4 ms·
The C extension is that, an extension. A RISC-V core with the C extension should still support the long encoding as well. There is no 16-bit variant specified,
by bpye 5y ago
The C extension is that, an extension. A RISC-V core with the C extension should still support the long encoding as well. There is no 16-bit variant specified, only 32, 64 and 128.
There is an E version of the ISA with a reduced register set, but this is a separate thing.
- brucehoult 5y agoYou are mixing up integer register size and instruction length. RISC-V has variants with 32 bit, 64 bit, or (not yet fully specified or implemented) 128 bit registers. RISC-V has instructions of length 32 bits and, optionally but almost universally, 16 bit length.