Current Program Status Register
The Current Program Status Register (CPSR) holds the same program status flags as the APSR, and some additional information.
The CPSR holds:
The APSR flags.
The processor mode.
The interrupt disable flags.
The instruction set state (ARM, Thumb, ThumbEE, or Jazelle®).
The endianness state (on ARMv4T and later).
The execution state bits for the IT block (on ARMv6T2 and later).
The execution state bits control conditional execution in the IT block.
Only the APSR flags are accessible in all modes. ARM deprecates using an
MSR instruction to change the endianness bit (E) of the CPSR, in any
SETEND is the preferred instruction to write to the E bit.
The execution state bits for the IT block (IT[1:0]), Jazelle
bit (J), and Thumb bit (T) can be accessed by
in Debug state.