[ms-cxxabi] Use inalloca on win32 when passing non-trivial C++ objects

When a non-trivial parameter is present, clang now gathers up all the
parameters that lack inreg and puts them into a packed struct.  MSVC
always aligns each parameter to 4 bytes and no more, so this is a pretty
simple struct to lay out.

On win64, non-trivial records are passed indirectly.  Prior to this
change, clang was incorrectly using byval on win64.

I'm able to self-host a working clang with this change and additional
LLVM patches.

Reviewers: rsmith

Differential Revision: http://llvm-reviews.chandlerc.com/D2636

llvm-svn: 200597

1 files changed, 6 insertions, 3 deletions

diff --git a/clang/test/CodeGenCXX/copy-constructor-elim.cpp b/clang/test/CodeGenCXX/copy-constructor-elim.cpp
index ad3a87b9d5f..8e9bee97377 100644
--- a/clang/test/CodeGenCXX/copy-constructor-elim.cpp
+++ b/clang/test/CodeGenCXX/copy-constructor-elim.cpp
@@ -1,6 +1,9 @@
-// RUN: %clang_cc1 -emit-llvm -o %t %s
-// RUN: not grep "_ZN1CC1ERK1C" %t
-// RUN: not grep "_ZN1SC1ERK1S" %t
+// RUN: %clang_cc1 -triple %itanium_abi_triple -emit-llvm -o - %s | FileCheck %s -check-prefix=CHECK
+// RUN: %clang_cc1 -triple %ms_abi_triple -emit-llvm -o - %s | FileCheck %s -check-prefix MS
+// CHECK-NOT: _ZN1CC1ERK1C
+// CHECK-NOT: _ZN1SC1ERK1S
+// MS-NOT: ?0C@@QAE@ABV0
+// MS-NOT: ?0S@@QAE@ABV0
 
 extern "C" int printf(...);