence())) {
+        if (oldest && (oldest->mStart <= element->getRealTime().nsec())) {
             busy = true;
             if (whitelist) {
                 break;
@@ -980,7 +989,7 @@
                 mLastSet[id] = true;
             }
 
-            if (oldest && (oldest->mStart <= element->getSequence())) {
+            if (oldest && (oldest->mStart <= element->getRealTime().nsec())) {
                 busy = true;
                 if (stats.sizes(id) > (2 * log_buffer_size(id))) {
                     // kick a misbehaving log reader client off the island
@@ -1073,32 +1082,37 @@
     return retval;
 }
 
-uint64_t LogBuffer::flushTo(
-    SocketClient* reader, const uint64_t start, bool privileged, bool security,
+log_time LogBuffer::flushTo(
+    SocketClient* reader, const log_time& start, bool privileged, bool security,
     int (*filter)(const LogBufferElement* element, void* arg), void* arg) {
     LogBufferElementCollection::iterator it;
-    uint64_t max = start;
     uid_t uid = reader->getUid();
 
     pthread_mutex_lock(&mLogElementsLock);
 
-    if (start <= 1) {
+    if (start == log_time::EPOCH) {
         // client wants to start from the beginning
         it = mLogElements.begin();
     } else {
+        LogBufferElementCollection::iterator last = mLogElements.begin();
+        // 30 second limit to continue search for out-of-order entries.
+        log_time min = start - log_time(30, 0);
         // Client wants to start from some specified time. Chances are
         // we are better off starting from the end of the time sorted list.
         for (it = mLogElements.end(); it != mLogElements.begin();
              /* do nothing */) {
             --it;
             LogBufferElement* element = *it;
-            if (element->getSequence() <= start) {
-                it++;
+            if (element->getRealTime() > start) {
+                last = it;
+            } else if (element->getRealTime() < min) {
                 break;
             }
         }
+        it = last;
     }
 
+    log_time max = start;
     // Help detect if the valid message before is from the same source so
     // we can differentiate chatty filter types.
     pid_t lastTid[LOG_ID_MAX] = { 0 };
@@ -1114,7 +1128,7 @@
             continue;
         }
 
-        if (element->getSequence() <= start) {
+        if (element->getRealTime() <= start) {
             continue;
         }
 
diff --git a/logd/LogBuffer.h b/logd/LogBuffer.h
index 92b0297..fcf6b9a 100644
--- a/logd/LogBuffer.h
+++ b/logd/LogBuffer.h
@@ -115,7 +115,7 @@
 
     int log(log_id_t log_id, log_time realtime, uid_t uid, pid_t pid, pid_t tid,
             const char* msg, unsigned short len);
-    uint64_t flushTo(SocketClient* writer, const uint64_t start,
+    log_time flushTo(SocketClient* writer, const log_time& start,
                      bool privileged, bool security,
                      int (*filter)(const LogBufferElement* element,
                                    void* arg) = NULL,
diff --git a/logd/LogBufferElement.cpp b/logd/LogBufferElement.cpp
index 5ba3a15..81356fe 100644
--- a/logd/LogBufferElement.cpp
+++ b/logd/LogBufferElement.cpp
@@ -30,7 +30,7 @@
 #include "LogReader.h"
 #include "LogUtils.h"
 
-const uint64_t LogBufferElement::FLUSH_ERROR(0);
+const log_time LogBufferElement::FLUSH_ERROR((uint32_t)-1, (uint32_t)-1);
 atomic_int_fast64_t LogBufferElement::sequence(1);
 
 LogBufferElement::LogBufferElement(log_id_t log_id, log_time realtime,
@@ -39,7 +39,6 @@
     : mUid(uid),
       mPid(pid),
       mTid(tid),
-      mSequence(sequence.fetch_add(1, memory_order_relaxed)),
       mRealTime(realtime),
       mMsgLen(len),
       mLogId(log_id) {
@@ -55,7 +54,6 @@
       mUid(elem.mUid),
       mPid(elem.mPid),
       mTid(elem.mTid),
-      mSequence(elem.mSequence),
       mRealTime(elem.mRealTime),
       mMsgLen(elem.mMsgLen),
       mLogId(elem.mLogId) {
@@ -206,7 +204,7 @@
     return retval;
 }
 
-uint64_t LogBufferElement::flushTo(SocketClient* reader, LogBuffer* parent,
+log_time LogBufferElement::flushTo(SocketClient* reader, LogBuffer* parent,
                                    bool privileged, bool lastSame) {
     struct logger_entry_v4 entry;
 
