generate an exception when jumping to a non-aligned (4-bit alignment) instruction

[benjamin051000]

From unpriv page 23:

An instruction-address-misaligned exception is generated on a taken branch or unconditional jump if the target address is not IALIGN-bit aligned.
This exception is reported on the branch or jump instruction, not on the target instruction. No
instruction-address-misaligned exception is generated for a conditional branch that is not taken.

IALIGN=32 in the base ISA.

[benjamin051000]

Instruction-address-misaligned exceptions are reported on the branch or jump that would
cause instruction misalignment to help debugging, and to simplify hardware design for
systems with IALIGN=32, where these are the only places where misalignment can occur.