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LDM instruction and ^ suffix

Bruno Lavier
Prodigy 160 points

Hi,

In the ARM documentation about the LDM instruction and the ^suffix, we can read:

^ is an optional suffix, available in ARM state only. You must not use it in User mode or System
mode. It has the following purposes:
• If reglist contains the PC (R15), in addition to the normal multiple register transfer, the
SPSR is copied into the CPSR. This is for returning from exception handlers. Use this only
from exception modes.
• Otherwise, data is transferred into or out of the User mode registers instead of the current
mode registers.

It's quite confusing to me (especially "into or out of the User mode registers")

Are the following assertions OK (hypothesis : in supervisor mode when instruction is executed) ?

  1. LDMFD   SP!, {R0-R12, LR, PC}^
    SP is R13_svc?
    LR is R14_svc?

  2. LDMFD   SP!, {R0-R12, LR}^
    SP is R13_svc or R13_usr (R13) as PC is not in reglist?
    LR is R14_usr (R14) as PC is not in reglist ?

Thanks you