def excluded_element(xs, args):
if isinstance(xs, EMap):
res = excluded_element(xs.e, args)
if res is not None:
bag, x = res
return (EMap(bag, xs.transform_function).with_type(xs.type), xs.transform_function.apply_to(x))
if isinstance(xs, EFilter):
arg = xs.predicate.arg
e = xs.predicate.body
if isinstance(e, EUnaryOp) and e.op == UOp.Not and isinstance(e.e, EBinOp) and e.e.op == "==":
e = EBinOp(e.e.e1, "!=", e.e.e2).with_type(BOOL)
if isinstance(e, EBinOp) and e.op == "!=":
arg_left = arg in free_vars(e.e1)
arg_right = arg in free_vars(e.e2)
if arg_left and not arg_right:
return (xs.e, EUnaryOp(UOp.The, find_one_or_fail(_simple_filter(xs.e, ELambda(arg, EEq(e.e1, e.e2)), args=args))).with_type(xs.type.elem_type))
if arg_right and not arg_left:
return (xs.e, EUnaryOp(UOp.The, find_one_or_fail(_simple_filter(xs.e, ELambda(arg, EEq(e.e1, e.e2)), args=args))).with_type(xs.type.elem_type))
return (xs.e, EFirst(find_one_or_fail(_simple_filter(xs.e, ELambda(xs.predicate.arg, ENot(xs.predicate.body)), args))))
if isinstance(xs, EBinOp) and xs.op == "-" and isinstance(xs.e2, ESingleton):
return (xs.e1, xs.e2.e)
if isinstance(xs, EBinOp) and xs.op == "-":
return (xs.e1, EFirst(xs.e2))
if isinstance(xs, EBinOp) and xs.op == "+" and isinstance(xs.e1, EListSlice) and isinstance(xs.e2, EListSlice):
for e1, e2 in [(xs.e1, xs.e2), (xs.e2, xs.e1)]:
if e1.e == e2.e and e1.start == ZERO and e2.start == EBinOp(e1.end, "+", ONE) and is_lenof(e2.end, e2.e):
return (e1.e, EListGet(e1.e, e1.end).with_type(xs.type.elem_type))
return None
def test_edeepin(self):
ht = THandle("H", INT)
hb = EVar("hb").with_type(TBag(ht))
h = fresh_var(ht, omit=free_vars(hb))
arg = fresh_var(ht, omit=free_vars(h)|free_vars(hb))
f1 = EDeepIn(h, hb)
f2 = EUnaryOp(UOp.Any, EMap(hb, ELambda(arg, EBinOp(arg, "===", h).with_type(BOOL))).with_type(BOOL_BAG)).with_type(BOOL)
self.assert_same(f1, f2)
def make_subgoal(e, a=[], docstring=None):
if skip_stateless_synthesis.value and not any(v in ctx for v in free_vars(e)):
return e
query_name = fresh_name("query")
query = syntax.Query(query_name, syntax.Visibility.Internal, [], assumptions + a, e, docstring)
query_vars = [v for v in free_vars(query) if v not in ctx]
query.args = [(arg.id, arg.type) for arg in query_vars]
subgoals.append(query)
return syntax.ECall(query_name, tuple(query_vars)).with_type(e.type)
def retypecheck(exp, env : {str : syntax.Type} = None, fenv = None):
"""Add or fix the .type annotations on the given tree.
Returns True or False to indicate success or failure. If it fails, it
prints type errors to stdout.
Unlike `typecheck`, this procedure attempts to guess the types of variables
and functions in the expression using their .type annotations. The `env`
dictionary overrides these guesses and forces variables to be annotated with
a particular type.
"""
if env is None:
env = { v.id:v.type for v in free_vars(exp) }
if fenv is not None:
fenv = { f : (tuple(ty.arg_types), ty.ret_type) for f, ty in fenv.items() }
else:
fenv = { }
for e in all_exps(exp):
if isinstance(e, syntax.EEnumEntry):
env[e.name] = e.type
if isinstance(e, syntax.ECall):
if e.func not in fenv:
fenv[e.func] = (tuple(arg.type for arg in e.args), e.type)
errs = typecheck(exp, env=env, fenv=fenv)
if errs:
print("errors")
for e in errs:
print(" --> {}".format(e))
return not errs
def optimized_in(x, xs):
if isinstance(xs, EStateVar):
m = EMakeMap2(xs.e, mk_lambda(x.type, lambda x: ETRUE)).with_type(TMap(x.type, BOOL))
m = EStateVar(m).with_type(m.type)
return EHasKey(m, x).with_type(BOOL)
elif isinstance(xs, EBinOp) and xs.op == "-" and isinstance(xs.e1, EStateVar) and isinstance(xs.e2, ESingleton):
return optimized_cond(optimized_eq(x, xs.e2.e),
EGt(optimized_count(x, xs.e1), ONE),
optimized_in(x, xs.e1)).with_type(BOOL)
elif isinstance(xs, EBinOp) and xs.op == "-":
return EGt(optimized_count(x, xs.e1), optimized_count(x, xs.e2))
elif isinstance(xs, EBinOp) and xs.op == "+":
return EAny([
optimized_in(x, xs.e1),
optimized_in(x, xs.e2)])
elif isinstance(xs, ECond):
return optimized_cond(xs.cond,
optimized_in(x, xs.then_branch),
optimized_in(x, xs.else_branch)).with_type(BOOL)
elif isinstance(xs, EFilter):
return EAll([xs.predicate.apply_to(x), optimized_in(x, xs.e)])
elif isinstance(xs, EMap) and xs.transform_function.arg not in free_vars(x):
return optimized_any_matches(xs.e, ELambda(xs.transform_function.arg, optimized_eq(xs.transform_function.body, x)))
elif isinstance(xs, ESingleton):
return optimized_eq(x, xs.e)
elif isinstance(xs, EEmptyList):
return EFALSE
else:
return EBinOp(x, BOp.In, xs).with_type(BOOL)
def deps(thing):
if isinstance(thing, str):
yield from free_vars(self.query_impls[thing])
elif isinstance(thing, EVar):
for op in self.op_specs:
yield self.updates[(thing, op.name)]
elif isinstance(thing, Stm):
yield from self.queries_used_by(thing)
else:
raise ValueError(repr(thing))
def generalize(self, fvs):
if self.var not in fvs:
return self._parent.generalize(fvs)
new_parent = self._parent.generalize(fvs - { self.var } | free_vars(self.bag))
if new_parent is self._parent:
return self
return UnderBinder(
new_parent,
self.var,
self.bag,
self.pool)
def fold_into_map(e, context):
fvs = free_vars(e)
state_vars = [v for v, p in context.vars() if p == STATE_POOL]
for subexp, subcontext, subpool in all_subexpressions_with_context_information(e, context, RUNTIME_POOL):
if isinstance(subexp, EMapGet) and isinstance(subexp.map, EStateVar):
map = subexp.map.e
key = subexp.key
key_type = key.type
value_type = subexp.type
# e is of the form `... EStateVar(map)[key] ...`
arg = fresh_var(subexp.type, omit=fvs)
func = ELambda(arg, replace(
e, context, RUNTIME_POOL,
subexp, subcontext, subpool,
arg))
if not all(v in state_vars for v in free_vars(func)):
continue
func = strip_EStateVar(func)
new_map = map_values(map, func.apply_to)
yield EMapGet(EStateVar(new_map).with_type(new_map.type), key).with_type(e.type)
def fold_into_map(e, context):
fvs = free_vars(e)
state_vars = [v for v, p in context.vars() if p == STATE_POOL]
for subexp, subcontext, subpool in shred(e, context, RUNTIME_POOL):
if isinstance(subexp, EMapGet) and isinstance(subexp.map, EStateVar):
map = subexp.map.e
key = subexp.key
key_type = key.type
value_type = subexp.type
# e is of the form `... EStateVar(map)[key] ...`
arg = fresh_var(subexp.type, omit=fvs)
func = ELambda(
arg,
replace(e, context, RUNTIME_POOL, subexp, subcontext, subpool,
arg))
if not all(v in state_vars for v in free_vars(func)):
continue
func = strip_EStateVar(func)
new_map = map_values(map, func.apply_to)
yield EMapGet(EStateVar(new_map).with_type(new_map.type),
key).with_type(e.type)
def add_query(self, q : Query):
"""
Given a query in terms of abstract state, add an initial concrete
implementation.
"""
print("Adding query {}...".format(q.name))
self.query_specs.append(q)
fvs = free_vars(q)
# initial rep
qargs = set(EVar(a).with_type(t) for (a, t) in q.args)
rep, ret = tease_apart(wrap_naked_statevars(q.ret, self.abstract_state))
self.set_impl(q, rep, ret)
def adapt(self, e : Exp, ctx, e_fvs=None) -> Exp:
if self == ctx:
return e
if e_fvs is None:
e_fvs = free_vars(e)
if isinstance(ctx, UnderBinder):
if ctx.var not in e_fvs:
return self.adapt(e, ctx.parent(), e_fvs=e_fvs)
if alpha_equivalent(self.bag, self._parent.adapt(ctx.bag, ctx._parent)):
e = self._parent.adapt(e, ctx._parent, e_fvs=e_fvs)
return subst(e, { ctx.var.id : self.var })
return self._parent.adapt(e, ctx, e_fvs=e_fvs)
def __init__(self,
ctx: SynthCtx,
state: [EVar],
assumptions: [Exp],
q: Query,
k,
hints: [Exp] = [],
examples: [dict] = None):
super().__init__()
self.ctx = ctx
self.state = state
self.assumptions = assumptions
self.q = shallow_copy(q)
assert all(
v in state for v in free_vars(q)
), "Oops, query looks malformed due to {}:\n{}\nfree_vars({})".format(
[v for v in free_vars(q) if v not in state], pprint(q), repr(q))
q.ret = wrap_naked_statevars(q.ret, OrderedSet(state))
self.hints = hints
self.examples = examples
self.k = k
def cleanup(self):
"""
Remove unused state, queries, and updates.