@@ -229,7 +227,7 @@
 
     if (!mMsg) {
         entry.len = populateDroppedMessage(buffer, parent, lastSame);
-        if (!entry.len) return mSequence;
+        if (!entry.len) return mRealTime;
         iovec[1].iov_base = buffer;
     } else {
         entry.len = mMsgLen;
@@ -237,7 +235,7 @@
     }
     iovec[1].iov_len = entry.len;
 
-    uint64_t retval = reader->sendDatav(iovec, 2) ? FLUSH_ERROR : mSequence;
+    log_time retval = reader->sendDatav(iovec, 2) ? FLUSH_ERROR : mRealTime;
 
     if (buffer) free(buffer);
 
diff --git a/logd/LogBufferElement.h b/logd/LogBufferElement.h
index 43990e8..814ec87 100644
--- a/logd/LogBufferElement.h
+++ b/logd/LogBufferElement.h
@@ -40,7 +40,6 @@
     const uint32_t mUid;
     const uint32_t mPid;
     const uint32_t mTid;
-    const uint64_t mSequence;
     log_time mRealTime;
     char* mMsg;
     union {
@@ -96,18 +95,12 @@
     const char* getMsg() const {
         return mMsg;
     }
-    uint64_t getSequence(void) const {
-        return mSequence;
-    }
-    static uint64_t getCurrentSequence(void) {
-        return sequence.load(memory_order_relaxed);
-    }
     log_time getRealTime(void) const {
         return mRealTime;
     }
 
-    static const uint64_t FLUSH_ERROR;
-    uint64_t flushTo(SocketClient* writer, LogBuffer* parent, bool privileged,
+    static const log_time FLUSH_ERROR;
+    log_time flushTo(SocketClient* writer, LogBuffer* parent, bool privileged,
                      bool lastSame);
 };
 
diff --git a/logd/LogReader.cpp b/logd/LogReader.cpp
index 76f5798..620d4d0 100644
--- a/logd/LogReader.cpp
+++ b/logd/LogReader.cpp
@@ -116,57 +116,70 @@
         nonBlock = true;
     }
 
-    uint64_t sequence = 1;
-    // Convert realtime to sequence number
-    if (start != log_time::EPOCH) {
-        class LogFindStart {
+    log_time sequence = start;
+    //
+    // This somewhat expensive data validation operation is required
+    // for non-blocking, with timeout.  The incoming timestamp must be
+    // in range of the list, if not, return immediately.  This is
+    // used to prevent us from from getting stuck in timeout processing
+    // with an invalid time.
+    //
+    // Find if time is really present in the logs, monotonic or real, implicit
+    // conversion from monotonic or real as necessary to perform the check.
+    // Exit in the check loop ASAP as you find a transition from older to
+    // newer, but use the last entry found to ensure overlap.
+    //
+    if (nonBlock && (sequence != log_time::EPOCH) && timeout) {
+        class LogFindStart {  // A lambda by another name
+           private:
             const pid_t mPid;
             const unsigned mLogMask;
-            bool startTimeSet;
-            log_time& start;
-            uint64_t& sequence;
-            uint64_t last;
-            bool isMonotonic;
+            bool mStartTimeSet;
+            log_time mStart;
+            log_time& mSequence;
+            log_time mLast;
+            bool mIsMonotonic;
 
            public:
-            LogFindStart(unsigned logMask, pid_t pid, log_time& start,
-                         uint64_t& sequence, bool isMonotonic)
+            LogFindStart(pid_t pid, unsigned logMask, log_time& sequence,
+                         bool isMonotonic)
                 : mPid(pid),
                   mLogMask(logMask),
-                  startTimeSet(false),
-                  start(start),
-                  sequence(sequence),
-                  last(sequence),
-                  isMonotonic(isMonotonic) {
+                  mStartTimeSet(false),
+                  mStart(sequence),
+                  mSequence(sequence),
+                  mLast(sequence),
+                  mIsMonotonic(isMonotonic) {
             }
 
             static int callback(const LogBufferElement* element, void* obj) {
                 LogFindStart* me = reinterpret_cast<LogFindStart*>(obj);
                 if ((!me->mPid || (me->mPid == element->getPid())) &&
                     (me->mLogMask & (1 << element->getLogId()))) {
-                    if (me->start == element->getRealTime()) {
-                        me->sequence = element->getSequence();
-                        me->startTimeSet = true;
+                    log_time real = element->getRealTime();
+                    if (me->mStart == real) {
+                        me->mSequence = real;
+                        me->mStartTimeSet = true;
                         return -1;
-                    } else if (!me->isMonotonic ||
-                               android::isMonotonic(element->getRealTime())) {
-                        if (me->start < element->getRealTime()) {
-                            me->sequence = me->last;
-                            me->startTimeSet = true;
+                    } else if (!me->mIsMonotonic || android::isMonotonic(real)) {
+                        if (me->mStart < real) {
+                            me->mSequence = me->mLast;
+                            me->mStartTimeSet = true;
                             return -1;
                         }
-                        me->last = element->getSequence();
+                        me->mLast = real;
                     } else {
-                        me->last = element->getSequence();
+                        me->mLast = real;
                     }
                 }
                 return false;
             }
 
