static getCompilationHooks(compilation) {
		let hooks = compilationHooksMap.get(compilation);
		if (hooks === undefined) {
			hooks = {
				exportsDefinitions: new SyncBailHook(["definitions", "module"])
			};
			compilationHooksMap.set(compilation, hooks);
		}
		return hooks;
	}
@param {Compilation} compilation the compilation
@returns {ConcatenateModuleHooks} the attached hooks