Output UTF-8-encoded characters as identifier characters into assembly

by default.

This is a behaviour configurable in the MCAsmInfo. I've decided to turn
it on by default in (possibly optimistic) hopes that most assemblers are
reasonably sane. If this proves a problem, switching to default seems
reasonable.

I'm not sure if this is the opportune place to test, but it seemed good
to make sure it was tested somewhere.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@154235 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/MC/MCAsmInfo.h

@@ -143,6 +143,10 @@ namespace llvm {
     /// symbol names.  This defaults to true.
     bool AllowPeriodsInName;
 
+    /// AllowUTF8 - This is true if the assembler accepts UTF-8 input.
+    // FIXME: Make this a more general encoding setting?
+    bool AllowUTF8;
+
     //===--- Data Emission Directives -------------------------------------===//
 
     /// ZeroDirective - this should be set to the directive used to get some
@@ -485,6 +489,9 @@ namespace llvm {
     bool doesAllowPeriodsInName() const {
       return AllowPeriodsInName;
     }
+    bool doesAllowUTF8() const {
+      return AllowUTF8;
+    }
     const char *getZeroDirective() const {
       return ZeroDirective;
     }