diff options
Diffstat (limited to 'backends/smt2/smtbmc.py')
| -rw-r--r-- | backends/smt2/smtbmc.py | 282 |
1 files changed, 209 insertions, 73 deletions
diff --git a/backends/smt2/smtbmc.py b/backends/smt2/smtbmc.py index 047fb6cde..4ad940551 100644 --- a/backends/smt2/smtbmc.py +++ b/backends/smt2/smtbmc.py @@ -983,7 +983,7 @@ def print_anyconsts_worker(mod, state, path): for fun, info in smt.modinfo[mod].anyconsts.items(): if info[1] is None: - print_msg("Value for anyconst in %s (%s): %d" % (path, info, smt.bv2int(smt.get("(|%s| %s)" % (fun, state))))) + print_msg("Value for anyconst in %s (%s): %d" % (path, info[0], smt.bv2int(smt.get("(|%s| %s)" % (fun, state))))) else: print_msg("Value for anyconst %s.%s (%s): %d" % (path, info[1], info[0], smt.bv2int(smt.get("(|%s| %s)" % (fun, state))))) @@ -1010,24 +1010,160 @@ def get_cover_list(mod, base): return cover_expr, cover_desc +states = list() +asserts_antecedent_cache = [list()] +asserts_consequent_cache = [list()] +asserts_cache_dirty = False + +def smt_state(step): + smt.write("(declare-fun s%d () |%s_s|)" % (step, topmod)) + states.append("s%d" % step) + +def smt_assert_antecedent(expr): + if expr == "true": + return + + smt.write("(assert %s)" % expr) + + global asserts_cache_dirty + asserts_cache_dirty = True + asserts_antecedent_cache[-1].append(expr) + +def smt_assert_consequent(expr): + if expr == "true": + return + + smt.write("(assert %s)" % expr) + + global asserts_cache_dirty + asserts_cache_dirty = True + asserts_consequent_cache[-1].append(expr) + +def smt_forall_assert(): + if not smt.forall: + return + + global asserts_cache_dirty + asserts_cache_dirty = False + + def make_assert_expr(asserts_cache): + expr = list() + for lst in asserts_cache: + expr += lst + + assert len(expr) != 0 + + if len(expr) == 1: + expr = expr[0] + else: + expr = "(and %s)" % (" ".join(expr)) + return expr + + antecedent_expr = make_assert_expr(asserts_antecedent_cache) + consequent_expr = make_assert_expr(asserts_consequent_cache) + + states_db = set(states) + used_states_db = set() + new_antecedent_expr = list() + new_consequent_expr = list() + assert_expr = list() + + def make_new_expr(new_expr, expr): + cursor = 0 + while cursor < len(expr): + l = 1 + if expr[cursor] in '|"': + while cursor+l+1 < len(expr) and expr[cursor] != expr[cursor+l]: + l += 1 + l += 1 + elif expr[cursor] not in '() ': + while cursor+l < len(expr) and expr[cursor+l] not in '|"() ': + l += 1 + + word = expr[cursor:cursor+l] + if word in states_db: + used_states_db.add(word) + word += "_" + + new_expr.append(word) + cursor += l + + make_new_expr(new_antecedent_expr, antecedent_expr) + make_new_expr(new_consequent_expr, consequent_expr) + + new_antecedent_expr = ["".join(new_antecedent_expr)] + new_consequent_expr = ["".join(new_consequent_expr)] + + if states[0] in used_states_db: + new_antecedent_expr.append("(|%s_ex_state_eq| %s %s_)" % (topmod, states[0], states[0])) + for s in states: + if s in used_states_db: + new_antecedent_expr.append("(|%s_ex_input_eq| %s %s_)" % (topmod, s, s)) + + if len(new_antecedent_expr) == 0: + new_antecedent_expr = "true" + elif len(new_antecedent_expr) == 1: + new_antecedent_expr = new_antecedent_expr[0] + else: + new_antecedent_expr = "(and %s)" % (" ".join(new_antecedent_expr)) + + if len(new_consequent_expr) == 0: + new_consequent_expr = "true" + elif len(new_consequent_expr) == 1: + new_consequent_expr = new_consequent_expr[0] + else: + new_consequent_expr = "(and %s)" % (" ".join(new_consequent_expr)) + + assert_expr.append("(assert (forall (") + first_state = True + for s in states: + if s in used_states_db: + assert_expr.append("%s(%s_ |%s_s|)" % ("" if first_state else " ", s, topmod)) + first_state = False + assert_expr.append(") (=> %s %s)))" % (new_antecedent_expr, new_consequent_expr)) + + smt.write("".join(assert_expr)) + +def