"""
def deps(thing):
if isinstance(thing, str):
yield from free_vars(self.query_impls[thing])
elif isinstance(thing, EVar):
for op in self.op_specs:
yield self.updates[(thing, op.name)]
elif isinstance(thing, Stm):
yield from self.queries_used_by(thing)
else:
raise ValueError(repr(thing))
g = DirectedGraph(nodes=itertools.chain(
self.query_impls.keys(),
(v for v, _ in self._concretization_functions),
self.updates.values()),
successors=deps)
roots = [
q.name for q in self.query_specs
if q.visibility == Visibility.Public
]
roots.extend(
itertools.chain(*[
self.queries_used_by(code)
for ((ht, op_name), code) in self.handle_updates.items()
]))
queries_to_keep = set(q for q in g.reachable_nodes(roots)
if isinstance(q, str))
# remove old specs
for q in list(self.query_specs):
if q.name not in queries_to_keep:
self.query_specs.remove(q)
# remove old implementations
for qname in list(self.query_impls.keys()):
if qname not in queries_to_keep:
del self.query_impls[qname]
# remove old state vars
self._concretization_functions = [
v for v in self._concretization_functions
if any(v[0] in free_vars(q) for q in self.query_impls.values())
]
# remove old method implementations
for k in list(self.updates.keys()):
v, op_name = k
if v not in [var for (var, exp) in self._concretization_functions]:
del self.updates[k]
def _simple_filter(xs, p, args):
if p.body == T:
return xs
if p.body == F:
return EEmptyList().with_type(xs.type)
if isinstance(xs, EEmptyList):
return xs
if isinstance(xs, EStateVar) and not any(v in args for v in free_vars(p)):
return EStateVar(EFilter(xs.e, strip_EStateVar(p)).with_type(
xs.type)).with_type(xs.type)
if isinstance(xs, EMapGet) and isinstance(
xs.map, EStateVar) and not any(v in args for v in free_vars(p)):
m = map_values(xs.map.e, lambda ys: _simple_filter(ys, p, args))
return EMapGet(EStateVar(m).with_type(m.type),
xs.key).with_type(xs.type)
if isinstance(xs, EBinOp) and xs.op == "+":
return EBinOp(_simple_filter(xs.e1, p, args), "+",
_simple_filter(xs.e2, p, args)).with_type(xs.type)
if isinstance(xs, EBinOp) and xs.op == "-":
return EBinOp(_simple_filter(xs.e1, p, args), "-",
_simple_filter(xs.e2, p, args)).with_type(xs.type)
if isinstance(p.body, EBinOp) and p.body.op == "==":
fvs2 = free_vars(p.body.e2)
fvs1 = free_vars(p.body.e1)
if p.arg in fvs1 and not any(
a in fvs1 for a in args) and p.arg not in fvs2 and isinstance(
xs, EStateVar):
k = fresh_var(p.body.e1.type)
e = EMapGet(
EStateVar(
EMakeMap2(
EMap(xs.e, ELambda(p.arg, p.body.e1)),
ELambda(
k, EFilter(xs.e, ELambda(p.arg, EEq(p.body.e1,
k)))))),
p.body.e2)
res = retypecheck(e)
assert res
return e
return EFilter(xs, p).with_type(xs.type)
def adapt(self, e: Exp, ctx, e_fvs=None) -> Exp:
if self == ctx:
return e
if e_fvs is None:
e_fvs = free_vars(e)
if isinstance(ctx, UnderBinder):
if ctx.var not in e_fvs:
return self.adapt(e, ctx.parent(), e_fvs=e_fvs)
if alpha_equivalent(self.bag,
self._parent.adapt(ctx.bag, ctx._parent)):
e = self._parent.adapt(e, ctx._parent, e_fvs=e_fvs)
return subst(e, {ctx.var.id: self.var})
return self._parent.adapt(e, ctx, e_fvs=e_fvs)
def retypecheck(exp, env=None):
from cozy.syntax_tools import free_vars
if env is None:
env = {v.id: v.type for v in free_vars(exp)}
for e in all_exps(exp):
if isinstance(e, syntax.EEnumEntry):
env[e.name] = e.type
errs = typecheck(exp, env=env)
if errs:
print("errors")
for e in errs:
print(" --> {}".format(e))
return not errs
def __init__(self,
ctx: SynthCtx,
state: [EVar],
assumptions: [Exp],
q: Query,
k,
hints: [Exp] = [],
funcs: {str: TFunc} = {}):
assert all(
v in state for v in free_vars(q)
), "Oops, query looks malformed due to {}:\n{}\nfree_vars({})".format(
[v for v in free_vars(q) if v not in state], pprint(q), repr(q))
super().__init__()
self.ctx = ctx
self.state = state
self.assumptions = assumptions
q = shallow_copy(q)
q.ret = wrap_naked_statevars(q.ret, OrderedSet(state))
self.q = q
self.hints = hints
self.k = k
self.funcs = OrderedDict(funcs)
def _satisfy(e, solver, assumptions):
"""
:param e: expression to test sat
:param solver: the default solver
:param assumptions: a list of expressions that are assumed true
Heuristic to decide whether e is satisfiable quickly.
it is a partial procedure: the possible outputs are a satisfying assignment or None (indicating unknown)
it is allowed to indicate unknown with an arbitrary exception
(in which case falling back to the symbolic solver is a reasonable choice)
"""
if isinstance(e, EUnaryOp) and e.op == "not" and isinstance(
e.e, EBinOp) and e.e.op == "==":
e1 = e.e.e1
e2 = e.e.e2
if isinstance(e1, EFlatMap) and isinstance(e2, EFlatMap):
lc1 = extract_listcomp(e1)
lc2 = extract_listcomp(e2)
if lc1 is not None and lc2 is not None:
cond1 = get_cond(lc1)
cond2 = get_cond(lc2)
sat1 = solver.satisfy(cond1)
sat2 = solver.satisfy(cond2)
if sat1 is None and sat2 is not None:
return {k: v for k, v in sat2.items() if k not in lc2["P"]}
if sat1 is not None and sat2 is None:
return {k: v for k, v in sat1.items() if k not in lc1["P"]}
iterables = [random_value(v.type) for v in free_vars(e)]
ids = [v.id for v in free_vars(e)]
for vs in product(*iterables):
assignments = {}
for id_, val in zip(ids, vs):
assignments[id_] = val
sat = eval(EAll([e] + assumptions), assignments)
if sat:
return assignments
return None
def _compare(self, e1: Exp, e2: Exp, context: Context):
e1_constant = not free_vars(e1) and not free_funcs(e1)
e2_constant = not free_vars(e2) and not free_funcs(e2)
if e1_constant and e2_constant:
e1v = eval(e1, {})
e2v = eval(e2, {})
event("comparison obvious on constants: {} vs {}".format(e1v, e2v))
return order_objects(e1v, e2v)
if alpha_equivalent(e1, e2):
event("shortcutting comparison of identical terms")
return Order.EQUAL
path_condition = EAll(context.path_conditions())
always_le = self.solver.valid(EImplies(path_condition, ELe(e1, e2)))
always_ge = self.solver.valid(EImplies(path_condition, EGe(e1, e2)))
if always_le and always_ge:
return Order.EQUAL
if always_le:
return Order.LT
if always_ge:
return Order.GT
return Order.AMBIGUOUS
def storage_size(e, freebies : [Exp] = []):
h = extension_handler(type(e.type))
if h is not None:
return h.storage_size(e, storage_size=storage_size)
if e in freebies:
return ZERO
elif e.type == BOOL:
return ONE
elif is_numeric(e.type) or isinstance(e.type, THandle):
return FOUR
elif isinstance(e.type, TEnum):
return TWO
elif isinstance(e.type, TNative):
return FOUR
elif isinstance(e.type, TString):
return TWENTY
elif isinstance(e.type, TTuple):
return ESum([storage_size(ETupleGet(e, n).with_type(t)) for (n, t) in enumerate(e.type.ts)])
elif isinstance(e.type, TRecord):
return ESum([storage_size(EGetField(e, f).with_type(t)) for (f, t) in e.type.fields])
elif is_collection(e.type):
v = fresh_var(e.type.elem_type, omit=free_vars(e))
return ESum([
FOUR,
EUnaryOp(UOp.Sum, EMap(e, ELambda(v, storage_size(v))).with_type(INT_BAG)).with_type(INT)])
elif isinstance(e.type, TMap):
k = fresh_var(e.type.k, omit=free_vars(e))
return ESum([
FOUR,
EUnaryOp(UOp.Sum, EMap(
EMapKeys(e).with_type(TBag(e.type.k)),
ELambda(k, ESum([
storage_size(k),
storage_size(EMapGet(e, k).with_type(e.type.v))]))).with_type(INT_BAG)).with_type(INT)])
else:
raise NotImplementedError(e.type)
def map_accelerate(e, state_vars, binders, args, cache, size):
for (_, arg, f, bound) in enumerate_fragments(strip_EStateVar(e)):
if any(v in state_vars for v in free_vars(arg)):
continue
for binder in (b for b in binders
if b.type == arg.type and b not in bound):
value = f(binder)
if any(v not in state_vars and v not in binders
for v in free_vars(value)):
continue
for bag in cache.find_collections(pool=STATE_POOL,
size=size,
of=arg.type):
if isinstance(bag, EEmptyList):
continue
m = EMakeMap2(bag,
ELambda(binder,
value)).with_type(TMap(arg.type, e.type))
assert not any(v in args for v in free_vars(m))
if any(v in binders for v in free_vars(m)):
continue
yield (m, STATE_POOL)
yield (EMapGet(EStateVar(m).with_type(m.type),
arg).with_type(e.type), RUNTIME_POOL)
def replace_get_value(e : syntax.Exp, ptr : syntax.Exp, new_value : syntax.Exp) -> syntax.Exp:
"""
Return an expression representing the value of `e` after writing
`new_value` to `ptr`.
This amounts to replacing all instances of `_.val` in `e` with
(_ == ptr) ? (new_value) : (_.val)
"""
t = ptr.type
fvs = free_vars(ptr) | free_vars(new_value)
class V(BottomUpRewriter):
def visit_ELambda(self, e):
if e.arg in fvs:
v = fresh_var(e.arg.type, omit=fvs)
e = syntax.ELambda(v, e.apply_to(v))
return syntax.ELambda(e.arg, self.visit(e.body))
def visit_EGetField(self, e):
ee = self.visit(e.e)
res = syntax.EGetField(ee, e.field_name).with_type(e.type)
if e.e.type == t and e.field_name == "val":
res = syntax.ECond(syntax.EEq(ee, ptr), new_value, res).with_type(e.type)
return res
return V().visit(e)
def retypecheck(exp, env=None):
if env is None:
env = { v.id:v.type for v in free_vars(exp) }
fenv = { }
for e in all_exps(exp):
if isinstance(e, syntax.EEnumEntry):
env[e.name] = e.type
if isinstance(e, syntax.ECall):
fenv[e.func] = (tuple(arg.type for arg in e.args), e.type)
errs = typecheck(exp, env=env, fenv=fenv)
if errs:
print("errors")
for e in errs:
print(" --> {}".format(e))
return not errs
def _possible_replacements(self, e, pool, cost):
"""
Yields watched expressions that appear as worse versions of the given
expression. There may be more than one.
