[PATCH] [AArch64] Add support for the .inst directive.

[Tim Northover]

Hi Chad,

I think most of this looks fine. Just a couple of comments:

================
Comment at: lib/Target/AArch64/MCTargetDesc/AArch64ELFStreamer.cpp:50-51
@@ +49,4 @@
+  formatted_raw_ostream &OS;
+  MCInstPrinter &InstPrinter;
+  bool IsVerboseAsm;
+
----------------
These seem to be unused.

================
Comment at: test/MC/AArch64/inst-directive.s:1-2
@@ +1,3 @@
+// RUN: llvm-mc %s -triple=aarch64-none-linux-gnu -filetype=asm -o - \
+// RUN:   | FileCheck %s --check-prefix=CHECK-ASM
+// RUN: llvm-mc %s -triple=aarch64-none-linux-gnu -filetype=obj -o - \
----------------
This looks like it's going to silently eat .inst directives on MachO. I don't think that's a good idea.

http://reviews.llvm.org/D5891