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Rasmus Villemoes
89c1e79eb3
The macro BITMAP_LAST_WORD_MASK can be implemented without a conditional, which will generally lead to slightly better generated code (221 bytes saved for allmodconfig-GCOV_KERNEL, ~2k with GCOV_KERNEL). As a small bonus, this also ensures that the nbits parameter is expanded exactly once. In BITMAP_FIRST_WORD_MASK, if start is signed gcc is technically allowed to assume it is positive (or divisible by BITS_PER_LONG), and hence just do the simple mask. It doesn't seem to use this, and even on an architecture like x86 where the shift only depends on the lower 5 or 6 bits, and these bits are not affected by the signedness of the expression, gcc still generates code to compute the C99 mandated value of start % BITS_PER_LONG. So just use a mask explicitly, also for consistency with BITMAP_LAST_WORD_MASK. Signed-off-by: Rasmus Villemoes <[email protected]> Cc: Tejun Heo <[email protected]> Reviewed-by: George Spelvin <[email protected]> Cc: Yury Norov <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>