"""
# return
free_binders = OrderedSet(v for v in free_vars(e) if v in self.binders)
for ctx in self._watched_contexts(pool, e.type):
watched_e = ctx.e
p = ctx.pool
r = ctx.replace_e_with
assert e.type == watched_e.type
assert p == pool
_on_exp(e, "considering replacement of", watched_e)
# if e.type != watched_e.type:
# # _on_exp(e, "wrong type")
# continue
# if p != pool:
# # _on_exp(e, "wrong pool")
# continue
if e == watched_e:
# _on_exp(e, "no change")
continue
unbound_binders = [b for b in free_binders if b not in ctx.bound_vars]
if unbound_binders:
_on_exp(e, "skipped exp with free binders", ", ".join(b.id for b in unbound_binders))
continue
if CHECK_SUBST_COST:
watched_cost = self.cost_model.cost(watched_e, pool=pool)
ordering = self.compare_costs(cost, watched_cost)
if ordering == Cost.WORSE:
_on_exp(e, "skipped worse replacement", pool_name(pool), watched_e)
continue
if ordering == Cost.UNORDERED:
_on_exp(e, "skipped equivalent replacement", pool_name(pool), watched_e)
# print(" e1 = {!r}".format(e))
# print(" e2 = {!r}".format(watched_e))
continue
# assert all(eval_bulk(self.assumptions, self.all_examples))
if all(eval_bulk(EEq(self.target, r(e)), self.all_examples)):
yield (watched_e, e, ctx.facts, r)
else:
_on_exp(e, "visited pointless replacement", watched_e)
def eval_bulk(e: Exp,
envs: [{
str: object
}],
use_default_values_for_undefined_vars: bool = False):
"""Evaluate an expression in many different environments.
This function accepts the same arguments as `eval`, but takes a list of
environments instead of just one.
The call
eval_bulk(e, envs)
is equivalent to
[eval(e, env) for env in envs].
However, using `eval_bulk` is much faster than repeatedly calling `eval` on
the same expression.
"""
e = purify(e)
if not envs:
return []
ops = []
vars = OrderedSet(free_vars_and_funcs(e))
types = {v.id: v.type for v in free_vars(e)}
vmap = {v: i for (i, v) in enumerate(vars)}
try:
envs = [[(env.get(v, mkval(types[v])) if
(use_default_values_for_undefined_vars
and v in types) else env[v]) for v in vars] for env in envs]
except KeyError:
import sys
print("OH NO", file=sys.stderr)
print("e = {}".format(pprint(e)), file=sys.stderr)
print(
"eval_bulk({!r}, {!r}, use_default_values_for_undefined_vars={!r})"
.format(e, envs, use_default_values_for_undefined_vars),
file=sys.stderr)
raise
_compile(e, vmap, ops)
return [_eval_compiled(ops, env) for env in envs]
def optimized_any_matches(xs, p):
if isinstance(xs, EEmptyList):
return EFALSE
if isinstance(xs, ESingleton):
return p.apply_to(xs.e)
if isinstance(xs, EMap):
return optimized_any_matches(xs.e, compose(p, xs.transform_function))
# exists filter (not-in xs) ys
if isinstance(p.body, EUnaryOp) and p.body.op == UOp.Not and isinstance(
p.body.e, EBinOp) and p.body.e.op == BOp.In:
if p.arg not in free_vars(p.body.e.e2):
# er, this only works when xs is a subset of ys
return EGt(optimized_len(xs), optimized_len(p.body.e.e2))
if isinstance(p.body, EBinOp) and p.body.op == BOp.Or:
return EAny([
optimized_any_matches(xs, ELambda(p.arg,
p.body.e1)).with_type(xs.type),
optimized_any_matches(xs, ELambda(p.arg,
p.body.e2)).with_type(xs.type)
])
if isinstance(xs, EFilter):
return optimized_any_matches(
xs.e, ELambda(p.arg, EAll([p.body,
xs.predicate.apply_to(p.arg)])))
if isinstance(xs, EBinOp) and xs.op == "+":
return EAny(
[optimized_any_matches(xs.e1, p),
optimized_any_matches(xs.e2, p)])
if isinstance(xs, EBinOp) and xs.op == "-":
return EAll([
optimized_any_matches(xs.e1, p),
ENot(optimized_any_matches(xs.e2, p))
])
if isinstance(xs, ECond):
return optimized_cond(xs.cond,
optimized_any_matches(xs.then_branch, p),
optimized_any_matches(xs.else_branch,
p)).with_type(BOOL)
return EUnaryOp(UOp.Exists,
EFilter(xs, p).with_type(xs.type)).with_type(BOOL)
def visit_ELambda(self, e):
if e.arg in binders_by_type[e.arg.type]:
return super().visit_ADT(e)
fvs = free_vars(e.body)
legal_repls = [ b for b in binders_by_type[e.arg.type] if b not in fvs ]
if not legal_repls:
if allow_add:
print("Adding aux binder {} and returning {}".format(e.arg, pprint(ELambda(e.arg, e.body))), file=sys.stderr)
binders_to_use.append(e.arg)
binders_by_type[e.arg.type].append(e.arg)
return ELambda(e.arg, self.visit(e.body))
else:
if throw:
print("No legal binder to use for {}".format(pprint(e)))
raise Exception(pprint(e))
else:
return ELambda(e.arg, self.visit(e.body))
b = legal_repls[0]
return ELambda(b, self.visit(subst(e.body, { e.arg.id : b })))
def _setup_handle_updates(self):
"""
This method creates update code for handle objects modified by each op.
Must be called once after all user-specified queries have been added.
"""
for op in self.op_specs:
print("Setting up handle updates for {}...".format(op.name))
handles = reachable_handles_at_method(self.spec, op)
# print("-"*60)
for t, bag in handles.items():
# print(" {} : {}".format(pprint(t), pprint(bag)))
h = fresh_var(t)
lval = EGetField(h, "val").with_type(t.value_type)
new_val = inc.mutate(lval, op.body)
# get set of modified handles
modified_handles = Query(
fresh_name("modified_handles"),
Visibility.Internal, [], op.assumptions,
EFilter(EUnaryOp(UOp.Distinct, bag).with_type(bag.type), ELambda(h, ENot(EEq(lval, new_val)))).with_type(bag.type),
"[{}] modified handles of type {}".format(op.name, pprint(t)))
query_vars = [v for v in free_vars(modified_handles) if v not in self.abstract_state]
modified_handles.args = [(arg.id, arg.type) for arg in query_vars]
# modify each one
subqueries = []
state_update_stm = inc.mutate_in_place(
lval,
lval,
op.body,
abstract_state=self.abstract_state,
assumptions=list(op.assumptions) + [EDeepIn(h, bag), EIn(h, modified_handles.ret)],
invariants=self.abstract_invariants,
subgoals_out=subqueries)
for sub_q in subqueries:
sub_q.docstring = "[{}] {}".format(op.name, sub_q.docstring)
state_update_stm = self._add_subquery(sub_q=sub_q, used_by=state_update_stm)
if state_update_stm != SNoOp():
state_update_stm = SForEach(h, ECall(modified_handles.name, query_vars).with_type(bag.type), state_update_stm)
state_update_stm = self._add_subquery(sub_q=modified_handles, used_by=state_update_stm)
self.handle_updates[(t, op.name)] = state_update_stm
def EMax(es):
es = make_random_access(es)
assert es
assert all(isinstance(e, Exp) for e in es), es
res = es[0]
t = res.type
fvs = set(v.id for v in free_vars(res))
for i in range(1, len(es)):
res = maybe_inline(res, lambda v1:
maybe_inline(es[i], lambda v2:
ECond(EGt(v1, v2), v1, v2).with_type(t)))
# v1 = fresh_var(res.type, omit=fvs)
# fvs.add(v1.id)
# v2 = fresh_var(res.type, omit=fvs)
# fvs.add(v2.id)
# fvs |= set(v.id for v in free_vars(es[i]))
# res = ELet(res, ELambda(v1,
# ELet(es[i], ELambda(v2,
# ECond(EGt(v1, v2), v1, v2).with_type(res.type))).with_type(res.type))).with_type(res.type)
# res = ECond(EGt(res, es[i]), res, es[i]).with_type(res.type)
return res
def eval_bulk(
e : Exp,
envs : [{str:object}],
use_default_values_for_undefined_vars : bool = False):
"""Evaluate an expression in many different environments.
This function accepts the same arguments as `eval`, but takes a list of
environments instead of just one.
The call
eval_bulk(e, envs)
is equivalent to
[eval(e, env) for env in envs].
However, using `eval_bulk` is much faster than repeatedly calling `eval` on
the same expression.
"""
if not envs:
return []
e = purify(e)
ops = []
types = { v.id : v.type for v in free_vars(e) }
vars = OrderedSet(itertools.chain(types.keys(), free_funcs(e).keys()))
vmap = { v : i for (i, v) in enumerate(vars) }
try:
envs = [ [(env.get(v, mkval(types[v])) if (use_default_values_for_undefined_vars and v in types) else env[v]) for v in vars] for env in envs ]
except KeyError:
import sys
print("OH NO", file=sys.stderr)
print("e = {}".format(pprint(e)), file=sys.stderr)
print("eval_bulk({!r}, {!r}, use_default_values_for_undefined_vars={!r})".format(e, envs, use_default_values_for_undefined_vars), file=sys.stderr)
raise
_compile(e, vmap, ops)
return [_eval_compiled(ops, env) for env in envs]
def _setup_handle_updates(self):
"""
This method creates update code for handle objects modified by each op.
Must be called once after all user-specified queries have been added.
