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Peter Maydell
33eff5c84d
In of_dpa_mask2prefix() we do "(2 << i)" for a loop where i can go up to 31. At i == 31 we shift off the top end of an integer. This doesn't actually calculate the wrong value in practice, because we calculate 0 - 1 which is the 0xffffffff mask we wanted (and for QEMU shifting off the top of a signed integer is not UB); but it makes Coverity complain. We could fix this simply by using "2ULL" (where the "(2ULL << i) - 1" expression also evaluates to 0xffffffff for i == 31), but in fact this function is a slow looping implementation of counting the number of trailing zeroes in the (network-order) input mask: 0bxxxxxxxxx1 => 32 0bxxxxxxxx10 => 31 0bxxxxxxx100 => 30 ... 0bx100000000 => 2 0b1000000000 => 1 0b0000000000 => 0 Replace the implementation with 32 - ctz32(). Coverity: CID 1547602 Suggested-by: Philippe Mathieu-Daudé <philmd@linaro.org> Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> Message-id: 20251016145407.781978-1-peter.maydell@linaro.org