Add attributes for preserve_mostcc/preserve_allcc calling conventions to the C/C++ front-end

Till now, preserve_mostcc/preserve_allcc calling convention attributes were only
available at the LLVM IR level. This patch adds attributes for
preserve_mostcc/preserve_allcc calling conventions to the C/C++ front-end.

The code was mostly written by Juergen Ributzka.
I just added support for the AArch64 target and tests.

Differential Revision: http://reviews.llvm.org/D18025

llvm-svn: 263647

1 files changed, 8 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/CGCall.cpp b/clang/lib/CodeGen/CGCall.cpp
index 7fb301c8c36..5e10f26ceb6 100644
--- a/clang/lib/CodeGen/CGCall.cpp
+++ b/clang/lib/CodeGen/CGCall.cpp
@@ -57,6 +57,8 @@ static unsigned ClangCallConvToLLVMCallConv(CallingConv CC) {
   case CC_X86VectorCall: return llvm::CallingConv::X86_VectorCall;
   case CC_SpirFunction: return llvm::CallingConv::SPIR_FUNC;
   case CC_SpirKernel: return llvm::CallingConv::SPIR_KERNEL;
+  case CC_PreserveMost: return llvm::CallingConv::PreserveMost;
+  case CC_PreserveAll: return llvm::CallingConv::PreserveAll;
   }
 }
 
@@ -187,6 +189,12 @@ static CallingConv getCallingConventionForDecl(const Decl *D, bool IsWindows) {
   if (D->hasAttr<SysVABIAttr>())
     return IsWindows ? CC_X86_64SysV : CC_C;
 
+  if (D->hasAttr<PreserveMostAttr>())
+    return CC_PreserveMost;
+
+  if (D->hasAttr<PreserveAllAttr>())
+    return CC_PreserveAll;
+
   return CC_C;
 }