             bool found() {
-                return startTimeSet;
+                return mStartTimeSet;
             }
-        } logFindStart(logMask, pid, start, sequence,
+
+        } logFindStart(pid, logMask, sequence,
                        logbuf().isMonotonic() && android::isMonotonic(start));
 
         logbuf().flushTo(cli, sequence, FlushCommand::hasReadLogs(cli),
@@ -174,11 +187,8 @@
                          logFindStart.callback, &logFindStart);
 
         if (!logFindStart.found()) {
-            if (nonBlock) {
-                doSocketDelete(cli);
-                return false;
-            }
-            sequence = LogBufferElement::getCurrentSequence();
+            doSocketDelete(cli);
+            return false;
         }
     }
 
diff --git a/logd/LogTimes.cpp b/logd/LogTimes.cpp
index bdaeb75..04e531f 100644
--- a/logd/LogTimes.cpp
+++ b/logd/LogTimes.cpp
@@ -17,6 +17,8 @@
 #include <errno.h>
 #include <sys/prctl.h>
 
+#include <private/android_logger.h>
+
 #include "FlushCommand.h"
 #include "LogBuffer.h"
 #include "LogReader.h"
@@ -26,7 +28,7 @@
 
 LogTimeEntry::LogTimeEntry(LogReader& reader, SocketClient* client,
                            bool nonBlock, unsigned long tail,
-                           unsigned int logMask, pid_t pid, uint64_t start,
+                           unsigned int logMask, pid_t pid, log_time start,
                            uint64_t timeout)
     : mRefCount(1),
       mRelease(false),
@@ -42,7 +44,7 @@
       mClient(client),
       mStart(start),
       mNonBlock(nonBlock),
-      mEnd(LogBufferElement::getCurrentSequence()) {
+      mEnd(log_time(android_log_clockid())) {
     mTimeout.tv_sec = timeout / NS_PER_SEC;
     mTimeout.tv_nsec = timeout % NS_PER_SEC;
     pthread_cond_init(&threadTriggeredCondition, NULL);
@@ -132,7 +134,7 @@
 
     lock();
 
-    uint64_t start = me->mStart;
+    log_time start = me->mStart;
 
     while (me->threadRunning && !me->isError_Locked()) {
         if (me->mTimeout.tv_sec || me->mTimeout.tv_nsec) {
@@ -163,7 +165,7 @@
             break;
         }
 
-        me->mStart = start + 1;
+        me->mStart = start + log_time(0, 1);
 
         if (me->mNonBlock || !me->threadRunning || me->isError_Locked()) {
             break;
@@ -198,7 +200,7 @@
     }
 
     if (me->mCount == 0) {
-        me->mStart = element->getSequence();
+        me->mStart = element->getRealTime();
     }
 
     if ((!me->mPid || (me->mPid == element->getPid())) &&
@@ -217,7 +219,7 @@
 
     LogTimeEntry::lock();
 
-    me->mStart = element->getSequence();
+    me->mStart = element->getRealTime();
 
     if (me->skipAhead[element->getLogId()]) {
         me->skipAhead[element->getLogId()]--;
diff --git a/logd/LogTimes.h b/logd/LogTimes.h
index 23fdf4e..9a3ddab 100644
--- a/logd/LogTimes.h
+++ b/logd/LogTimes.h
@@ -51,13 +51,13 @@
    public:
     LogTimeEntry(LogReader& reader, SocketClient* client, bool nonBlock,
                  unsigned long tail, unsigned int logMask, pid_t pid,
-                 uint64_t start, uint64_t timeout);
+                 log_time start, uint64_t timeout);
 
     SocketClient* mClient;
-    uint64_t mStart;
+    log_time mStart;
     struct timespec mTimeout;
     const bool mNonBlock;
-    const uint64_t mEnd;  // only relevant if mNonBlock
+    const log_time mEnd;  // only relevant if mNonBlock
 
     // Protect List manipulations
     static void lock(void) {
diff --git a/rootdir/init-debug.rc b/rootdir/init-debug.rc
index 44d34d8..435d4cb 100644
--- a/rootdir/init-debug.rc
+++ b/rootdir/init-debug.rc
@@ -6,6 +6,3 @@
 
 on property:persist.mmc.cache_size=*
     write /sys/block/mmcblk0/cache_size ${persist.mmc.cache_size}
-
-on early-init
-    mount debugfs debugfs /sys/kernel/debug