diff options
| -rw-r--r-- | lib/compiler/src/v3_kernel.erl | 65 |
1 files changed, 63 insertions, 2 deletions
diff --git a/lib/compiler/src/v3_kernel.erl b/lib/compiler/src/v3_kernel.erl index 450547d691..a535cc4fc1 100644 --- a/lib/compiler/src/v3_kernel.erl +++ b/lib/compiler/src/v3_kernel.erl @@ -151,6 +151,7 @@ include_attribute(optional_callbacks) -> false; include_attribute(_) -> true. function({#c_var{name={F,Arity}=FA},Body}, St0) -> + %%io:format("~w/~w~n", [F,Arity]), try St1 = St0#kern{func=FA,ff=undefined,vcount=0,fcount=0,ds=cerl_sets:new()}, {#ifun{anno=Ab,vars=Kvs,body=B0},[],St2} = expr(Body, new_sub(), St1), @@ -1351,9 +1352,69 @@ select(T, Cs) -> [ C || C <- Cs, clause_con(C) =:= T ]. %% now separate them according to value. match_value(Us0, T, Cs0, Def, St0) -> - UCss = group_value(T, Us0, Cs0), + {Us1,Cs1,St1} = partition_intersection(T, Us0, Cs0, St0), + UCss = group_value(T, Us1, Cs1), %%ok = io:format("match_value ~p ~p~n", [T, Css]), - mapfoldl(fun ({Us,Cs}, St) -> match_clause(Us, Cs, Def, St) end, St0, UCss). + mapfoldl(fun ({Us,Cs}, St) -> match_clause(Us, Cs, Def, St) end, St1, UCss). + +%% partition_intersection +%% Partitions a map into two maps with the most common keys to the first map. +%% case <M> of +%% <#{a}> +%% <#{a,b}> +%% <#{a,c}> +%% <#{c}> +%% end +%% becomes +%% case <M,M> of +%% <#{a}, #{ }> +%% <#{a}, #{b}> +%% <#{ }, #{c}> +%% <#{a}, #{c}> +%% end +%% The intention is to group as many keys together as possible and thus +%% reduce the number of lookups to that key. +partition_intersection(k_map, [U|_]=Us0, [_,_|_]=Cs0,St0) -> + Ps = [clause_val(C) || C <- Cs0], + case find_key_partition(Ps) of + no_partition -> + {Us0,Cs0,St0}; + Ks -> + {Cs1,St1} = mapfoldl(fun(#iclause{pats=[Arg|Args]}=C, Sti) -> + {{Arg1,Arg2},St} = partition_key_intersection(Arg, Ks, Sti), + {C#iclause{pats=[Arg1,Arg2|Args]}, St} + end, St0, Cs0), + {[U|Us0],Cs1,St1} + end; +partition_intersection(_, Us, Cs, St) -> + {Us,Cs,St}. + +partition_key_intersection(#k_map{es=Pairs}=Map,Ks,St0) -> + F = fun(#k_map_pair{key=Key}) -> member(map_key_clean(Key), Ks) end, + {Ps1,Ps2} = partition(F, Pairs), + {{Map#k_map{es=Ps1},Map#k_map{es=Ps2}},St0}; +partition_key_intersection(#ialias{pat=Map}=Alias,Ks,St0) -> + %% only alias one of them + {{Map1,Map2},St1} = partition_key_intersection(Map, Ks, St0), + {{Map1,Alias#ialias{pat=Map2}},St1}. + +% Only check for the complete intersection of keys and not commonality +find_key_partition(Ps) -> + Sets = [sets:from_list(Ks)||Ks <- Ps], + Is = sets:intersection(Sets), + case sets:to_list(Is) of + [] -> no_partition; + KeyIntersection -> + %% Check if the intersection are all keys in all clauses. + %% Don't split if they are since this will only + %% infer extra is_map instructions with no gain. + All = foldl(fun (Kset, Bool) -> + Bool andalso sets:is_subset(Kset, Is) + end, true, Sets), + if All -> no_partition; + true -> KeyIntersection + end + end. %% group_value([Clause]) -> [[Clause]]. %% Group clauses according to value. Here we know that |