#!/usr/bin/python3
#
#  Copyright (c) 2020 Peter Hsu.  All Rights Reserved.  See LICENCE file for details.
#

import sys

if len(sys.argv) != 2:
    print("usage:  ./make_cache <ways associativity>")
    exit(0)

N = int(sys.argv[1])
filename = 'lru_fsm_{:d}way.h'.format(N)
print('Making', N, 'way associative cache in file ', filename)

def cacheHit(state, hit):
    new = state.copy()
#    print("cacheHit(", state, hit, ")")
    way = new.pop(hit)
    new.insert(0, way)
    return new

def makeKey(state):
    key = '-'
    key = key.join(state)
    return key

def factorial(state):
    key = makeKey(state)
    for i in range(N):
        nextState = cacheHit(state, i)
        nextKey = makeKey(nextState)
        if nextKey not in table:
            table[nextKey] = [ None ]*N
            factorial(nextState)
        table[key][i] = nextKey

initial = []
for i in range(N-1, -1, -1):
    initial.append(str(i))
table = {}
table[makeKey(initial)] = [ None ]*N
factorial(initial)

number = {}
k = 0
for key in sorted(table):
    number[key] = k
    k += 1



f = open(filename, 'w');
f.write('struct lru_fsm_t cache_fsm_{:d}way[] = {{\n'.format(N))
f.write('/* Header */\t{{ {:d}, {:3d} }}, /* Ways, Number of states */\n'.format(int(sys.argv[1]), len(table)))

k = 0
for key in sorted(table):
    ways = key.split('-')
    for (i, ww) in enumerate(ways):
        w = int(ww)
        ns = number[table[key][i]]
        if ns == k:
            f.write('/* {:2d} */'.format(k))
        else:
            f.write('\t')
        f.write('\t{{ {:d}, {:3d}*{:d} }}, /* {:s} */\n'.format(w, ns, N, table[key][i]))
        lru_w = w
        lru_i = i
    k += 1

f.write('};\n')

f.close()
exit(0)