StarterWare sys_arch.c coding question

sys_arch.c:

/**
 * This function is used to lock access to critical sections when lwipopt.h
 * defines SYS_LIGHTWEIGHT_PROT. It disables interrupts and returns a value
 * indicating the interrupt enable state when the function entered. This
 * value must be passed back on the matching call to sys_arch_unprotect().
 *
 * @return the interrupt level when the function was entered.
 */
sys_prot_t
sys_arch_protect(void)
{
  sys_prot_t status;
  status = (IntMasterStatusGet() & 0xFF);

  IntMasterIRQDisable();
  return status;
}

interrupt.c:

/**
 * \brief   Returns the status of the interrupts FIQ and IRQ.
 *
 * \param    None
 *
 * \return   Status of interrupt as in CPSR.
 *
 *  Note: This function call shall be done only in previleged mode of ARM
 **/
unsigned int IntMasterStatusGet(void)
{
    return CPUIntStatus();
}

cpu.c:
/*
**
** Wrapper function for the IRQ status
**
*/
__asm("    .sect \".text:CPUIntStatus\"\n"
          "    .clink\n"
          "    .global CPUIntStatus\n"
          "CPUIntStatus:\n"
          "    mrs     r0, CPSR \n"
          "    and     r0, r0, #0xC0\n"
          "    bx      lr");

Since I think the "and" instruction is zero-extended to 32 bits, then I am not sure what the "& 0xFF" does in sys_arch_protect().

btw: the comment above CPUIntStatus() says "IRQ" when I think it should say "FIQ and IRQ".