Golang Int.AndNot方法代碼示例

// UnaryOp returns the result of the unary expression op y.
// The operation must be defined for the operand.
// If size >= 0 it specifies the ^ (xor) result size in bytes.
// If y is Unknown, the result is Unknown.
//
func UnaryOp(op token.Token, y Value, size int) Value {
	switch op {
	case token.ADD:
		switch y.(type) {
		case unknownVal, int64Val, intVal, floatVal, complexVal:
			return y
		}

	case token.SUB:
		switch y := y.(type) {
		case unknownVal:
			return y
		case int64Val:
			if z := -y; z != y {
				return z // no overflow
			}
			return normInt(new(big.Int).Neg(big.NewInt(int64(y))))
		case intVal:
			return normInt(new(big.Int).Neg(y.val))
		case floatVal:
			return normFloat(new(big.Rat).Neg(y.val))
		case complexVal:
			return normComplex(new(big.Rat).Neg(y.re), new(big.Rat).Neg(y.im))
		}

	case token.XOR:
		var z big.Int
		switch y := y.(type) {
		case unknownVal:
			return y
		case int64Val:
			z.Not(big.NewInt(int64(y)))
		case intVal:
			z.Not(y.val)
		default:
			goto Error
		}
		// For unsigned types, the result will be negative and
		// thus "too large": We must limit the result size to
		// the type's size.
		if size >= 0 {
			s := uint(size) * 8
			z.AndNot(&z, new(big.Int).Lsh(big.NewInt(-1), s)) // z &^= (-1)<<s
		}
		return normInt(&z)

	case token.NOT:
		switch y := y.(type) {
		case unknownVal:
			return y
		case boolVal:
			return !y
		}
	}

Error:
	panic(fmt.Sprintf("invalid unary operation %s%v", op, y))
}

// unaryOpConst returns the result of the constant evaluation op x where x is of the given type.
func unaryOpConst(x interface{}, op token.Token, typ *Basic) interface{} {
	switch op {
	case token.ADD:
		return x // nothing to do
	case token.SUB:
		switch x := x.(type) {
		case int64:
			if z := -x; z != x {
				return z // no overflow
			}
			// overflow - need to convert to big.Int
			return normalizeIntConst(new(big.Int).Neg(big.NewInt(x)))
		case *big.Int:
			return normalizeIntConst(new(big.Int).Neg(x))
		case *big.Rat:
			return normalizeRatConst(new(big.Rat).Neg(x))
		case complex:
			return newComplex(new(big.Rat).Neg(x.re), new(big.Rat).Neg(x.im))
		}
	case token.XOR:
		var z big.Int
		switch x := x.(type) {
		case int64:
			z.Not(big.NewInt(x))
		case *big.Int:
			z.Not(x)
		default:
			unreachable()
		}
		// For unsigned types, the result will be negative and
		// thus "too large": We must limit the result size to
		// the type's size.
		if typ.Info&IsUnsigned != 0 {
			s := uint(typ.Size) * 8
			if s == 0 {
				// platform-specific type
				// TODO(gri) this needs to be factored out
				switch typ.Kind {
				case Uint:
					s = intBits
				case Uintptr:
					s = ptrBits
				default:
					unreachable()
				}
			}
			// z &^= (-1)<<s
			z.AndNot(&z, new(big.Int).Lsh(big.NewInt(-1), s))
		}
		return normalizeIntConst(&z)
	case token.NOT:
		return !x.(bool)
	}
	unreachable()
	return nil
}

func binaryIntOp(x *big.Int, op token.Token, y *big.Int) interface{} {
	var z big.Int
	switch op {
	case token.ADD:
		return z.Add(x, y)
	case token.SUB:
		return z.Sub(x, y)
	case token.MUL:
		return z.Mul(x, y)
	case token.QUO:
		return z.Quo(x, y)
	case token.REM:
		return z.Rem(x, y)
	case token.AND:
		return z.And(x, y)
	case token.OR:
		return z.Or(x, y)
	case token.XOR:
		return z.Xor(x, y)
	case token.AND_NOT:
		return z.AndNot(x, y)
	case token.SHL:
		// The shift length must be uint, or untyped int and
		// convertible to uint.
		// TODO 32/64bit
		if y.BitLen() > 32 {
			panic("Excessive shift length")
		}
		return z.Lsh(x, uint(y.Int64()))
	case token.SHR:
		if y.BitLen() > 32 {
			panic("Excessive shift length")
		}
		return z.Rsh(x, uint(y.Int64()))
	case token.EQL:
		return x.Cmp(y) == 0
	case token.NEQ:
		return x.Cmp(y) != 0
	case token.LSS:
		return x.Cmp(y) < 0
	case token.LEQ:
		return x.Cmp(y) <= 0
	case token.GTR:
		return x.Cmp(y) > 0
	case token.GEQ:
		return x.Cmp(y) >= 0
	}
	panic("unreachable")
}

