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-rw-r--r--lib/compiler/src/beam_bsm.erl1
-rw-r--r--lib/compiler/src/beam_disasm.erl6
-rw-r--r--lib/compiler/src/beam_validator.erl5
-rw-r--r--lib/compiler/src/compile.erl7
-rw-r--r--lib/compiler/src/core_lib.erl4
-rw-r--r--lib/compiler/src/sys_core_fold.erl143
-rw-r--r--lib/compiler/src/v3_codegen.erl138
-rw-r--r--lib/compiler/src/v3_core.erl510
-rw-r--r--lib/compiler/src/v3_kernel.erl105
-rw-r--r--lib/compiler/src/v3_kernel.hrl4
-rw-r--r--lib/compiler/src/v3_kernel_pp.erl17
-rw-r--r--lib/compiler/src/v3_life.erl14
12 files changed, 513 insertions, 441 deletions
diff --git a/lib/compiler/src/beam_bsm.erl b/lib/compiler/src/beam_bsm.erl
index fdfcb08125..d54c2a9fde 100644
--- a/lib/compiler/src/beam_bsm.erl
+++ b/lib/compiler/src/beam_bsm.erl
@@ -209,6 +209,7 @@ btb_reaches_match_2([{call,Arity,{f,Lbl}}|Is], Regs, D) ->
btb_reaches_match_2([{apply,Arity}|Is], Regs, D) ->
btb_call(Arity+2, apply, Regs, Is, D);
btb_reaches_match_2([{call_fun,Live}=I|Is], Regs, D) ->
+ btb_ensure_not_used([{x,Live}], I, Regs),
btb_call(Live, I, Regs, Is, D);
btb_reaches_match_2([{make_fun2,_,_,_,Live}|Is], Regs, D) ->
btb_call(Live, make_fun2, Regs, Is, D);
diff --git a/lib/compiler/src/beam_disasm.erl b/lib/compiler/src/beam_disasm.erl
index e0d0d0fd1d..57fdf95677 100644
--- a/lib/compiler/src/beam_disasm.erl
+++ b/lib/compiler/src/beam_disasm.erl
@@ -1134,7 +1134,7 @@ resolve_inst({line,[Index]},_,_,_) ->
{line,resolve_arg(Index)};
%%
-%% R17A.
+%% 17.0
%%
resolve_inst({put_map_assoc,Args},_,_,_) ->
[FLbl,Src,Dst,{u,N},{{z,1},{u,_Len},List0}] = Args,
@@ -1150,6 +1150,10 @@ resolve_inst({is_map,Args0},_,_,_) ->
[FLbl|Args] = resolve_args(Args0),
{test, is_map, FLbl, Args};
+resolve_inst({has_map_field,Args0},_,_,_) ->
+ [FLbl|Args] = resolve_args(Args0),
+ {test,has_map_field,FLbl,Args};
+
resolve_inst({get_map_element,Args},_,_,_) ->
[FLbl,Src,Key,Dst] = resolve_args(Args),
{get_map_element,FLbl,Src,Key,Dst};
diff --git a/lib/compiler/src/beam_validator.erl b/lib/compiler/src/beam_validator.erl
index 97f84da08f..2486d486ed 100644
--- a/lib/compiler/src/beam_validator.erl
+++ b/lib/compiler/src/beam_validator.erl
@@ -574,6 +574,7 @@ valfun_4({apply,Live}, Vst) ->
valfun_4({apply_last,Live,_}, Vst) ->
tail_call(apply, Live+2, Vst);
valfun_4({call_fun,Live}, Vst) ->
+ validate_src([{x,Live}], Vst),
call('fun', Live+1, Vst);
valfun_4({call,Live,Func}, Vst) ->
call(Func, Live, Vst);
@@ -881,7 +882,7 @@ valfun_4(_, _) ->
verify_put_map(Fail, Src, Dst, Live, List, Vst0) ->
verify_live(Live, Vst0),
verify_y_init(Vst0),
- [assert_term(Term, Vst0) || Term <- List],
+ foreach(fun (Term) -> assert_term(Term, Vst0) end, List),
assert_term(Src, Vst0),
Vst1 = heap_alloc(0, Vst0),
Vst2 = branch_state(Fail, Vst1),
@@ -908,7 +909,7 @@ validate_bs_skip_utf(Fail, Ctx, Live, Vst0) ->
branch_state(Fail, Vst).
%%
-%% Special state handling for setelement/3 and the set_tuple_element/3 instruction.
+%% Special state handling for setelement/3 and set_tuple_element/3 instructions.
%% A possibility for garbage collection must not occur between setelement/3 and
%% set_tuple_element/3.
%%
diff --git a/lib/compiler/src/compile.erl b/lib/compiler/src/compile.erl
index 0bb4de6f17..e79fe41f9b 100644
--- a/lib/compiler/src/compile.erl
+++ b/lib/compiler/src/compile.erl
@@ -623,9 +623,11 @@ core_passes() ->
[{core_old_inliner,fun test_old_inliner/1,fun core_old_inliner/1},
{iff,doldinline,{listing,"oldinline"}},
?pass(core_fold_module),
+ {iff,dcorefold,{listing,"corefold"}},
{core_inline_module,fun test_core_inliner/1,fun core_inline_module/1},
{iff,dinline,{listing,"inline"}},
- {core_fold_after_inlining,fun test_core_inliner/1,fun core_fold_module_after_inlining/1},
+ {core_fold_after_inlining,fun test_any_inliner/1,
+ fun core_fold_module_after_inlining/1},
?pass(core_transforms)]},
{iff,dcopt,{listing,"copt"}},
{iff,'to_core',{done,"core"}}]}
@@ -1171,6 +1173,9 @@ test_core_inliner(#compile{options=Opts}) ->
end, Opts)
end.
+test_any_inliner(St) ->
+ test_old_inliner(St) orelse test_core_inliner(St).
