Optimize hash operation with unsafe car/cdr.

The associative lists that make up the chains of a hash table
are guaranteed to be made of conses. We can use unsafe
versions of car, cdr, rplaca and rplacd to speed up hash
operations.

* eval.c (op_dohash): Use unsafe operations on hash cell.

* filter.c (trie_compress, regex_from_trie): Likewise.

* hash.c (hash_equal_op, hash_print_op, hash_mark, hash_grow,
hash_assoc, hash_assql, copy_hash_chain, gethash, inhash,
gethash_n, sethash, remhash, hash_next, maphash,
do_weak_tables, group_by, group_reduce, hash_keys_lazy,
hash_keys, hash_values_lazy, hash_values, hash_pairs_lazy,
hash_pairs, hash_alist_lazy, hash_uni, hash_diff,
hash_symdiff, hash_isec, hash_subset, hash_update,
hash_update_1, hash_revget): Likewise.

* lib.c (us_rplaca, us_rplacd): New functions.
(package_local_symbols, package_foreign_symbols, where,
populate_obj_hash, obj_hash_merge): Use unsafe operations on
hash cell

* lib.h (us_rplaca, us_rplacd): Declared.

* parser.c (circ_backpatch, get_visible_syms): Use unsafe
operations on hash cell.

* struct.c (method_name, get_slot_syms): Likewise.

1 files changed, 3 insertions, 3 deletions

diff --git a/struct.c b/struct.c
index d2407ace..9fa3b4f7 100644
--- a/struct.c
+++ b/struct.c
@@ -1550,8 +1550,8 @@ val method_name(val fun)
   val sth_cell;
 
   while ((sth_cell = hash_next(sth_iter))) {
-    val sym = car(sth_cell);
-    val stype = cdr(sth_cell);
+    val sym = us_car(sth_cell);
+    val stype = us_cdr(sth_cell);
     val sl_iter;
     struct struct_type *st = coerce(struct struct_type *, stype->co.handle);
 
@@ -1596,7 +1596,7 @@ val get_slot_syms(val package, val is_current, val method_only)
   val sth_cell;
 
   while ((sth_cell = hash_next(sth_iter))) {
-    val stype = cdr(sth_cell);
+    val stype = us_cdr(sth_cell);
     val sl_iter;
     struct struct_type *st = coerce(struct struct_type *, stype->co.handle);