PostDominator Class — react Architecture

Source Code

compiler/packages/babel-plugin-react-compiler/src/HIR/Dominator.ts lines 108–145

export class PostDominator<T> {
  #exit: T;
  #nodes: Map<T, T>;

  constructor(exit: T, nodes: Map<T, T>) {
    this.#exit = exit;
    this.#nodes = nodes;
  }

  // Returns the node representing normal exit from the function, ie return terminals.
  get exit(): T {
    return this.#exit;
  }

  /*
   * Returns the immediate dominator of the block with @param id if present. Returns null
   * if there is no immediate dominator (ie if the dominator is @param id itself).
   */
  get(id: T): T | null {
    const dominator = this.#nodes.get(id);
    CompilerError.invariant(dominator !== undefined, {
      reason: 'Unknown node',
      loc: GeneratedSource,
    });
    return dominator === id ? null : dominator;
  }

  debug(): string {
    const postDominators = new Map();
    for (const [key, value] of this.#nodes) {
      postDominators.set(`bb${key}`, `bb${value}`);
    }
    return prettyFormat({
      exit: `bb${this.exit}`,
      postDominators,
    });
  }
}