atomic.AddInt64() Function in Golang With Examples

In Go language, atomic packages supply lower-level atomic memory that is helpful is implementing synchronization algorithms. The AddInt64() function in Go language is used to automatically add delta to the *addr. This function is defined under the atomic package. Here, you need to import “sync/atomic” package in order to use these functions.

Syntax:

func AddInt64(addr *int64, delta int64) (new int64)

Here, addr indicates address and delta indicates a small number of bits greater than zero.

Note: (*int64) is the pointer to a int64 value. Moreover, int64 contains the set of all signed 64-bit integers from -9223372036854775808 to 9223372036854775807.

Return Value: It adds addr and delta automatically and returns a new value.

Example 1:

// Golang program to illustrate the usage of
// AddInt64 function

// Including main package
package main

// importing fmt and sync/atomic
import (
    "fmt"
    "sync/atomic"
)

// Main function
func main() {

    // Assigning values
    // to the int64
    var (
        s int64 = 67656
        t int64 = 90
        u int64 = 922337203685477580
        v int64 = -9223372036854775807
    )

    // Assigning constant
    // values to int64
    const (
        w int64 = 5
        x int64 = 8
    )

    // Calling AddInt64 method
    // with its parameters
    output_1 := atomic.AddInt64(&s, w)
    output_2 := atomic.AddInt64(&t, x-w)
    output_3 := atomic.AddInt64(&u, x-6)
    output_4 := atomic.AddInt64(&v, -x)

    // Displays the output after adding
    // addr and delta automatically
    fmt.Println(output_1)
    fmt.Println(output_2)
    fmt.Println(output_3)
    fmt.Println(output_4)
}

Output:

67661
93
922337203685477582
9223372036854775801

Example 2:

// Golang Program to illustrate the usage of
// AddInt64 function

// Including main package
package main

// importing fmt and sync/atomic
import (
    "fmt"
    "sync/atomic"
)

// Defining addr of type int64
type addr int64

// function that adds addr and delta
func (s *addr) adds() int64 {

    // Calling AddInt64() function
    // with its parameter
    return atomic.AddInt64((*int64)(s), 9)
}

// Main function
func main() {

    // Defining s
    var s addr

    // For loop to increment
    // the value of s
    for i := 1; i < 10000; i *= 5 {

        // Displays the new value
        // after adding delta and addr
        fmt.Println(s.adds())
    }
}

Output:

9
18
27
36
45
54

In the above example, we have defined a function adds that returns the output returned from calling AddInt64 method. In the main function, we have defined a “for” loop that will increment the value of ‘s’ in each call. Here, the second parameter of the AddInt64() method is constant and only the value of the first parameter is variable. However, the output of the previous call will be the value of the first parameter of the AddInt64() method in the next call until the loop stops.

Lets see how above example works:

1st parameter = 0, 2nd parameter = 9   // returns (0 + 9 = 9)

// Now, the above output is 1st parameter in next call to AddInt64() method
1st parameter = 9, 2nd parameter = 9   // returns (9 + 9 = 18)
1st parameter = 18, 2nd parameter = 9   // returns (18 + 9 = 27) and so on.