This results in improved codegen for half libcalls on soft ABIs, and this logic will kick in for bf16 on soft ABIs as well. I don't think there's an existing hook for checking if we're on a soft ABI (perhaps I missed it?) and this patch doesn't add one, though there'd be an argument for doing so even if this is the only user.

This results in improved codegen for half libcalls on soft ABIs, and this logic will kick in for bf16 on soft ABIs as well. Adds a RISCVSubtarget helper method for determining if a soft FP ABI is being targeted (future bf16 related patches make use of this).

This results in improved codegen for half libcalls on soft ABIs, and this logic will kick in for bf16 on soft ABIs as well. I don't think there's an existing hook for checking if we're on a soft ABI (perhaps I missed it?) and this patch doesn't add one, though there'd be an argument for doing so even if this is the only user. Adds a RISCVSubtarget helper method for determining if a soft FP ABI is being targeted (future bf16 related patches make use of this).