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| author | Michał Muskała <[email protected]> | 2018-07-17 18:38:10 +0200 |
|---|---|---|
| committer | Michał Muskała <[email protected]> | 2018-07-17 19:30:49 +0200 |
| commit | 0916c5c6e536affca1f6f0c7693d68fb64843c1c (patch) | |
| tree | 1323d1656dc8770e8b9e24f997e323f77720022e | |
| parent | 0e9c319480d9cfb778b654bf2cd71e7bd31464f9 (diff) | |
| download | otp-0916c5c6e536affca1f6f0c7693d68fb64843c1c.tar.gz otp-0916c5c6e536affca1f6f0c7693d68fb64843c1c.tar.bz2 otp-0916c5c6e536affca1f6f0c7693d68fb64843c1c.zip | |
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.
| -rw-r--r-- | erts/emulator/beam/bif.tab | 1 | ||||
| -rw-r--r-- | erts/emulator/beam/erl_map.c | 19 | ||||
| -rw-r--r-- | lib/stdlib/src/maps.erl | 16 |
3 files changed, 7 insertions, 29 deletions
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) { diff --git a/lib/stdlib/src/maps.erl b/lib/stdlib/src/maps.erl index 60463feec2..6f5553c769 100644 --- a/lib/stdlib/src/maps.erl +++ b/lib/stdlib/src/maps.erl @@ -21,7 +21,7 @@ -module(maps). -export([get/3, filter/2,fold/3, - map/2, size/1, + map/2, size/1, new/0, update_with/3, update_with/4, without/2, with/2, iterator/1, next/1]). @@ -29,7 +29,7 @@ %% BIFs -export([get/2, find/2, from_list/1, is_key/2, keys/1, merge/2, - new/0, put/3, remove/2, take/2, + put/3, remove/2, take/2, to_list/1, update/3, values/1]). -opaque iterator() :: {term(), term(), iterator()} @@ -91,13 +91,6 @@ keys(_) -> erlang:nif_error(undef). merge(_,_) -> erlang:nif_error(undef). - --spec new() -> Map when - Map :: map(). - -new() -> erlang:nif_error(undef). - - %% Shadowed by erl_bif_types: maps:put/3 -spec put(Key,Value,Map1) -> Map2 when Key :: term(), @@ -157,6 +150,11 @@ values(_) -> erlang:nif_error(undef). %% End of BIFs +-spec new() -> Map when + Map :: #{}. + +new() -> #{}. + -spec update_with(Key,Fun,Map1) -> Map2 when Key :: term(), Map1 :: map(), |