Index: include/llvm/Support/FileSystem.h
===================================================================
--- include/llvm/Support/FileSystem.h
+++ include/llvm/Support/FileSystem.h
@@ -140,11 +140,14 @@
   #if defined(LLVM_ON_UNIX)
   dev_t fs_st_dev;
   ino_t fs_st_ino;
+  time_t fs_st_atime;
   time_t fs_st_mtime;
   uid_t fs_st_uid;
   gid_t fs_st_gid;
   off_t fs_st_size;
   #elif defined (LLVM_ON_WIN32)
+  uint32_t LastAccessedTimeHigh;
+  uint32_t LastAccessedTimeLow;
   uint32_t LastWriteTimeHigh;
   uint32_t LastWriteTimeLow;
   uint32_t VolumeSerialNumber;
@@ -159,43 +162,50 @@
 
 public:
   #if defined(LLVM_ON_UNIX)
-    file_status() : fs_st_dev(0), fs_st_ino(0), fs_st_mtime(0),
+  file_status()
+      : fs_st_dev(0), fs_st_ino(0), fs_st_atime(0), fs_st_mtime(0),
         fs_st_uid(0), fs_st_gid(0), fs_st_size(0),
         Type(file_type::status_error), Perms(perms_not_known) {}
 
-    file_status(file_type Type) : fs_st_dev(0), fs_st_ino(0), fs_st_mtime(0),
+  file_status(file_type Type)
+      : fs_st_dev(0), fs_st_ino(0), fs_st_atime(0), fs_st_mtime(0),
         fs_st_uid(0), fs_st_gid(0), fs_st_size(0), Type(Type),
         Perms(perms_not_known) {}
 
-    file_status(file_type Type, perms Perms, dev_t Dev, ino_t Ino, time_t MTime,
-                uid_t UID, gid_t GID, off_t Size)
-        : fs_st_dev(Dev), fs_st_ino(Ino), fs_st_mtime(MTime), fs_st_uid(UID),
-          fs_st_gid(GID), fs_st_size(Size), Type(Type), Perms(Perms) {}
+  file_status(file_type Type, perms Perms, dev_t Dev, ino_t Ino, time_t MTime,
+              time_t ATime, uid_t UID, gid_t GID, off_t Size)
+      : fs_st_dev(Dev), fs_st_ino(Ino), fs_st_atime(ATime), fs_st_mtime(MTime),
+        fs_st_uid(UID), fs_st_gid(GID), fs_st_size(Size), Type(Type),
+        Perms(Perms) {}
   #elif defined(LLVM_ON_WIN32)
-    file_status() : LastWriteTimeHigh(0), LastWriteTimeLow(0),
-        VolumeSerialNumber(0), FileSizeHigh(0), FileSizeLow(0),
-        FileIndexHigh(0), FileIndexLow(0), Type(file_type::status_error),
-        Perms(perms_not_known) {}
+  file_status()
+      : LastAccessedTimeHigh(0), LastAccessedTimeLow(0), LastWriteTimeHigh(0),
+        LastWriteTimeLow(0), VolumeSerialNumber(0), FileSizeHigh(0),
+        FileSizeLow(0), FileIndexHigh(0), FileIndexLow(0),
+        Type(file_type::status_error), Perms(perms_not_known) {}
 
-    file_status(file_type Type) : LastWriteTimeHigh(0), LastWriteTimeLow(0),
-        VolumeSerialNumber(0), FileSizeHigh(0), FileSizeLow(0),
-        FileIndexHigh(0), FileIndexLow(0), Type(Type),
+  file_status(file_type Type)
+      : LastAccessedTimeHigh(0), LastAccessedTimeLow(0), LastWriteTimeHigh(0),
+        LastWriteTimeLow(0), VolumeSerialNumber(0), FileSizeHigh(0),
+        FileSizeLow(0), FileIndexHigh(0), FileIndexLow(0), Type(Type),
         Perms(perms_not_known) {}
 
-    file_status(file_type Type, uint32_t LastWriteTimeHigh,
-                uint32_t LastWriteTimeLow, uint32_t VolumeSerialNumber,
-                uint32_t FileSizeHigh, uint32_t FileSizeLow,
-                uint32_t FileIndexHigh, uint32_t FileIndexLow)
-        : LastWriteTimeHigh(LastWriteTimeHigh),
-          LastWriteTimeLow(LastWriteTimeLow),
-          VolumeSerialNumber(VolumeSerialNumber), FileSizeHigh(FileSizeHigh),
-          FileSizeLow(FileSizeLow), FileIndexHigh(FileIndexHigh),
-          FileIndexLow(FileIndexLow), Type(Type), Perms(perms_not_known) {}
+  file_status(file_type Type, uint32_t LastWriteTimeHigh,
+              uint32_t LastWriteTimeLow, uint32_t VolumeSerialNumber,
+              uint32_t FileSizeHigh, uint32_t FileSizeLow,
+              uint32_t FileIndexHigh, uint32_t FileIndexLow)
+      : LastAccessedTimeHigh(0), LastAccessedTimeLow(0),
+        LastWriteTimeHigh(LastWriteTimeHigh),
+        LastWriteTimeLow(LastWriteTimeLow),
+        VolumeSerialNumber(VolumeSerialNumber), FileSizeHigh(FileSizeHigh),
+        FileSizeLow(FileSizeLow), FileIndexHigh(FileIndexHigh),
+        FileIndexLow(FileIndexLow), Type(Type), Perms(perms_not_known) {}
   #endif
 