"""
for op in self.op_specs:
print("Setting up handle updates for {}...".format(op.name))
handles = reachable_handles_at_method(self.spec, op)
# print("-"*60)
for t, bag in handles.items():
# print(" {} : {}".format(pprint(t), pprint(bag)))
h = fresh_var(t)
lval = EGetField(h, "val").with_type(t.value_type)
new_val = inc.mutate(lval, op.body)
# get set of modified handles
modified_handles = Query(
fresh_name("modified_handles"),
Visibility.Internal, [], op.assumptions,
EFilter(EUnaryOp(UOp.Distinct, bag).with_type(bag.type), ELambda(h, ENot(EEq(lval, new_val)))).with_type(bag.type),
"[{}] modified handles of type {}".format(op.name, pprint(t)))
query_vars = [v for v in free_vars(modified_handles) if v not in self.abstract_state]
modified_handles.args = [(arg.id, arg.type) for arg in query_vars]
# modify each one
subqueries = []
state_update_stm = inc.mutate_in_place(
lval,
lval,
op.body,
abstract_state=self.abstract_state,
assumptions=list(op.assumptions) + [EDeepIn(h, bag), EIn(h, modified_handles.ret)],
subgoals_out=subqueries)
for sub_q in subqueries:
sub_q.docstring = "[{}] {}".format(op.name, sub_q.docstring)
state_update_stm = self._add_subquery(sub_q=sub_q, used_by=state_update_stm)
if state_update_stm != SNoOp():
state_update_stm = SForEach(h, ECall(modified_handles.name, query_vars).with_type(bag.type), state_update_stm)
state_update_stm = self._add_subquery(sub_q=modified_handles, used_by=state_update_stm)
self.handle_updates[(t, op.name)] = state_update_stm
def optimized_map(xs, f, args):
res_type = type(xs.type)(f.body.type)
if f.arg == f.body:
yield xs
if isinstance(xs, ESingleton):
yield ESingleton(f.apply_to(xs.e)).with_type(res_type)
if isinstance(xs, EEmptyList):
yield EEmptyList().with_type(res_type)
if isinstance(xs, EStateVar) and not any(v in args for v in free_vars(f)):
yield EStateVar(EMap(xs.e, f).with_type(res_type)).with_type(res_type)
if isinstance(xs, EBinOp):
if xs.op in ("+", "-"):
for a in optimized_map(xs.e1, f, args):
for b in optimized_map(xs.e2, f, args):
yield EBinOp(a, xs.op, b).with_type(res_type)
if isinstance(f.body, ECond):
for true_elems in optimized_filter(xs, ELambda(f.arg, f.body.cond) , args=args):
for false_elems in optimized_filter(xs, ELambda(f.arg, ENot(f.body.cond)), args=args):
for a in optimized_map(true_elems, ELambda(f.arg, f.body.then_branch), args):
for b in optimized_map(false_elems, ELambda(f.arg, f.body.else_branch), args):
yield EBinOp(a, "+", b).with_type(res_type)
yield EMap(xs, f).with_type(res_type)
def optimized_map(xs, f, args):
res_type = type(xs.type)(f.body.type)
if f.arg == f.body:
yield xs
if isinstance(xs, ESingleton):
yield ESingleton(f.apply_to(xs.e)).with_type(res_type)
if isinstance(xs, EEmptyList):
yield EEmptyList().with_type(res_type)
if isinstance(xs, EStateVar) and not any(v in args for v in free_vars(f)):
yield EStateVar(EMap(xs.e, f).with_type(res_type)).with_type(res_type)
if isinstance(xs, EBinOp):
if xs.op in ("+", "-"):
for a in optimized_map(xs.e1, f, args):
for b in optimized_map(xs.e2, f, args):
yield EBinOp(a, xs.op, b).with_type(res_type)
if isinstance(f.body, ECond):
for true_elems in optimized_filter(xs, ELambda(f.arg, f.body.cond) , args=args):
for false_elems in optimized_filter(xs, ELambda(f.arg, ENot(f.body.cond)), args=args):
for a in optimized_map(true_elems, ELambda(f.arg, f.body.then_branch), args):
for b in optimized_map(false_elems, ELambda(f.arg, f.body.else_branch), args):
yield EBinOp(a, "+", b).with_type(res_type)
yield EMap(xs, f).with_type(res_type)
def __init__(self, parent : Context, v : EVar, bag : Exp, bag_pool : Pool):
"""Construct a context under a binder.
Parameters:
parent - the context of the enclosing lambda
v - the bound variable
bag - the bag that v must be a member of
bag_pool - the pool that the bag belongs to
`v`'s type annotation must be the same as the type of elements
in the bag.
`bag` must be legal in the parent context.
`v` must not already be described by the parent context.
"""
assert v.type == bag.type.elem_type
assert parent.legal_for(free_vars(bag)), "cannot create context for {} in {}, {}".format(v.id, pprint(bag), parent)
assert not any(v == vv for vv, p in parent.vars()), "binder {} already free in {}".format(v.id, parent)
self._parent = parent
self.var = v
self.bag = bag
self.pool = bag_pool
def __init__(self, parent : Context, v : EVar, bag : Exp, bag_pool : Pool):
"""Construct a context under a binder.
Parameters:
parent - the context of the enclosing lambda
v - the bound variable
bag - the bag that v must be a member of
bag_pool - the pool that the bag belongs to
`v`'s type annotation must be the same as the type of elements
in the bag.
`bag` must be legal in the parent context.
`v` must not already be described by the parent context.
"""
assert v.type == bag.type.t
assert parent.legal_for(free_vars(bag)), "cannot create context for {} in {}, {}".format(v.id, pprint(bag), parent)
assert not any(v == vv for vv, p in parent.vars()), "binder {} already free in {}".format(v.id, parent)
self._parent = parent
self.var = v
self.bag = bag
self.pool = bag_pool
def __init__(self,
examples,
cost_model: CostModel,
check_wf=None,
hints=None,
heuristics=None,
stop_callback=None):
self.examples = list(examples)
self.cost_model = cost_model
self.cache = {} # keys -> [exp]
self.seen = {} # (ctx, pool, fp) -> frontier, i.e. [exp]
self.in_progress = set()
if check_wf is None:
check_wf = lambda e, ctx, pool: True
self.check_wf = check_wf
self.hints = OrderedSet(
(e, ctx.generalize(free_vars(e)), p) for (e, ctx, p) in hints)
if heuristics is None:
heuristics = lambda e, ctx, pool: ()
self.heuristics = heuristics
if stop_callback is None:
stop_callback = lambda: False
self.stop_callback = stop_callback
def eval_bulk(e, envs, use_default_values_for_undefined_vars: bool = False):
e = purify(e)
if not envs:
return []
ops = []
vars = OrderedSet(free_vars_and_funcs(e))
types = {v.id: v.type for v in free_vars(e)}
vmap = {v: i for (i, v) in enumerate(vars)}
try:
envs = [[(env.get(v, mkval(types[v])) if
(use_default_values_for_undefined_vars
and v in types) else env[v]) for v in vars] for env in envs]
except KeyError:
import sys
print("OH NO", file=sys.stderr)
print("e = {}".format(pprint(e)), file=sys.stderr)
print(
"eval_bulk({!r}, {!r}, use_default_values_for_undefined_vars={!r})"
.format(e, envs, use_default_values_for_undefined_vars),
file=sys.stderr)
raise
_compile(e, vmap, ops)
return [_eval_compiled(ops, env) for env in envs]
def optimized_any_matches(xs, p):
if isinstance(xs, EEmptyList):
return EFALSE
if isinstance(xs, ESingleton):
return p.apply_to(xs.e)
if isinstance(xs, EMap):
return optimized_any_matches(xs.e, compose(p, xs.transform_function))
# exists filter (not-in xs) ys
if isinstance(p.body, EUnaryOp) and p.body.op == UOp.Not and isinstance(p.body.e, EBinOp) and p.body.e.op == BOp.In:
if p.arg not in free_vars(p.body.e.e2):
# er, this only works when xs is a subset of ys
return EGt(
optimized_len(xs),
optimized_len(p.body.e.e2))
if isinstance(p.body, EBinOp) and p.body.op == BOp.Or:
return EAny([
optimized_any_matches(xs, ELambda(p.arg, p.body.e1)).with_type(xs.type),
optimized_any_matches(xs, ELambda(p.arg, p.body.e2)).with_type(xs.type)])
if isinstance(xs, EFilter):
return optimized_any_matches(xs.e, ELambda(p.arg, EAll([p.body, xs.predicate.apply_to(p.arg)])))
if isinstance(xs, EBinOp) and xs.op == "+":
return EAny([optimized_any_matches(xs.e1, p), optimized_any_matches(xs.e2, p)])
if isinstance(xs, EBinOp) and xs.op == "-":
return EAll([
optimized_any_matches(xs.e1, p),
ENot(optimized_any_matches(xs.e2, p))])
if isinstance(xs, ECond):
return optimized_cond(xs.cond,
optimized_any_matches(xs.then_branch, p),
optimized_any_matches(xs.else_branch, p)).with_type(BOOL)
return EUnaryOp(UOp.Exists, EFilter(xs, p).with_type(xs.type)).with_type(BOOL)
def optimized_best(xs, keyfunc, op, args):
argbest = EArgMin if op == "<" else EArgMax
elem_type = xs.type.elem_type
key_type = keyfunc.body.type
if excluded_element(xs, args) is not None:
bag, x = excluded_element(xs, args)
if all(v not in args for v in free_vars(bag)):
heap_type, make_heap = (TMinHeap, EMakeMinHeap) if op == "<" else (TMaxHeap, EMakeMaxHeap)
bag = EStateVar(strip_EStateVar(bag)).with_type(bag.type)
h = make_heap(bag.e, keyfunc).with_type(heap_type(elem_type, key_type))
for prev_min in optimized_best(bag.e, keyfunc, op, args=args):
prev_min = EStateVar(prev_min).with_type(elem_type)
heap_peek = EHeapPeek2(EStateVar(h).with_type(h.type)).with_type(elem_type)
conds = [optimized_in(x, bag), optimized_eq(x, prev_min)]
if isinstance(x, EUnaryOp) and x.op == UOp.The:
conds = [optimized_exists(x.e)] + conds
yield optimized_cond(
EAll(conds),
heap_peek,
prev_min)
if isinstance(xs, EEmptyList):
yield construct_value(elem_type)
if isinstance(xs, ESingleton):
yield xs.e
if isinstance(xs, EBinOp) and xs.op == "+":
a_ex = optimized_exists(xs.e1)
b_ex = optimized_exists(xs.e2)
bag_type = TBag(xs.type.elem_type)
for a in optimized_best(xs.e1, keyfunc, op, args=args):
for b in optimized_best(xs.e2, keyfunc, op, args=args):
yield optimized_cond(a_ex,
optimized_cond(b_ex,
argbest(EBinOp(ESingleton(a).with_type(bag_type), "+", ESingleton(b).with_type(bag_type)).with_type(bag_type), keyfunc).with_type(elem_type),
a),
optimized_cond(b_ex, b, construct_value(elem_type)))
# if isinstance(xs.e1, EStateVar) or isinstance(xs.e2, EStateVar):
# sv, other = (xs.e1, xs.e2) if isinstance(xs.e1, EStateVar) else (xs.e2, xs.e1)
# sv_best = optimized_best(sv, keyfunc, op, args=args)
# yield optimized_cond(
# optimized_exists(sv),
# argbest(EBinOp(ESingleton(sv_best).with_type(xs.type), "+", other).with_type(xs.type), keyfunc).with_type(elem_type),
# optimized_best(other, keyfunc, op, args=args))
# else:
# parts = break_sum(xs)
# found = EFALSE
# best = construct_value(elem_type)
# for p in parts:
# ex = optimized_exists(p)
# best_here = optimized_best(p, keyfunc, op, args=args)
# best = optimized_cond(found,
# optimized_cond(ex,
# optimized_cond(EBinOp(keyfunc.apply_to(best_here), op, keyfunc.apply_to(best)).with_type(BOOL),
# best_here,
# best),
# best),
# best_here)
# found = EAny([found, ex])
# yield best
if isinstance(xs, EMap):
for b in optimized_best(xs.e, compose(keyfunc, xs.transform_function), op, args):
yield optimized_cond(optimized_exists(xs.e),
xs.transform_function.apply_to(b),
construct_value(elem_type))
if isinstance(xs, EStateVar) and not any(v in args for v in free_vars(keyfunc)):
yield EStateVar(argbest(xs.e, keyfunc).with_type(elem_type)).with_type(elem_type)
if isinstance(xs, ECond):
for a in optimized_best(xs.then_branch, keyfunc, op, args=args):
for b in optimized_best(xs.else_branch, keyfunc, op, args=args):
yield optimized_cond(xs.cond, a, b)
if isinstance(xs, EUnaryOp) and xs.op == UOp.Distinct:
yield from optimized_best(xs.e, keyfunc, op, args=args)
# if isinstance(xs, EFilter):
# yield optimized_cond(
# xs.predicate.apply_to(optimized_best(xs.e, keyfunc, op, args=args)),
# optimized_best(xs.e, keyfunc, op, args=args),
# argbest(xs, keyfunc).with_type(elem_type))
yield argbest(xs, keyfunc).with_type(elem_type)
def visit_Spec(self, spec : Spec, state_exps : { str : Exp }, sharing, abstract_state=()):
self.state_exps = state_exps
self.funcs = { f.name: f for f in spec.extern_funcs }
self.queries = { q.name: q for q in spec.methods if isinstance(q, Query) }
self.vars = set(e.id for e in all_exps(spec) if isinstance(e, EVar))
self.write("#pragma once\n")
self.write("#include <algorithm>\n")
self.write("#include <set>\n")
self.write("#include <functional>\n")
self.write("#include <vector>\n")
self.write("#include <unordered_set>\n")
self.write("#include <string>\n")
if self.use_qhash:
self.write("#include <QHash>\n")
else:
self.write("#include <unordered_map>\n")
if spec.header:
self.write("\n" + spec.header.strip() + "\n")
self.write("{}\nclass {} {{\n".format(
("\n" + spec.docstring) if spec.docstring else "",
spec.name))
self.write("public:\n")
print("Setting up auxiliary types...")
