Javascript – does memory allocated if function returns early?

For efficient memory usage of a highly used class instance (multiple calls to init), I would like to know if memory for anything inside init function is allocated if it returns early.

Sandbox

class X {
    private static smth: Smth

    public static init(): Smth {
        // if this is evalueated to true and returned
        if (this.smth) {
            return this.smth;
        }

        // does memory allocated here (imagine there will be a big object)?
        const smth: Smth = {
            x: 1
        }

        this.smth = smth

        return this.smth
    }

    // if for previous question answer is yes, can we avoid memory allocation for `const smth` like this?
    public static getInstance(): Smth {
        if (!this.smth) {
            throw new Error("Not initialized");
        }

        return this.init();
    }
}

type Smth = {
    x: number
}