cmd/compile/mips: intrinsify bits.RotateLeft32 on MIPS #45028

stffabi · 2021-03-15T15:48:53Z

This CL implements the ROTR & ROTRV instructions for
MIPS and MIPS64, which are mips32r2 instructions.

Additionally bits.RotateLeft32 is now instrinsic and will be
rewritten to ROTR during the SSA phase.

This brings roughly a 65-70% improvement on mipsle
code running Chacha20Poly1305 on a MT7688:

goos: linux
goarch: mipsle
pkg: golang.org/x/crypto/chacha20poly1305
name old time/op new time/op delta
Chacha20Poly1305/Open-16 56.2µs ±20% 38.5µs ±40% -31.45% (p=0.001 n=8+10)
Chacha20Poly1305/Seal-16 68.3µs ±49% 30.6µs ±13% -55.14% (p=0.000 n=10+10)
Chacha20Poly1305/Open-64 67.5µs ±22% 37.8µs ±19% -43.98% (p=0.000 n=9+9)
Chacha20Poly1305/Seal-64 64.7µs ±10% 37.6µs ± 8% -41.96% (p=0.000 n=9+8)
Chacha20Poly1305/Open-256 151µs ±13% 89µs ±20% -41.03% (p=0.000 n=9+10)
Chacha20Poly1305/Seal-256 148µs ±19% 93µs ±35% -37.15% (p=0.000 n=10+10)
Chacha20Poly1305/Open-1024 456µs ±16% 260µs ±23% -42.95% (p=0.000 n=10+10)
Chacha20Poly1305/Seal-1024 469µs ±14% 254µs ±15% -45.88% (p=0.000 n=10+9)
Chacha20Poly1305/Open-8192 3.59ms ±23% 1.94ms ±15% -45.86% (p=0.000 n=10+10)
Chacha20Poly1305/Seal-8192 3.47ms ±20% 2.03ms ±22% -41.60% (p=0.000 n=9+10)
Chacha20Poly1305/Open-16384 7.01ms ± 9% 4.22ms ±22% -39.89% (p=0.000 n=9+10)
Chacha20Poly1305/Seal-16384 7.43ms ±19% 4.23ms ±11% -43.04% (p=0.000 n=10+9)

name old speed new speed delta
Chacha20Poly1305/Open-16 258kB/s ±46% 431kB/s ±32% +67.05% (p=0.000 n=10+10)
Chacha20Poly1305/Seal-16 246kB/s ±35% 527kB/s ±13% +114.23% (p=0.000 n=10+10)
Chacha20Poly1305/Open-64 927kB/s ±31% 1664kB/s ±22% +79.50% (p=0.000 n=10+10)
Chacha20Poly1305/Seal-64 993kB/s ±10% 1709kB/s ± 8% +72.02% (p=0.000 n=9+8)
Chacha20Poly1305/Open-256 1.70MB/s ±13% 2.90MB/s ±18% +70.88% (p=0.000 n=9+10)
Chacha20Poly1305/Seal-256 1.74MB/s ±17% 2.81MB/s ±28% +61.16% (p=0.000 n=10+10)
Chacha20Poly1305/Open-1024 2.26MB/s ±15% 3.99MB/s ±20% +76.38% (p=0.000 n=10+10)
Chacha20Poly1305/Seal-1024 2.20MB/s ±13% 3.92MB/s ±32% +78.82% (p=0.000 n=10+10)
Chacha20Poly1305/Open-8192 2.31MB/s ±19% 4.24MB/s ±14% +83.72% (p=0.000 n=10+10)
Chacha20Poly1305/Seal-8192 2.30MB/s ±29% 4.09MB/s ±19% +77.66% (p=0.000 n=10+10)
Chacha20Poly1305/Open-16384 2.34MB/s ±10% 3.93MB/s ±19% +68.04% (p=0.000 n=9+10)
Chacha20Poly1305/Seal-16384 2.23MB/s ±17% 3.79MB/s ±23% +70.00% (p=0.000 n=10+10)

