From 654a34e72e28bfa52f26ed0be3bef63dfb50bba6 Mon Sep 17 00:00:00 2001 From: Keith Packard Date: Thu, 10 Nov 2016 23:29:21 -0800 Subject: altos/lisp: Deal with memory compation in the middle of operations Handle memory compaction in places where we've got pointers into the heap across an allocation operation. Either re-compute the values from managed global references or add new roots across the allocation. Signed-off-by: Keith Packard --- src/lisp/ao_lisp_frame.c | 28 ++++++++++++++++++++-------- 1 file changed, 20 insertions(+), 8 deletions(-) (limited to 'src/lisp/ao_lisp_frame.c') diff --git a/src/lisp/ao_lisp_frame.c b/src/lisp/ao_lisp_frame.c index 7978f20a..90344719 100644 --- a/src/lisp/ao_lisp_frame.c +++ b/src/lisp/ao_lisp_frame.c @@ -174,8 +174,9 @@ ao_lisp_frame_new(int num) } static struct ao_lisp_frame * -ao_lisp_frame_realloc(struct ao_lisp_frame *frame, int new_num) +ao_lisp_frame_realloc(struct ao_lisp_frame **frame_ref, int new_num) { + struct ao_lisp_frame *frame = *frame_ref; struct ao_lisp_frame *new; int copy; @@ -184,34 +185,45 @@ ao_lisp_frame_realloc(struct ao_lisp_frame *frame, int new_num) new = ao_lisp_frame_new(new_num); if (!new) return NULL; + /* + * Re-fetch the frame as it may have moved + * during the allocation + */ + frame = *frame_ref; copy = new_num; if (copy > frame->num) copy = frame->num; memcpy(new->vals, frame->vals, copy * sizeof (struct ao_lisp_val)); - if (frame) - new->next = frame->next; + new->next = frame->next; return new; } -struct ao_lisp_frame * -ao_lisp_frame_add(struct ao_lisp_frame *frame, ao_poly atom, ao_poly val) +int +ao_lisp_frame_add(struct ao_lisp_frame **frame_ref, ao_poly atom, ao_poly val) { + struct ao_lisp_frame *frame = *frame_ref; ao_poly *ref = frame ? ao_lisp_frame_ref(frame, atom) : NULL; + if (!ref) { int f; + ao_lisp_root_poly_add(&atom); + ao_lisp_root_poly_add(&val); if (frame) { f = frame->num; - frame = ao_lisp_frame_realloc(frame, f + 1); + frame = ao_lisp_frame_realloc(frame_ref, f + 1); } else { f = 0; frame = ao_lisp_frame_new(1); } + ao_lisp_root_clear(&atom); + ao_lisp_root_clear(&val); if (!frame) - return NULL; + return 0; + *frame_ref = frame; DBG ("add atom %s %d, val %d at %d\n", ao_lisp_poly_atom(atom)->name, OFFSET(atom), OFFSET(val), f); frame->vals[f].atom = atom; ref = &frame->vals[f].val; } *ref = val; - return frame; + return 1; } -- cgit v1.2.3