Merge pull request #496 from Consensys/sis/export-fft64

Chores: export the unrolled FFT64 out of SIS
Consensys · Apr 11, 2024 · f2e861f · f2e861f
2 parents 73d5980 + fe0c2ca
commit f2e861f
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Showing 7 changed files with 25 additions and 25 deletions.
diff --git a/ecc/bls12-377/fr/sis/sis.go b/ecc/bls12-377/fr/sis/sis.go
@@ -52,7 +52,7 @@ type RSis struct {
 
 	// domain for the polynomial multiplication
 	Domain        *fft.Domain
-	twiddleCosets []fr.Element // see fft64 and precomputeTwiddlesCoset
+	twiddleCosets []fr.Element // see FFT64 and precomputeTwiddlesCoset
 
 	// d, the degree of X^{d}+1
 	Degree int
@@ -129,7 +129,7 @@ func NewRSis(seed int64, logTwoDegree, logTwoBound, maxNbElementsToHash int) (*R
 	}
 	if r.LogTwoBound == 8 && r.Degree == 64 {
 		// TODO @gbotrel fixme, that's dirty.
-		r.twiddleCosets = precomputeTwiddlesCoset(r.Domain.Generator, r.Domain.FrMultiplicativeGen)
+		r.twiddleCosets = PrecomputeTwiddlesCoset(r.Domain.Generator, r.Domain.FrMultiplicativeGen)
 	}
 
 	// filling A
@@ -199,7 +199,7 @@ func (r *RSis) Sum(b []byte) []byte {
 		k := m[i*r.Degree : (i+1)*r.Degree]
 		if fastPath {
 			// fast path.
-			fft64(k, r.twiddleCosets)
+			FFT64(k, r.twiddleCosets)
 		} else {
 			r.Domain.FFT(k, fft.DIF, fft.OnCoset(), fft.WithNbTasks(1))
 		}

diff --git a/ecc/bls12-377/fr/sis/sis_fft.go b/ecc/bls12-377/fr/sis/sis_fft.go
diff --git a/ecc/bls12-377/fr/sis/sis_test.go b/ecc/bls12-377/fr/sis/sis_test.go
@@ -427,8 +427,8 @@ func TestUnrolledFFT(t *testing.T) {
 	domain.FFT(k1, fft.DIF, fft.OnCoset(), fft.WithNbTasks(1))
 
 	// unrolled FFT
-	twiddlesCoset := precomputeTwiddlesCoset(domain.Generator, domain.FrMultiplicativeGen)
-	fft64(k2, twiddlesCoset)
+	twiddlesCoset := PrecomputeTwiddlesCoset(domain.Generator, domain.FrMultiplicativeGen)
+	FFT64(k2, twiddlesCoset)
 
 	// compare results
 	for i := 0; i < size; i++ {

diff --git a/ecc/bn254/fr/sis/sis.go b/ecc/bn254/fr/sis/sis.go
@@ -52,7 +52,7 @@ type RSis struct {
 
 	// domain for the polynomial multiplication
 	Domain        *fft.Domain
-	twiddleCosets []fr.Element // see fft64 and precomputeTwiddlesCoset
+	twiddleCosets []fr.Element // see FFT64 and precomputeTwiddlesCoset
 
 	// d, the degree of X^{d}+1
 	Degree int
@@ -129,7 +129,7 @@ func NewRSis(seed int64, logTwoDegree, logTwoBound, maxNbElementsToHash int) (*R
 	}
 	if r.LogTwoBound == 8 && r.Degree == 64 {
 		// TODO @gbotrel fixme, that's dirty.
-		r.twiddleCosets = precomputeTwiddlesCoset(r.Domain.Generator, r.Domain.FrMultiplicativeGen)
+		r.twiddleCosets = PrecomputeTwiddlesCoset(r.Domain.Generator, r.Domain.FrMultiplicativeGen)
 	}
 
 	// filling A
@@ -199,7 +199,7 @@ func (r *RSis) Sum(b []byte) []byte {
 		k := m[i*r.Degree : (i+1)*r.Degree]
 		if fastPath {
 			// fast path.
-			fft64(k, r.twiddleCosets)
+			FFT64(k, r.twiddleCosets)
 		} else {
 			r.Domain.FFT(k, fft.DIF, fft.OnCoset(), fft.WithNbTasks(1))
 		}

diff --git a/ecc/bn254/fr/sis/sis_fft.go b/ecc/bn254/fr/sis/sis_fft.go
diff --git a/ecc/bn254/fr/sis/sis_test.go b/ecc/bn254/fr/sis/sis_test.go
@@ -426,8 +426,8 @@ func TestUnrolledFFT(t *testing.T) {
 	domain.FFT(k1, fft.DIF, fft.OnCoset(), fft.WithNbTasks(1))
 
 	// unrolled FFT
-	twiddlesCoset := precomputeTwiddlesCoset(domain.Generator, domain.FrMultiplicativeGen)
-	fft64(k2, twiddlesCoset)
+	twiddlesCoset := PrecomputeTwiddlesCoset(domain.Generator, domain.FrMultiplicativeGen)
+	FFT64(k2, twiddlesCoset)
 
 	// compare results
 	for i := 0; i < size; i++ {

diff --git a/internal/generator/sis/template/fft.go.tmpl b/internal/generator/sis/template/fft.go.tmpl
@@ -3,10 +3,10 @@ import (
 	"math/big"
 )
 
-// fft64 is generated by gnark-crypto and contains the unrolled code for FFT (DIF) on 64 elements
+// FFT64 is generated by gnark-crypto and contains the unrolled code for FFT (DIF) on 64 elements
 // equivalent code: r.Domain.FFT(k, fft.DIF, fft.OnCoset(), fft.WithNbTasks(1))
-// twiddlesCoset must be pre-computed from twiddles and coset table, see precomputeTwiddlesCoset
-func fft64(a []fr.Element,  twiddlesCoset []fr.Element) {
+// twiddlesCoset must be pre-computed from twiddles and coset table, see PrecomputeTwiddlesCoset
+func FFT64(a []fr.Element,  twiddlesCoset []fr.Element) {
 
 	{{- /* notes: 
 		this function can be updated with larger n
@@ -47,9 +47,9 @@ func fft64(a []fr.Element,  twiddlesCoset []fr.Element) {
 	{{- end}}
 }
 
-// precomputeTwiddlesCoset precomputes twiddlesCoset from twiddles and coset table
+// PrecomputeTwiddlesCoset precomputes twiddlesCoset from twiddles and coset table
 // it then return all elements in the correct order for the unrolled FFT.
-func precomputeTwiddlesCoset(generator, shifter fr.Element) []fr.Element {
+func PrecomputeTwiddlesCoset(generator, shifter fr.Element) []fr.Element {
 	toReturn := make([]fr.Element,  63)
 	var r, s fr.Element
 	e := new(big.Int)