michael/lean2
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

perf(kernel/metavar): performance problem with occurs method

Browse source 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
This commit is contained in:
Leonardo de Moura 2014-07-23 10:35:27 -07:00
parent 61661478ad
commit 301c395e59
5 changed files with 13 additions and 12 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

8
src/kernel/metavar.cpp
View file

@ -186,18 +186,16 @@ expr substitution::instantiate_metavars_wo_jst(expr const & e) {
return instantiate_metavars_fn(*this, false)(e);
}
bool substitution::occurs_expr(name const & m, expr const & e) const {
bool substitution::occurs_expr(name const & m, expr const & e) {
if (!has_expr_metavar(e))
return false;
expr new_e = instantiate(e);
bool found = false;
for_each(e, [&](expr const & e, unsigned) {
for_each(new_e, [&](expr const & e, unsigned) {
if (found || !has_expr_metavar(e)) return false;
if (is_metavar(e)) {
if (mlocal_name(e) == m)
found = true;
auto s = get_expr(e);
if (s && occurs_expr(m, *s))
found = true;
return false; // do not visit type
}
if (is_local(e)) return false; // do not visit type

4
src/kernel/metavar.h
View file

@ -78,7 +78,7 @@ public:
expr instantiate(expr const & e) { return instantiate_metavars_wo_jst(e); }
/** \brief Return true iff the metavariable \c m occurrs (directly or indirectly) in \c e. */
bool occurs_expr(name const & m, expr const & e) const;
bool occurs(expr const & m, expr const & e) const { lean_assert(is_metavar(m)); return occurs_expr(mlocal_name(m), e); }
bool occurs_expr(name const & m, expr const & e);
bool occurs(expr const & m, expr const & e) { lean_assert(is_metavar(m)); return occurs_expr(mlocal_name(m), e); }
};
}

2
src/library/unifier.cpp
View file

@ -70,7 +70,7 @@ bool context_check(expr const & e, buffer<expr> const & locals) {
// constants are in \c e are in \c locals.
// - l_false if \c e contains \c m or it contains a local constant \c l
// not in locals that is not in a metavariable application.
lbool occurs_context_check(substitution const & s, expr const & e, expr const & m, buffer<expr> const & locals) {
lbool occurs_context_check(substitution & s, expr const & e, expr const & m, buffer<expr> const & locals) {
expr root = e;
lbool r = l_true;
for_each(e, [&](expr const & e, unsigned) {

7
src/tests/kernel/metavar.cpp
View file

@ -91,11 +91,14 @@ static void tst2() {
expr f = Const("f");
expr g = Const("g");
expr a = Const("a");
lean_assert(s.occurs(m1, f(m1)));
lean_assert(!s.occurs(m2, f(m1)));
s.assign(m1, f(m2), mk_assumption_justification(1));
lean_assert(s.occurs(m2, f(m1)));
s.assign(m2, g(a), mk_assumption_justification(2));
lean_assert(check_assumptions(s.get_assignment(m1)->second, {1}));
lean_assert(s.occurs(m1, f(m1)));
lean_assert(s.occurs(m2, f(m1)));
lean_assert(!s.occurs(m1, f(m1)));
lean_assert(!s.occurs(m2, f(m1)));
lean_assert(!s.occurs(m1, f(m2)));
lean_assert(!s.occurs(m1, f(a)));
lean_assert(!s.occurs(m3, f(m1)));

4
tests/lua/subst1.lua
View file

@ -24,8 +24,8 @@ assert(s:get_expr("m") == a)
local m2 = mk_metavar("m2", Prop)
s:assign(m2, f(m))
print(s:get_expr("m2"))
assert(s:occurs(m, f(m2)))
assert(s:occurs_expr("m", f(m2)))
assert(not s:occurs(m, f(m2)))
assert(not s:occurs_expr("m", f(m2)))
print(s:get_level("u"))
print(s:instantiate(mk_sort(u)))
assert(s:instantiate(mk_sort(u)) == mk_sort(l))