Implement ARM pcs attribute. Basically it's another way of calling convention selection (AAPCS or
AAPCS+VFP), similar to fastcall / stdcall / whatevercall seen on x86.

In particular, all library functions should always be AAPCS regardless of floating point ABI used.

llvm-svn: 129534
diff --git a/clang/lib/AST/DumpXML.cpp b/clang/lib/AST/DumpXML.cpp
index 93ae1e3..8355b2d 100644
--- a/clang/lib/AST/DumpXML.cpp
+++ b/clang/lib/AST/DumpXML.cpp
@@ -911,6 +911,8 @@
     case CC_X86StdCall: return set("cc", "x86_stdcall");
     case CC_X86ThisCall: return set("cc", "x86_thiscall");
     case CC_X86Pascal: return set("cc", "x86_pascal");
+    case CC_AAPCS: return set("cc", "aapcs");
+    case CC_AAPCS_VFP: return set("cc", "aapcs_vfp");
     }
   }