Add argmemonly attribute.

This change adds new attribute called "argmemonly". Function marked with this attribute can only access memory through it's argument pointers. This attribute directly corresponds to the "OnlyAccessesArgumentPointees" ModRef behaviour in alias analysis.

Differential Revision: http://reviews.llvm.org/D10398

llvm-svn: 241979

llvm/lib/Bitcode/Writer/BitcodeWriter.cpp

@@ -162,6 +162,8 @@ static uint64_t getAttrKindEncoding(Attribute::AttrKind Kind) {
     return bitc::ATTR_KIND_ALIGNMENT;
   case Attribute::AlwaysInline:
     return bitc::ATTR_KIND_ALWAYS_INLINE;
+  case Attribute::ArgMemOnly:
+    return bitc::ATTR_KIND_ARGMEMONLY;
   case Attribute::Builtin:
     return bitc::ATTR_KIND_BUILTIN;
   case Attribute::ByVal: