1package gates
 2
 3import (
 4	"fmt"
 5	"regexp"
 6	"strconv"
 7
 8	"github.com/consensys/gnark/frontend"
 9	gl "github.com/succinctlabs/gnark-plonky2-verifier/goldilocks"
10)
11
12var arithmeticExtensionGateRegex = regexp.MustCompile("ArithmeticExtensionGate { num_ops: (?P<numOps>[0-9]+) }")
13
14func deserializeExtensionArithmeticGate(parameters map[string]string) Gate {
15	// Has the format "ArithmeticExtensionGate { num_ops: 10 }"
16	numOps, hasNumOps := parameters["numOps"]
17	if !hasNumOps {
18		panic("Missing field num_ops in ArithmeticExtensionGate")
19	}
20
21	numOpsInt, err := strconv.Atoi(numOps)
22	if err != nil {
23		panic("Invalid num_ops field in ArithmeticExtensionGate")
24	}
25
26	return NewArithmeticExtensionGate(uint64(numOpsInt))
27}
28
29type ArithmeticExtensionGate struct {
30	numOps uint64
31}
32
33func NewArithmeticExtensionGate(numOps uint64) *ArithmeticExtensionGate {
34	return &ArithmeticExtensionGate{
35		numOps: numOps,
36	}
37}
38
39func (g *ArithmeticExtensionGate) Id() string {
40	return fmt.Sprintf("ArithmeticExtensionGate { num_ops: %d }", g.numOps)
41}
42
43func (g *ArithmeticExtensionGate) wiresIthMultiplicand0(i uint64) Range {
44	return Range{4 * gl.D * i, 4*gl.D*i + gl.D}
45}
46
47func (g *ArithmeticExtensionGate) wiresIthMultiplicand1(i uint64) Range {
48	return Range{4*gl.D*i + gl.D, 4*gl.D*i + 2*gl.D}
49}
50
51func (g *ArithmeticExtensionGate) wiresIthAddend(i uint64) Range {
52	return Range{4*gl.D*i + 2*gl.D, 4*gl.D*i + 3*gl.D}
53}
54
55func (g *ArithmeticExtensionGate) wiresIthOutput(i uint64) Range {
56	return Range{4*gl.D*i + 3*gl.D, 4*gl.D*i + 4*gl.D}
57}
58
59func (g *ArithmeticExtensionGate) EvalUnfiltered(
60	api frontend.API,
61	glApi *gl.Chip,
62	vars EvaluationVars,
63) []gl.QuadraticExtensionVariable {
64	const0 := vars.localConstants[0]
65	const1 := vars.localConstants[1]
66
67	constraints := []gl.QuadraticExtensionVariable{}
68	for i := uint64(0); i < g.numOps; i++ {
69		multiplicand0 := vars.GetLocalExtAlgebra(g.wiresIthMultiplicand0(i))
70		multiplicand1 := vars.GetLocalExtAlgebra(g.wiresIthMultiplicand1(i))
71		addend := vars.GetLocalExtAlgebra(g.wiresIthAddend(i))
72		output := vars.GetLocalExtAlgebra(g.wiresIthOutput(i))
73
74		mul := glApi.MulExtensionAlgebra(multiplicand0, multiplicand1)
75		scaled_mul := glApi.ScalarMulExtensionAlgebra(const0, mul)
76		computed_output := glApi.ScalarMulExtensionAlgebra(const1, addend)
77		computed_output = glApi.AddExtensionAlgebra(computed_output, scaled_mul)
78
79		diff := glApi.SubExtensionAlgebra(output, computed_output)
80		for j := 0; j < gl.D; j++ {
81			constraints = append(constraints, diff[j])
82		}
83	}
84
85	return constraints
86}