All Tests pass

pkg/vm/builtins/modulo.go

@@ -412,13 +412,24 @@ func (m *ModBuiltin) fillValue(mem *memory.Memory, inputs ModBuiltinInputs, inde
  }
  } else {
  x, _, gcd := utils.Igcdex(b, &inputs.p)
+ // if gcd != 1, the known value is 0, in which case the res must be 0
  if gcd.Cmp(big.NewInt(1)) != 0 {
  value = *new(big.Int).Div(&inputs.p, &gcd)
  } else {
  value = *new(big.Int).Mul(c, &x)
  value = *value.Mod(&value, &inputs.p)
+ tmpK, err := utils.SafeDiv(new(big.Int).Sub(new(big.Int).Mul(b, &value), c), &inputs.p)
+ if err != nil {
+ return false, err
+ }
+ if tmpK.Cmp(kBound) >= 0 {
+ return false, fmt.Errorf("%s builtin: ((%d * q) - %d) / %d > %d for any q > 0, such that %d * q = %d (mod %d) ", m.String(), b, c, &inputs.p, kBound, b, c, &inputs.p)
+ }
+ if tmpK.Cmp(big.NewInt(0)) < 0 {
+ // tmp_val + p * ((known - 1 - tmp_k) // known)
+ value = *value.Add(&value, new(big.Int).Mul(&inputs.p, new(big.Int).Div(new(big.Int).Sub(b, new(big.Int).Sub(&tmpK, big.NewInt(1))), b)))
+ }
  }
- value = *new(big.Int).Div(c, b)
  }
  if err := m.writeNWordsValue(mem, addresses[0], value); err != nil {
  return false, err

pkg/vm/builtins/modulo_test.go

@@ -43,7 +43,6 @@ func TestModuloBuiltin(t *testing.T) {
  // TODO: Once Checkwrite and InferValue are implemented, uncomment this
  // k, err := segment.Read(9)
  // require.NoError(t, err)
- // fmt.Println(k)
  // ans, err := k.FieldElement()
  // require.NoError(t, err)
  // expected := fp.NewElement(0)
@@ -185,7 +184,16 @@ func TestMulModBuiltinRunnerDivision(t *testing.T) {
  res1, err := checkResult(*runner, true, *big.NewInt(67), *big.NewInt(36), *big.NewInt(9))
  require.NoError(t, err)
  require.Equal(t, big.NewInt(4), res1)
- // res2, err := checkResult(*runner, true, *big.NewInt(67), *big.NewInt(138), *big.NewInt(41))
- // require.NoError(t, err)
- // require.Equal(t, big.NewInt(5), res2)
+ res2, err := checkResult(*runner, true, *big.NewInt(67), *big.NewInt(138), *big.NewInt(41))
+ require.NoError(t, err)
+ require.Equal(t, big.NewInt(5), res2)
+ res3, err := checkResult(*runner, true, *big.NewInt(67), *big.NewInt(272), *big.NewInt(41))
+ require.NoError(t, err)
+ require.Equal(t, big.NewInt(72), res3)
+ res4, err := checkResult(*runner, true, *big.NewInt(67), *big.NewInt(0), *big.NewInt(0))
+ require.NoError(t, err)
+ require.Equal(t, big.NewInt(1), res4)
+ res5, err := checkResult(*runner, true, *big.NewInt(66), *big.NewInt(6), *big.NewInt(3))
+ require.NoError(t, err)
+ require.Equal(t, big.NewInt(22), res5)
 }

pkg/vm/memory/memory.go

@@ -244,7 +244,6 @@ func (memory *Memory) Write(segmentIndex uint64, offset uint64, value *MemoryVal
  return fmt.Errorf("segment %d: unallocated", segmentIndex)
  }
  if err := memory.Segments[segmentIndex].Write(offset, value); err != nil {
- fmt.Println("error in write")
  return fmt.Errorf("segment %d, offset %d: %w", segmentIndex, offset, err)
  }
  return nil
@@ -264,7 +263,6 @@ func (memory *Memory) Read(segmentIndex uint64, offset uint64) (MemoryValue, err
  }
  mv, err := memory.Segments[segmentIndex].Read(offset)
  if err != nil {
- fmt.Println(err)
  return MemoryValue{}, fmt.Errorf("segment %d, offset %d: %w", segmentIndex, offset, err)
  }
  return mv, nil