Architecture support for Advanced SIMD
Advanced SIMD is an optional extension to the Arm®v8 and Armv7 architectures.
All Advanced SIMD instructions are available on systems that support Advanced SIMD. In A32, some of these instructions are also available on systems that implement the floating-point extension without Advanced SIMD. These are called shared instructions.
In AArch32 state, the Advanced SIMD register bank consists of thirty-two 64-bit registers, and smaller registers are packed into larger ones, as in Armv7.
In AArch64 state, the Advanced SIMD register bank includes thirty-two 128-bit registers and has a new register packing model.
NoteAdvanced SIMD and floating-point instructions share the same extension register bank.
Advanced SIMD instructions in A64 are closely based on VFPv4 and A32, but with new instruction mnemonics and some functional enhancements.