This is a SM2 sm2p256v1 implementation whose performance is similar like golang native NIST P256 under amd64 .

SM2 encryption Benchmark

P-256/SM2(No tuning)
goos: windows
goarch: amd64
pkg: gmsm/sm2
BenchmarkLessThan32-6   	     210	   5665861 ns/op	   0.01 MB/s	 2601864 B/op	   27725 allocs/op
PASS
ok  	gmsm/sm2	5.629s

P-256/SM2(with P256/SM2 curve pure golang implementation)
goos: windows
goarch: amd64
pkg: gmsm/sm2
BenchmarkLessThan32_P256SM2-6   	    1027	   1169516 ns/op	    3874 B/op	      74 allocs/op
PASS
ok  	gmsm/sm2	1.564s

P-256/SM2(with P256/SM2 amd64 curve implementation, i think there are still improvement space for p256Sqr function)
goos: windows
goarch: amd64
pkg: github.com/emmansun/gmsm/sm2
BenchmarkLessThan32_P256SM2-6   	   10447	    115618 ns/op	    2357 B/op	      46 allocs/op
PASS
ok  	github.com/emmansun/gmsm/sm2	2.199s

P-256 (SM2 based on NIST P-256 curve)
goos: windows
goarch: amd64
pkg: gmsm/sm2
BenchmarkMoreThan32-6   	   13656	     86252 ns/op	    3141 B/op	      50 allocs/op
PASS
ok  	gmsm/sm2	4.139s