Mark ARM subtarget features that are available for the assembler.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117929 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ARM/AsmParser/ARMAsmParser.cpp b/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
index fe46a04..0f1b2e2 100644
--- a/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
+++ b/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
@@ -92,7 +92,11 @@
 
 public:
   ARMAsmParser(const Target &T, MCAsmParser &_Parser, TargetMachine &_TM)
-    : TargetAsmParser(T), Parser(_Parser), TM(_TM) {}
+    : TargetAsmParser(T), Parser(_Parser), TM(_TM) {
+      // Initialize the set of available features.
+      setAvailableFeatures(ComputeAvailableFeatures(
+          &TM.getSubtarget<ARMSubtarget>()));
+    }
 
   virtual bool ParseInstruction(StringRef Name, SMLoc NameLoc,
                                 SmallVectorImpl<MCParsedAsmOperand*> &Operands);