[PATCH] D35259: Complex Long Double classification In RegCall calling convention

[Reid Kleckner via Phabricator via cfe-commits]

rnk added a comment.

In https://reviews.llvm.org/D35259#805284, @erichkeane wrote:

> Oren discovered this miss to the original implementation.  I'd reviewed this internally quite a bit.
>
> The reason for the Win32ABI test is that MSVC 'long double' is actually small enough for SSE registers in this case.  I DO now (looking again, sorry Elizabeth) wonder if there is a better way to exclude extended-length LongDouble type?  Could we us the 'length' of it instead? @rnk : opinion?


Yeah, you can ask clang::TargetInfo for the format of most basic FP types. The code to do that looks like:

  &TI.getLongDoubleFormat() == &llvm::APFloat::x87DoubleExtended()

Any reason you can't just add that condition to isX86VectorTypeForVectorCall? I assume we don't want to pass x86_fp80s in SSE registers for vectorcall either, right? That would eliminate the need for the isRegCallReturnableHA helper and the IsWin32StructABI parameter, which is a poorly named variable.


https://reviews.llvm.org/D35259