func bigIntAndNot(oldValues [][]byte, newValues [][]byte, w float64) (result [][]byte) {
	var sum *big.Int
	if oldValues != nil {
		sum = new(big.Int).SetBytes(oldValues[0])
		for _, b := range newValues {
			sum.AndNot(sum, new(big.Int).Mul(common.DecodeBigInt(b), big.NewInt(int64(w))))
		}
	} else {
		sum = new(big.Int).Mul(new(big.Int).SetBytes(newValues[0]), big.NewInt(int64(w)))
		for _, b := range newValues[1:] {
			sum.AndNot(sum, new(big.Int).Mul(common.DecodeBigInt(b), big.NewInt(int64(w))))
		}
	}
	return [][]byte{sum.Bytes()}
}

// unaryOpConst returns the result of the constant evaluation op x where x is of the given type.
func unaryOpConst(x interface{}, ctxt *Context, op token.Token, typ *Basic) interface{} {
	switch op {
	case token.ADD:
		return x // nothing to do
	case token.SUB:
		switch x := x.(type) {
		case int64:
			if z := -x; z != x {
				return z // no overflow
			}
			// overflow - need to convert to big.Int
			return normalizeIntConst(new(big.Int).Neg(big.NewInt(x)))
		case *big.Int:
			return normalizeIntConst(new(big.Int).Neg(x))
		case *big.Rat:
			return normalizeRatConst(new(big.Rat).Neg(x))
		case Complex:
			return newComplex(new(big.Rat).Neg(x.Re), new(big.Rat).Neg(x.Im))
		}
	case token.XOR:
		var z big.Int
		switch x := x.(type) {
		case int64:
			z.Not(big.NewInt(x))
		case *big.Int:
			z.Not(x)
		default:
			unreachable()
		}
		// For unsigned types, the result will be negative and
		// thus "too large": We must limit the result size to
		// the type's size.
		if typ.Info&IsUnsigned != 0 {
			s := uint(ctxt.sizeof(typ)) * 8
			z.AndNot(&z, new(big.Int).Lsh(big.NewInt(-1), s)) // z &^= (-1)<<s
		}
		return normalizeIntConst(&z)
	case token.NOT:
		return !x.(bool)
	}
	unreachable()
	return nil
}

func binaryIntOp(x *big.Int, op token.Token, y *big.Int) interface{} {
	var z big.Int
	switch op {
	case token.ADD:
		return z.Add(x, y)
	case token.SUB:
		return z.Sub(x, y)
	case token.MUL:
		return z.Mul(x, y)
	case token.QUO:
		return z.Quo(x, y)
	case token.REM:
		return z.Rem(x, y)
	case token.AND:
		return z.And(x, y)
	case token.OR:
		return z.Or(x, y)
	case token.XOR:
		return z.Xor(x, y)
	case token.AND_NOT:
		return z.AndNot(x, y)
	case token.SHL:
		panic("unimplemented")
	case token.SHR:
		panic("unimplemented")
	case token.EQL:
		return x.Cmp(y) == 0
	case token.NEQ:
		return x.Cmp(y) != 0
	case token.LSS:
		return x.Cmp(y) < 0
	case token.LEQ:
		return x.Cmp(y) <= 0
	case token.GTR:
		return x.Cmp(y) > 0
	case token.GEQ:
		return x.Cmp(y) >= 0
	}
	panic("unreachable")
}

// binaryOpConst returns the result of the constant evaluation x op y;
// both operands must be of the same "kind" (boolean, numeric, or string).
// If intDiv is true, division (op == token.QUO) is using integer division
// (and the result is guaranteed to be integer) rather than floating-point
// division. Division by zero leads to a run-time panic.
//
func binaryOpConst(x, y interface{}, op token.Token, intDiv bool) interface{} {
	x, y = matchConst(x, y)

	switch x := x.(type) {
	case bool:
		y := y.(bool)
		switch op {
		case token.LAND:
			return x && y
		case token.LOR:
			return x || y
		default:
			unreachable()
		}

