1package plonky2_verifier
 2
 3import (
 4	"fmt"
 5	. "gnark-ed25519/field"
 6	"math/bits"
 7
 8	"github.com/consensys/gnark/frontend"
 9)
10
11func reduceWithPowers(qe *QuadraticExtensionAPI, terms []QuadraticExtension, scalar QuadraticExtension) QuadraticExtension {
12	sum := qe.ZERO_QE
13
14	for i := len(terms) - 1; i >= 0; i-- {
15		sum = qe.AddExtension(
16			qe.MulExtension(
17				sum,
18				scalar,
19			),
20			terms[i],
21		)
22	}
23
24	return sum
25}
26
27// Computes `log_2(n)`, panicking if `n` is not a power of two.
28func log2Strict(n uint) int {
29	res := bits.TrailingZeros(n)
30	if n>>res != 1 {
31		panic(fmt.Sprintf("Not a power of two: %d", n))
32	}
33	return res
34}
35
36func SelectHash(fieldAPI frontend.API, bit frontend.Variable, leftHash, rightHash Hash) Hash {
37	var returnHash Hash
38	for i := 0; i < 4; i++ {
39		returnHash[i] = fieldAPI.Select(bit, leftHash[i], rightHash[i]).(F)
40	}
41
42	return returnHash
43}