Implement ModBuiltin (#666)

* implement partial functionalities and structs required * run fmt * Introduce max func * Added more functions * ran fmt * Add test for modulo * Added structure for integrating builtin with the vm * Added useful comments * Update FillMemory * Added more comments * Add test * Added TODOs * fixes * update loop * Added addmod and mulmod * added some fixes * test passes now * fix error and test * Make tests pass * mod subtraction tests * Added some comments * Added subtraction tests * Added recursive case as well * nit * Add multiplication test * refactor math utils * move one math utils function * All Tests pass * nit * Added mirror functionality * remove redundant test * updated checkwrite and infervalue * nit
NethermindEth · Sep 27, 2024 · f1f925d · f1f925d
1 parent 9afede6
commit f1f925d
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Showing 12 changed files with 884 additions and 134 deletions.
diff --git a/pkg/hintrunner/core/hint.go b/pkg/hintrunner/core/hint.go
@@ -540,7 +540,7 @@ func (hint U256InvModN) Execute(vm *VM.VirtualMachine, _ *hinter.HintRunnerConte
 	n := new(big.Int).Lsh(&N1BigInt, 128)
 	n.Add(n, &N0BigInt)
 
-	_, r, g := u.Igcdex(n, b)
+	_, r, g := utils.Igcdex(n, b)
 	mask := new(big.Int).Lsh(big.NewInt(1), 128)
 	mask.Sub(mask, big.NewInt(1))
 

diff --git a/pkg/hintrunner/utils/math_utils.go b/pkg/hintrunner/utils/math_utils.go
@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"math/big"
 
+	"github.com/NethermindEth/cairo-vm-go/pkg/utils"
 	"github.com/consensys/gnark-crypto/ecc/stark-curve/fp"
 )
 
@@ -55,7 +56,7 @@ func AsIntBig(value *big.Int) big.Int {
 func Divmod(n, m, p *big.Int) (big.Int, error) {
 	// https://github.com/starkware-libs/cairo-lang/blob/efa9648f57568aad8f8a13fbf027d2de7c63c2c0/src/starkware/python/math_utils.py#L26
 
-	a, _, c := Igcdex(m, p)
+	a, _, c := utils.Igcdex(m, p)
 	if c.Cmp(big.NewInt(1)) != 0 {
 		return *big.NewInt(0), errors.New("no solution exists (gcd(m, p) != 1)")
 	}
@@ -65,68 +66,6 @@ func Divmod(n, m, p *big.Int) (big.Int, error) {
 	return *res, nil
 }
 
-func Igcdex(a, b *big.Int) (big.Int, big.Int, big.Int) {
-	// https://github.com/sympy/sympy/blob/d91b8ad6d36a59a879cc70e5f4b379da5fdd46ce/sympy/core/intfunc.py#L362
-
-	if a.Cmp(big.NewInt(0)) == 0 && b.Cmp(big.NewInt(0)) == 0 {
-		return *big.NewInt(0), *big.NewInt(1), *big.NewInt(0)
-	}
-	g, x, y := gcdext(a, b)
-	return x, y, g
-}
-
-func gcdext(a, b *big.Int) (big.Int, big.Int, big.Int) {
-	// https://github.com/sympy/sympy/blob/d91b8ad6d36a59a879cc70e5f4b379da5fdd46ce/sympy/external/ntheory.py#L125
-
-	if a.Cmp(big.NewInt(0)) == 0 || b.Cmp(big.NewInt(0)) == 0 {
-		g := new(big.Int)
-		if a.Cmp(big.NewInt(0)) == 0 {
-			g.Abs(b)
-		} else {
-			g.Abs(a)
-		}
-
-		if g.Cmp(big.NewInt(0)) == 0 {
-			return *big.NewInt(0), *big.NewInt(0), *big.NewInt(0)
-		}
-		return *g, *new(big.Int).Div(a, g), *new(big.Int).Div(b, g)
-	}
-
-	xSign, aSigned := sign(a)
-	ySign, bSigned := sign(b)
-	x, r := big.NewInt(1), big.NewInt(0)
-	y, s := big.NewInt(0), big.NewInt(1)
-
-	for bSigned.Sign() != 0 {
-		q, c := new(big.Int).DivMod(&aSigned, &bSigned, new(big.Int))
-		aSigned = bSigned
-		bSigned = *c
-		x, r = r, new(big.Int).Sub(x, new(big.Int).Mul(q, r))
-		y, s = s, new(big.Int).Sub(y, new(big.Int).Mul(q, s))
-	}
-
-	return aSigned, *new(big.Int).Mul(x, big.NewInt(int64(xSign))), *new(big.Int).Mul(y, big.NewInt(int64(ySign)))
-}
-
-func sign(n *big.Int) (int, big.Int) {
-	// https://github.com/sympy/sympy/blob/d91b8ad6d36a59a879cc70e5f4b379da5fdd46ce/sympy/external/ntheory.py#L119
-
-	if n.Sign() < 0 {
-		return -1, *new(big.Int).Abs(n)
-	}
-	return 1, *new(big.Int).Set(n)
-}
-
-func SafeDiv(x, y *big.Int) (big.Int, error) {
-	if y.Cmp(big.NewInt(0)) == 0 {
-		return *big.NewInt(0), fmt.Errorf("division by zero")
-	}
-	if new(big.Int).Mod(x, y).Cmp(big.NewInt(0)) != 0 {
-		return *big.NewInt(0), fmt.Errorf("%v is not divisible by %v", x, y)
-	}
-	return *new(big.Int).Div(x, y), nil
-}
-
 func IsQuadResidue(x *fp.Element) bool {
 	// Implementation adapted from sympy implementation which can be found here :
 	// https://github.com/sympy/sympy/blob/d91b8ad6d36a59a879cc70e5f4b379da5fdd46ce/sympy/ntheory/residue_ntheory.py#L689

diff --git a/pkg/hintrunner/utils/math_utils_test.go b/pkg/hintrunner/utils/math_utils_test.go
@@ -46,69 +46,3 @@ func TestDivMod(t *testing.T) {
 		})
 	}
 }
-
-func TestIgcdex(t *testing.T) {
-	// https://github.com/sympy/sympy/blob/e7fb2714f17b30b83e424448aad0da9e94a4b577/sympy/core/tests/test_numbers.py#L278
-	tests := []struct {
-		name                            string
-		a, b                            *big.Int
-		expectedX, expectedY, expectedG *big.Int
-	}{
-		{
-			name:      "Case 1",
-			a:         big.NewInt(2),
-			b:         big.NewInt(3),
-			expectedX: big.NewInt(-1),
-			expectedY: big.NewInt(1),
-			expectedG: big.NewInt(1),
-		},
-		{
-			name:      "Case 2",
-			a:         big.NewInt(10),
-			b:         big.NewInt(12),
-			expectedX: big.NewInt(-1),
-			expectedY: big.NewInt(1),
-			expectedG: big.NewInt(2),
-		},
-		{
-			name:      "Case 3",
-			a:         big.NewInt(100),
-			b:         big.NewInt(2004),
-			expectedX: big.NewInt(-20),
-			expectedY: big.NewInt(1),
-			expectedG: big.NewInt(4),
-		},
-		{
-			name:      "Case 4",
-			a:         big.NewInt(0),
-			b:         big.NewInt(0),
-			expectedX: big.NewInt(0),
-			expectedY: big.NewInt(1),
-			expectedG: big.NewInt(0),
-		},
-		{
-			name:      "Case 5",
-			a:         big.NewInt(1),
-			b:         big.NewInt(0),
-			expectedX: big.NewInt(1),
-			expectedY: big.NewInt(0),
-			expectedG: big.NewInt(1),
-		},
-	}
-
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			actualX, actualY, actualG := Igcdex(tt.a, tt.b)
-
-			if actualX.Cmp(tt.expectedX) != 0 {
-				t.Errorf("got x: %v, want: %v", actualX, tt.expectedX)
-			}
-			if actualY.Cmp(tt.expectedY) != 0 {
-				t.Errorf("got x: %v, want: %v", actualY, tt.expectedY)
-			}
-			if actualG.Cmp(tt.expectedG) != 0 {
-				t.Errorf("got x: %v, want: %v", actualG, tt.expectedG)
-			}
-		})
-	}
-}
diff --git a/pkg/hintrunner/zero/zerohint_ec.go b/pkg/hintrunner/zero/zerohint_ec.go
@@ -257,7 +257,7 @@ func newDivModNSafeDivPlusOneHint() hinter.Hinter {
 			valueBig.Mul(resBig, bBig)
 			valueBig.Sub(valueBig, aBig)
 
