9.53.2.2 Register Names

The assembly syntax for a register file entry is the “short” name for a TIE register file followed by the index into that register file. For example, the general-purpose AR register file has a short name of a , so these registers are named a0 ... a15 . As a special feature, sp is also supported as a synonym for a1 . Additional registers may be added by processor configuration options and by designer-defined TIE extensions. An initial ‘ $ ’ character is optional in all register names.