[openssl/openssl] b1b214: Acceleration of chacha20 on aarch64 by SVE

[pauli]

  Branch: refs/heads/master
  Home:   https://github.openssl.org/openssl/openssl
  Commit: b1b2146ded9ce5a84c62f30c6c4a922b449f6c90
      https://github.openssl.org/openssl/openssl/commit/b1b2146ded9ce5a84c62f30c6c4a922b449f6c90
  Author: Daniel Hu <Daniel.Hu at arm.com>
  Date:   2022-05-03 (Tue, 03 May 2022)

  Changed paths:
    M crypto/arm64cpuid.pl
    M crypto/arm_arch.h
    M crypto/armcap.c
    A crypto/chacha/asm/chacha-armv8-sve.pl
    M crypto/chacha/asm/chacha-armv8.pl
    M crypto/chacha/build.info

  Log Message:
  -----------
  Acceleration of chacha20 on aarch64 by SVE

This patch accelerates chacha20 on aarch64 when Scalable Vector Extension
(SVE) is supported by CPU. Tested on modern micro-architecture with
256-bit SVE, it has the potential to improve performance up to 20%

The solution takes a hybrid approach. SVE will handle multi-blocks that fit
the SVE vector length, with Neon/Scalar to process any tail data

Test result:
With SVE
type            1024 bytes   8192 bytes  16384 bytes
ChaCha20        1596208.13k  1650010.79k  1653151.06k

Without SVE (by Neon/Scalar)
type            1024 bytes   8192 bytes  16384 bytes
chacha20        1355487.91k  1372678.83k  1372662.44k

The assembly code has been reviewed internally by
ARM engineer Fangming.Fang at arm.com

Signed-off-by: Daniel Hu <Daniel.Hu at arm.com>

Reviewed-by: Tomas Mraz <tomas at openssl.org>
Reviewed-by: Paul Dale <pauli at openssl.org>
(Merged from https://github.com/openssl/openssl/pull/17916)