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Can't register.set PC. And getting ERROR(CMM26-TAD17) then.

RoyC

Hi,

I tried to set PC with register.set like this in my .cmm file.

    register.set PC 0x80000000

But I got error code after sourcing my .cmm script.

- - -

ERROR(CMM26-TAD17):
! Failed to set the register PC(PC) to 0x80000000
! Register PC is an unsupported size (32)

- - -

Why is it an unsupported size?
I can't understand which setting goes wrong?

Thanks.

  • +1 Arm Employee Badge

    I guess you are connecting to an Armv8-A (Cortex-Axx) processor.

    On AArch64 processors, the PC is 64-bits wide, but the value 0x80000000 here in your register.set command is being treated as a 32-bit quantity.  You can resolve this by adding an explicit cast, e.g:
    register.set PC (long)0x80000000

    The same applies to the general purpose registers X0-X29, LR & SP.
    By contrast, W0-W30 are 32-bits wide, so you can use, e.g.:
    register.set W0 0x80000000

    Hope this helps

    Stephen

  • 0 in reply to Stephen Theobald

    Thanks.

    It works correctly with (long).
    It's also work with 0x80000000L.