Re: circuit's name
In the case of simple current mirror mp11 pmos always works in saturation because vdg=0<Vtp. Vdp11 drain voltage is defined by current and size of M11.
If Vdp goes too low (small m11 or high m11 current) it can limit maximal input voltage to Vdd-Vsg11+Vtn < Vdd (input transistor goes in saturation).
Vgs13 makes that pmos is always in triode region, because Vdg=Vgs13>Vtp.
In this case vdp11 and input voltage are not limited and can go up to Vdd.