+
core_old_inliner(#compile{code=Code0,options=Opts}=St) ->
{ok,Code} = sys_core_inline:module(Code0, Opts),
{ok,St#compile{code=Code}}.
diff --git a/lib/compiler/src/core_lib.erl b/lib/compiler/src/core_lib.erl
index f506901099..ed181e3baa 100644
--- a/lib/compiler/src/core_lib.erl
+++ b/lib/compiler/src/core_lib.erl
@@ -105,8 +105,8 @@ vu_expr(V, #c_cons{hd=H,tl=T}) ->
vu_expr(V, H) orelse vu_expr(V, T);
vu_expr(V, #c_tuple{es=Es}) ->
vu_expr_list(V, Es);
-vu_expr(V, #c_map{es=Es}) ->
- vu_expr_list(V, Es);
+vu_expr(V, #c_map{var=M,es=Es}) ->
+ vu_expr(V, M) orelse vu_expr_list(V, Es);
vu_expr(V, #c_map_pair{key=Key,val=Val}) ->
vu_expr_list(V, [Key,Val]);
vu_expr(V, #c_binary{segments=Ss}) ->
diff --git a/lib/compiler/src/sys_core_fold.erl b/lib/compiler/src/sys_core_fold.erl
index 1cdbac5693..e2b9213891 100644
--- a/lib/compiler/src/sys_core_fold.erl
+++ b/lib/compiler/src/sys_core_fold.erl
@@ -305,6 +305,10 @@ expr(#c_let{}=Let, Ctxt, Sub) ->
%% Now recursively re-process the new expression.
expr(Expr, Ctxt, sub_new_preserve_types(Sub))
end;
+expr(#c_letrec{body=#c_var{}}=Letrec, effect, _Sub) ->
+ %% This is named fun in an 'effect' context. Warn and ignore.
+ add_warning(Letrec, useless_building),
+ void();
expr(#c_letrec{defs=Fs0,body=B0}=Letrec, Ctxt, Sub) ->
Fs1 = map(fun ({Name,Fb}) ->
{Name,expr(Fb, {letrec,Ctxt}, Sub)}
@@ -349,7 +353,12 @@ expr(#c_case{}=Case0, Ctxt, Sub) ->
Case = Case1#c_case{arg=Arg2,clauses=Cs2},
warn_no_clause_match(Case1, Case),
Expr = eval_case(Case, Sub),
- bsm_an(Expr);
+ case move_case_into_arg(Case, Sub) of
+ impossible ->
+ bsm_an(Expr);
+ Other ->
+ expr(Other, Ctxt, sub_new_preserve_types(Sub))
+ end;
Other ->
expr(Other, Ctxt, Sub)
end;
@@ -598,6 +607,14 @@ eval_binary_1([#c_bitstr{val=#c_literal{val=Val},size=#c_literal{val=Sz},
error:_ ->
throw(impossible)
end;
+eval_binary_1([#c_bitstr{val=#c_literal{},size=#c_literal{},
+ unit=#c_literal{},type=#c_literal{},
+ flags=#c_cons{}=Flags}=Bitstr|Ss], Acc0) ->
+ case cerl:fold_literal(Flags) of
+ #c_literal{} = Flags1 ->
+ eval_binary_1([Bitstr#c_bitstr{flags=Flags1}|Ss], Acc0);
+ _ -> throw(impossible)
+ end;
eval_binary_1([], Acc) -> Acc;
eval_binary_1(_, _) -> throw(impossible).
@@ -1536,9 +1553,17 @@ map_pair_pattern_list(Ps0, Isub, Osub0) ->
{Ps,{_,Osub}} = mapfoldl(fun map_pair_pattern/2, {Isub,Osub0}, Ps0),
{Ps,Osub}.
-map_pair_pattern(#c_map_pair{op=#c_literal{val=exact},key=K0,val=V0}=Pair, {Isub,Osub0}) ->
- {K,Osub1} = pattern(K0, Isub, Osub0),
- {V,Osub} = pattern(V0, Isub, Osub1),
+map_pair_pattern(#c_map_pair{op=#c_literal{val=exact},key=K0,val=V0}=Pair,{Isub,Osub0}) ->
+ {K,Osub1} = case cerl:type(K0) of
+ binary ->
+ K1 = eval_binary(K0),
+ case cerl:type(K1) of
+ literal -> {K1,Osub0};
+ _ -> pattern(K0,Isub,Osub0)
+ end;
+ _ -> pattern(K0,Isub,Osub0)
+ end,
+ {V,Osub} = pattern(V0,Isub,Osub1),
{Pair#c_map_pair{key=K,val=V},{Isub,Osub}}.
bin_pattern_list(Ps0, Isub, Osub0) ->
@@ -1920,14 +1945,45 @@ opt_bool_case_guard(Arg, [#c_clause{pats=[#c_literal{val=false}]}=Fc,Tc]) ->
%% last clause is guaranteed to match so if there is only one clause
%% with a pattern containing only variables then rewrite to a let.
-eval_case(#c_case{arg=E,clauses=[#c_clause{pats=Ps0,body=B}]}, Sub) ->
+eval_case(#c_case{arg=E,clauses=[#c_clause{pats=Ps0,
+ guard=#c_literal{val=true},
+ body=B}]}=Case, Sub) ->
Es = case cerl:is_c_values(E) of
true -> cerl:values_es(E);
false -> [E]
end,
- {true,Bs} = cerl_clauses:match_list(Ps0, Es),
- {Ps,As} = unzip(Bs),
- expr(#c_let{vars=Ps,arg=core_lib:make_values(As),body=B}, sub_new(Sub));
+ %% Consider:
+ %%
+ %% case SomeSideEffect() of
+ %% X=Y -> ...
+ %% end
+ %%
+ %% We must not rewrite it to:
+ %%
+ %% let <X,Y> = <SomeSideEffect(),SomeSideEffect()> in ...
+ %%
+ %% because SomeSideEffect() would be evaluated twice.
+ %%
+ %% Instead we must evaluate the case expression in an outer let
+ %% like this:
+ %%
+ %% let NewVar = SomeSideEffect() in
+ %% let <X,Y> = <NewVar,NewVar> in ...
+ %%
+ Vs = make_vars([], length(Es)),
+ case cerl_clauses:match_list(Ps0, Vs) of
+ {false,_} ->
+ %% This can only happen if the Core Erlang code is
+ %% handwritten or generated by another code generator
+ %% than v3_core. Assuming that the Core Erlang program
+ %% is correct, the clause will always match at run-time.
+ Case;
+ {true,Bs} ->
+ {Ps,As} = unzip(Bs),
+ InnerLet = cerl:c_let(Ps, core_lib:make_values(As), B),
+ Let = cerl:c_let(Vs, E, InnerLet),
+ expr(Let, sub_new(Sub))
+ end;
eval_case(Case, _) -> Case.
%% case_opt(CaseArg, [Clause]) -> {CaseArg,[Clause]}.
@@ -2555,6 +2611,77 @@ opt_simple_let_2(Let, Vs0, Arg0, Body, value, Sub) ->
value, Sub)
end.
+move_case_into_arg(#c_case{arg=#c_let{vars=OuterVars0,arg=OuterArg,
+ body=InnerArg0}=Outer,
+ clauses=InnerClauses}=Inner, Sub) ->
+ %%
+ %% case let <OuterVars> = <OuterArg> in <InnerArg> of
+ %% <InnerClauses>
+ %% end
+ %%
+ %% ==>
+ %%
+ %% let <OuterVars> = <OuterArg>
+ %% in case <InnerArg> of <InnerClauses> end
+ %%
+ ScopeSub0 = sub_subst_scope(Sub#sub{t=[]}),
+ {OuterVars,ScopeSub} = pattern_list(OuterVars0, ScopeSub0),
+ InnerArg = body(InnerArg0, ScopeSub),
+ Outer#c_let{vars=OuterVars,arg=OuterArg,
+ body=Inner#c_case{arg=InnerArg,clauses=InnerClauses}};
+move_case_into_arg(#c_case{arg=#c_case{arg=OuterArg,
+ clauses=[OuterCa0,OuterCb]}=Outer,
+ clauses=InnerClauses}=Inner0, Sub) ->
+ case is_failing_clause(OuterCb) of
+ true ->
+ #c_clause{pats=OuterPats0,guard=OuterGuard0,
+ body=InnerArg0} = OuterCa0,
+ %%
+ %% case case <OuterArg> of
+ %% <OuterPats> when <OuterGuard> -> <InnerArg>
+ %% <OuterCb>
+ %% ...
+ %% end of
+ %% <InnerClauses>
+ %% end
+ %%
+ %% ==>
+ %%
+ %% case <OuterArg> of
+ %% <OuterPats> when <OuterGuard> ->
+ %% case <InnerArg> of <InnerClauses> end
+ %% <OuterCb>
+ %% end
+ %%
+ ScopeSub0 = sub_subst_scope(Sub#sub{t=[]}),
+ {OuterPats,ScopeSub} = pattern_list(OuterPats0, ScopeSub0),
+ OuterGuard = guard(OuterGuard0, ScopeSub),
+ InnerArg = body(InnerArg0, ScopeSub),
+ Inner = Inner0#c_case{arg=InnerArg,clauses=InnerClauses},
+ OuterCa = OuterCa0#c_clause{pats=OuterPats,guard=OuterGuard,
+ body=Inner},
+ Outer#c_case{arg=OuterArg,
+ clauses=[OuterCa,OuterCb]};
+ false ->
+ impossible
+ end;
+move_case_into_arg(#c_case{arg=#c_seq{arg=OuterArg,body=InnerArg}=Outer,
+ clauses=InnerClauses}=Inner, _Sub) ->
+ %%
+ %% case do <OuterArg> <InnerArg> of
+ %% <InnerClauses>
+ %% end
+ %%
+ %% ==>
+ %%
+ %% do <OuterArg>
+ %% case <InnerArg> of <InerClauses> end
+ %%
+ Outer#c_seq{arg=OuterArg,
+ body=Inner#c_case{arg=InnerArg,clauses=InnerClauses}};
+move_case_into_arg(_, _) ->
+ impossible.
+
%% In guards only, rewrite a case in a let argument like
%%
%% let <Var> = case <> of
diff --git a/lib/compiler/src/v3_codegen.erl b/lib/compiler/src/v3_codegen.erl
index c8735a76e8..4d155c0fd0 100644
--- a/lib/compiler/src/v3_codegen.erl
+++ b/lib/compiler/src/v3_codegen.erl
@@ -459,7 +459,7 @@ basic_block([Le|Les], Acc) ->
%% sets that may garbage collect are not allowed in basic blocks.
collect_block({set,_,{binary,_}}) -> no_block;
-collect_block({set,_,{map,_,_}}) -> no_block;
+collect_block({set,_,{map,_,_,_}}) -> no_block;
collect_block({set,_,_}) -> include;
collect_block({call,{var,_}=Var,As,_Rs}) -> {block_end,As++[Var]};
collect_block({call,Func,As,_Rs}) -> {block_end,As++func_vars(Func)};
@@ -928,7 +928,7 @@ select_extract_tuple(Src, Vs, I, Vdb, Bef, St) ->
select_map(Scs, V, Tf, Vf, Bef, St0) ->
Reg = fetch_var(V, Bef),
{Is,Aft,St1} =
- match_fmf(fun(#l{ke={val_clause,{map,Es},B},i=I,vdb=Vdb}, Fail, St1) ->
+ match_fmf(fun(#l{ke={val_clause,{map,_,Es},B},i=I,vdb=Vdb}, Fail, St1) ->
select_map_val(V, Es, B, Fail, I, Vdb, Bef, St1)
end, Vf, St0, Scs),
{[{test,is_map,{f,Tf},[Reg]}|Is],Aft,St1}.
@@ -1488,55 +1488,35 @@ set_cg([{var,R}], {binary,Segs}, Le, Vdb, Bef,
%% Now generate the complete code for constructing the binary.
Code = cg_binary(PutCode, Target, Temp, Fail, MaxRegs, Le#l.a),
{Sis++Code,Aft,St};
-set_cg([{var,R}], {map,SrcMap,Es0}, Le, Vdb, Bef,
+set_cg([{var,R}], {map,Op,Map,Es}, Le, Vdb, Bef,
#cg{in_catch=InCatch,bfail=Bfail}=St) ->
+
Fail = {f,Bfail},
{Sis,Int0} =
case InCatch of
true -> adjust_stack(Bef, Le#l.i, Le#l.i+1, Vdb);
false -> {[],Bef}
end,
+ SrcReg = cg_reg_arg(Map,Int0),
Line = line(Le#l.a),
- SrcReg = case SrcMap of
- {var,SrcVar} -> fetch_var(SrcVar, Int0);
- _ -> SrcMap
- end,
- {Assoc,Exact} =
- try
- cg_map_pairs(Es0)
- catch
- throw:badarg ->
- {[],[{{float,0.0},{atom,badarg}},
- {{integer,0},{atom,badarg}}]}
- end,
- F = fun ({K,{var,V}}) -> [K,fetch_var(V, Int0)];
- ({K,E}) -> [K,E]
- end,
- AssocList = flatmap(F, Assoc),
- ExactList = flatmap(F, Exact),
- Live0 = max_reg(Bef#sr.reg),
- Int1 = clear_dead(Int0, Le#l.i, Vdb),
- Aft = Bef#sr{reg=put_reg(R, Int1#sr.reg)},
- Target = fetch_reg(R, Aft#sr.reg),
- Code = [Line] ++
- case {AssocList,ExactList} of
- {[_|_],[]} ->
- [{put_map_assoc,Fail,SrcReg,Target,Live0,{list,AssocList}}];
- {[_|_],[_|_]} ->
- Live = case Target of
- {x,TargetX} when TargetX =:= Live0 ->
- Live0 + 1;
- _ ->
- Live0
- end,
- [{put_map_assoc,Fail,SrcReg,Target,Live0,{list,AssocList}},
- {put_map_exact,Fail,Target,Target,Live,{list,ExactList}}];
- {[],[_|_]} ->
- [{put_map_exact,Fail,SrcReg,Target,Live0,{list,ExactList}}];
- {[],[]} ->
- [{put_map_assoc,Fail,SrcReg,Target,Live0,{list,[]}}]
- end,
- {Sis++Code,Aft,St};
+
+ %% The instruction needs to store keys in term sorted order
+ %% All keys has to be unique here
+ Pairs = map_pair_strip_and_termsort(Es),
+
+ %% fetch registers for values to be put into the map
+ List = flatmap(fun({K,V}) -> [K,cg_reg_arg(V,Int0)] end, Pairs),
+
+ Live = max_reg(Bef#sr.reg),
+ Int1 = Int0#sr{reg=put_reg(R, Int0#sr.reg)},
+ Aft = clear_dead(Int1, Le#l.i, Vdb),
+ Target = fetch_reg(R, Int1#sr.reg),
+
+ I = case Op of
+ assoc -> put_map_assoc;
+ exact -> put_map_exact
+ end,
+ {Sis++[Line]++[{I,Fail,SrcReg,Target,Live,{list,List}}],Aft,St};
set_cg([{var,R}], Con, Le, Vdb, Bef, St) ->
%% Find a place for the return register first.