Fixes #39139

This CL implements the ROTR & ROTRV instructions for MIPS and MIPS64, which are mips32r2 instructions. Additionally bits.RotateLeft32 is now instrinsic and will be rewritten to ROTR during the SSA phase. This brings roughly a 65-70% improvement on mipsle code running Chacha20Poly1305 on a MT7688: goos: linux goarch: mipsle pkg: golang.org/x/crypto/chacha20poly1305 name old time/op new time/op delta Chacha20Poly1305/Open-16 56.2µs ±20% 38.5µs ±40% -31.45% (p=0.001 n=8+10) Chacha20Poly1305/Seal-16 68.3µs ±49% 30.6µs ±13% -55.14% (p=0.000 n=10+10) Chacha20Poly1305/Open-64 67.5µs ±22% 37.8µs ±19% -43.98% (p=0.000 n=9+9) Chacha20Poly1305/Seal-64 64.7µs ±10% 37.6µs ± 8% -41.96% (p=0.000 n=9+8) Chacha20Poly1305/Open-256 151µs ±13% 89µs ±20% -41.03% (p=0.000 n=9+10) Chacha20Poly1305/Seal-256 148µs ±19% 93µs ±35% -37.15% (p=0.000 n=10+10) Chacha20Poly1305/Open-1024 456µs ±16% 260µs ±23% -42.95% (p=0.000 n=10+10) Chacha20Poly1305/Seal-1024 469µs ±14% 254µs ±15% -45.88% (p=0.000 n=10+9) Chacha20Poly1305/Open-8192 3.59ms ±23% 1.94ms ±15% -45.86% (p=0.000 n=10+10) Chacha20Poly1305/Seal-8192 3.47ms ±20% 2.03ms ±22% -41.60% (p=0.000 n=9+10) Chacha20Poly1305/Open-16384 7.01ms ± 9% 4.22ms ±22% -39.89% (p=0.000 n=9+10) Chacha20Poly1305/Seal-16384 7.43ms ±19% 4.23ms ±11% -43.04% (p=0.000 n=10+9) name old speed new speed delta Chacha20Poly1305/Open-16 258kB/s ±46% 431kB/s ±32% +67.05% (p=0.000 n=10+10) Chacha20Poly1305/Seal-16 246kB/s ±35% 527kB/s ±13% +114.23% (p=0.000 n=10+10) Chacha20Poly1305/Open-64 927kB/s ±31% 1664kB/s ±22% +79.50% (p=0.000 n=10+10) Chacha20Poly1305/Seal-64 993kB/s ±10% 1709kB/s ± 8% +72.02% (p=0.000 n=9+8) Chacha20Poly1305/Open-256 1.70MB/s ±13% 2.90MB/s ±18% +70.88% (p=0.000 n=9+10) Chacha20Poly1305/Seal-256 1.74MB/s ±17% 2.81MB/s ±28% +61.16% (p=0.000 n=10+10) Chacha20Poly1305/Open-1024 2.26MB/s ±15% 3.99MB/s ±20% +76.38% (p=0.000 n=10+10) Chacha20Poly1305/Seal-1024 2.20MB/s ±13% 3.92MB/s ±32% +78.82% (p=0.000 n=10+10) Chacha20Poly1305/Open-8192 2.31MB/s ±19% 4.24MB/s ±14% +83.72% (p=0.000 n=10+10) Chacha20Poly1305/Seal-8192 2.30MB/s ±29% 4.09MB/s ±19% +77.66% (p=0.000 n=10+10) Chacha20Poly1305/Open-16384 2.34MB/s ±10% 3.93MB/s ±19% +68.04% (p=0.000 n=9+10) Chacha20Poly1305/Seal-16384 2.23MB/s ±17% 3.79MB/s ±23% +70.00% (p=0.000 n=10+10) Fixes golang#39139

gopherbot · 2021-03-15T15:56:26Z

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gopherbot · 2021-03-15T15:58:33Z

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