diff --git a/src/subtype.c b/src/subtype.c index e623fc3577c6d..5edcd100ee8e0 100644 --- a/src/subtype.c +++ b/src/subtype.c @@ -1565,37 +1565,12 @@ static int is_definite_length_tuple_type(jl_value_t *x) return k == JL_VARARG_NONE || k == JL_VARARG_INT; } -static int _forall_exists_subtype(jl_value_t *x, jl_value_t *y, jl_stenv_t *e, int param, int *count, int *noRmore); - -static int may_contain_union_decision(jl_value_t *x, jl_stenv_t *e, jl_typeenv_t *log) JL_NOTSAFEPOINT +static int is_exists_typevar(jl_value_t *x, jl_stenv_t *e) { - if (x == NULL || x == (jl_value_t*)jl_any_type || x == jl_bottom_type) - return 0; - if (jl_is_unionall(x)) - return may_contain_union_decision(((jl_unionall_t *)x)->body, e, log); - if (jl_is_datatype(x)) { - jl_datatype_t *xd = (jl_datatype_t *)x; - for (int i = 0; i < jl_nparams(xd); i++) { - jl_value_t *param = jl_tparam(xd, i); - if (jl_is_vararg(param)) - param = jl_unwrap_vararg(param); - if (may_contain_union_decision(param, e, log)) - return 1; - } - return 0; - } if (!jl_is_typevar(x)) - return jl_is_type(x); - jl_typeenv_t *t = log; - while (t != NULL) { - if (x == (jl_value_t *)t->var) - return 1; - t = t->prev; - } - jl_typeenv_t newlog = { (jl_tvar_t*)x, NULL, log }; - jl_varbinding_t *xb = lookup(e, (jl_tvar_t *)x); - return may_contain_union_decision(xb ? xb->lb : ((jl_tvar_t *)x)->lb, e, &newlog) || - may_contain_union_decision(xb ? xb->ub : ((jl_tvar_t *)x)->ub, e, &newlog); + return 0; + jl_varbinding_t *vb = lookup(e, (jl_tvar_t *)x); + return vb && vb->right; } static int has_exists_typevar(jl_value_t *x, jl_stenv_t *e) JL_NOTSAFEPOINT @@ -1626,31 +1601,9 @@ static int local_forall_exists_subtype(jl_value_t *x, jl_value_t *y, jl_stenv_t int kindy = !jl_has_free_typevars(y); if (kindx && kindy) return jl_subtype(x, y); - if (may_contain_union_decision(y, e, NULL) && pick_union_decision(e, 1) == 0) { - jl_saved_unionstate_t oldRunions; push_unionstate(&oldRunions, &e->Runions); - e->Lunions.used = e->Runions.used = 0; - e->Lunions.depth = e->Runions.depth = 0; - e->Lunions.more = e->Runions.more = 0; - int count = 0, noRmore = 0; - sub = _forall_exists_subtype(x, y, e, param, &count, &noRmore); - pop_unionstate(&e->Runions, &oldRunions); - // We could skip the slow path safely if - // 1) `_∀_∃_subtype` has tested all cases - // 2) `_∀_∃_subtype` returns 1 && `x` and `y` contain no ∃ typevar - // Once `limit_slow == 1`, also skip it if - // 1) `_∀_∃_subtype` returns 0 - // 2) the left `Union` looks big - // TODO: `limit_slow` ignores complexity from inner `local_∀_exists_subtype`. - if (limit_slow == -1) - limit_slow = kindx || kindy; - int skip = noRmore || (limit_slow && (count > 3 || !sub)) || - (sub && (kindx || !has_exists_typevar(x, e)) && - (kindy || !has_exists_typevar(y, e))); - if (skip) - e->Runions.more = oldRmore; - } - else { - // slow path + int has_exists = (!kindx && has_exists_typevar(x, e)) || + (!kindy && has_exists_typevar(y, e)); + if (has_exists && (is_exists_typevar(x, e) != is_exists_typevar(y, e))) { e->Lunions.used = 0; while (1) { e->Lunions.more = 0; @@ -1659,7 +1612,51 @@ static int local_forall_exists_subtype(jl_value_t *x, jl_value_t *y, jl_stenv_t if (!sub || !next_union_state(e, 0)) break; } + return sub; } + if (limit_slow == -1) + limit_slow = kindx || kindy; + jl_savedenv_t se; + save_env(e, &se, has_exists); + int count, limited = 0, ini_count = 0; + jl_saved_unionstate_t latestLunions = {0, 0, 0, NULL}; + while (1) { + count = ini_count; + if (ini_count == 0) + e->Lunions.used = 0; + else + pop_unionstate(&e->Lunions, &latestLunions); + while (1) { + e->Lunions.more = 0; + e->Lunions.depth = 0; + if (count < 4) count++; + sub = subtype(x, y, e, param); + if (limit_slow && count == 4) + limited = 1; + if (!sub || !next_union_state(e, 0)) + break; + if (limited || !has_exists || e->Runions.more == oldRmore) { + // re-save env and freeze the ∃decision for previous ∀Union + // Note: We could ignore the rest `∃Union` decisions if `x` and `y` + // contain no ∃ typevar, as they have no effect on env. + ini_count = count; + push_unionstate(&latestLunions, &e->Lunions); + re_save_env(e, &se, has_exists); + e->Runions.more = oldRmore; + } + } + if (sub || e->Runions.more == oldRmore) + break; + assert(e->Runions.more > oldRmore); + next_union_state(e, 1); + restore_env(e, &se, has_exists); // also restore Rdepth here + e->Runions.more = oldRmore; + } + if (!sub) + assert(e->Runions.more == oldRmore); + else if (limited || !has_exists) + e->Runions.more = oldRmore; + free_env(&se); return sub; } @@ -1729,7 +1726,7 @@ static int exists_subtype(jl_value_t *x, jl_value_t *y, jl_stenv_t *e, jl_savede } } -static int _forall_exists_subtype(jl_value_t *x, jl_value_t *y, jl_stenv_t *e, int param, int *count, int *noRmore) +static int forall_exists_subtype(jl_value_t *x, jl_value_t *y, jl_stenv_t *e, int param) { // The depth recursion has the following shape, after simplification: // ∀₁ @@ -1741,12 +1738,8 @@ static int _forall_exists_subtype(jl_value_t *x, jl_value_t *y, jl_stenv_t *e, i e->Lunions.used = 0; int sub; - if (count) *count = 0; - if (noRmore) *noRmore = 1; while (1) { sub = exists_subtype(x, y, e, &se, param); - if (count) *count = (*count < 4) ? *count + 1 : 4; - if (noRmore) *noRmore = *noRmore && e->Runions.more == 0; if (!sub || !next_union_state(e, 0)) break; re_save_env(e, &se, 1); @@ -1756,11 +1749,6 @@ static int _forall_exists_subtype(jl_value_t *x, jl_value_t *y, jl_stenv_t *e, i return sub; } -static int forall_exists_subtype(jl_value_t *x, jl_value_t *y, jl_stenv_t *e, int param) -{ - return _forall_exists_subtype(x, y, e, param, NULL, NULL); -} - static void init_stenv(jl_stenv_t *e, jl_value_t **env, int envsz) { e->vars = NULL;