Int = Bef#sr{reg=put_reg(R, Bef#sr.reg)},
@@ -1549,70 +1529,12 @@ set_cg([{var,R}], Con, Le, Vdb, Bef, St) ->
end,
{Ais,clear_dead(Int, Le#l.i, Vdb),St}.
-%% cg_map_pairs(MapPairs) -> {Assoc,Exact}
-%% Assoc = Exact = [{K,V}]
-%%
-%% Remove multiple assignments to the same key, and return
-%% one list key-value list with all keys that may or may not exist
-%% (Assoc), and one with keys that must exist (Exact).
-%%
-
-cg_map_pairs(Es0) ->
- Es = cg_map_pairs_1(Es0, 0),
- R0 = sofs:relation(Es),
- R1 = sofs:relation_to_family(R0),
- R2 = sofs:to_external(R1),
-
- %% R2 is now [{KeyValue,[{Order,Op,OriginalKey,Value}]}]
- R3 = [begin
- %% The value for the last pair determines the value.
- {_,_,_,V} = lists:last(Vs),
- {Op,{_,SortOrder}=K} = map_pair_op_and_key(Vs),
- {Op,{SortOrder,K,V}}
- end || {_,Vs} <- R2],
-
- %% R3 is now [{Op,{Key,Value}}]
- R = termsort(R3),
-
- %% R4 is now sorted with all alloc first in the list, followed by
- %% all exact.
- {Assoc,Exact} = lists:partition(fun({Op,_}) -> Op =:= assoc end, R),
- {[{K,V} || {_,{_,K,V}} <- Assoc],
- [{K,V} || {_,{_,K,V}} <- Exact]}.
-
-cg_map_pairs_1([{map_pair_assoc,{_,Kv}=K,V}|T], Order) ->
- [{Kv,{Order,assoc,K,V}}|cg_map_pairs_1(T, Order+1)];
-cg_map_pairs_1([{map_pair_exact,{_,Kv}=K,V}|T], Order) ->
- [{Kv,{Order,exact,K,V}}|cg_map_pairs_1(T, Order+1)];
-cg_map_pairs_1([], _) -> [].
-
-%% map_pair_op_and_key({_,Op,K,_}) -> {Operator,Key}
-%% Determine the operator and key to use. Throw a 'badarg'
-%% exception if there are contradictory exact updates.
-
-map_pair_op_and_key(L) ->
- case [K || {_,exact,K,_} <- L] of
- [K] ->
- %% There is a single ':=' operator. Use that key.
- {exact,K};
- [K|T] ->
- %% There is more than one ':=' operator. All of them
- %% must have the same key.
- case lists:all(fun(E) -> E =:= K end, T) of
- true ->
- {exact,K};
- false ->
- %% Some keys are different, e.g. 1 and 1.0.
- throw(badarg)
- end;
- [] ->
- %% Only '=>' operators. Use the first key in the list.
- [{_,assoc,K,_}|_] = L,
- {assoc,K}
- end.
-
-termsort(Ls) ->
- lists:sort(fun(A,B) -> erts_internal:cmp_term(A,B) < 0 end, Ls).
+map_pair_strip_and_termsort(Es) ->
+ %% format in
+ %% [{map_pair,K,V}]
+ %% where K is for example {integer, 1} and we want to sort on 1.
+ Ls = [{K,V}||{_,K,V}<-Es],
+ lists:sort(fun({{_,A},_},{{_,B},_}) -> erts_internal:cmp_term(A,B) < 0 end, Ls).
%%%
%%% Code generation for constructing binaries.
@@ -2085,7 +2007,7 @@ load_vars(Vs, Regs) ->
foldl(fun ({var,V}, Rs) -> put_reg(V, Rs) end, Regs, Vs).
%% put_reg(Val, Regs) -> Regs.
-%% find_reg(Val, Regs) -> ok{r{R}} | error.
+%% find_reg(Val, Regs) -> {ok,r{R}} | error.
%% fetch_reg(Val, Regs) -> r{R}.
%% Functions to interface the registers.
diff --git a/lib/compiler/src/v3_core.erl b/lib/compiler/src/v3_core.erl
index e30bfa729c..3435a46ca9 100644
--- a/lib/compiler/src/v3_core.erl
+++ b/lib/compiler/src/v3_core.erl
@@ -74,7 +74,7 @@
-export([module/2,format_error/1]).
-import(lists, [reverse/1,reverse/2,map/2,member/2,foldl/3,foldr/3,mapfoldl/3,
- splitwith/2,keyfind/3,sort/1,foreach/2]).
+ splitwith/2,keyfind/3,sort/1,foreach/2,droplast/1,last/1]).
-import(ordsets, [add_element/2,del_element/2,is_element/2,
union/1,union/2,intersection/2,subtract/2]).
-import(cerl, [ann_c_cons/3,ann_c_cons_skel/3,ann_c_tuple/2,c_tuple/1]).
@@ -101,6 +101,8 @@
-record(ireceive2, {anno=#a{},clauses,timeout,action}).
