[clang] [CIR] Cleanup support for C functions (PR #136854)

[Erich Keane via cfe-commits]

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@@ -71,6 +130,23 @@ static cir::CIRCallOpInterface emitCallLikeOp(CIRGenFunction &cgf,
   return builder.createCallOp(callLoc, directFuncOp);
 }
 
+const CIRGenFunctionInfo &
+CIRGenTypes::arrangeFreeFunctionType(CanQual<FunctionProtoType> fpt) {
+  SmallVector<CanQualType, 16> argTypes;
+  for (unsigned i = 0, e = fpt->getNumParams(); i != e; ++i)
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erichkeane wrote:

Is this not just a `llvm::copy(fpt->param_types(), std::back_inserter(argTypes))` ? 

https://github.com/llvm/llvm-project/pull/136854