   // getters
   file_type type() const { return Type; }
   perms permissions() const { return Perms; }
+  TimeValue getLastAccessedTime() const;
   TimeValue getLastModificationTime() const;
   UniqueID getUniqueID() const;
 
Index: lib/Support/Unix/Path.inc
===================================================================
--- lib/Support/Unix/Path.inc
+++ lib/Support/Unix/Path.inc
@@ -174,6 +174,12 @@
   return "";
 }
 
+TimeValue file_status::getLastAccessedTime() const {
+  TimeValue Ret;
+  Ret.fromEpochTime(fs_st_atime);
+  return Ret;
+}
+
 TimeValue file_status::getLastModificationTime() const {
   TimeValue Ret;
   Ret.fromEpochTime(fs_st_mtime);
@@ -373,8 +379,9 @@
 
   perms Perms = static_cast<perms>(Status.st_mode);
   Result =
-      file_status(Type, Perms, Status.st_dev, Status.st_ino, Status.st_mtime,
-                  Status.st_uid, Status.st_gid, Status.st_size);
+      file_status(Type, Perms, Status.st_dev, Status.st_ino, Status.st_atime,
+                  Status.st_mtime, Status.st_uid, Status.st_gid,
+                  Status.st_size);
 
   return std::error_code();
 }
Index: lib/Support/Windows/Path.inc
===================================================================
--- lib/Support/Windows/Path.inc
+++ lib/Support/Windows/Path.inc
@@ -151,6 +151,16 @@
   return UniqueID(VolumeSerialNumber, FileID);
 }
 
+TimeValue file_status::getLastAccessedTime() const {
+  ULARGE_INTEGER UI;
+  UI.LowPart = LastAccessedTimeLow;
+  UI.HighPart = LastAccessedTimeHigh;
+
+  TimeValue Ret;
+  Ret.fromWin32Time(UI.QuadPart);
+  return Ret;
+}
+
 TimeValue file_status::getLastModificationTime() const {
   ULARGE_INTEGER UI;
   UI.LowPart = LastWriteTimeLow;
@@ -327,13 +337,15 @@
 
 bool equivalent(file_status A, file_status B) {
   assert(status_known(A) && status_known(B));
-  return A.FileIndexHigh      == B.FileIndexHigh &&
-         A.FileIndexLow       == B.FileIndexLow &&
-         A.FileSizeHigh       == B.FileSizeHigh &&
-         A.FileSizeLow        == B.FileSizeLow &&
-         A.LastWriteTimeHigh  == B.LastWriteTimeHigh &&
-         A.LastWriteTimeLow   == B.LastWriteTimeLow &&
-         A.VolumeSerialNumber == B.VolumeSerialNumber;
+  return A.FileIndexHigh         == B.FileIndexHigh &&
+         A.FileIndexLow          == B.FileIndexLow &&
+         A.FileSizeHigh          == B.FileSizeHigh &&
+         A.FileSizeLow           == B.FileSizeLow &&
+         A.LastAccessedTimeHigh  == B.LastAccessedTimeHigh &&
+         A.LastAccessedTimeLow   == B.LastAccessedTimeLow &&
+         A.LastWriteTimeHigh     == B.LastWriteTimeHigh &&
+         A.LastWriteTimeLow      == B.LastWriteTimeLow &&
+         A.VolumeSerialNumber    == B.VolumeSerialNumber;
 }
 
 std::error_code equivalent(const Twine &A, const Twine &B, bool &result) {
@@ -404,7 +416,9 @@
                          ? file_type::directory_file
                          : file_type::regular_file;
     Result =
-        file_status(Type, Info.ftLastWriteTime.dwHighDateTime,
+        file_status(Type, Info.lpLastAccessTime.dwHighDateTime,
+                    Info.lpLastAccessTime.dwLowDateTime,
+                    Info.ftLastWriteTime.dwHighDateTime,
                     Info.ftLastWriteTime.dwLowDateTime,
                     Info.dwVolumeSerialNumber, Info.nFileSizeHigh,
                     Info.nFileSizeLow, Info.nFileIndexHigh, Info.nFileIndexLow);