[clang] [CIR] Upstream support for calling constructors (PR #143579)

[Andy Kaylor via cfe-commits]

================
@@ -141,6 +190,44 @@ arrangeFreeFunctionLikeCall(CIRGenTypes &cgt, CIRGenModule &cgm,
   return cgt.arrangeCIRFunctionInfo(retType, argTypes, required);
 }
 
+/// Arrange a call to a C++ method, passing the given arguments.
+///
+/// passProtoArgs indicates whether `args` has args for the parameters in the
+/// given CXXConstructorDecl.
+const CIRGenFunctionInfo &CIRGenTypes::arrangeCXXConstructorCall(
+    const CallArgList &args, const CXXConstructorDecl *d, CXXCtorType ctorKind,
+    bool passProtoArgs) {
+
+  // FIXME: Kill copy.
----------------
andykaylor wrote:

This is one of those comments that was brought over from classic codegen. It appears six times in both classic codegen and the CIR incubator codegen, always in conjunction with a call to arrangeLLVMFunctionInfo/arrangeCIRFunctionInfo. The problem is that one of the places it occurs (the static version of arrangeLLVMFunctionInfo/arrangeCIRFunctionInfo) takes a list of types from the caller but then appends additional types based on FunctionProtoType::getExtParameterInfos().

I definitely want to leave it alone for now. It may be a solvable problem, but the priority of solving it appears to be very low.

https://github.com/llvm/llvm-project/pull/143579