The A64 manual says 1111 on a Bcc etc disassembles as NV but does the same as AL.
The ARM7TDMI manual says 1111 is reserved and don't use it. I don't know the actual behaviour.
Aha. The Welsh&Knaggs "ARM Book" says before ARMv3 NV meant NV. In ARMv3 and ARMv4 NV is unpredictable. And in ARMv5 NV is used to encode "various additional instructions that can only be executed unconditionally".
The A64 manual says 1111 on a Bcc etc disassembles as NV but does the same as AL.
The ARM7TDMI manual says 1111 is reserved and don't use it. I don't know the actual behaviour.
Aha. The Welsh&Knaggs "ARM Book" says before ARMv3 NV meant NV. In ARMv3 and ARMv4 NV is unpredictable. And in ARMv5 NV is used to encode "various additional instructions that can only be executed unconditionally".