	case int64:
		y := y.(int64)
		switch op {
		case token.ADD:
			// TODO(gri) can do better than this
			if is63bit(x) && is63bit(y) {
				return x + y
			}
			return normalizeIntConst(new(big.Int).Add(big.NewInt(x), big.NewInt(y)))
		case token.SUB:
			// TODO(gri) can do better than this
			if is63bit(x) && is63bit(y) {
				return x - y
			}
			return normalizeIntConst(new(big.Int).Sub(big.NewInt(x), big.NewInt(y)))
		case token.MUL:
			// TODO(gri) can do better than this
			if is32bit(x) && is32bit(y) {
				return x * y
			}
			return normalizeIntConst(new(big.Int).Mul(big.NewInt(x), big.NewInt(y)))
		case token.REM:
			return x % y
		case token.QUO:
			if intDiv {
				return x / y
			}
			return normalizeRatConst(new(big.Rat).SetFrac(big.NewInt(x), big.NewInt(y)))
		case token.AND:
			return x & y
		case token.OR:
			return x | y
		case token.XOR:
			return x ^ y
		case token.AND_NOT:
			return x &^ y
		default:
			unreachable()
		}

	case *big.Int:
		y := y.(*big.Int)
		var z big.Int
		switch op {
		case token.ADD:
			z.Add(x, y)
		case token.SUB:
			z.Sub(x, y)
		case token.MUL:
			z.Mul(x, y)
		case token.REM:
			z.Rem(x, y)
		case token.QUO:
			if intDiv {
				z.Quo(x, y)
			} else {
				return normalizeRatConst(new(big.Rat).SetFrac(x, y))
			}
		case token.AND:
			z.And(x, y)
		case token.OR:
			z.Or(x, y)
		case token.XOR:
			z.Xor(x, y)
		case token.AND_NOT:
			z.AndNot(x, y)
		default:
			unreachable()
		}
		return normalizeIntConst(&z)

	case *big.Rat:
		y := y.(*big.Rat)
		var z big.Rat
		switch op {
		case token.ADD:
			z.Add(x, y)
		case token.SUB:
			z.Sub(x, y)
//.........這裏部分代碼省略.........

// Post-order traversal, equivalent to postfix notation.
func Eval(node interface{}) (*big.Int, error) {
	switch nn := node.(type) {
	case *ast.BinaryExpr:
		z := new(big.Int)
		x, xerr := Eval(nn.X)
		if xerr != nil {
			return nil, xerr
		}
		y, yerr := Eval(nn.Y)
		if yerr != nil {
			return nil, yerr
		}
		switch nn.Op {
		case token.ADD:
			return z.Add(x, y), nil
		case token.SUB:
			return z.Sub(x, y), nil
		case token.MUL:
			return z.Mul(x, y), nil
		case token.QUO:
			if y.Sign() == 0 { // 0 denominator
				return nil, DivideByZero
			}
			return z.Quo(x, y), nil
		case token.REM:
			if y.Sign() == 0 {
				return nil, DivideByZero
			}
			return z.Rem(x, y), nil
		case token.AND:
			return z.And(x, y), nil
		case token.OR:
			return z.Or(x, y), nil
		case token.XOR:
			return z.Xor(x, y), nil
		case token.SHL:
			if y.Sign() < 0 { // negative shift
				return nil, NegativeShift
			}
			return z.Lsh(x, uint(y.Int64())), nil
		case token.SHR:
			if y.Sign() < 0 {
				return nil, NegativeShift
			}
			return z.Rsh(x, uint(y.Int64())), nil
		case token.AND_NOT:
			return z.AndNot(x, y), nil
		default:
			return nil, UnknownOpErr
		}
	case *ast.UnaryExpr:
		var z *big.Int
		var err error
		if z, err = Eval(nn.X); err != nil {
			return nil, err
		}
		switch nn.Op {
		case token.SUB: // -x
			return z.Neg(z), nil
		case token.XOR: // ^x
			return z.Not(z), nil
		case token.ADD: // +x (useless)
			return z, nil
		}
	case *ast.BasicLit:
		z := new(big.Int)
		switch nn.Kind {
		case token.INT:
			z.SetString(nn.Value, 0)
			return z, nil
		default:
			return nil, UnknownLitErr
		}
	case *ast.ParenExpr:
		z, err := Eval(nn.X)
		if err != nil {
			return nil, err
		}
		return z, nil
	case *ast.CallExpr:
		ident, ok := nn.Fun.(*ast.Ident)
		if !ok {
			return nil, UnknownTokenErr // quarter to four am; dunno correct error
		}
		var f Func
		f, ok = FuncMap[ident.Name]
		if !ok {
			return nil, UnknownFuncErr
		}
		var aerr error
		args := make([]*big.Int, len(nn.Args))
		for i, a := range nn.Args {
			if args[i], aerr = Eval(a); aerr != nil {
				return nil, aerr
			}
		}
		x, xerr := f(args...)
		if xerr != nil {
			return nil, xerr
//.........這裏部分代碼省略.........