-record(iset, {anno=#a{},var,arg}).
-record(itry, {anno=#a{},args,vars,body,evars,handler}).
+-record(ifilter, {anno=#a{},arg}).
+-record(igen, {anno=#a{},acc_pat,acc_guard,skip_pat,tail,tail_pat,arg}).
-type iapply() :: #iapply{}.
-type ibinary() :: #ibinary{}.
@@ -117,10 +119,13 @@
-type ireceive2() :: #ireceive2{}.
-type iset() :: #iset{}.
-type itry() :: #itry{}.
+-type ifilter() :: #ifilter{}.
+-type igen() :: #igen{}.
-type i() :: iapply() | ibinary() | icall() | icase() | icatch()
| iclause() | ifun() | iletrec() | imatch() | iprimop()
- | iprotect() | ireceive1() | ireceive2() | iset() | itry().
+ | iprotect() | ireceive1() | ireceive2() | iset() | itry()
+ | ifilter() | igen().
-type warning() :: {file:filename(), [{integer(), module(), term()}]}.
@@ -226,13 +231,13 @@ guard(Gs0, St0) ->
Gt1 = guard_tests(Gt0),
L = element(2, Gt1),
{op,L,'or',Gt1,Rhs}
- end, guard_tests(last(Gs0)), first(Gs0)),
+ end, guard_tests(last(Gs0)), droplast(Gs0)),
{Gs,St} = gexpr_top(Gs1, St0#core{in_guard=true}),
{Gs,St#core{in_guard=false}}.
guard_tests(Gs) ->
L = element(2, hd(Gs)),
- {protect,L,foldr(fun (G, Rhs) -> {op,L,'and',G,Rhs} end, last(Gs), first(Gs))}.
+ {protect,L,foldr(fun (G, Rhs) -> {op,L,'and',G,Rhs} end, last(Gs), droplast(Gs))}.
%% gexpr_top(Expr, State) -> {Cexpr,State}.
%% Generate an internal core expression of a guard test. Explicitly
@@ -479,8 +484,9 @@ expr({cons,L,H0,T0}, St0) ->
{T1,Tps,St2} = safe(T0, St1),
A = lineno_anno(L, St2),
{ann_c_cons(A, H1, T1),Hps ++ Tps,St2};
-expr({lc,L,E,Qs}, St) ->
- lc_tq(L, E, Qs, #c_literal{anno=lineno_anno(L, St),val=[]}, St);
+expr({lc,L,E,Qs0}, St0) ->
+ {Qs1,St1} = preprocess_quals(L, Qs0, St0),
+ lc_tq(L, E, Qs1, #c_literal{anno=lineno_anno(L, St1),val=[]}, St1);
expr({bc,L,E,Qs}, St) ->
bc_tq(L, E, Qs, {nil,L}, St);
expr({tuple,L,Es0}, St0) ->
@@ -513,7 +519,7 @@ expr({bin,L,Es0}, St0) ->
end;
expr({block,_,Es0}, St0) ->
%% Inline the block directly.
- {Es1,St1} = exprs(first(Es0), St0),
+ {Es1,St1} = exprs(droplast(Es0), St0),
{E1,Eps,St2} = expr(last(Es0), St1),
{E1,Es1 ++ Eps,St2};
expr({'if',L,Cs0}, St0) ->
@@ -647,7 +653,7 @@ expr({match,L,P0,E0}, St0) ->
Other when not is_atom(Other) ->
{#imatch{anno=#a{anno=Lanno},pat=P2,arg=E2,fc=Fc},Eps,St4}
end;
-expr({op,_,'++',{lc,Llc,E,Qs},More}, St0) ->
+expr({op,_,'++',{lc,Llc,E,Qs0},More}, St0) ->
%% Optimise '++' here because of the list comprehension algorithm.
%%
%% To avoid achieving quadratic complexity if there is a chain of
@@ -655,7 +661,8 @@ expr({op,_,'++',{lc,Llc,E,Qs},More}, St0) ->
%% evaluation of More now. Evaluating More here could also reduce the
%% number variables in the environment for letrec.
{Mc,Mps,St1} = safe(More, St0),
- {Y,Yps,St} = lc_tq(Llc, E, Qs, Mc, St1),
+ {Qs,St2} = preprocess_quals(Llc, Qs0, St1),
+ {Y,Yps,St} = lc_tq(Llc, E, Qs, Mc, St2),
{Y,Mps++Yps,St};
expr({op,L,'andalso',E1,E2}, St0) ->
{#c_var{name=V0},St} = new_var(L, St0),
@@ -889,133 +896,45 @@ fun_tq({_,_,Name}=Id, Cs0, L, St0, NameInfo) ->
%% lc_tq(Line, Exp, [Qualifier], Mc, State) -> {LetRec,[PreExp],State}.
%% This TQ from Simon PJ pp 127-138.
-%% This gets a bit messy as we must transform all directly here. We
-%% recognise guard tests and try to fold them together and join to a
-%% preceding generators, this should give us better and more compact
-%% code.
-lc_tq(Line, E, [{generate,Lg,P,G}|Qs0], Mc, St0) ->
- {Gs,Qs1} = splitwith(fun is_guard_test/1, Qs0),
+lc_tq(Line, E, [#igen{anno=GAnno,acc_pat=AccPat,acc_guard=AccGuard,
+ skip_pat=SkipPat,tail=Tail,tail_pat=TailPat,
+ arg={Pre,Arg}}|Qs], Mc, St0) ->
{Name,St1} = new_fun_name("lc", St0),
- {Head,St2} = new_var(St1),
- {Tname,St3} = new_var_name(St2),
- LA = lineno_anno(Line, St3),
- LAnno = #a{anno=LA},
- Tail = #c_var{anno=LA,name=Tname},
- {Arg,St4} = new_var(St3),
- {Nc,[],St5} = expr({call,Lg,{atom,Lg,Name},[{var,Lg,Tname}]}, St4),
- {Guardc,St6} = lc_guard_tests(Gs, St5), %These are always flat!
- {Lc,Lps,St7} = lc_tq(Line, E, Qs1, Nc, St6),
- {Pc,St8} = list_gen_pattern(P, Line, St7),
- {Gc,Gps,St9} = safe(G, St8), %Will be a function argument!
- Fc = function_clause([Arg], LA, {Name,1}),
-
- %% Avoid constructing a default clause if the list comprehension
- %% only has a variable as generator and there are no guard
- %% tests. In other words, if the comprehension is equivalent to
- %% lists:map/2.