self.setup_types(spec, state_exps, sharing)
with self.indented():
for t, name in self.types.items():
self.define_type(spec.name, t, name, sharing)
self.begin_statement()
if isinstance(t, THandle):
# No overridden hash code! We use pointers instead.
continue
self.write("struct _Hash", name, " ")
with self.block():
self.write_stmt("typedef ", spec.name, "::", name, " argument_type;")
self.write_stmt("typedef std::size_t result_type;")
self.begin_statement()
self.write("result_type operator()(const argument_type& x) const noexcept ")
x = EVar("x").with_type(t)
if isinstance(t, TEnum):
fields = [EEnumToInt(x).with_type(INT)]
elif isinstance(t, TRecord):
fields = [EGetField(x, f).with_type(ft) for (f, ft) in t.fields]
elif isinstance(t, TTuple):
fields = [ETupleGet(x, n).with_type(tt) for (n, tt) in enumerate(t.ts)]
else:
raise NotImplementedError(t)
with self.block():
self.visit(self.compute_hash(fields))
self.end_statement()
self.write(";")
self.end_statement()
print("Setting up member variables...")
self.write("protected:\n")
with self.indented():
for name, t in spec.statevars:
self.statevar_name = name
self.declare_field(name, t)
self.write("public:\n")
with self.indented():
print("Generating constructors...")
# default constructor
self.begin_statement()
self.write("inline ", spec.name, "() ")
with self.block():
for name, t in spec.statevars:
initial_value = state_exps[name]
fvs = free_vars(initial_value)
initial_value = subst(initial_value, {v.id : evaluation.construct_value(v.type) for v in fvs})
stm = simplify_and_optimize(SAssign(EVar(name).with_type(t), initial_value))
self.visit(stm)
self.end_statement()
# explicit constructor
if abstract_state:
self.begin_statement()
self.write("explicit inline ", spec.name, "(")
self.visit_args(abstract_state)
self.write(") ")
with self.block():
for name, t in spec.statevars:
initial_value = state_exps[name]
self.visit(simplify_and_optimize(SAssign(EVar(name).with_type(t), initial_value)))
self.end_statement()
# disable copy constructor (TODO: support this in the future?)
self.begin_statement()
self.write(spec.name, "(const ", spec.name, "& other) = delete;")
self.end_statement()
# generate methods
for op in spec.methods:
print("Generating method {}...".format(op.name))
self.visit(op)
self.write("};\n")
if spec.footer:
self.write("\n", spec.footer)
if not spec.footer.endswith("\n"):
self.write("\n")
def possibly_useful_nonrecursive(solver, e : Exp, context : Context, pool = RUNTIME_POOL, assumptions : Exp = ETRUE, ops : [Op] = ()) -> bool:
"""Heuristic filter to ignore expressions that are almost certainly useless."""
state_vars = OrderedSet(v for v, p in context.vars() if p == STATE_POOL)
args = OrderedSet(v for v, p in context.vars() if p == RUNTIME_POOL)
assumptions = EAll([assumptions, context.path_condition()])
at_runtime = pool == RUNTIME_POOL
h = extension_handler(type(e))
if h is not None:
res = h.possibly_useful(e, context, pool, assumptions, ops, solver)
if not res:
return res
if isinstance(e, EStateVar) and not free_vars(e.e):
return No("constant value in state position")
if (isinstance(e, EDropFront) or isinstance(e, EDropBack)) and not at_runtime:
return No("EDrop* in state position")
if not allow_big_sets.value and isinstance(e, EFlatMap) and not at_runtime:
return No("EFlatMap in state position")
if not allow_int_arithmetic_state.value and not at_runtime and isinstance(e, EBinOp) and e.type == INT:
return No("integer arithmetic in state position")
if is_collection(e.type) and not is_scalar(e.type.elem_type):
return No("collection of nonscalar: e {}\n elem_type: {}\n".format(e, e.type.elem_type))
if isinstance(e.type, TMap) and not is_scalar(e.type.k):
return No("bad key type {}".format(pprint(e.type.k)))
if isinstance(e.type, TMap) and isinstance(e.type.v, TMap):
return No("map to map")
# This check is probably a bad idea: whether `the` is legal may depend on
# the contex that the expression is embedded within, so we can't skip it
# during synthesis just because it looks invalid now.
# if isinstance(e, EUnaryOp) and e.op == UOp.The:
# len = EUnaryOp(UOp.Length, e.e).with_type(INT)
# if not valid(EImplies(assumptions, EBinOp(len, "<=", ENum(1).with_type(INT)).with_type(BOOL))):
# return No("illegal application of 'the': could have >1 elems")
if not at_runtime and isinstance(e, EBinOp) and e.op == "-" and is_collection(e.type):
return No("collection subtraction in state position")
# if not at_runtime and isinstance(e, ESingleton):
# return No("singleton in state position")
if not allow_nonzero_state_constants.value and not at_runtime and isinstance(e, ENum) and e.val != 0:
return No("nonzero integer constant in state position")
if not allow_binop_state.value and at_runtime and isinstance(e, EStateVar) and isinstance(e.e, EBinOp) and is_scalar(e.e.e1.type) and is_scalar(e.e.e2.type):
return No("constant-time binary operator {!r} in state position".format(e.e.op))
if not allow_conditional_state.value and not at_runtime and isinstance(e, ECond):
return No("conditional in state position")
if isinstance(e, EMakeMap2) and isinstance(e.e, EEmptyList):
return No("trivially empty map")
if isinstance(e, EMakeMap2) and isinstance(e.e, ESingleton):
return No("really tiny map")
if not at_runtime and (isinstance(e, EArgMin) or isinstance(e, EArgMax)):
# Cozy has no way to efficiently implement mins/maxes when more than
# one element may leave the collection.
from cozy.state_maintenance import mutate
for op in ops:
elems = e.e
elems_prime = mutate(elems, op.body)
formula = EAll([assumptions] + list(op.assumptions) + [EGt(ELen(EBinOp(elems, "-", elems_prime).with_type(elems.type)), ONE)])
if solver.satisfiable(formula):
return No("more than one element might be removed during {}".format(op.name))
if not allow_peels.value and not at_runtime and isinstance(e, EFilter):
# catch "peels": removal of zero or one elements
if solver.valid(EImplies(assumptions, ELe(ELen(EFilter(e.e, ELambda(e.predicate.arg, ENot(e.predicate.body))).with_type(e.type)), ONE))):
return No("filter is a peel")
if not allow_big_maps.value and not at_runtime and isinstance(e, EMakeMap2) and is_collection(e.type.v):
all_collections = [sv for sv in state_vars if is_collection(sv.type)]
total_size = ENum(0).with_type(INT)
for c in all_collections:
total_size = EBinOp(total_size, "+", EUnaryOp(UOp.Length, c).with_type(INT)).with_type(INT)
my_size = EUnaryOp(UOp.Length, EFlatMap(EUnaryOp(UOp.Distinct, e.e).with_type(e.e.type), e.value_function).with_type(e.type.v)).with_type(INT)
s = EImplies(
assumptions,
EBinOp(total_size, ">=", my_size).with_type(BOOL))
if not solver.valid(s):
return No("non-polynomial-sized map")
return True
def build(self, cache, size):
# print("Cache:")
# for (e, sz, pool) in cache:
# from cozy.syntax_tools import pprint
# print(" @size={}, pool={}\t:\t{}".format(sz, pool, pprint(e)))
binders_by_type = group_by(self.binders, lambda b: b.type)
for pool in ALL_POOLS:
if size == 1:
yield self.check(T, pool)
yield self.check(F, pool)
yield self.check(ZERO, pool)
yield self.check(ONE, pool)
for b in self.binders:
yield self.check(b, pool)
if pool == STATE_POOL:
for v in self.state_vars:
yield self.check(v, pool)
elif pool == RUNTIME_POOL:
for v in self.args:
yield self.check(v, pool)
if not build_exprs.value:
return
for e in cache.find(pool=STATE_POOL, size=size - 1):
if all(v in self.state_vars for v in free_vars(e)):
yield self.check(
EStateVar(e).with_type(e.type), RUNTIME_POOL)
for e in cache.find(pool=pool, size=size - 1):
t = TBag(e.type)
yield self.check(EEmptyList().with_type(t), pool)
yield self.check(ESingleton(e).with_type(t), pool)
for e in cache.find(pool=pool, type=TRecord, size=size - 1):
for (f, t) in e.type.fields:
yield self.check(EGetField(e, f).with_type(t), pool)
for e in cache.find_collections(pool=pool, size=size - 1):
if is_numeric(e.type.t):
yield self.check(
EUnaryOp(UOp.Sum, e).with_type(e.type.t), pool)
for e in cache.find(pool=pool, type=THandle, size=size - 1):
yield self.check(
EGetField(e, "val").with_type(e.type.value_type), pool)
for e in cache.find(pool=pool, type=TTuple, size=size - 1):
for n in range(len(e.type.ts)):
yield self.check(
ETupleGet(e, n).with_type(e.type.ts[n]), pool)
for e in cache.find(pool=pool, type=BOOL, size=size - 1):
yield self.check(EUnaryOp(UOp.Not, e).with_type(BOOL), pool)
for e in cache.find(pool=pool, type=INT, size=size - 1):
yield self.check(EUnaryOp("-", e).with_type(INT), pool)
for m in cache.find(pool=pool, type=TMap, size=size - 1):
yield self.check(EMapKeys(m).with_type(TBag(m.type.k)), pool)
for (sz1, sz2) in pick_to_sum(2, size - 1):
for a1 in cache.find(pool=pool, size=sz1):
if not is_numeric(a1.type):
continue
for a2 in cache.find(pool=pool, type=a1.type, size=sz2):
yield self.check(
EBinOp(a1, "+", a2).with_type(INT), pool)
yield self.check(
EBinOp(a1, "-", a2).with_type(INT), pool)
yield self.check(
EBinOp(a1, ">", a2).with_type(BOOL), pool)
yield self.check(
EBinOp(a1, "<", a2).with_type(BOOL), pool)
yield self.check(
EBinOp(a1, ">=", a2).with_type(BOOL), pool)
yield self.check(
EBinOp(a1, "<=", a2).with_type(BOOL), pool)
for a1 in cache.find_collections(pool=pool, size=sz1):
for a2 in cache.find(pool=pool, type=a1.type, size=sz2):
yield self.check(
EBinOp(a1, "+", a2).with_type(a1.type), pool)
yield self.check(
EBinOp(a1, "-", a2).with_type(a1.type), pool)
for a2 in cache.find(pool=pool, type=a1.type.t, size=sz2):
yield self.check(
EBinOp(a2, BOp.In, a1).with_type(BOOL), pool)
for a1 in cache.find(pool=pool, type=BOOL, size=sz1):
for a2 in cache.find(pool=pool, type=BOOL, size=sz2):
yield self.check(
EBinOp(a1, BOp.And, a2).with_type(BOOL), pool)
yield self.check(
EBinOp(a1, BOp.Or, a2).with_type(BOOL), pool)
for a1 in cache.find(pool=pool, size=sz1):
if not isinstance(a1.type, TMap):
for a2 in cache.find(pool=pool, type=a1.type,
size=sz2):
yield self.check(EEq(a1, a2), pool)
yield self.check(
EBinOp(a1, "!=", a2).with_type(BOOL), pool)
for m in cache.find(pool=pool, type=TMap, size=sz1):
for k in cache.find(pool=pool, type=m.type.k, size=sz2):
yield self.check(
EMapGet(m, k).with_type(m.type.v), pool)
yield self.check(EHasKey(m, k).with_type(BOOL), pool)
for (sz1, sz2, sz3) in pick_to_sum(3, size - 1):
for cond in cache.find(pool=pool, type=BOOL, size=sz1):
for then_branch in cache.find(pool=pool, size=sz2):
for else_branch in cache.find(pool=pool,
size=sz3,
type=then_branch.type):
yield self.check(
ECond(cond, then_branch,
else_branch).with_type(then_branch.type),
pool)
for bag in cache.find_collections(pool=pool, size=size - 1):
# len of bag
count = EUnaryOp(UOp.Length, bag).with_type(INT)
yield self.check(count, pool)
