NaplesPURegisterInfo.td
From NaplesPU Documentation
The NuPlusRegisterInfo.td is used to define the nu+ hw registers and the nu+ register classes.
The registers definition is done creating two support classes NuPlusGPRReg and NuPlus64GPRReg. The first one is used to define 32-bits wide registers while the second is used to define 64-bits wide registers. We made this distinction because the hardware uses the same register for both 32 and 64 bits wide variables.