Add overflow-safe math inline functions for unsigned integers Similarly to the signed versions added in 4d6ad31, this adds a set of inline functions for overflow checks with unsigned integers, including uint16, uint32 and uint64. This relies on compiler built-in overflow checks by default if available. The behavior of unsigned integers is well-defined so the fallback implementations checks are simple for additions and subtractions. Multiplications avoid division-based checks which are expensive if possible, still this can happen for uint64 if 128-bit integers are not available.
While on it, the code in common/int.h is reorganized to avoid too many duplicated comments. The new macros will be used in a follow-up patch. All thanks to Andres Freund for the input provided. Author: Fabien Coelho, Michael Paquier Discussion: https://postgr.es/m/[email protected] Branch ------ master Details ------- https://git.postgresql.org/pg/commitdiff/7dedfd22b79822b7f4210e6255b672ea82db6678 Modified Files -------------- src/include/common/int.h | 242 +++++++++++++++++++++++++++++++++++++++-------- 1 file changed, 203 insertions(+), 39 deletions(-)