# empty?
yield self.check(
EUnaryOp(UOp.Empty, bag).with_type(BOOL), pool)
# exists?
yield self.check(
EUnaryOp(UOp.Exists, bag).with_type(BOOL), pool)
# singleton?
yield self.check(EEq(count, ONE), pool)
yield self.check(
EUnaryOp(UOp.The, bag).with_type(bag.type.t), pool)
yield self.check(
EUnaryOp(UOp.Distinct, bag).with_type(bag.type), pool)
yield self.check(
EUnaryOp(UOp.AreUnique, bag).with_type(BOOL), pool)
if bag.type.t == BOOL:
yield self.check(
EUnaryOp(UOp.Any, bag).with_type(BOOL), pool)
yield self.check(
EUnaryOp(UOp.All, bag).with_type(BOOL), pool)
for (sz1, sz2) in pick_to_sum(2, size - 1):
for bag in cache.find_collections(pool=pool, size=sz1):
for binder in binders_by_type[bag.type.t]:
for body in itertools.chain(
cache.find(pool=pool, size=sz2), (binder, )):
yield self.check(
EMap(bag,
ELambda(binder,
body)).with_type(TBag(body.type)),
pool)
if body.type == BOOL:
yield self.check(
EFilter(bag,
ELambda(binder,
body)).with_type(bag.type),
pool)
if body.type == INT:
yield self.check(
EArgMin(bag, ELambda(
binder, body)).with_type(bag.type.t),
pool)
yield self.check(
EArgMax(bag, ELambda(
binder, body)).with_type(bag.type.t),
pool)
if pool == RUNTIME_POOL and isinstance(
body.type, TBag):
yield self.check(
EFlatMap(bag,
ELambda(binder, body)).with_type(
TBag(body.type.t)), pool)
for (sz1, sz2) in pick_to_sum(2, size - 1):
for bag in cache.find_collections(pool=STATE_POOL, size=sz1):
if not is_scalar(bag.type.t):
continue
for b in binders_by_type[bag.type.t]:
for val in cache.find(pool=STATE_POOL, size=sz2):
t = TMap(bag.type.t, val.type)
m = EMakeMap2(bag, ELambda(b, val)).with_type(t)
yield self.check(m, STATE_POOL)
def can_serve_as_value(e, binder, state):
fvs = free_vars(e)
return binder not in fvs and not any(v == binder or v in state
for v in fvs)
def ECountIn(e, collection):
"""Count the number of times e occurs in the collection"""
from cozy.syntax_tools import free_vars, fresh_var
assert e.type == collection.type.elem_type
arg = fresh_var(e.type, omit=free_vars(e))
return EUnaryOp(UOp.Length, EFilter(collection, ELambda(arg, EEq(arg, e))).with_type(collection.type)).with_type(INT)
def build(self, cache, size):
for e in cache.find(pool=RUNTIME_POOL, size=size - 1, type=INT):
if not is_root(e):
continue
e2 = simplify_sum(e)
if e != e2:
yield self.check(e2, RUNTIME_POOL)
# for e in cache.find(pool=RUNTIME_POOL, size=size-1):
# if isinstance(e, EMapGet) and isinstance(e.map, EMakeMap2):
# x = e.map.value.apply_to(e.key)
# x._tag = True
# yield self.check(x, RUNTIME_POOL)
# [x] - ys
for e in cache.find_collections(pool=RUNTIME_POOL, size=size - 1):
if not is_root(e):
continue
if isinstance(e, EBinOp) and e.op == "-" and isinstance(
e.e1, ESingleton):
x = e.e1.e
y = e.e2
x = ECond(
EBinOp(x, BOp.In, y).with_type(BOOL),
EEmptyList().with_type(e.type), e.e1).with_type(e.type)
yield self.check(x, RUNTIME_POOL)
elif isinstance(e, EUnaryOp) and e.op == UOp.Distinct:
e = strip_EStateVar(e)
m = EMakeMap2(e.e, mk_lambda(e.type.t, lambda x: T)).with_type(
TMap(e.type.t, BOOL))
yield self.check(m, STATE_POOL)
m = EStateVar(m).with_type(m.type)
yield self.check(m, RUNTIME_POOL)
x = EMapKeys(m).with_type(e.type)
# x._tag = True
yield self.check(x, RUNTIME_POOL)
# # x in ys ----> (count x in ys) > 0
# for e in cache.find(pool=RUNTIME_POOL, type=BOOL, size=size-1):
# if isinstance(e, EBinOp) and e.op == BOp.In:
# for b in self.binders:
# if b.type != e.e1.type:
# continue
# x = EGt(
# EUnaryOp(UOp.Length, EFilter(e.e2, ELambda(b, EEq(e.e1, b))).with_type(e.e2.type)).with_type(INT),
# ZERO)
# x._tag = True
# yield self.check(x, RUNTIME_POOL)
for e in cache.find(pool=RUNTIME_POOL, size=size - 1):
if not is_root(e):
continue
if (isinstance(e, EArgMin) or isinstance(
e, EArgMax)) and isinstance(e.e, EBinOp) and e.e.op == "+":
l = e.e.e1
r = e.e.e2
op = e.e.op
f = lambda x: type(e)(x, e.f).with_type(e.type)
ll = EStateVar(f(l.e)).with_type(e.type) if isinstance(
l, EStateVar) else f(l)
rr = EStateVar(f(r.e)).with_type(e.type) if isinstance(
r, EStateVar) else f(r)
x = ECond(
EUnaryOp(UOp.Exists, l).with_type(BOOL),
ECond(
EUnaryOp(UOp.Exists, r).with_type(BOOL),
f(
EBinOp(
ESingleton(ll).with_type(e.e.type), op,
ESingleton(rr).with_type(e.e.type)).with_type(
e.e.type)), ll).with_type(e.type),
rr).with_type(e.type)
# from cozy.solver import valid
# assert valid(EEq(e, x), model_callback=print)
x._tag = True
yield self.check(x, RUNTIME_POOL)
# is-last(x, l)
for (sz1, sz2) in pick_to_sum(2, size - 1):
for e1 in cache.find(pool=RUNTIME_POOL, size=sz1):
if not is_root(e1):
continue
for e2 in cache.find_collections(pool=STATE_POOL,
size=sz2,
of=e1.type):
if not is_root(e2):
continue
for b in self.binders:
if b.type != e1.type:
continue
m = EMakeMap2(
e2,
mk_lambda(
e2.type.t, lambda x: EUnaryOp(
UOp.Length,
EFilter(
e2,
mk_lambda(e2.type.t, lambda y: EEq(
x, y))).with_type(e2.type)).
with_type(INT))).with_type(TMap(
e2.type.t, INT))
# filt = EFilter(e2, ELambda(b, EEq(e1, b))).with_type(e2.type)
# x = EEq(
# EUnaryOp(UOp.Length, filt).with_type(INT),
# ONE)
x = EGt(
EMapGet(EStateVar(m).with_type(m.type),
e1).with_type(INT), ONE)
# x._tag = True
yield self.check(x, RUNTIME_POOL)
