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/parser.c b/parser.c
index 1478aeaf..d0c4b7a9 100644
--- a/parser.c
+++ b/parser.c
@@ -339,7 +339,7 @@ tail:
 
         while (pairs) {
           val cell = pop(&pairs);
-          sethash(obj, car(cell), cdr(cell));
+          sethash(obj, us_car(cell), us_cdr(cell));
         }
       }
     } else if (structp(obj)) {
@@ -743,9 +743,9 @@ static val get_visible_syms(val package, int include_fallback)
       val fcell;
       val new_p;
       while ((fcell = hash_next(hiter))) {
-        loc pcdr = gethash_l(lit("listener"), symhash, car(fcell), mkcloc(new_p));
+        loc pcdr = gethash_l(lit("listener"), symhash, us_car(fcell), mkcloc(new_p));
         if (new_p)
-          set(pcdr, cdr(fcell));
+          set(pcdr, us_cdr(fcell));
       }
     }
     return hash_values(symhash);