smt_push(): + global asserts_cache_dirty + asserts_cache_dirty = True + asserts_antecedent_cache.append(list()) + asserts_consequent_cache.append(list()) + smt.write("(push 1)") + +def smt_pop(): + global asserts_cache_dirty + asserts_cache_dirty = True + asserts_antecedent_cache.pop() + asserts_consequent_cache.pop() + smt.write("(pop 1)") + +def smt_check_sat(): + if asserts_cache_dirty: + smt_forall_assert() + return smt.check_sat() if tempind: retstatus = False skip_counter = step_size for step in range(num_steps, -1, -1): - smt.write("(declare-fun s%d () |%s_s|)" % (step, topmod)) - smt.write("(assert (|%s_u| s%d))" % (topmod, step)) - smt.write("(assert (|%s_h| s%d))" % (topmod, step)) - smt.write("(assert (not (|%s_is| s%d)))" % (topmod, step)) - smt.write("(assert %s)" % get_constr_expr(constr_assumes, step)) + if smt.forall: + print_msg("Temporal induction not supported for exists-forall problems.") + break + + smt_state(step) + smt_assert_consequent("(|%s_u| s%d)" % (topmod, step)) + smt_assert_antecedent("(|%s_h| s%d)" % (topmod, step)) + smt_assert_antecedent("(not (|%s_is| s%d))" % (topmod, step)) + smt_assert_consequent(get_constr_expr(constr_assumes, step)) if step == num_steps: - smt.write("(assert (not (and (|%s_a| s%d) %s)))" % (topmod, step, get_constr_expr(constr_asserts, step))) + smt_assert_consequent("(not (and (|%s_a| s%d) %s))" % (topmod, step, get_constr_expr(constr_asserts, step))) else: - smt.write("(assert (|%s_t| s%d s%d))" % (topmod, step, step+1)) - smt.write("(assert (|%s_a| s%d))" % (topmod, step)) - smt.write("(assert %s)" % get_constr_expr(constr_asserts, step)) + smt_assert_antecedent("(|%s_t| s%d s%d)" % (topmod, step, step+1)) + smt_assert_consequent("(|%s_a| s%d)" % (topmod, step)) + smt_assert_consequent(get_constr_expr(constr_asserts, step)) if step > num_steps-skip_steps: print_msg("Skipping induction in step %d.." % (step)) @@ -1041,9 +1177,9 @@ if tempind: skip_counter = 0 print_msg("Trying induction in step %d.." % (step)) - if smt.check_sat() == "sat": + if smt_check_sat() == "sat": if step == 0: - print("%s Temporal induction failed!" % smt.timestamp()) + print_msg("Temporal induction failed!") print_anyconsts(num_steps) print_failed_asserts(num_steps) write_trace(step, num_steps+1, '%') @@ -1054,7 +1190,7 @@ if tempind: write_trace(step, num_steps+1, "%d" % step) else: - print("%s Temporal induction successful." % smt.timestamp()) + print_msg("Temporal induction successful.") retstatus = True break @@ -1079,42 +1215,42 @@ elif covermode: assert step_size == 1 while step < num_steps: - smt.write("(declare-fun s%d () |%s_s|)" % (step, topmod)) - smt.write("(assert (|%s_u| s%d))" % (topmod, step)) - smt.write("(assert (|%s_h| s%d))" % (topmod, step)) - smt.write("(assert %s)" % get_constr_expr(constr_assumes, step)) + smt_state(step) + smt_assert_consequent("(|%s_u| s%d)" % (topmod, step)) + smt_assert_antecedent("(|%s_h| s%d)" % (topmod, step)) + smt_assert_consequent(get_constr_expr(constr_assumes, step)) if step == 0: if noinit: - smt.write("(assert (not (|%s_is| s%d)))" % (topmod, step)) + smt_assert_antecedent("(not (|%s_is| s%d))" % (topmod, step)) else: - smt.write("(assert (|%s_i| s0))" % (topmod)) - smt.write("(assert (|%s_is| s0))" % (topmod)) + smt_assert_antecedent("(|%s_i| s0)" % (topmod)) + smt_assert_antecedent("(|%s_is| s0)" % (topmod)) else: - smt.write("(assert (|%s_t| s%d s%d))" % (topmod, step-1, step)) - smt.write("(assert (not (|%s_is| s%d)))" % (topmod, step)) + smt_assert_antecedent("(|%s_t| s%d s%d)" % (topmod, step-1, step)) + smt_assert_antecedent("(not (|%s_is| s%d))" % (topmod, step)) while "1" in cover_mask: print_msg("Checking cover reachability in step %d.." % (step)) - smt.write("(push 1)") - smt.write("(assert (distinct (covers_%d