- Cs0 = case {Guardc, Pc} of
- {[], #c_var{}} ->
- [#iclause{anno=LAnno,
- pats=[#c_literal{anno=LA,val=[]}],guard=[],
- body=[Mc]}];
- _ ->
- [#iclause{anno=#a{anno=[compiler_generated|LA]},
- pats=[ann_c_cons(LA, Head, Tail)],
- guard=[],
- body=[Nc]},
- #iclause{anno=LAnno,
- pats=[#c_literal{anno=LA,val=[]}],guard=[],
- body=[Mc]}]
- end,
- Cs = case Pc of
- nomatch -> Cs0;
- _ ->
- [#iclause{anno=LAnno,
- pats=[ann_c_cons(LA, Pc, Tail)],
- guard=Guardc,
- body=Lps ++ [Lc]}|Cs0]
- end,
- Fun = #ifun{anno=LAnno,id=[],vars=[Arg],clauses=Cs,fc=Fc},
- {#iletrec{anno=LAnno,defs=[{{Name,1},Fun}],
- body=Gps ++ [#iapply{anno=LAnno,
- op=#c_var{anno=LA,name={Name,1}},
- args=[Gc]}]},
- [],St9};
-lc_tq(Line, E, [{b_generate,Lg,P,G}|Qs0], Mc, St0) ->
- {Gs,Qs1} = splitwith(fun is_guard_test/1, Qs0),
- {Name,St1} = new_fun_name("blc", St0),
LA = lineno_anno(Line, St1),
LAnno = #a{anno=LA},
- HeadBinPattern = pattern(P, St1),
- #c_binary{segments=Ps0} = HeadBinPattern,
- {Ps,Tail,St2} = append_tail_segment(Ps0, St1),
- {EPs,St3} = emasculate_segments(Ps, St2),
- Pattern = HeadBinPattern#c_binary{segments=Ps},
- EPattern = HeadBinPattern#c_binary{segments=EPs},
- {Arg,St4} = new_var(St3),
- {Guardc,St5} = lc_guard_tests(Gs, St4), %These are always flat!
- Tname = Tail#c_var.name,
- {Nc,[],St6} = expr({call,Lg,{atom,Lg,Name},[{var,Lg,Tname}]}, St5),
- {Bc,Bps,St7} = lc_tq(Line, E, Qs1, Nc, St6),
- {Gc,Gps,St10} = safe(G, St7), %Will be a function argument!
- Fc = function_clause([Arg], LA, {Name,1}),
- {TailSegList,_,St} = append_tail_segment([], St10),
- Cs = [#iclause{anno=#a{anno=[compiler_generated|LA]},
- pats=[Pattern],
- guard=Guardc,
- body=Bps ++ [Bc]},
- #iclause{anno=#a{anno=[compiler_generated|LA]},
- pats=[EPattern],
- guard=[],
- body=[#iapply{anno=LAnno,
- op=#c_var{anno=LA,name={Name,1}},
- args=[Tail]}]},
- #iclause{anno=LAnno,
- pats=[#c_binary{anno=LA,segments=TailSegList}],guard=[],
- body=[Mc]}],
- Fun = #ifun{anno=LAnno,id=[],vars=[Arg],clauses=Cs,fc=Fc},
- {#iletrec{anno=LAnno,defs=[{{Name,1},Fun}],
- body=Gps ++ [#iapply{anno=LAnno,
- op=#c_var{anno=LA,name={Name,1}},
- args=[Gc]}]},
- [],St};
-lc_tq(Line, E, [Fil0|Qs0], Mc, St0) ->
- %% Special case sequences guard tests.
- LA = lineno_anno(element(2, Fil0), St0),
- LAnno = #a{anno=LA},
- case is_guard_test(Fil0) of
- true ->
- {Gs0,Qs1} = splitwith(fun is_guard_test/1, Qs0),
- {Lc,Lps,St1} = lc_tq(Line, E, Qs1, Mc, St0),
- {Gs,St2} = lc_guard_tests([Fil0|Gs0], St1), %These are always flat!
- {#icase{anno=LAnno,
- args=[],
- clauses=[#iclause{anno=LAnno,pats=[],
- guard=Gs,body=Lps ++ [Lc]}],
- fc=#iclause{anno=LAnno#a{anno=[compiler_generated|LA]},
- pats=[],guard=[],body=[Mc]}},
- [],St2};
- false ->
- {Lc,Lps,St1} = lc_tq(Line, E, Qs0, Mc, St0),
- {Fpat,St2} = new_var(St1),
- Fc = fail_clause([Fpat], LA,
- c_tuple([#c_literal{val=case_clause},Fpat])),
- %% Do a novars little optimisation here.
- {Filc,Fps,St3} = novars(Fil0, St2),
- {#icase{anno=LAnno,
- args=[Filc],
- clauses=[#iclause{anno=LAnno,
- pats=[#c_literal{anno=LA,val=true}],
- guard=[],
- body=Lps ++ [Lc]},
- #iclause{anno=LAnno#a{anno=[compiler_generated|LA]},
- pats=[#c_literal{anno=LA,val=false}],
- guard=[],
- body=[Mc]}],
- fc=Fc},
- Fps,St3}
- end;
+ F = #c_var{anno=LA,name={Name,1}},
+ Nc = #iapply{anno=GAnno,op=F,args=[Tail]},
+ {Var,St2} = new_var(St1),
+ Fc = function_clause([Var], LA, {Name,1}),
+ TailClause = #iclause{anno=LAnno,pats=[TailPat],guard=[],body=[Mc]},
+ Cs0 = case {AccPat,AccGuard} of
+ {SkipPat,[]} ->
+ %% Skip and accumulator patterns are the same and there is
+ %% no guard, no need to generate a skip clause.
+ [TailClause];
+ _ ->
+ [#iclause{anno=#a{anno=[compiler_generated|LA]},
+ pats=[SkipPat],guard=[],body=[Nc]},
+ TailClause]
+ end,
+ {Cs,St4} = case AccPat of
+ nomatch ->
+ %% The accumulator pattern never matches, no need
+ %% for an accumulator clause.
