tree 01eb3d1a091ef2e35fd2142061ca1efab0a1b590
parent aec89faa2e366e5cff501310771afaf16289c6ad
author Mark Adler <madler@alumni.caltech.edu> 1550461737 -0800
committer Mark Adler <madler@alumni.caltech.edu> 1550461737 -0800

Add use of the ARMv8 crc32 instructions when requested.

Define the macro Z_ARM_CRC32 at compile time to use the ARMv8
(aarch64) crc32x and crc32b instructions. This code does not check
for the presence of the crc32 instructions. Those instructions are
optional for ARMv8.0, though mandatory for ARMv8.1 and later. The
use of the crc32 instructions is about ten times as fast as the
software braided calculation of the CRC-32. This can noticeably
speed up the decompression of gzip streams.