It adds vectorized ChaCha20 implementation based on libgcrypt
cipher/chacha20-amd64-avx2.S. It is used only if AVX2 is supported
and enabled by the architecture.
As for generic implementation, the last step that XOR with the
input is omited. The final state register clearing is also
omitted.
On a Ryzen 9 5900X it shows the following improvements (using
formatted bench-arc4random data):
SSE MB/s
-----------------------------------------------
arc4random [single-thread] 704.25
arc4random_buf(16) [single-thread] 1018.17
arc4random_buf(32) [single-thread] 1315.27
arc4random_buf(48) [single-thread] 1449.36
arc4random_buf(64) [single-thread] 1511.16
arc4random_buf(80) [single-thread] 1539.48
arc4random_buf(96) [single-thread] 1571.06
arc4random_buf(112) [single-thread] 1596.16
arc4random_buf(128) [single-thread] 1613.48
-----------------------------------------------
AVX2 MB/s
-----------------------------------------------
arc4random [single-thread] 922.61
arc4random_buf(16) [single-thread] 1478.70
arc4random_buf(32) [single-thread] 2241.80
arc4random_buf(48) [single-thread] 2681.28
arc4random_buf(64) [single-thread] 2913.43
arc4random_buf(80) [single-thread] 3009.73
arc4random_buf(96) [single-thread] 3141.16
arc4random_buf(112) [single-thread] 3254.46
arc4random_buf(128) [single-thread] 3305.02
-----------------------------------------------
Checked on x86_64-linux-gnu.
It adds vectorized ChaCha20 implementation based on libgcrypt
cipher/chacha20-amd64-ssse3.S. It replaces the ROTATE_SHUF_2 (which
uses pshufb) by ROTATE2 and thus making the original implementation
SSE2.
As for generic implementation, the last step that XOR with the
input is omited. The final state register clearing is also
omitted.
On a Ryzen 9 5900X it shows the following improvements (using
formatted bench-arc4random data):
GENERIC MB/s
-----------------------------------------------
arc4random [single-thread] 443.11
arc4random_buf(16) [single-thread] 552.27
arc4random_buf(32) [single-thread] 626.86
arc4random_buf(48) [single-thread] 649.81
arc4random_buf(64) [single-thread] 663.95
arc4random_buf(80) [single-thread] 674.78
arc4random_buf(96) [single-thread] 675.17
arc4random_buf(112) [single-thread] 680.69
arc4random_buf(128) [single-thread] 683.20
-----------------------------------------------
SSE MB/s
-----------------------------------------------
arc4random [single-thread] 704.25
arc4random_buf(16) [single-thread] 1018.17
arc4random_buf(32) [single-thread] 1315.27
arc4random_buf(48) [single-thread] 1449.36
arc4random_buf(64) [single-thread] 1511.16
arc4random_buf(80) [single-thread] 1539.48
arc4random_buf(96) [single-thread] 1571.06
arc4random_buf(112) [single-thread] 1596.16
arc4random_buf(128) [single-thread] 1613.48
-----------------------------------------------
Checked on x86_64-linux-gnu.
Adhemerval Zanella Netto