+ {Cs0,St2};
+ _ ->
+ {Lc,Lps,St3} = lc_tq(Line, E, Qs, Nc, St2),
+ {[#iclause{anno=LAnno,pats=[AccPat],guard=AccGuard,
+ body=Lps ++ [Lc]}|Cs0],
+ St3}
+ end,
+ Fun = #ifun{anno=LAnno,id=[],vars=[Var],clauses=Cs,fc=Fc},
+ {#iletrec{anno=LAnno#a{anno=[list_comprehension|LA]},defs=[{{Name,1},Fun}],
+ body=Pre ++ [#iapply{anno=LAnno,op=F,args=[Arg]}]},
+ [],St4};
+lc_tq(Line, E, [#ifilter{}=Filter|Qs], Mc, St) ->
+ filter_tq(Line, E, Filter, Mc, St, Qs, fun lc_tq/5);
lc_tq(Line, E0, [], Mc0, St0) ->
{H1,Hps,St1} = safe(E0, St0),
{T1,Tps,St} = force_safe(Mc0, St1),
@@ -1025,143 +944,60 @@ lc_tq(Line, E0, [], Mc0, St0) ->
%% bc_tq(Line, Exp, [Qualifier], More, State) -> {LetRec,[PreExp],State}.
%% This TQ from Gustafsson ERLANG'05.
-%% This gets a bit messy as we must transform all directly here. We
-%% recognise guard tests and try to fold them together and join to a
-%% preceding generators, this should give us better and more compact
-%% code.
%% More could be transformed before calling bc_tq.
-bc_tq(Line, Exp, Qualifiers, _, St0) ->
+bc_tq(Line, Exp, Qs0, _, St0) ->
{BinVar,St1} = new_var(St0),
- {Sz,SzPre,St2} = bc_initial_size(Exp, Qualifiers, St1),
- {E,BcPre,St} = bc_tq1(Line, Exp, Qualifiers, BinVar, St2),
+ {Sz,SzPre,St2} = bc_initial_size(Exp, Qs0, St1),
+ {Qs,St3} = preprocess_quals(Line, Qs0, St2),
+ {E,BcPre,St} = bc_tq1(Line, Exp, Qs, BinVar, St3),
Pre = SzPre ++
[#iset{var=BinVar,
arg=#iprimop{name=#c_literal{val=bs_init_writable},
args=[Sz]}}] ++ BcPre,
{E,Pre,St}.
-bc_tq1(Line, E, [{generate,Lg,P,G}|Qs0], AccExpr, St0) ->
- {Gs,Qs1} = splitwith(fun is_guard_test/1, Qs0),
- {Name,St1} = new_fun_name("lbc", St0),
- LA = lineno_anno(Line, St1),
- {[Head,Tail,AccVar],St2} = new_vars(LA, 3, St1),
- LAnno = #a{anno=LA},
- {Arg,St3} = new_var(St2),
- NewMore = {call,Lg,{atom,Lg,Name},[{var,Lg,Tail#c_var.name},
- {var,Lg,AccVar#c_var.name}]},
- {Guardc,St4} = lc_guard_tests(Gs, St3), %These are always flat!
- {Lc,Lps,St5} = bc_tq1(Line, E, Qs1, AccVar, St4),
- {Nc,Nps,St6} = expr(NewMore, St5),
- {Pc,St7} = list_gen_pattern(P, Line, St6),
- {Gc,Gps,St8} = safe(G, St7), %Will be a function argument!
- Fc = function_clause([Arg,AccVar], LA, {Name,2}),
- Cs0 = case {Guardc, Pc} of
- {[], #c_var{}} ->
- [#iclause{anno=LAnno,
- pats=[#c_literal{anno=LA,val=[]},AccVar],guard=[],
- body=[AccVar]}];
- _ ->
- [#iclause{anno=#a{anno=[compiler_generated|LA]},
- pats=[ann_c_cons(LA, Head, Tail),AccVar],
- guard=[],
- body=Nps ++ [Nc]},
- #iclause{anno=LAnno,
- pats=[#c_literal{anno=LA,val=[]},AccVar],guard=[],
- body=[AccVar]}]
- end,
- Cs = case Pc of
- nomatch -> Cs0;
- _ ->
- Body = Lps ++ Nps ++ [#iset{var=AccVar,arg=Lc},Nc],
- [#iclause{anno=LAnno,
- pats=[ann_c_cons(LA,Pc,Tail),AccVar],
- guard=Guardc,
- body=Body}|Cs0]
- end,
- Fun = #ifun{anno=LAnno,id=[],vars=[Arg,AccVar],clauses=Cs,fc=Fc},
- {#iletrec{anno=LAnno,defs=[{{Name,2},Fun}],
- body=Gps ++ [#iapply{anno=LAnno,
- op=#c_var{anno=LA,name={Name,2}},
- args=[Gc,AccExpr]}]},
- [],St8};
-bc_tq1(Line, E, [{b_generate,Lg,P,G}|Qs0], AccExpr, St0) ->
- {Gs,Qs1} = splitwith(fun is_guard_test/1, Qs0),
+bc_tq1(Line, E, [#igen{anno=GAnno,acc_pat=AccPat,acc_guard=AccGuard,
+ skip_pat=SkipPat,tail=Tail,tail_pat=TailPat,
+ arg={Pre,Arg}}|Qs], Mc, St0) ->
{Name,St1} = new_fun_name("lbc", St0),
LA = lineno_anno(Line, St1),
- {AccVar,St2} = new_var(LA, St1),
- LAnno = #a{anno=LA},
- HeadBinPattern = pattern(P, St2),
- #c_binary{segments=Ps0} = HeadBinPattern,
- {Ps,Tail,St3} = append_tail_segment(Ps0, St2),
- {EPs,St4} = emasculate_segments(Ps, St3),
- Pattern = HeadBinPattern#c_binary{segments=Ps},
- EPattern = HeadBinPattern#c_binary{segments=EPs},
- {Arg,St5} = new_var(St4),
- NewMore = {call,Lg,{atom,Lg,Name},[{var,Lg,Tail#c_var.name},
- {var,Lg,AccVar#c_var.name}]},
- {Guardc,St6} = lc_guard_tests(Gs, St5), %These are always flat!
- {Bc,Bps,St7} = bc_tq1(Line, E, Qs1, AccVar, St6),
- {Nc,Nps,St8} = expr(NewMore, St7),
- {Gc,Gps,St9} = safe(G, St8), %Will be a function argument!
- Fc = function_clause([Arg,AccVar], LA, {Name,2}),
- Body = Bps ++ Nps ++ [#iset{var=AccVar,arg=Bc},Nc],
- {TailSegList,_,St} = append_tail_segment([], St9),
- Cs = [#iclause{anno=LAnno,
- pats=[Pattern,AccVar],
- guard=Guardc,
- body=Body},
- #iclause{anno=#a{anno=[compiler_generated|LA]},
- pats=[EPattern,AccVar],
- guard=[],
- body=Nps ++ [Nc]},
- #iclause{anno=LAnno,
- pats=[#c_binary{anno=LA,segments=TailSegList},AccVar],
- guard=[],
- body=[AccVar]}],
- Fun = #ifun{anno=LAnno,id=[],vars=[Arg,AccVar],clauses=Cs,fc=Fc},
- {#iletrec{anno=LAnno,defs=[{{Name,2},Fun}],
- body=Gps ++ [#iapply{anno=LAnno,
- op=#c_var{anno=LA,name={Name,2}},
- args=[Gc,AccExpr]}]},
- [],St};
-bc_tq1(Line, E, [Fil0|Qs0], AccVar, St0) ->
- %% Special case sequences guard tests.
