1package plonky2_verifier
 2
 3import (
 4	"fmt"
 5	. "gnark-plonky2-verifier/field"
 6	"strconv"
 7	"strings"
 8)
 9
10type gate interface {
11	Id() string
12	EvalUnfiltered(p *PlonkChip, vars EvaluationVars) []QuadraticExtension
13}
14
15func GateInstanceFromId(gateId string) gate {
16	if strings.HasPrefix(gateId, "ArithmeticGate") {
17		numOpsRaw := strings.Split(gateId, ":")[1]
18		numOpsRaw = strings.Split(numOpsRaw, "}")[0]
19		numOpsRaw = strings.TrimSpace(numOpsRaw)
20		numOps, err := strconv.Atoi(numOpsRaw)
21		if err != nil {
22			panic("Invalid gate ID for ArithmeticGate")
23		}
24		return NewArithmeticGate(uint64(numOps))
25	}
26
27	if strings.HasPrefix(gateId, "ConstantGate") {
28		numConstsRaw := strings.Split(gateId, ":")[1]
29		numConstsRaw = strings.Split(numConstsRaw, "}")[0]
30		numConstsRaw = strings.TrimSpace(numConstsRaw)
31		numConsts, err := strconv.Atoi(numConstsRaw)
32		if err != nil {
33			panic("Invalid gate ID")
34		}
35		return NewConstantGate(uint64(numConsts))
36	}
37
38	if gateId == "NoopGate" {
39		return NewNoopGate()
40	}
41
42	if gateId == "PublicInputGate" {
43		return NewPublicInputGate()
44	}
45
46	if strings.HasPrefix(gateId, "PoseidonGate") {
47		return NewPoseidonGate()
48	}
49
50	panic(fmt.Sprintf("Unknown gate ID %s", gateId))
51}
52
53func (p *PlonkChip) computeFilter(
54	row uint64,
55	groupRange Range,
56	s QuadraticExtension,
57	manySelector bool,
58) QuadraticExtension {
59	product := p.qeAPI.ONE_QE
60	for i := groupRange.start; i < groupRange.end; i++ {
61		if i == uint64(row) {
62			continue
63		}
64
65		product = p.qeAPI.MulExtension(product, p.qeAPI.SubExtension(s, p.qeAPI.FieldToQE(NewFieldElement(i))))
66	}
67
68	if manySelector {
69		product = p.qeAPI.MulExtension(product, p.qeAPI.SubExtension(s, p.qeAPI.FieldToQE(NewFieldElement(UNUSED_SELECTOR))))
70	}
71
72	return product
73}
74
75func (p *PlonkChip) evalFiltered(
76	g gate,
77	vars EvaluationVars,
78	row uint64,
79	selectorIndex uint64,
80	groupRange Range,
81	numSelectors uint64,
82) []QuadraticExtension {
83	filter := p.computeFilter(row, groupRange, vars.localConstants[selectorIndex], numSelectors > 1)
84
85	vars.RemovePrefix(numSelectors)
86
87	unfiltered := g.EvalUnfiltered(p, vars)
88	for i := range unfiltered {
89		unfiltered[i] = p.qeAPI.MulExtension(unfiltered[i], filter)
90	}
91	return unfiltered
92}