Is it
MOVS pc, r14
or
SUBS pc, r14, #4
This is written in the ARMDEN0013D. but in the table it says next instruction whereas the SUBS pc, r14, #4 means the instruction which was interrupted.
Yes it does make sense now. The preferred return address is that of the next instruction. And we add +4 so pc points to 8 bytes ahead, which it is supposed to since pc always points to instruction 8 bytes ahead.
when irq/fiq happens, that is the instruction that is interrupted.