30.3.2.1. ARMv8 aarch64 STR instruction
PC-relative STR is not possible in aarch64.
For LDR it works as in aarch32.
As a result, it is not possible to load from the literal pool for STR.
Example: userland/arch/aarch64/str.S
This can be seen from ARMv8 architecture reference manual C3.2.1 "Load/Store register": LDR simply has on extra PC encoding that STR does not.