1.2 KiB
Usage
At the root of your repo:
go get github.com/consensys/gnark-crypto/field
then in a main.go (that can be called using a go:generate workflow):
generator.GenerateFF(packageName, structName, modulus, destinationPath, false)
The generated type has an API that's similar with big.Int
Example API signature
// Mul z = x * y mod q
func (z *Element) Mul(x, y *Element) *Element
and can be used like so:
var a, b Element
a.SetUint64(2)
b.SetString("984896738")
a.Mul(a, b)
a.Sub(a, a)
.Add(a, b)
.Inv(a)
b.Exp(b, 42)
b.Neg(b)
Build tags
Generates optimized assembly for amd64 target.
For the Mul operation, using ADX instructions and ADOX/ADCX result in a significant performance gain.
The "default" target amd64 checks if the running architecture supports these instruction, and reverts to generic path if not. This check adds a branch and forces the function to reserve some bytes on the frame to store the argument to call _mulGeneric .
This package outputs code that can be compiled with amd64_adx flag which omits this check. Will crash if the platform running the binary doesn't support the ADX instructions (roughly, before 2016).