crypto/sha512: optimize sha512 by removing function literal
crypto/sha512: optimize sha512 by removing function literal

The function 'block' called indirectly via function literal 'blockGeneric' prevents
'gc' performing an accurate escape analysis to its arguments, that will result in
unnecessary heap object allocation and GC cost.

Consistent performance improvement to sha512 and its dependency packages are
observed on various arm64 servers if eliminating the function literal, especially for
small-sized benchmarks.

A72:
========================================================================================================
name                                               old time/op    new time/op     delta
pkg:crypto/sha512 goos:linux goarch:arm64
Hash8Bytes-64                                        1.61µs ± 0%     1.37µs ± 0%   -14.99%  (p=0.000 n=8+9)
Hash1K-64                                            11.2µs ± 0%     10.9µs ± 0%    -2.41%  (p=0.000 n=8+10)
Hash8K-64                                            77.8µs ± 0%     77.5µs ± 0%    -0.44%  (p=0.002 n=10+10)
pkg:crypto/ecdsa goos:linux goarch:arm64
pkg:crypto/hmac goos:linux goarch:arm64
pkg:crypto/tls goos:linux goarch:arm64
HandshakeServer/RSA-64                                920µs ± 0%      919µs ± 0%    -0.10%  (p=0.035 n=10+9)
HandshakeServer/ECDHE-P256-RSA/TLSv13-64             1.32ms ± 1%     1.31ms ± 0%    -0.24%  (p=0.002 n=9+8)
HandshakeServer/ECDHE-P256-RSA/TLSv12-64             1.25ms ± 0%     1.25ms ± 0%    -0.07%  (p=0.040 n=9+9)
HandshakeServer/ECDHE-P256-ECDSA-P256/TLSv12-64       486µs ± 0%      485µs ± 0%    -0.19%  (p=0.000 n=9+10)
HandshakeServer/ECDHE-X25519-ECDSA-P256/TLSv13-64    1.01ms ± 0%     1.01ms ± 0%    -0.36%  (p=0.000 n=9+10)
HandshakeServer/ECDHE-X25519-ECDSA-P256/TLSv12-64     948µs ± 0%      947µs ± 0%    -0.11%  (p=0.001 n=10+10)
HandshakeServer/ECDHE-P521-ECDSA-P521/TLSv12-64      42.1ms ± 3%     42.5ms ± 2%    +0.77%  (p=0.010 n=8+8)
Throughput/MaxPacket/8MB/TLSv13-64                   46.9ms ± 9%     42.8ms ± 2%    -8.71%  (p=0.000 n=10+9)
Throughput/MaxPacket/64MB/TLSv13-64                   385ms ±17%      332ms ±18%   -13.64%  (p=0.002 n=10+10)
Throughput/DynamicPacket/2MB/TLSv12-64              39.1ms ±110%     17.2ms ±24%   -55.97%  (p=0.002 n=10+9)
Throughput/DynamicPacket/4MB/TLSv12-64               32.2ms ±22%     27.2ms ±40%   -15.69%  (p=0.029 n=10+10)
Throughput/DynamicPacket/4MB/TLSv13-64               27.4ms ±18%     24.9ms ±31%    -9.12%  (p=0.031 n=9+9)
Throughput/DynamicPacket/8MB/TLSv12-64               61.8ms ±32%     43.9ms ±18%   -28.93%  (p=0.000 n=10+9)
Throughput/DynamicPacket/8MB/TLSv13-64               49.4ms ±14%     45.7ms ±19%    -7.44%  (p=0.035 n=10+10)
Throughput/DynamicPacket/32MB/TLSv13-64               181ms ±13%      163ms ± 7%   -10.17%  (p=0.001 n=9+10)
Latency/MaxPacket/5000kbps/TLSv13-64                 37.2ms ±52%     30.8ms ± 0%   -17.21%  (p=0.017 n=10+9)
Latency/DynamicPacket/2000kbps/TLSv13-64             16.7ms ± 1%     16.6ms ± 0%    -0.39%  (p=0.002 n=8+10)
pkg:crypto/ed25519 goos:linux goarch:arm64
KeyGeneration-64                                      139µs ± 0%      139µs ± 0%    -0.45%  (p=0.000 n=9+10)
NewKeyFromSeed-64                                     139µs ± 0%      139µs ± 0%    -0.34%  (p=0.000 n=10+10)
Signing-64                                            144µs ± 0%      143µs ± 0%    -0.73%  (p=0.000 n=10+10)
Verification-64                                       410µs ± 0%      410µs ± 0%    -0.09%  (p=0.000 n=9+9)

