Implement the no_split_stack attribute.

This is a GNU attribute that allows split stacks to be turned off on a
per-function basis.

Differential Revision: http://reviews.llvm.org/D3817

llvm-svn: 209167
diff --git a/clang/lib/Sema/SemaDeclAttr.cpp b/clang/lib/Sema/SemaDeclAttr.cpp
index 2e97a8a..b7c1d5d 100644
--- a/clang/lib/Sema/SemaDeclAttr.cpp
+++ b/clang/lib/Sema/SemaDeclAttr.cpp
@@ -4180,6 +4180,9 @@
   case AttributeList::AT_NoCommon:
     handleSimpleAttribute<NoCommonAttr>(S, D, Attr);
     break;
+  case AttributeList::AT_NoSplitStack:
+    handleSimpleAttribute<NoSplitStackAttr>(S, D, Attr);
+    break;
   case AttributeList::AT_NonNull:
     if (ParmVarDecl *PVD = dyn_cast<ParmVarDecl>(D))
       handleNonNullAttrParameter(S, PVD, Attr);