Avoid __popcnt64 on MSVC Windows 32-bit platform#87
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vlasky
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__popcnt64 intrinsic is not available on 32-bit Windows. Split u64 into two u32 values and use __popcnt on each half.
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The `__popcnt64` intrinsic isn't supported on 32-bit Windows, so `__popcnt` should be used instead.
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The
__popcnt64intrinsic isn't supported on 32-bit Windows, so__popcntshould be used instead.See also https://learn.microsoft.com/en-us/cpp/intrinsics/popcnt16-popcnt-popcnt64?view=msvc-170.
IMO, ideally we should use
stdc_count_ones(see here and WG14 N3220). But it will take a long long while until C23 will become popular enough.