- Add subtarget feature -mattr=+db which determine whether an ARM cpu has the
  memory and synchronization barrier dmb and dsb instructions.
- Change instruction names to something more sensible (matching name of actual
  instructions).
- Added tests for memory barrier codegen.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110785 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ARM/ARMSubtarget.cpp b/lib/Target/ARM/ARMSubtarget.cpp
index 52913e9..db50c9f 100644
--- a/lib/Target/ARM/ARMSubtarget.cpp
+++ b/lib/Target/ARM/ARMSubtarget.cpp
@@ -42,6 +42,7 @@
   , HasFP16(false)
   , HasHardwareDivide(false)
   , HasT2ExtractPack(false)
+  , HasDataBarrier(false)
   , Pref32BitThumb(false)
   , stackAlignment(4)
   , CPUString("generic")