/*
|
MIT License http://www.opensource.org/licenses/mit-license.php
|
Author Tobias Koppers @sokra
|
*/
|
|
"use strict";
|
|
const { compareIds } = require("../util/comparators");
|
|
/** @typedef {import("../Chunk")} Chunk */
|
/** @typedef {import("../Chunk").ChunkId} ChunkId */
|
/** @typedef {import("../Compiler")} Compiler */
|
/** @typedef {import("../Module")} Module */
|
|
const PLUGIN_NAME = "FlagIncludedChunksPlugin";
|
|
class FlagIncludedChunksPlugin {
|
/**
|
* Applies the plugin by registering its hooks on the compiler.
|
* @param {Compiler} compiler the compiler instance
|
* @returns {void}
|
*/
|
apply(compiler) {
|
compiler.hooks.compilation.tap(PLUGIN_NAME, (compilation) => {
|
compilation.hooks.optimizeChunkIds.tap(PLUGIN_NAME, (chunks) => {
|
const chunkGraph = compilation.chunkGraph;
|
|
// prepare two bit integers for each module
|
// 2^31 is the max number represented as SMI in v8
|
// we want the bits distributed this way:
|
// the bit 2^31 is pretty rar and only one module should get it
|
// so it has a probability of 1 / modulesCount
|
// the first bit (2^0) is the easiest and every module could get it
|
// if it doesn't get a better bit
|
// from bit 2^n to 2^(n+1) there is a probability of p
|
// so 1 / modulesCount == p^31
|
// <=> p = sqrt31(1 / modulesCount)
|
// so we use a modulo of 1 / sqrt31(1 / modulesCount)
|
/** @type {WeakMap<Module, number>} */
|
const moduleBits = new WeakMap();
|
const modulesCount = compilation.modules.size;
|
|
// precalculate the modulo values for each bit
|
const modulo = 1 / (1 / modulesCount) ** (1 / 31);
|
/** @type {number[]} */
|
const modulos = Array.from(
|
{ length: 31 },
|
/**
|
* Handles the callback logic for this hook.
|
* @param {number} x x
|
* @param {number} i i
|
* @returns {number} result
|
*/
|
(x, i) => (modulo ** i) | 0
|
);
|
|
// iterate all modules to generate bit values
|
let i = 0;
|
for (const module of compilation.modules) {
|
let bit = 30;
|
while (i % modulos[bit] !== 0) {
|
bit--;
|
}
|
moduleBits.set(module, 1 << bit);
|
i++;
|
}
|
|
// iterate all chunks to generate bitmaps
|
/** @type {WeakMap<Chunk, number>} */
|
const chunkModulesHash = new WeakMap();
|
for (const chunk of chunks) {
|
let hash = 0;
|
for (const module of chunkGraph.getChunkModulesIterable(chunk)) {
|
hash |= /** @type {number} */ (moduleBits.get(module));
|
}
|
chunkModulesHash.set(chunk, hash);
|
}
|
|
for (const chunkA of chunks) {
|
const chunkAHash =
|
/** @type {number} */
|
(chunkModulesHash.get(chunkA));
|
const chunkAModulesCount = chunkGraph.getNumberOfChunkModules(chunkA);
|
if (chunkAModulesCount === 0) continue;
|
/** @type {undefined | Module} */
|
let bestModule;
|
for (const module of chunkGraph.getChunkModulesIterable(chunkA)) {
|
if (
|
bestModule === undefined ||
|
chunkGraph.getNumberOfModuleChunks(bestModule) >
|
chunkGraph.getNumberOfModuleChunks(module)
|
) {
|
bestModule = module;
|
}
|
}
|
loopB: for (const chunkB of chunkGraph.getModuleChunksIterable(
|
/** @type {Module} */ (bestModule)
|
)) {
|
// as we iterate the same iterables twice
|
// skip if we find ourselves
|
if (chunkA === chunkB) continue;
|
|
const chunkBModulesCount =
|
chunkGraph.getNumberOfChunkModules(chunkB);
|
|
// ids for empty chunks are not included
|
if (chunkBModulesCount === 0) continue;
|
|
// instead of swapping A and B just bail
|
// as we loop twice the current A will be B and B then A
|
if (chunkAModulesCount > chunkBModulesCount) continue;
|
|
// is chunkA in chunkB?
|
|
// we do a cheap check for the hash value
|
const chunkBHash =
|
/** @type {number} */
|
(chunkModulesHash.get(chunkB));
|
if ((chunkBHash & chunkAHash) !== chunkAHash) continue;
|
|
// compare all modules
|
for (const m of chunkGraph.getChunkModulesIterable(chunkA)) {
|
if (!chunkGraph.isModuleInChunk(m, chunkB)) continue loopB;
|
}
|
|
/** @type {ChunkId[]} */
|
(chunkB.ids).push(/** @type {ChunkId} */ (chunkA.id));
|
// https://github.com/webpack/webpack/issues/18837
|
/** @type {ChunkId[]} */
|
(chunkB.ids).sort(compareIds);
|
}
|
}
|
});
|
});
|
}
|
}
|
|
module.exports = FlagIncludedChunksPlugin;
|
