Idea: TokenSet instead of vararg array of token elements

[jansorg]

The generated parser uses varargs to find a matching token. For heavily used rules this is allocating a lot of memory.
I'm not sure if this is feasible, but creating a static TokenSet for the tokens instead of allocating an array for each invocation could reduce allocations (and thus GC) a lot.
Thank you for your consideration!

public static boolean process_substitution(PsiBuilder b, int l) {
    if (!recursion_guard_(b, l, "process_substitution")) return false;
// here, a static TokenSet could be passed to avoid the implicit array allocation
    if (!nextTokenIsFast(b, INPUT_PROCESS_SUBSTITUTION, OUTPUT_PROCESS_SUBSTITUTION)) return false;
//...
}