-			newValueBig, err := secp_utils.SafeDiv(valueBig, nBig)
+			newValueBig, err := utils.SafeDiv(valueBig, nBig)
 			if err != nil {
 				return err
 			}

diff --git a/pkg/hintrunner/zero/zerohint_signature.go b/pkg/hintrunner/zero/zerohint_signature.go
@@ -6,6 +6,7 @@ import (
 
 	"github.com/NethermindEth/cairo-vm-go/pkg/hintrunner/hinter"
 	secp_utils "github.com/NethermindEth/cairo-vm-go/pkg/hintrunner/utils"
+	"github.com/NethermindEth/cairo-vm-go/pkg/utils"
 	VM "github.com/NethermindEth/cairo-vm-go/pkg/vm"
 	"github.com/NethermindEth/cairo-vm-go/pkg/vm/builtins"
 	mem "github.com/NethermindEth/cairo-vm-go/pkg/vm/memory"
@@ -372,7 +373,7 @@ func newDivModSafeDivHint() hinter.Hinter {
 			}
 
 			divisor := new(big.Int).Sub(new(big.Int).Mul(res, b), a)
-			value, err := secp_utils.SafeDiv(divisor, N)
+			value, err := utils.SafeDiv(divisor, N)
 			if err != nil {
 				return err
 			}

diff --git a/pkg/runner/runner_test.go b/pkg/runner/runner_test.go
@@ -410,6 +410,28 @@ func TestEcOpBuiltin(t *testing.T) {
 	require.NoError(t, err)
 }
 
+func TestModuloBuiltin(t *testing.T) {
+	// modulo is located at fp - 3
+	// we first write 2048 and 5 to modulo
+	// then we read the modulo result from add and mul
+	// runner := createRunner(`
+	// 	[ap] = 2048;
+	// 	[ap] = [[fp - 3]];
+
+	// 	[ap + 1] = 5;
+	// 	[ap + 1] = [[fp - 3] + 1];
+	// 	ret;
+	// `, "small", sn.AddMod, sn.MulMod)
+
+	// err := runner.Run()
+	// require.NoError(t, err)
+
+	// modulo, ok := runner.vm.Memory.FindSegmentWithBuiltin("add_mod")
+	// require.True(t, ok)
+
+	// requireEqualSegments(t, createSegment(2048, 5), modulo)
+}
+
 func createRunner(code string, layoutName string, builtins ...builtins.BuiltinType) ZeroRunner {
 	program := createProgramWithBuiltins(code, builtins...)
 

diff --git a/pkg/utils/math.go b/pkg/utils/math.go
@@ -1,6 +1,8 @@
 package utils
 