[Geo mean]                                           9.81ms          9.59ms         -2.30%

name                                               old speed      new speed       delta
pkg:crypto/sha512 goos:linux goarch:arm64
Hash8Bytes-64                                      4.96MB/s ± 0%   5.84MB/s ± 0%   +17.60%  (p=0.000 n=7+9)
Hash1K-64                                          91.5MB/s ± 0%   93.7MB/s ± 0%    +2.47%  (p=0.000 n=8+10)
Hash8K-64                                           105MB/s ± 0%    106MB/s ± 0%    +0.45%  (p=0.001 n=10+10)
pkg:crypto/hmac goos:linux goarch:arm64
pkg:crypto/tls goos:linux goarch:arm64
Throughput/MaxPacket/8MB/TLSv13-64                  179MB/s ± 9%    196MB/s ± 2%    +9.31%  (p=0.000 n=10+9)
Throughput/MaxPacket/64MB/TLSv13-64                 176MB/s ±20%    203MB/s ±16%   +15.35%  (p=0.002 n=10+10)
Throughput/DynamicPacket/2MB/TLSv12-64             70.2MB/s ±82%  118.9MB/s ±45%   +69.30%  (p=0.005 n=10+10)
Throughput/DynamicPacket/4MB/TLSv12-64              132MB/s ±19%    159MB/s ±31%   +20.31%  (p=0.029 n=10+10)
Throughput/DynamicPacket/4MB/TLSv13-64              155MB/s ±16%    171MB/s ±24%   +10.26%  (p=0.031 n=9+9)
Throughput/DynamicPacket/8MB/TLSv12-64              141MB/s ±37%    192MB/s ±15%   +36.28%  (p=0.000 n=10+9)
Throughput/DynamicPacket/8MB/TLSv13-64              170MB/s ±12%    185MB/s ±17%    +8.46%  (p=0.035 n=10+10)
Throughput/DynamicPacket/32MB/TLSv13-64             186MB/s ±12%    206MB/s ± 6%   +10.96%  (p=0.001 n=9+10)

[Geo mean]                                          133MB/s         141MB/s         +6.04%

name                                               old alloc/op   new alloc/op    delta
pkg:crypto/ecdsa goos:linux goarch:arm64
SignP256-64                                          3.03kB ± 0%     2.67kB ± 1%   -11.71%  (p=0.000 n=10+9)
pkg:crypto/ed25519 goos:linux goarch:arm64
NewKeyFromSeed-64                                      352B ± 0%         0B       -100.00%  (p=0.000 n=10+10)
Signing-64                                           1.50kB ± 0%     0.45kB ± 0%   -70.21%  (p=0.000 n=10+10)

[Geo mean]                                           3.39kB          4.08kB        +20.24%

name                                               old allocs/op  new allocs/op   delta
pkg:crypto/ecdsa goos:linux goarch:arm64
SignP256-64                                            34.0 ± 0%       32.0 ± 0%    -5.88%  (p=0.000 n=10+10)
SignP384-64                                           14.5k ± 0%      14.5k ± 0%    -0.12%  (p=0.045 n=10+10)
pkg:crypto/ed25519 goos:linux goarch:arm64
NewKeyFromSeed-64                                      2.00 ± 0%       0.00       -100.00%  (p=0.000 n=10+10)
Signing-64                                             11.0 ± 0%        5.0 ± 0%   -54.55%  (p=0.000 n=10+10)

[Geo mean]                                             35.7            53.6        +50.15%

A57:
=========================================================================================================
name                                              old time/op    new time/op    delta
pkg:crypto/sha512 goos:linux goarch:arm64
Hash8Bytes-8                                        1.93µs ± 0%    1.69µs ± 0%   -12.37%  (p=0.000 n=10+10)
Hash1K-8                                            13.8µs ± 0%    13.5µs ± 0%    -2.01%  (p=0.000 n=10+10)
Hash8K-8                                            96.1µs ± 0%    95.7µs ± 0%    -0.35%  (p=0.000 n=10+8)
pkg:crypto/ecdsa goos:linux goarch:arm64
SignP256-8                                          14.9µs ± 4%    14.4µs ± 1%    -2.84%  (p=0.000 n=10+9)
pkg:crypto/hmac goos:linux goarch:arm64
HMACSHA256_1K-8                                     1.87µs ± 0%    1.86µs ± 0%    -0.55%  (p=0.000 n=9+10)
HMACSHA256_32-8                                      760ns ± 0%     756ns ± 0%    -0.54%  (p=0.001 n=10+10)
pkg:crypto/tls goos:linux goarch:arm64
HandshakeServer/RSA-8                               1.11ms ± 0%    1.12ms ± 0%    +0.35%  (p=0.001 n=9+10)
HandshakeServer/ECDHE-P256-RSA/TLSv13-8             1.63ms ± 0%    1.63ms ± 0%    -0.23%  (p=0.004 n=10+9)
HandshakeServer/ECDHE-P256-ECDSA-P256/TLSv13-8       694µs ± 0%     687µs ± 0%    -0.96%  (p=0.000 n=10+8)
HandshakeServer/ECDHE-P256-ECDSA-P256/TLSv12-8       607µs ± 0%     601µs ± 0%    -0.99%  (p=0.000 n=9+9)
HandshakeServer/ECDHE-X25519-ECDSA-P256/TLSv13-8    1.25ms ± 0%    1.25ms ± 0%    -0.24%  (p=0.015 n=10+10)
HandshakeServer/ECDHE-X25519-ECDSA-P256/TLSv12-8    1.16ms ± 0%    1.16ms ± 0%    -0.30%  (p=0.000 n=8+10)
Latency/MaxPacket/200kbps/TLSv12-8                   697ms ± 0%     697ms ± 0%    +0.01%  (p=0.029 n=10+10)
Latency/DynamicPacket/200kbps/TLSv13-8               140ms ± 0%     140ms ± 0%    +0.04%  (p=0.006 n=9+10)
pkg:crypto/ed25519 goos:linux goarch:arm64
NewKeyFromSeed-8                                     168µs ± 0%     168µs ± 0%    +0.04%  (p=0.001 n=9+10)
Signing-8                                            174µs ± 0%     173µs ± 0%    -0.26%  (p=0.000 n=10+10)
Verification-8                                       495µs ± 0%     494µs ± 0%    -0.10%  (p=0.000 n=9+9)

