A64 instruction set
A64 instructions are 32 bits wide.
ARMv8 introduces a new set of 32-bit instructions called A64, with new encodings and assembly language. A64 is only available when the processor is in AArch64 state. It provides similar functionality to the A32 and T32 instruction sets, but gives access to a larger virtual address space, and has some other changes, including reduced conditionality.
ARMv8 also defines an optional Crypto Extension. This extension provides cryptographic and hash instructions in the A64 instruction set.