3.6.2. Action on leaving an exception

On completion, the exception handler:

  1. Moves the Link Register, minus an offset where appropriate, to the PC. The offset varies depending on the type of exception.

  2. Copies the SPSR back to the CPSR.

  3. Clears the interrupt disable flags, if they were set on entry.


An explicit switch back to THUMB state is never needed, because restoring the CPSR from the SPSR automatically sets the T bit to the value it held immediately prior to the exception.

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