[Geo mean]                                          9.85ms         9.82ms         -0.36%

name                                              old speed      new speed      delta
pkg:crypto/sha512 goos:linux goarch:arm64
Hash8Bytes-8                                      4.15MB/s ± 0%  4.74MB/s ± 0%   +14.11%  (p=0.000 n=10+10)
Hash1K-8                                          74.3MB/s ± 0%  75.8MB/s ± 0%    +2.05%  (p=0.000 n=10+10)
Hash8K-8                                          85.3MB/s ± 0%  85.6MB/s ± 0%    +0.35%  (p=0.000 n=10+8)
pkg:crypto/hmac goos:linux goarch:arm64
HMACSHA256_1K-8                                    549MB/s ± 0%   552MB/s ± 0%    +0.56%  (p=0.000 n=9+10)
HMACSHA256_32-8                                   42.1MB/s ± 0%  42.3MB/s ± 1%    +0.53%  (p=0.001 n=10+10)
pkg:crypto/tls goos:linux goarch:arm64

[Geo mean]                                         138MB/s        139MB/s         +0.54%

name                                              old alloc/op   new alloc/op   delta
pkg:crypto/ecdsa goos:linux goarch:arm64
SignP256-8                                          2.99kB ± 0%    2.64kB ± 0%   -11.77%  (p=0.000 n=10+10)
pkg:crypto/ed25519 goos:linux goarch:arm64
NewKeyFromSeed-8                                      352B ± 0%        0B       -100.00%  (p=0.000 n=10+10)
Signing-8                                           1.50kB ± 0%    0.45kB ± 0%   -70.21%  (p=0.000 n=10+10)

[Geo mean]                                          3.34kB         4.01kB        +20.04%

name                                              old allocs/op  new allocs/op  delta
pkg:crypto/ecdsa goos:linux goarch:arm64
SignP256-8                                            34.0 ± 0%      32.0 ± 0%    -5.88%  (p=0.000 n=10+10)
pkg:crypto/ed25519 goos:linux goarch:arm64
NewKeyFromSeed-8                                      2.00 ± 0%      0.00       -100.00%  (p=0.000 n=10+10)
Signing-8                                             11.0 ± 0%       5.0 ± 0%   -54.55%  (p=0.000 n=10+10)

[Geo mean]                                            35.7           53.6        +50.17%

Change-Id: Ibbda2d9bdff4eea4f611d4590abceb8764c44f2e
Reviewed-on: https://go-review.googlesource.com/c/go/+/211617
Reviewed-by: Filippo Valsorda <4f40cda291c5f9634e1affd3db44947af61f705c@golang.org>
Run-TryBot: Filippo Valsorda <4f40cda291c5f9634e1affd3db44947af61f705c@golang.org>
TryBot-Result: Gobot Gobot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>

nawawi/go,CAFxX/go,CAFxX/go,akutz/go,akutz/go,nawawi/go,golang/go,CAFxX/go,akutz/go,golang/go,CAFxX/go,golang/go,CAFxX/go,CAFxX/go,cloudflare/go,cloudflare/go,akutz/go,golang/go,akutz/go,nawawi/go,golang/go,golang/go,cloudflare/go,nawawi/go,golang/go,CAFxX/go,cloudflare/go,cloudflare/go,akutz/go,cloudflare/go,cloudflare/go,nawawi/go,CAFxX/go,akutz/go,nawawi/go,nawawi/go,akutz/go,nawawi/go,golang/go,cloudflare/go