Compute CRC32C on ARM using the Crypto Extension where available
In similar vein to commit 3c6e8c123, the ARMv8 cryptography extension
has 64x64 -> 128-bit carryless multiplication instructions suitable
for computing CRC. This was tested to be around twice as fast as
scalar CRC instructions for longer inputs.
We now do a runtime check, even for builds that target "armv8-a+crc",
but those builds can still use a direct call for constant inputs,
which we assume are short.
As for x86, the MIT-licensed implementation was generated with the
"generate" program from
https://github.com/corsix/fast-crc32/
Reviewed-by: Nathan Bossart <nathandbossart@gmail.com>
Discussion: https://postgr.es/m/CANWCAZaKhE+RD5KKouUFoxx1EbUNrNhcduM1VQ=DkSDadNEFng@mail.gmail.com
Branch
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master
Details
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https://git.postgresql.org/pg/commitdiff/fbc57f2bc2ee498958a4c5326002af39dd99c90b
Modified Files
--------------
config/c-compiler.m4 | 38 +++++++++++
configure | 64 ++++++++++++++++++-
configure.ac | 13 +++-
meson.build | 33 ++++++++++
src/include/pg_config.h.in | 3 +
src/include/port/pg_crc32c.h | 22 +++++--
src/port/meson.build | 1 +
src/port/pg_crc32c_armv8.c | 128 ++++++++++++++++++++++++++++++++++++++
src/port/pg_crc32c_armv8_choose.c | 38 ++++++++++-
9 files changed, 329 insertions(+), 11 deletions(-)