Re: What exactly is our CRC algorithm?

On 25/03/15 18:24, Heikki Linnakangas wrote:
> On 03/25/2015 07:20 PM, Andres Freund wrote:
>> On 2015-03-25 19:18:51 +0200, Heikki Linnakangas wrote:
>>> Or better yet, a direct configure test to check if the
>>> intrinsic exists - that way we get to also use it on Intel compilers,
>>> which
>>> I believe also has the same intrinsics.
>>
>> Maybe I'm missing something, but configure isn't run for msvc?
>
> Good point. On MSVC, we use the pre-built pg_config.h.win32 file
> instead. There are already a couple of cases like this in it:
>
> /* Define to 1 if you have the `rint' function. */
> #if (_MSC_VER >= 1800)
> #define HAVE_RINT 1
> #endif
>
> I think we should do that for the CRC32 intrinsic too.
>

Yeah, 1500 being MSVC 2008. But I think there is little point in putting
it in pg_config.h.win32 when it's only going to be used in 2 places in
single header file.

Do you plan to commit this otherwise as is?

--
Petr Jelinek http://www.2ndQuadrant.com/
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