antonblanchard / crc32-vpmsum Goto Github PK

see https://bugzilla.redhat.com/show_bug.cgi?id=2297744
see https://tracker.ceph.com/issues/66950

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Ceph uses assembly files from https://github.com/antonblanchard/crc32-vpmsum
Update them to the newest versions, which fixes build with Clang.

Signed-off-by: Piotr Kubaj <[[email protected]](mailto:[email protected])>

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This comes from src/common/crc32c_ppc_fast_zero_asm.S, I assume. It's just broken, it needs to use TOC-relative access.
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How would I go about implementing the crc32_combine function? Any pointers in your implementation?

https://github.com/madler/zlib/blob/master/crc32.c#L372
local uLong crc32_combine_(crc1, crc2, len2)

The combination problem is this: given the existing crc32 checksums for two separate data buffers buf1 and buf2, what is the crc32() of the concatenated buf1+buf2?

Speed is not a concern here: two 32 bit ints combining in to one 32b int. The polynom math is difficult.

/root/Clibmouse/ClickHouse/src/Common/vec_crc32.c:110:10: fatal error: 'clang_workaround.h' file not found
#include "clang_workaround.h"

PS: I was able to compile crc32-vpmsm repo successfully.
copied vec_crc32.c and crc32_contants.g in my application src path.