s%d) #b%s))" % (coveridx, step, "0" * len(cover_desc))) + smt_push() + smt_assert_antecedent("(distinct (covers_%d s%d) #b%s)" % (coveridx, step, "0" * len(cover_desc))) - if smt.check_sat() == "unsat": - smt.write("(pop 1)") + if smt_check_sat() == "unsat": + smt_pop() break if append_steps > 0: for i in range(step+1, step+1+append_steps): print_msg("Appending additional step %d." % i) - smt.write("(declare-fun s%d () |%s_s|)" % (i, topmod)) - smt.write("(assert (not (|%s_is| s%d)))" % (topmod, i)) - smt.write("(assert (|%s_u| s%d))" % (topmod, i)) - smt.write("(assert (|%s_h| s%d))" % (topmod, i)) - smt.write("(assert (|%s_t| s%d s%d))" % (topmod, i-1, i)) - smt.write("(assert %s)" % get_constr_expr(constr_assumes, i)) + smt_state(i) + smt_assert_antecedent("(not (|%s_is| s%d))" % (topmod, i)) + smt_assert_consequent("(|%s_u| s%d)" % (topmod, i)) + smt_assert_antecedent("(|%s_h| s%d)" % (topmod, i)) + smt_assert_antecedent("(|%s_t| s%d s%d)" % (topmod, i-1, i)) + smt_assert_consequent(get_constr_expr(constr_assumes, i)) print_msg("Re-solving with appended steps..") - assert smt.check_sat() == "sat" + assert smt_check_sat() == "sat" reached_covers = smt.bv2bin(smt.get("(covers_%d s%d)" % (coveridx, step))) assert len(reached_covers) == len(cover_desc) @@ -1141,7 +1277,7 @@ elif covermode: break coveridx += 1 - smt.write("(pop 1)") + smt_pop() smt.write("(define-fun covers_%d ((state |%s_s|)) (_ BitVec %d) (bvand (covers_%d state) #b%s))" % (coveridx, topmod, len(cover_desc), coveridx-1, cover_mask)) if found_failed_assert: @@ -1162,27 +1298,27 @@ else: # not tempind, covermode step = 0 retstatus = True while step < num_steps: - smt.write("(declare-fun s%d () |%s_s|)" % (step, topmod)) - smt.write("(assert (|%s_u| s%d))" % (topmod, step)) - smt.write("(assert (|%s_h| s%d))" % (topmod, step)) - smt.write("(assert %s)" % get_constr_expr(constr_assumes, step)) + smt_state(step) + smt_assert_consequent("(|%s_u| s%d)" % (topmod, step)) + smt_assert_antecedent("(|%s_h| s%d)" % (topmod, step)) + smt_assert_consequent(get_constr_expr(constr_assumes, step)) if step == 0: if noinit: - smt.write("(assert (not (|%s_is| s%d)))" % (topmod, step)) + smt_assert_antecedent("(not (|%s_is| s%d))" % (topmod, step)) else: - smt.write("(assert (|%s_i| s0))" % (topmod)) - smt.write("(assert (|%s_is| s0))" % (topmod)) + smt_assert_antecedent("(|%s_i| s0)" % (topmod)) + smt_assert_antecedent("(|%s_is| s0)" % (topmod)) else: - smt.write("(assert (|%s_t| s%d s%d))" % (topmod, step-1, step)) - smt.write("(assert (not (|%s_is| s%d)))" % (topmod, step)) + smt_assert_antecedent("(|%s_t| s%d s%d)" % (topmod, step-1, step)) + smt_assert_antecedent("(not (|%s_is| s%d))" % (topmod, step)) if step < skip_steps: if assume_skipped is not None and step >= assume_skipped: print_msg("Skipping step %d (and assuming pass).." % (step)) - smt.write("(assert (|%s_a| s%d))" % (topmod, step)) - smt.write("(assert %s)" % get_constr_expr(constr_asserts, step)) + smt_assert_consequent("(|%s_a| s%d)" % (topmod, step)) + smt_assert_consequent(get_constr_expr(constr_asserts, step)) else: print_msg("Skipping step %d.." % (step)) step += 1 @@ -1191,12 +1327,12 @@ else: # not tempind, covermode last_check_step = step for i in range(1, step_size): if step+i < num_steps: - smt.write("(declare-fun s%d () |%s_s|)" % (step+i, topmod)) - smt.write("(assert (not (|%s_is| s%d)))" % (topmod, step+i)) - smt.write("(assert (|%s_u| s%d))" % (topmod, step+i)) - smt.write("(assert (|%s_h| s%d))" % (topmod, step+i)) - smt.write("(assert (|%s_t| s%d s%d))" % (topmod, step+i-1, step+i)) - smt.write("(assert %s)" % get_constr_expr(constr_assumes, step+i)) + smt_state(step+i) + smt_assert_antecedent("(not (|%s_is| s%d))" % (topmod, step+i)) + smt_assert_consequent("(|%s_u| s%d)" % (topmod, step+i)) + smt_assert_antecedent("(|%s_h| s%d)" % (topmod, step+i)) + smt_assert_antecedent("(|%s_t| s%d