From f7b4b05012a9e40deca1bdc72b02638d0be5a386 Mon Sep 17 00:00:00 2001 From: Kaz Kylheku Date: Thu, 4 Jun 2020 19:46:43 -0700 Subject: seq_iter: null list object if rewind not needed. * lib.c (seq_iter_init_with_info): Take new Boolean argument indicating whether the iterator needs to support the rewind operation. If this is false, and the object is a list, then we clobber the object, in order to eliminate the GC root. (seq_iter_init, iter_begin, iter_reset): Pass 0 for the new Boolean parameter. (seq_iter_init_with_rewind): New function. (diff, isec): Use seq_iter_init_with_rewind to request an iterator with rewind support for the second sequence. --- lib.c | 20 ++++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-) diff --git a/lib.c b/lib.c index c30ed343..8ba048f3 100644 --- a/lib.c +++ b/lib.c @@ -503,7 +503,8 @@ void seq_iter_rewind(seq_iter_t *it) } static void seq_iter_init_with_info(val self, seq_iter_t *it, - val obj, seq_info_t si) + val obj, seq_info_t si, + int support_rewind) { it->inf = si; @@ -519,6 +520,8 @@ static void seq_iter_init_with_info(val self, seq_iter_t *it, it->ul.len = 0; it->get = seq_iter_get_list; it->peek = seq_iter_peek_list; + if (!support_rewind) + it->inf.obj = nil; break; case SEQ_VECLIKE: it->ui.index = 0; @@ -587,7 +590,12 @@ static void seq_iter_init_with_info(val self, seq_iter_t *it, void seq_iter_init(val self, seq_iter_t *it, val obj) { - seq_iter_init_with_info(self, it, obj, seq_info(obj)); + seq_iter_init_with_info(self, it, obj, seq_info(obj), 0); +} + +static void seq_iter_init_with_rewind(val self, seq_iter_t *it, val obj) +{ + seq_iter_init_with_info(self, it, obj, seq_info(obj), 1); } val seq_getpos(val self, seq_iter_t *it) @@ -689,7 +697,7 @@ val iter_begin(val obj) struct seq_iter *si = coerce(struct seq_iter *, chk_calloc(1, sizeof *si)); si_obj = cobj(coerce(mem_t *, si), seq_iter_s, &seq_iter_ops); - seq_iter_init_with_info(self, si, obj, sinf); + seq_iter_init_with_info(self, si, obj, sinf, 0); return si_obj; } } @@ -783,7 +791,7 @@ val iter_reset(val iter, val obj) if (iter->co.cls == seq_iter_s) { struct seq_iter *si = coerce(struct seq_iter *, iter->co.handle); - seq_iter_init_with_info(self, si, obj, sinf); + seq_iter_init_with_info(self, si, obj, sinf, 0); return iter; } /* fallthrough */ @@ -10551,7 +10559,7 @@ val diff(val seq1, val seq2, val testfun, val keyfun) keyfun = default_arg(keyfun, identity_f); seq_iter_init(self, &si1, seq1); - seq_iter_init(self, &si2, seq2); + seq_iter_init_with_rewind(self, &si2, seq2); while (seq_get(&si1, &el1)) { val el1_key = funcall1(keyfun, el1); @@ -10658,7 +10666,7 @@ val isec(val seq1, val seq2, val testfun, val keyfun) keyfun = default_arg(keyfun, identity_f); seq_iter_init(self, &si1, seq1); - seq_iter_init(self, &si2, seq2); + seq_iter_init_with_rewind(self, &si2, seq2); while (seq_get(&si1, &el1)) { val el1_key = funcall1(keyfun, el1); -- cgit v1.2.3