Add support for coldcc to clang

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175912 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGCall.cpp b/lib/CodeGen/CGCall.cpp
index 9fd31fe..f2c2d0a 100644
--- a/lib/CodeGen/CGCall.cpp
+++ b/lib/CodeGen/CGCall.cpp
@@ -37,6 +37,7 @@
 static unsigned ClangCallConvToLLVMCallConv(CallingConv CC) {
   switch (CC) {
   default: return llvm::CallingConv::C;
+  case CC_Cold: return llvm::CallingConv::Cold;
   case CC_X86StdCall: return llvm::CallingConv::X86_StdCall;
   case CC_X86FastCall: return llvm::CallingConv::X86_FastCall;
   case CC_X86ThisCall: return llvm::CallingConv::X86_ThisCall;
@@ -135,6 +136,9 @@
 
 static CallingConv getCallingConventionForDecl(const Decl *D) {
   // Set the appropriate calling convention for the Function.
+  if (D->hasAttr<ColdCCAttr>())
+    return CC_Cold;
+
   if (D->hasAttr<StdCallAttr>())
     return CC_X86StdCall;