[ms-cxxabi] Add a new calling convention that swaps 'this' and 'sret'

MSVC always places the 'this' parameter for a method first.  The
implicit 'sret' pointer for methods always comes second.  We already
implement this for __thiscall by putting sret parameters on the stack,
but __cdecl methods require putting both parameters on the stack in
opposite order.

Using a special calling convention allows frontends to keep the sret
parameter first, which avoids breaking lots of assumptions in LLVM and
Clang.

Fixes PR15768 with the corresponding change in Clang.

Reviewers: ributzka, majnemer

Differential Revision: http://llvm-reviews.chandlerc.com/D2663

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200561 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Reid Kleckner
2014-01-31 17:41:22 +00:00
parent 0cb94d9adc
commit 65c98b9da4
10 changed files with 124 additions and 2 deletions
+1
View File
@@ -78,6 +78,7 @@ static void PrintCallingConv(unsigned cc, raw_ostream &Out) {
case CallingConv::X86_StdCall: Out << "x86_stdcallcc"; break;
case CallingConv::X86_FastCall: Out << "x86_fastcallcc"; break;
case CallingConv::X86_ThisCall: Out << "x86_thiscallcc"; break;
case CallingConv::X86_CDeclMethod:Out << "x86_cdeclmethodcc"; break;
case CallingConv::Intel_OCL_BI: Out << "intel_ocl_bicc"; break;
case CallingConv::ARM_APCS: Out << "arm_apcscc"; break;
case CallingConv::ARM_AAPCS: Out << "arm_aapcscc"; break;