From 0916c5c6e536affca1f6f0c7693d68fb64843c1c Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Micha=C5=82=20Muska=C5=82a?= Date: Tue, 17 Jul 2018 18:38:10 +0200 Subject: maps:new/0 is no longer a BIF Implementing it in Erlang allows taking advantage of the literal pool optimisation, this means the function implemented in Erlang does no allocations, while the BIF had to allocate new map each time it was called. Benchmarks show the function is also slightly faster now. --- erts/emulator/beam/bif.tab | 1 - erts/emulator/beam/erl_map.c | 19 ------------------- 2 files changed, 20 deletions(-) (limited to 'erts/emulator/beam') diff --git a/erts/emulator/beam/bif.tab b/erts/emulator/beam/bif.tab index 7548924178..a770524221 100644 --- a/erts/emulator/beam/bif.tab +++ b/erts/emulator/beam/bif.tab @@ -629,7 +629,6 @@ bif maps:from_list/1 bif maps:is_key/2 bif maps:keys/1 bif maps:merge/2 -bif maps:new/0 bif maps:put/3 bif maps:remove/2 bif maps:update/3 diff --git a/erts/emulator/beam/erl_map.c b/erts/emulator/beam/erl_map.c index cba17d3e6a..4a1fe4470e 100644 --- a/erts/emulator/beam/erl_map.c +++ b/erts/emulator/beam/erl_map.c @@ -1505,25 +1505,6 @@ int hashmap_key_hash_cmp(Eterm* ap, Eterm* bp) return ap ? -1 : 1; } -/* maps:new/0 */ - -BIF_RETTYPE maps_new_0(BIF_ALIST_0) { - Eterm* hp; - Eterm tup; - flatmap_t *mp; - - hp = HAlloc(BIF_P, (MAP_HEADER_FLATMAP_SZ + 1)); - tup = make_tuple(hp); - *hp++ = make_arityval(0); - - mp = (flatmap_t*)hp; - mp->thing_word = MAP_HEADER_FLATMAP; - mp->size = 0; - mp->keys = tup; - - BIF_RET(make_flatmap(mp)); -} - /* maps:put/3 */ BIF_RETTYPE maps_put_3(BIF_ALIST_3) { -- cgit v1.2.3