 import (
+	"errors"
+	"fmt"
 	"math"
 	"math/big"
 	"math/bits"
@@ -156,3 +158,75 @@ func Int16FromBigInt(n *big.Int) (int16, bool) {
 func RightRot(value uint32, n uint32) uint32 {
 	return (value >> n) | ((value & ((1 << n) - 1)) << (32 - n))
 }
+
+func SafeDivUint64(x, y uint64) (uint64, error) {
+	if y == 0 {
+		return 0, fmt.Errorf("cannot divide: y division is zero")
+	}
+	if x%y != 0 {
+		return 0, errors.New("cannot divide: x is not divisible by y")
+	}
+	return x / y, nil
+}
+
+func Igcdex(a, b *big.Int) (big.Int, big.Int, big.Int) {
+	// https://github.com/sympy/sympy/blob/d91b8ad6d36a59a879cc70e5f4b379da5fdd46ce/sympy/core/intfunc.py#L362
+
+	if a.Cmp(big.NewInt(0)) == 0 && b.Cmp(big.NewInt(0)) == 0 {
+		return *big.NewInt(0), *big.NewInt(1), *big.NewInt(0)
+	}
+	g, x, y := gcdext(a, b)
+	return x, y, g
+}
+
+func gcdext(a, b *big.Int) (big.Int, big.Int, big.Int) {
+	// https://github.com/sympy/sympy/blob/d91b8ad6d36a59a879cc70e5f4b379da5fdd46ce/sympy/external/ntheory.py#L125
+
+	if a.Cmp(big.NewInt(0)) == 0 || b.Cmp(big.NewInt(0)) == 0 {
+		g := new(big.Int)
+		if a.Cmp(big.NewInt(0)) == 0 {
+			g.Abs(b)
+		} else {
+			g.Abs(a)
+		}
+
+		if g.Cmp(big.NewInt(0)) == 0 {
+			return *big.NewInt(0), *big.NewInt(0), *big.NewInt(0)
+		}
+		return *g, *new(big.Int).Div(a, g), *new(big.Int).Div(b, g)
+	}
+
+	xSign, aSigned := sign(a)
+	ySign, bSigned := sign(b)
+	x, r := big.NewInt(1), big.NewInt(0)
+	y, s := big.NewInt(0), big.NewInt(1)
+
+	for bSigned.Sign() != 0 {
+		q, c := new(big.Int).DivMod(&aSigned, &bSigned, new(big.Int))
+		aSigned = bSigned
+		bSigned = *c
+		x, r = r, new(big.Int).Sub(x, new(big.Int).Mul(q, r))
+		y, s = s, new(big.Int).Sub(y, new(big.Int).Mul(q, s))
+	}
+
+	return aSigned, *new(big.Int).Mul(x, big.NewInt(int64(xSign))), *new(big.Int).Mul(y, big.NewInt(int64(ySign)))
+}
+
+func sign(n *big.Int) (int, big.Int) {
+	// https://github.com/sympy/sympy/blob/d91b8ad6d36a59a879cc70e5f4b379da5fdd46ce/sympy/external/ntheory.py#L119
+
+	if n.Sign() < 0 {
+		return -1, *new(big.Int).Abs(n)
+	}
+	return 1, *new(big.Int).Set(n)
+}
+
+func SafeDiv(x, y *big.Int) (big.Int, error) {
+	if y.Cmp(big.NewInt(0)) == 0 {
+		return *big.NewInt(0), fmt.Errorf("division by zero")
+	}
+	if new(big.Int).Mod(x, y).Cmp(big.NewInt(0)) != 0 {
+		return *big.NewInt(0), fmt.Errorf("%v is not divisible by %v", x, y)
+	}
+	return *new(big.Int).Div(x, y), nil
+}
diff --git a/pkg/utils/math_test.go b/pkg/utils/math_test.go
@@ -1,6 +1,7 @@
 package utils
 
 import (
+	"math/big"
 	"testing"
 
 	"github.com/consensys/gnark-crypto/ecc/stark-curve/fp"
@@ -119,3 +120,69 @@ func TestRightRot(t *testing.T) {
 		})
 	}
 }
+
+func TestIgcdex(t *testing.T) {
+	// https://github.com/sympy/sympy/blob/e7fb2714f17b30b83e424448aad0da9e94a4b577/sympy/core/tests/test_numbers.py#L278
+	tests := []struct {
+		name                            string
+		a, b                            *big.Int
+		expectedX, expectedY, expectedG *big.Int
+	}{
+		{
+			name:      "Case 1",
+			a:         big.NewInt(2),
+			b:         big.NewInt(3),
+			expectedX: big.NewInt(-1),
+			expectedY: big.NewInt(1),
+			expectedG: big.NewInt(1),
+		},
+		{
+			name:      "Case 2",
+			a:         big.NewInt(10),
+			b:         big.NewInt(12),
+			expectedX: big.NewInt(-1),
+			expectedY: big.NewInt(1),
+			expectedG: big.NewInt(2),
+		},
+		{
+			name:      "Case 3",
+			a:         big.NewInt(100),
+			b:         big.NewInt(2004),
+			expectedX: big.NewInt(-20),
+			expectedY: big.NewInt(1),
+			expectedG: big.NewInt(4),
+		},
+		{
+			name:      "Case 4",
+			a:         big.NewInt(0),
+			b:         big.NewInt(0),
+			expectedX: big.NewInt(0),
+			expectedY: big.NewInt(1),
+			expectedG: big.NewInt(0),
+		},
+		{
+			name:      "Case 5",
+			a:         big.NewInt(1),
+			b:         big.NewInt(0),
+			expectedX: big.NewInt(1),
+			expectedY: big.NewInt(0),
+			expectedG: big.NewInt(1),
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			actualX, actualY, actualG := Igcdex(tt.a, tt.b)
+
+			if actualX.Cmp(tt.expectedX) != 0 {
+				t.Errorf("got x: %v, want: %v", actualX, tt.expectedX)
+			}
+			if actualY.Cmp(tt.expectedY) != 0 {
+				t.Errorf("got x: %v, want: %v", actualY, tt.expectedY)
+			}
+			if actualG.Cmp(tt.expectedG) != 0 {
+				t.Errorf("got x: %v, want: %v", actualG, tt.expectedG)
+			}
+		})
+	}
+}