s%d)" % (topmod, step+i-1, step+i)) + smt_assert_consequent(get_constr_expr(constr_assumes, step+i)) last_check_step = step+i if not gentrace: @@ -1206,7 +1342,7 @@ else: # not tempind, covermode else: print_msg("Checking assumptions in steps %d to %d.." % (step, last_check_step)) - if smt.check_sat() == "unsat": + if smt_check_sat() == "unsat": print("%s Warmup failed!" % smt.timestamp()) retstatus = False break @@ -1216,23 +1352,23 @@ else: # not tempind, covermode print_msg("Checking assertions in step %d.." % (step)) else: print_msg("Checking assertions in steps %d to %d.." % (step, last_check_step)) - smt.write("(push 1)") + smt_push() - smt.write("(assert (not (and %s)))" % " ".join(["(|%s_a| s%d)" % (topmod, i) for i in range(step, last_check_step+1)] + + smt_assert_consequent("(not (and %s))" % " ".join(["(|%s_a| s%d)" % (topmod, i) for i in range(step, last_check_step+1)] + [get_constr_expr(constr_asserts, i) for i in range(step, last_check_step+1)])) - if smt.check_sat() == "sat": + if smt_check_sat() == "sat": print("%s BMC failed!" % smt.timestamp()) if append_steps > 0: for i in range(last_check_step+1, last_check_step+1+append_steps): print_msg("Appending additional step %d." % i) - smt.write("(declare-fun s%d () |%s_s|)" % (i, topmod)) - smt.write("(assert (not (|%s_is| s%d)))" % (topmod, i)) - smt.write("(assert (|%s_u| s%d))" % (topmod, i)) - smt.write("(assert (|%s_h| s%d))" % (topmod, i)) - smt.write("(assert (|%s_t| s%d s%d))" % (topmod, i-1, i)) - smt.write("(assert %s)" % get_constr_expr(constr_assumes, i)) - assert smt.check_sat() == "sat" + smt_state(i) + smt_assert_antecedent("(not (|%s_is| s%d))" % (topmod, i)) + smt_assert_consequent("(|%s_u| s%d)" % (topmod, i)) + smt_assert_antecedent("(|%s_h| s%d)" % (topmod, i)) + smt_assert_antecedent("(|%s_t| s%d s%d)" % (topmod, i-1, i)) + smt_assert_consequent(get_constr_expr(constr_assumes, i)) + assert smt_check_sat() == "sat" print_anyconsts(step) for i in range(step, last_check_step+1): print_failed_asserts(i) @@ -1240,12 +1376,12 @@ else: # not tempind, covermode retstatus = False break - smt.write("(pop 1)") + smt_pop() if (constr_final_start is not None) or (last_check_step+1 != num_steps): for i in range(step, last_check_step+1): - smt.write("(assert (|%s_a| s%d))" % (topmod, i)) - smt.write("(assert %s)" % get_constr_expr(constr_asserts, i)) + smt_assert_consequent("(|%s_a| s%d)" % (topmod, i)) + smt_assert_consequent(get_constr_expr(constr_asserts, i)) if constr_final_start is not None: for i in range(step, last_check_step+1): @@ -1253,12 +1389,12 @@ else: # not tempind, covermode continue print_msg("Checking final constraints in step %d.." % (i)) - smt.write("(push 1)") + smt_push() - smt.write("(assert %s)" % get_constr_expr(constr_assumes, i, final=True)) - smt.write("(assert (not %s))" % get_constr_expr(constr_asserts, i, final=True)) + smt_assert_consequent(get_constr_expr(constr_assumes, i, final=True)) + smt_assert_consequent("(not %s)" % get_constr_expr(constr_asserts, i, final=True)) - if smt.check_sat() == "sat": + if smt_check_sat() == "sat": print("%s BMC failed!" % smt.timestamp()) print_anyconsts(i) print_failed_asserts(i, final=True) @@ -1266,17 +1402,17 @@ else: # not tempind, covermode retstatus = False break - smt.write("(pop 1)") + smt_pop() if not retstatus: break else: # gentrace for i in range(step, last_check_step+1): - smt.write("(assert (|%s_a| s%d))" % (topmod, i)) - smt.write("(assert %s)" % get_constr_expr(constr_asserts, i)) + smt_assert_consequent("(|%s_a| s%d)" % (topmod, i)) + smt_assert_consequent(get_constr_expr(constr_asserts, i)) print_msg("Solving for step %d.." % (last_check_step)) - if smt.check_sat() != "sat": + if smt_check_sat() != "sat": print("%s No solution found!" % smt.timestamp()) retstatus = False break |