[cnvogel]

And if you need something like ~(byte << N) for any purpose there's still MVN (move-not).

     MVN r0, #0x10000000 ; ro = 0xefffffff

Oh, the joy :-).

[stephencanon]

CMN is the real gem. It's an endless source of bugs in the time between when compiler writers discover it and when they figure out how it actually sets flags. ARM would have done well to provide a "here's how you actually use this instruction" guide in the architecture reference manual.