New feature in SAT solving script: weak decomposition

other/decompose_fsm_optimise.py

@@ -3,6 +3,7 @@ from pysat.card import ITotalizer
 from pysat.formula import IDPool
 from pysat.formula import CNF
 
+import signal
 import math
 import argparse
 
@@ -10,17 +11,22 @@ import argparse
 # Stap 1: pip3 install python-sat
 # Stap 2: python3 decompose_fsm.py -h
 
+timeout = False
+timeout_seconds = 3*60
+record_sizes = False
+record_file = './results/log.txt'
+
 parser = argparse.ArgumentParser(description="Decomposes a FSM into smaller components by remapping its outputs. Uses a SAT solver.")
 parser.add_argument('-c', '--components', type=int, default=2, help='number of components')
+parser.add_argument('-w', '--weak', default=False, action="store_true", help='look for weak decomposition')
 parser.add_argument('--add-state-trans', default=False, action="store_true", help='adds state transitivity constraints')
 parser.add_argument('-v', '--verbose', default=False, action="store_true", help='prints more info')
 parser.add_argument('filename', help='path to .dot file')
 args = parser.parse_args()
 
-# als de de total_size te laag is => UNSAT => duurt lang
+# Aantal componenten. c = 1 is zinloos, maar zou moeten werken
 c = args.components
-
+assert c >= 1
-assert c >= 1           # c = 1 is zinloos, maar zou moeten werken
 
 
 ###################################
@@ -86,8 +92,18 @@ with open(args.filename) as file:
     print(machine)
 
 N = len(machine.states)
-print(f'Initial size: {N}')
+print(f'Input FSM: {N} states, {len(machine.inputs)} inputs, and {len(machine.outputs)} outputs')
 
+if timeout:
+  def timeout_handler(signum, frame):
+    with open(record_file, 'a') as file:
+      last_two_comps = '/'.join(args.filename.split('/')[-2:])
+      file.write(f'{last_two_comps}\t{N}\t{len(machine.inputs)}\t{len(machine.outputs)}\t{args.weak}\t{c}\tTIMEOUT\n')
+    print('TIMEOUT')
+    exit()
+
+  signal.signal(signal.SIGALRM, timeout_handler)
+  signal.alarm(timeout_seconds)
 
 ###################################
 # Utility functions
@@ -240,12 +256,26 @@ for rid in rids:
     progress.add()
 
 # Tot slot willen we weinig representanten. Dit doen we met een "atmost"
-# formule. Idealiter zoeken we naar de total_size, maar die staat nu vast.
+# formule. We gaan een binaire zoek doen met incremental sat solving.
+rhs = None
+if args.weak:
+  lower_bound = int(math.floor((N-1)**(1/c)))
+  upper_bound = int(N)
+  print(f'weak size constraints {lower_bound} {upper_bound}')
+  rhs = []
+  for rid in rids:
+    with ITotalizer([var_state_rep(rid, sx) for sx in machine.states], ubound=upper_bound, top_id=vpool.top) as cnf_optim:
+      vpool.occupy(vpool.top + 1, cnf_optim.top_id)
+      vpool.top = cnf_optim.top_id
+      cnf.extend(cnf_optim.cnf.clauses)
+      rhs.append(cnf_optim.rhs)
+else:
   lower_bound = int(math.floor(c * (N-1)**(1/c)))
   upper_bound = int(N + c - 1)
   print(f'size constraints {lower_bound} {upper_bound}')
-cnf_optim = ITotalizer([var_state_rep(rid, sx) for rid in rids for sx in machine.states], ubound=upper_bound, top_id=vpool.top)
+  with ITotalizer([var_state_rep(rid, sx) for rid in rids for sx in machine.states], ubound=upper_bound, top_id=vpool.top) as cnf_optim:
     cnf.extend(cnf_optim.cnf.clauses)
+    rhs = cnf_optim.rhs
 
 ##################################
 # Probleem oplossen met solver :-)
@@ -253,24 +283,35 @@ print('Start solving')
 print('- copying formula')
 with Solver(bootstrap_with=cnf) as solver:
   print('===============')
+  sat = None
   while upper_bound - lower_bound >= 2:
     mid_size = int((lower_bound + upper_bound) / 2)
-    print(f'Trying {lower_bound} < {mid_size} < {upper_bound}')
+    print(f'Trying {lower_bound} < {mid_size} < {upper_bound}', end='', flush=True)
-    sat = solver.solve(assumptions=[-cnf_optim.rhs[mid_size]])
+    if args.weak:
+      assumptions = [-rhs[rid][mid_size] for rid in rids]
+      sat = solver.solve(assumptions=assumptions)
+    else:
+      sat = solver.solve(assumptions=[-rhs[mid_size]])
     if sat:
+      print('\tdown')
       upper_bound = mid_size
       continue
     else:
+      print('\tup')
       lower_bound = mid_size
       continue
 
-  total_size = upper_bound
+  bound = upper_bound
-  print(f'done searching, found size = {total_size}')
+  print(f'done searching, found bound = {bound}')
-  sat = solver.solve(assumptions=[-cnf_optim.rhs[total_size]])
+
+  if args.weak:
+    assumptions = [-rhs[rid][bound] for rid in rids]
+    sat = solver.solve(assumptions=assumptions)
+  else:
+    sat = solver.solve(assumptions=[-rhs[bound]])
   assert sat
 
   # Even omzetten in een makkelijkere data structuur
-  print('- get model')
   m = solver.get_model()
   model = {}
   for l in m:
@@ -286,20 +327,23 @@ with Solver(bootstrap_with=cnf) as solver:
       print(f'State relation {rid}:')
       print_eqrel(lambda x, y: model[var_state_rel(rid, x, y)], machine.states)
 
-  # print equivalence classes
+  # Precieze groottes van elk component tellen
-  count = 0
+  counts = []
   for rid in rids:
-    if args.verbose:
+    count = 0
-      print(f'component {rid}')
     # Eerst verzamelen we de representanten
     for s in machine.states:
       if model[var_state_rep(rid, s)]:
         count += 1
         if args.verbose:
-          print(f'- representative state {s}')
+          print(f'comp {rid} -> representative state {s}')
+    counts.append(count)
 
-  # count moet gelijk zijn aan cost (of kleiner)
+  print(f'Reduced sizes = {counts} = {sum(counts)}')
-  print(f'Reduced size = {count}')
+  if record_sizes:
+    with open(record_file, 'a') as file:
+      last_two_comps = '/'.join(args.filename.split('/')[-2:])
+      file.write(f'{last_two_comps}\t{N}\t{len(machine.inputs)}\t{len(machine.outputs)}\t{args.weak}\t{c}\t{sum(counts)}\t{sorted(counts, reverse=True)}\n')
 
   projections = {}
   for rid in rids:
@@ -321,7 +365,8 @@ with Solver(bootstrap_with=cnf) as solver:
           projections[rid][o] = f'cls_{rid}_{count}'
 
       if not others:
-        projections[rid][repr] = f'{repr}'
+        # Aangeven dat het een unieke output is
+        projections[rid][repr] = f'cls_{rid}_{count}_u'
 
       count += 1