[LLVMdev] question on code in PointerIntPair.h

[Maurizio Vitale]

around line 45 a bitmask is computed as:

    PointerBitMask =
      ~(uintptr_t)(((intptr_t)1 << PtrTraits::NumLowBitsAvailable)-1),

my question is why is the shift performed on intptr_t? Wouldn't the
following be ok?
          
    PointerBitMask =
      ~(((uintptr_t)1 << PtrTraits::NumLowBitsAvailable)-1),

Thanks in advance,

       Maurizio