# histogram
# for e in cache.find_collections(pool=STATE_POOL, size=size-1):
# m = EMakeMap2(e,
# mk_lambda(e.type.t, lambda x:
# EUnaryOp(UOp.Length, EFilter(e,
# mk_lambda(e.type.t, lambda y: EEq(x, y))).with_type(e.type)).with_type(INT))).with_type(TMap(e.type.t, INT))
# m._tag = True
# yield self.check(m, STATE_POOL)
# Fixup EFilter(\x -> ECond...)
for e in cache.find_collections(pool=RUNTIME_POOL, size=size - 1):
if not is_root(e):
continue
if isinstance(e, EFilter):
for (_, x, r, _) in enumerate_fragments(e.p.body):
if isinstance(x, ECond):
lhs = EFilter(
e.e,
ELambda(e.p.arg, EAll([x.cond,
r(x.then_branch)
]))).with_type(e.type)
rhs = EFilter(
e.e,
ELambda(e.p.arg,
EAll([ENot(x.cond),
r(x.else_branch)
]))).with_type(e.type)
union = EBinOp(lhs, "+", rhs).with_type(e.type)
# yield self.check(lhs.p.body, RUNTIME_POOL)
# yield self.check(rhs.p.body, RUNTIME_POOL)
yield self.check(lhs, RUNTIME_POOL)
yield self.check(rhs, RUNTIME_POOL)
yield self.check(union, RUNTIME_POOL)
# Try instantiating bound expressions
for pool in (STATE_POOL, RUNTIME_POOL):
for (sz1, sz2) in pick_to_sum(2, size - 1):
for e1 in cache.find(pool=pool, size=sz1):
if not is_root(e1):
continue
for v in free_vars(e1):
if pool == RUNTIME_POOL:
e1 = subst(
strip_EStateVar(e1), {
sv.id: EStateVar(sv).with_type(sv.type)
for sv in self.state_vars if sv != v
})
for e2 in cache.find(pool=pool, type=v.type, size=sz2):
yield self.check(subst(e1, {v.id: e2}), pool)
for (sz1, sz2) in pick_to_sum(2, size - 1):
for e in cache.find(pool=RUNTIME_POOL, size=sz1):
if not is_root(e):
continue
for x, pool in map_accelerate(e, self.state_vars, self.binders,
self.args, cache, sz2):
yield self.check(x, pool)
if isinstance(e, EFilter) and not any(v in self.binders
for v in free_vars(e)):
for x, pool in accelerate_filter(e.e, e.p, self.state_vars,
self.binders, self.args,
cache, sz2):
yield self.check(x, pool)
for bag in cache.find_collections(pool=RUNTIME_POOL, size=size - 1):
if not is_root(bag):
continue
for a in self.args:
for v in self.state_vars:
if is_collection(v.type) and v.type == a.type:
v = EStateVar(v).with_type(v.type)
cond = EBinOp(a, BOp.In, v).with_type(BOOL)
yield self.check(
EFilter(bag, mk_lambda(bag.type.t,
lambda _: cond)).with_type(
bag.type), RUNTIME_POOL)
yield self.check(
EFilter(
bag,
mk_lambda(bag.type.t,
lambda _: ENot(cond))).with_type(
bag.type), RUNTIME_POOL)
if isinstance(bag, EFilter):
if any(v not in self.state_vars for v in free_vars(bag.e)):
continue
# separate filter conds
if isinstance(bag.p.body, EBinOp) and bag.p.body.op == BOp.And:
p1 = ELambda(bag.p.arg, bag.p.body.e1)
p2 = ELambda(bag.p.arg, bag.p.body.e2)
f1 = EFilter(bag.e, p1).with_type(bag.type)
f2 = EFilter(bag.e, p2).with_type(bag.type)
f3 = EFilter(f1, p2).with_type(bag.type)
f4 = EFilter(f2, p1).with_type(bag.type)
yield self.check(f1, RUNTIME_POOL)
yield self.check(f2, RUNTIME_POOL)
yield self.check(f3, RUNTIME_POOL)
yield self.check(f4, RUNTIME_POOL)
# construct map lookups
binder = bag.p.arg
inf = infer_map_lookup(bag.p.body, binder,
set(self.state_vars))
if inf:
key_proj, key_lookup, remaining_filter = inf
bag_binder = find_one(
self.binders,
lambda b: b.type == key_proj.type and b != binder)
if bag_binder:
m = strip_EStateVar(
EMakeMap2(
EMap(bag.e,
ELambda(binder, key_proj)).with_type(
type(bag.type)(key_proj.type)),
ELambda(
bag_binder,
EFilter(
bag.e,
ELambda(binder,
EEq(key_proj,
bag_binder))).with_type(
bag.type))).with_type(
TMap(
key_proj.type,
bag.type)))
assert not any(v in self.args for v in free_vars(m))
yield self.check(m, STATE_POOL)
m = EStateVar(m).with_type(m.type)
mg = EMapGet(m, key_lookup).with_type(bag.type)
yield self.check(mg, RUNTIME_POOL)
yield self.check(
EFilter(mg, ELambda(
binder, remaining_filter)).with_type(mg.type),
RUNTIME_POOL)
# for e in cache.find(size=size-1):
# # F(xs +/- ys) ---> F(xs), F(ys)
# for z in break_plus_minus(e):
# if z != e:
# # print("broke {} --> {}".format(pprint(e), pprint(z)))
# yield z
# # try reordering operations
# for (_, e1, f) in enumerate_fragments(e):
# if e1.type == e.type and e1 != e:
# for (_, e2, g) in enumerate_fragments(e1):
# if e2.type == e.type and e2 != e1:
# # e == f(g(e2))
# yield g(f(e2))
yield from self.wrapped.build(cache, size)
def can_serve_as_key(e, binder, state):
fvs = free_vars(e)
return binder in fvs and all(v == binder or v in state for v in fvs)
def code(self) -> Spec:
"""Get the current code corresponding to this implementation.
The code is returned as a Cozy specification object, but the returned
object throws away any unused abstract state as well as all invariants
and assumptions on methods. It implements the same data structure, but
probably more efficiently.
"""
state_read_by_query = {
query_name : free_vars(query)
for query_name, query in self.query_impls.items() }
# prevent read-after-write by lifting reads before writes.
# list of SDecls
temps = defaultdict(list)
updates = dict(self.updates)
_concretization_functions = [v for v, e in self._concretization_functions]
for operator in self.op_specs:
# Compute order constraints between statements:
# v1 -> v2 means that the update code for v1 should (if possible)
# appear before the update code for v2
# (i.e. the update code for v1 reads v2)
def state_used_during_update(v1 : EVar) -> [EVar]:
v1_update_code = self.updates[(v1, operator.name)]
v1_queries = list(self.queries_used_by(v1_update_code))
res = OrderedSet()
for q in v1_queries:
res |= state_read_by_query[q]
return res
g = DirectedGraph(
nodes=_concretization_functions,
successors=state_used_during_update)
# Find the minimum set of edges we need to break cycles (see
# "feedback arc set problem")
edges_to_break = g.minimum_feedback_arc_set()
g.delete_edges(edges_to_break)
_concretization_functions = list(g.toposort())
# Lift auxiliary declarations as needed
things_updated = []
for v in _concretization_functions:
things_updated.append(v)
stm = updates[(v, operator.name)]
def problematic(e):
for x in all_exps(e):
if isinstance(x, ECall) and x.func in [q.name for q in self.query_specs]:
problems = set(things_updated) & state_read_by_query[x.func]
if problems:
return True
return False
stm = pull_temps(stm,
decls_out=temps[operator.name],
exp_is_bad=problematic)
updates[(v, operator.name)] = stm
# construct new op implementations
new_ops = []
for op in self.op_specs:
stms = [ updates[(v, op.name)] for v in _concretization_functions ]
stms.extend(hup for ((t, op_name), hup) in self.handle_updates.items() if op.name == op_name)
new_stms = seq(temps[op.name] + stms)
new_ops.append(Op(
op.name,
op.args,
[],
new_stms,
op.docstring))
# assemble final result
return Spec(
self.spec.name,
self.spec.types,
self.spec.extern_funcs,
[(v.id, e.type) for (v, e) in self._concretization_functions],
[],
list(self.query_impls.values()) + new_ops,
self.spec.header,
self.spec.footer,
self.spec.docstring)
def f(self, e):
if enforce_estatevar_wf.value:
from cozy.syntax_tools import free_vars, pprint
if not all(not v.id.startswith("_") for v in free_vars(e)):
raise IllegalStateVarBoundary(pprint(e))
old(self, e)
def cleanup(self):
"""
Remove unused state, queries, and updates.
"""
def deps(thing):
if isinstance(thing, str):
yield from free_vars(self.query_impls[thing])
elif isinstance(thing, EVar):
for op in self.op_specs:
yield self.updates[(thing, op.name)]
elif isinstance(thing, Stm):
yield from self.queries_used_by(thing)
else:
raise ValueError(repr(thing))
g = DirectedGraph(
nodes=itertools.chain(self.query_impls.keys(), (v for v, _ in self._concretization_functions), self.updates.values()),
successors=deps)
roots = [q.name for q in self.query_specs if q.visibility == Visibility.Public]
roots.extend(itertools.chain(*[self.queries_used_by(code) for ((ht, op_name), code) in self.handle_updates.items()]))
queries_to_keep = set(q for q in g.reachable_nodes(roots) if isinstance(q, str))
# remove old specs
for q in list(self.query_specs):
if q.name not in queries_to_keep:
self.query_specs.remove(q)
# remove old implementations
for qname in list(self.query_impls.keys()):
if qname not in queries_to_keep:
del self.query_impls[qname]
# remove old state vars
self._concretization_functions = [ v for v in self._concretization_functions if any(v[0] in free_vars(q) for q in self.query_impls.values()) ]
# remove old method implementations
for k in list(self.updates.keys()):
v, op_name = k
if v not in [var for (var, exp) in self._concretization_functions]:
del self.updates[k]
def _try_optimize(e : Exp, context : Context, pool : Pool):
if not accelerate.value:
return
if pool != RUNTIME_POOL:
return
state_vars = [v for v, p in context.vars() if p == STATE_POOL]
args = [v for v, p in context.vars() if p == RUNTIME_POOL]
