Fix/incorrect polynomial evaluation (#539)

* fix: fixed point shifting bn254 * feat: code gen * fix: moved err outside of the if scope
Consensys · Sep 25, 2024 · 11d2ed4 · 11d2ed4
1 parent 703a260
commit 11d2ed4
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Showing 8 changed files with 48 additions and 40 deletions.
diff --git a/ecc/bls12-377/fr/iop/polynomial.go b/ecc/bls12-377/fr/iop/polynomial.go
diff --git a/ecc/bls12-381/fr/iop/polynomial.go b/ecc/bls12-381/fr/iop/polynomial.go
diff --git a/ecc/bls24-315/fr/iop/polynomial.go b/ecc/bls24-315/fr/iop/polynomial.go
diff --git a/ecc/bls24-317/fr/iop/polynomial.go b/ecc/bls24-317/fr/iop/polynomial.go
diff --git a/ecc/bn254/fr/iop/polynomial.go b/ecc/bn254/fr/iop/polynomial.go
diff --git a/ecc/bw6-633/fr/iop/polynomial.go b/ecc/bw6-633/fr/iop/polynomial.go
diff --git a/ecc/bw6-761/fr/iop/polynomial.go b/ecc/bw6-761/fr/iop/polynomial.go
diff --git a/internal/generator/iop/template/polynomial.go.tmpl b/internal/generator/iop/template/polynomial.go.tmpl
@@ -152,19 +152,20 @@ func (p *Polynomial) Evaluate(x fr.Element) fr.Element {
 	}
 
 	var g fr.Element
+	gen, err := fft.Generator(uint64(p.size))
+	if err != nil {
+		panic(err)
+	}
 	if p.shift <= 5 {
-		gen, err := fft.Generator(uint64(p.size))
-		if err != nil {
-			panic(err)
-		}
 		g = smallExp(gen, p.shift)
 		x.Mul(&x, &g)
 		return p.polynomial.evaluate(x)
 	}
 
 	bs := big.NewInt(int64(p.shift))
-	g = *g.Exp(g, bs)
+	g = *g.Exp(gen, bs)
 	x.Mul(&x, &g)
+
 	return p.polynomial.evaluate(x)
 }