Merge #12770: Use explicit casting in cuckoocache's compute_hashes(...) to clarify integer conversion

9142dfea81 Use explicit casting in cuckoocache's compute_hashes(...) to clarify integer conversion (practicalswift)

Pull request description:

  Use explicit casting in cuckoocache's `compute_hashes(...)` to clarify integer conversion.

  I discussed this code with the code's author @JeremyRubin who suggested patching it to avoid any confusion.

  At least one static analyzer incorrectly warns about a shift past bitwidth (UB) here, so this patch will help avoid confusion for human reviewers and static analyzers alike :-)

Tree-SHA512: 0419ee31b422d2ffedbd1a100688ec0ff5b0c1690d6d92592f638ca8db07a21a9650cb467923108c6f14a38d2bf07d6e6c85d2d1d4b7da53ffe6919f94f32655
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MarcoFalke 2018-04-09 08:06:08 -04:00 committed by pasta
parent cc5dd301ab
commit fc00189e5a
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@ -242,14 +242,14 @@ private:
*/
inline std::array<uint32_t, 8> compute_hashes(const Element& e) const
{
return {{(uint32_t)((hash_function.template operator()<0>(e) * (uint64_t)size) >> 32),
(uint32_t)((hash_function.template operator()<1>(e) * (uint64_t)size) >> 32),
(uint32_t)((hash_function.template operator()<2>(e) * (uint64_t)size) >> 32),
(uint32_t)((hash_function.template operator()<3>(e) * (uint64_t)size) >> 32),
(uint32_t)((hash_function.template operator()<4>(e) * (uint64_t)size) >> 32),
(uint32_t)((hash_function.template operator()<5>(e) * (uint64_t)size) >> 32),
(uint32_t)((hash_function.template operator()<6>(e) * (uint64_t)size) >> 32),
(uint32_t)((hash_function.template operator()<7>(e) * (uint64_t)size) >> 32)}};
return {{(uint32_t)(((uint64_t)hash_function.template operator()<0>(e) * (uint64_t)size) >> 32),
(uint32_t)(((uint64_t)hash_function.template operator()<1>(e) * (uint64_t)size) >> 32),
(uint32_t)(((uint64_t)hash_function.template operator()<2>(e) * (uint64_t)size) >> 32),
(uint32_t)(((uint64_t)hash_function.template operator()<3>(e) * (uint64_t)size) >> 32),
(uint32_t)(((uint64_t)hash_function.template operator()<4>(e) * (uint64_t)size) >> 32),
(uint32_t)(((uint64_t)hash_function.template operator()<5>(e) * (uint64_t)size) >> 32),
(uint32_t)(((uint64_t)hash_function.template operator()<6>(e) * (uint64_t)size) >> 32),
(uint32_t)(((uint64_t)hash_function.template operator()<7>(e) * (uint64_t)size) >> 32)}};
}
/* end