# ---------------------------------------------------------------------
# "Rewrite schemes": these trigger on many different AST shapes
# They are listed first because they are more powerful than the
# specific rewrite rules below.
if not free_vars(e) and not free_funcs(e):
try:
yield _check(uneval(e.type, eval(e, {})), context, RUNTIME_POOL)
except NotImplementedError:
print("Unable to evaluate {!r}".format(e))
if all(v in state_vars for v in free_vars(e)):
nsv = strip_EStateVar(e)
sv = EStateVar(nsv).with_type(e.type)
yield _check(sv, context, RUNTIME_POOL)
for ee in fold_into_map(e, context):
yield _check(ee, context, pool)
# ---------------------------------------------------------------------
# "Rewrites": these trigger on specific AST nodes
if isinstance(e, EBinOp):
if e.op == "-" and is_collection(e.type):
ee = optimized_bag_difference(e.e1, e.e2)
yield _check(ee, context, RUNTIME_POOL)
if e.op == "===" and isinstance(e.e1.type, THandle):
yield _check(EAll([
optimized_eq(optimized_addr(e.e1), optimized_addr(e.e2)),
optimized_eq(optimized_val(e.e1), optimized_val(e.e2)).with_type(BOOL)]), context, RUNTIME_POOL)
if e.op == BOp.In:
ee = optimized_in(e.e1, e.e2)
yield _check(ee, context, RUNTIME_POOL)
if isinstance(e, ECond):
yield _check(optimized_cond(e.cond, e.then_branch, e.else_branch), context, RUNTIME_POOL)
if isinstance(e, EGetField):
for ee in optimized_get_field(e.e, e.field_name, args):
yield _check(ee, context, RUNTIME_POOL)
if isinstance(e, EListGet) and e.index == ZERO:
for res in optimized_the(e.e, args):
yield _check(res, context, RUNTIME_POOL)
if isinstance(e, EListGet) and isinstance(e.e, ECond):
yield optimized_cond(e.e.cond,
EListGet(e.e.then_branch, e.index).with_type(e.type),
EListGet(e.e.else_branch, e.index).with_type(e.type))
from cozy.structures.treemultiset import ETreeMultisetElems, ETreeMultisetPeek
if isinstance(e, EListGet) and isinstance(e.e, ETreeMultisetElems):
yield ETreeMultisetPeek(e.e.e, e.index).with_type(e.type)
if isinstance(e, EMapGet):
ee = inline_mapget(e, context)
yield _check(ee, context, RUNTIME_POOL)
if isinstance(e, EUnaryOp):
if e.op == UOp.Sum:
for ee in optimized_sum(e.e, args):
yield _check(ee, context, RUNTIME_POOL)
if e.op == UOp.Length:
ee = optimized_len(e.e)
yield _check(ee, context, RUNTIME_POOL)
if e.op == UOp.Empty:
ee = optimized_empty(e.e)
yield _check(ee, context, RUNTIME_POOL)
if e.op == UOp.Exists:
ee = optimized_exists(e.e)
yield _check(ee, context, RUNTIME_POOL)
if e.op == UOp.Distinct:
for ee in optimized_distinct(e.e, args):
yield _check(ee, context, RUNTIME_POOL)
if e.op == UOp.The:
for ee in optimized_the(e.e, args):
yield _check(ee, context, RUNTIME_POOL)
if isinstance(e, EArgMin) or isinstance(e, EArgMax):
for ee in optimized_best(e.e, e.key_function, "<" if isinstance(e, EArgMin) else ">", args=args):
yield _check(ee, context, RUNTIME_POOL)
if isinstance(e, EFilter):
for ee in optimized_filter(e.e, e.predicate, args=args):
yield _check(ee, context, RUNTIME_POOL)
if isinstance(e, EMap):
for ee in optimized_map(e.e, e.transform_function, args=args):
yield _check(ee, context, RUNTIME_POOL)
from cozy.syntax import ESorted
from cozy.structures.treemultiset import EMakeMaxTreeMultiset, TMaxTreeMultiset, EMakeMinTreeMultiset, TMinTreeMultiset, ETreeMultisetElems
target = e
if isinstance(target, ESorted) and isinstance(target.e, EStateVar):
e_max = EMakeMaxTreeMultiset(target.e.e).with_type(TMaxTreeMultiset(target.e.e.type.elem_type))
e_min = EMakeMinTreeMultiset(target.e.e).with_type(TMinTreeMultiset(target.e.e.type.elem_type))
ee = optimized_cond(target.asc,
ETreeMultisetElems(EStateVar(e_min).with_type(e_min.type)).with_type(target.type),
ETreeMultisetElems(EStateVar(e_max).with_type(e_max.type)).with_type(target.type))
yield _check(ee, context, RUNTIME_POOL)
def free_vars_and_funcs(e):
for v in free_vars(e):
yield v.id
for f in free_funcs(e):
yield f
def _simple_filter(xs : Exp, p : ELambda, args : {EVar}):
"""Assumes the body of p is already in negation normal form"""
if p.body == ETRUE:
yield xs
return
if p.body == EFALSE:
yield EEmptyList().with_type(xs.type)
return
if isinstance(xs, EEmptyList):
yield xs
return
yielded = False
if isinstance(xs, ESingleton):
yielded = True
yield optimized_cond(p.apply_to(xs.e), xs, EEmptyList().with_type(xs.type))
if isinstance(p.body, EBinOp) and p.body.op == BOp.Or:
for e1, e2 in itertools.permutations([p.body.e1, p.body.e2]):
for r1 in _simple_filter(xs, ELambda(p.arg, e1), args):
for r2 in _simple_filter(xs, ELambda(p.arg, EAll([e2, ENot(e1)])), args):
yielded = True
yield EBinOp(r1, "+", r2).with_type(xs.type)
if isinstance(p.body, EBinOp) and p.body.op == BOp.And:
for e1, e2 in itertools.permutations([p.body.e1, p.body.e2]):
for r1 in _simple_filter(xs, ELambda(p.arg, e1), args):
yielded = True
yield from _simple_filter(r1, ELambda(p.arg, e2), args)
if isinstance(xs, EStateVar) and not any(v in args for v in free_vars(p)):
yielded = True
yield EStateVar(EFilter(xs.e, strip_EStateVar(p)).with_type(xs.type)).with_type(xs.type)
if isinstance(xs, EMapGet) and isinstance(xs.map, EStateVar) and not any(v in args for v in free_vars(p)):
for m in map_values_multi(xs.map.e, lambda ys: _simple_filter(ys, p, args)):
yielded = True
yield EMapGet(EStateVar(m).with_type(m.type), xs.key).with_type(xs.type)
if isinstance(xs, EBinOp) and xs.op in ("+", "-"):
for e1 in _simple_filter(xs.e1, p, args):
for e2 in _simple_filter(xs.e2, p, args):
yielded = True
yield EBinOp(e1, xs.op, e2).with_type(xs.type)
if isinstance(p.body, EBinOp) and p.body.op == "==":
e1 = p.body.e1
e2 = p.body.e2
fvs2 = free_vars(e2)
fvs1 = free_vars(e1)
for (e1, fvs1), (e2, fvs2) in itertools.permutations([(e1, fvs1), (e2, fvs2)]):
if p.arg in fvs1 and not any(a in fvs1 for a in args) and p.arg not in fvs2 and isinstance(xs, EStateVar):
if e1 == p.arg:
yield optimized_cond(
optimized_in(e2, xs),
ESingleton(e2).with_type(xs.type),
EEmptyList().with_type(xs.type))
k = fresh_var(e1.type)
e = EMapGet(
EStateVar(
EMakeMap2(
EMap(xs.e, ELambda(p.arg, e1)),
ELambda(k, EFilter(xs.e, ELambda(p.arg, EEq(e1, k)))))),
e2)
res = retypecheck(e)
assert res
yielded = True
yield e
if not yielded:
yield EFilter(xs, p).with_type(xs.type)
def visit_Spec(self, spec, state_exps, sharing, abstract_state=()):
self.state_exps = state_exps
self.funcs = { f.name: f for f in spec.extern_funcs }
self.queries = { q.name: q for q in spec.methods if isinstance(q, Query) }
self.vars = set(e.id for e in all_exps(spec) if isinstance(e, EVar))
self.setup_types(spec, state_exps, sharing)
if guava.value:
self.write("import com.google.common.collect.TreeMultiset;\n")
self.write("import com.google.common.collect.Iterators;\n")
if spec.header:
self.write(spec.header.strip() + "\n\n")
if spec.docstring:
self.write(spec.docstring + "\n")
self.write("public class {} implements java.io.Serializable ".format(spec.name))
with self.block():
for name, t in spec.types:
self.types[t] = name
# member variables
for name, t in spec.statevars:
self.write("{}protected {};\n".format(INDENT, self.visit(t, name)))
# constructor
self.write(
"{indent}public {name}() {{\n{indent2}clear();\n{indent}}}\n\n"
.format(indent=INDENT, indent2=INDENT+INDENT, name=spec.name))
# explicit constructor
if abstract_state:
self.begin_statement()
self.write("public ", spec.name, "(")
self.visit_args(abstract_state)
self.write(") ")
with self.block():
for name, t in spec.statevars:
initial_value = state_exps[name]
self.visit(simplify_and_optimize(SAssign(EVar(name).with_type(t), initial_value)))
self.end_statement()
# clear
self.begin_statement()
self.write("public void clear() ")
with self.block():
for name, t in spec.statevars:
initial_value = state_exps[name]
fvs = free_vars(initial_value)
initial_value = subst(initial_value,
{v.id : evaluation.construct_value(v.type) for v in fvs})
setup = simplify_and_optimize(SAssign(EVar(name).with_type(t), initial_value))
self.visit(setup)
self.end_statement()
# methods
for op in spec.methods:
self.visit(op)
# generate auxiliary types
for t, name in self.types.items():
self.define_type(spec.name, t, name, sharing)
self.write("\n")
self.write(spec.footer)
if not spec.footer.endswith("\n"):
self.write("\n")
def pull_temps(s : Stm, decls_out : [SDecl], exp_is_bad) -> Stm:
"""Remove "bad" expressions from `s`.
This procedure returns a statement new_s that replaces every expression in
`s` where `exp_is_bad` returns True with a fresh variable. After running,
`decls_out` contains definitions for the fresh variables so that the whole
statement
decls_out; new_s
should return the same result as `s`.
"""
def pull(e : Exp) -> Exp:
"""Pull an expression into a temporary.
Creates a fresh variable for `e`, writes a declaration into `decls_out`,
and returns the fresh variable.
"""
if exp_is_bad(e):
v = fresh_var(e.type)
decls_out.append(SDecl(v, e))
return v
return e
if isinstance(s, SNoOp):
return s
if isinstance(s, SSeq):
s1 = pull_temps(s.s1, decls_out, exp_is_bad)
s2 = pull_temps(s.s2, decls_out, exp_is_bad)
return SSeq(s1, s2)
if isinstance(s, SDecl):
return SDecl(s.var, pull(s.val))
if isinstance(s, SIf):
cond = pull(s.cond)
s1 = pull_temps(s.then_branch, decls_out, exp_is_bad)
s2 = pull_temps(s.else_branch, decls_out, exp_is_bad)
return SIf(cond, s1, s2)
if isinstance(s, SForEach):
bag = pull(s.iter)
d_tmp = []
body = pull_temps(s.body, d_tmp, exp_is_bad)
to_fix, ok = partition(d_tmp, lambda d: s.loop_var in free_vars(d.val))
decls_out.extend(ok)
for d in to_fix:
v = d.var
mt = TMap(s.loop_var.type, v.type)
m = EMakeMap2(bag, ELambda(s.loop_var, d.val)).with_type(mt)
mv = fresh_var(m.type)
md = SDecl(mv, m)
decls_out.append(md)
body = subst(body, { v.id : EMapGet(mv, s.loop_var).with_type(v.type) })
return SForEach(s.loop_var, bag, body)
if isinstance(s, SAssign):
return SAssign(s.lhs, pull(s.rhs))
if isinstance(s, SCall):
return SCall(s.target, s.func, tuple(pull(arg) for arg in s.args))
if isinstance(s, SMapDel):
return SMapDel(s.map, pull(s.key))
if isinstance(s, SMapPut):
return SMapPut(s.map, pull(s.key), pull(s.value))
if isinstance(s, SMapUpdate):
key = pull(s.key)
d_tmp = []
change = pull_temps(s.change, d_tmp, exp_is_bad)
for d in d_tmp:
if s.val_var in free_vars(d.val):
decls_out.append(SDecl(d.var, subst(d.val, { s.val_var.id : EMapGet(s.map, key).with_type(s.val_var.type) })))
else:
decls_out.append(d)
return SMapUpdate(s.map, key, s.val_var, change)
raise NotImplementedError(s)
def EDeepIn(e1, e2):
from cozy.syntax_tools import free_vars, fresh_var
arg = fresh_var(e1.type, omit=free_vars(e1))
return EUnaryOp(UOp.Any,
EMap(e2, ELambda(arg,
EDeepEq(arg, e1))).with_type(BOOL_BAG)).with_type(BOOL)