- LA = lineno_anno(element(2, Fil0), St0),
LAnno = #a{anno=LA},
- case is_guard_test(Fil0) of
- true ->
- {Gs0,Qs1} = splitwith(fun is_guard_test/1, Qs0),
- {Bc,Bps,St1} = bc_tq1(Line, E, Qs1, AccVar, St0),
- {Gs,St} = lc_guard_tests([Fil0|Gs0], St1), %These are always flat!
- {#icase{anno=LAnno,
- args=[],
- clauses=[#iclause{anno=LAnno,
- pats=[],
- guard=Gs,body=Bps ++ [Bc]}],
- fc=#iclause{anno=LAnno#a{anno=[compiler_generated|LA]},
- pats=[],guard=[],body=[AccVar]}},
- [],St};
- false ->
- {Bc,Bps,St1} = bc_tq1(Line, E, Qs0, AccVar, St0),
- {Fpat,St2} = new_var(St1),
- Fc = fail_clause([Fpat], LA,
- c_tuple([#c_literal{val=case_clause},Fpat])),
- %% Do a novars little optimisation here.
- {Filc,Fps,St} = novars(Fil0, St2),
- {#icase{anno=LAnno,
- args=[Filc],
- clauses=[#iclause{anno=LAnno,
- pats=[#c_literal{anno=LA,val=true}],
- guard=[],
- body=Bps ++ [Bc]},
- #iclause{anno=LAnno#a{anno=[compiler_generated|LA]},
- pats=[#c_literal{anno=LA,val=false}],
- guard=[],
- body=[AccVar]}],
- fc=Fc},
- Fps,St}
- end;
+ {Vars=[_,AccVar],St2} = new_vars(LA, 2, St1),
+ F = #c_var{anno=LA,name={Name,2}},
+ Nc = #iapply{anno=GAnno,op=F,args=[Tail,AccVar]},
+ Fc = function_clause(Vars, LA, {Name,2}),
+ TailClause = #iclause{anno=LAnno,pats=[TailPat,AccVar],guard=[],
+ body=[AccVar]},
+ Cs0 = case {AccPat,AccGuard} of
+ {SkipPat,[]} ->
+ %% Skip and accumulator patterns are the same and there is
+ %% no guard, no need to generate a skip clause.
+ [TailClause];
+ _ ->
+ [#iclause{anno=#a{anno=[compiler_generated|LA]},
+ pats=[SkipPat,AccVar],guard=[],body=[Nc]},
+ TailClause]
+ end,
+ {Cs,St4} = case AccPat of
+ nomatch ->
+ %% The accumulator pattern never matches, no need
+ %% for an accumulator clause.
+ {Cs0,St2};
+ _ ->
+ {Bc,Bps,St3} = bc_tq1(Line, E, Qs, AccVar, St2),
+ Body = Bps ++ [#iset{var=AccVar,arg=Bc},Nc],
+ {[#iclause{anno=LAnno,
+ pats=[AccPat,AccVar],guard=AccGuard,
+ body=Body}|Cs0],
+ St3}
+ end,
+ Fun = #ifun{anno=LAnno,id=[],vars=Vars,clauses=Cs,fc=Fc},
+ {#iletrec{anno=LAnno#a{anno=[list_comprehension|LA]},defs=[{{Name,2},Fun}],
+ body=Pre ++ [#iapply{anno=LAnno,op=F,args=[Arg,Mc]}]},
+ [],St4};
+bc_tq1(Line, E, [#ifilter{}=Filter|Qs], Mc, St) ->
+ filter_tq(Line, E, Filter, Mc, St, Qs, fun bc_tq1/5);
bc_tq1(_, {bin,Bl,Elements}, [], AccVar, St0) ->
{E,Pre,St} = expr({bin,Bl,[{bin_element,Bl,
{var,Bl,AccVar#c_var.name},
@@ -1169,16 +1005,154 @@ bc_tq1(_, {bin,Bl,Elements}, [], AccVar, St0) ->
[binary,{unit,1}]}|Elements]}, St0),
#a{anno=A} = Anno0 = get_anno(E),
Anno = Anno0#a{anno=[compiler_generated,single_use|A]},
- %%Anno = Anno0#a{anno=[compiler_generated|A]},
{set_anno(E, Anno),Pre,St}.
+%% filter_tq(Line, Expr, Filter, Mc, State, [Qualifier], TqFun) ->
+%% {Case,[PreExpr],State}.
+%% Transform an intermediate comprehension filter to its intermediate case
+%% representation.
+
+filter_tq(Line, E, #ifilter{anno=#a{anno=LA}=LAnno,arg={Pre,Arg}},
+ Mc, St0, Qs, TqFun) ->
+ %% The filter is an expression, it is compiled to a case of degree 1 with
+ %% 3 clauses, one accumulating, one skipping and the final one throwing
+ %% {case_clause,Value} where Value is the result of the filter and is not a
+ %% boolean.
+ {Lc,Lps,St1} = TqFun(Line, E, Qs, Mc, St0),
+ {FailPat,St2} = new_var(St1),
+ Fc = fail_clause([FailPat], LA,
+ c_tuple([#c_literal{val=case_clause},FailPat])),
+ {#icase{anno=LAnno#a{anno=[list_comprehension|LA]},args=[Arg],
+ clauses=[#iclause{anno=LAnno,
+ pats=[#c_literal{val=true}],guard=[],
+ body=Lps ++ [Lc]},
+ #iclause{anno=LAnno#a{anno=[compiler_generated|LA]},
+ pats=[#c_literal{val=false}],guard=[],
+ body=[Mc]}],
+ fc=Fc},
+ Pre,St2};
+filter_tq(Line, E, #ifilter{anno=#a{anno=LA}=LAnno,arg=Guard},
+ Mc, St0, Qs, TqFun) when is_list(Guard) ->
+ %% Otherwise it is a guard, compiled to a case of degree 0 with 2 clauses,
+ %% the first matches if the guard succeeds and the comprehension continues
+ %% or the second one is selected and the current element is skipped.
+ {Lc,Lps,St1} = TqFun(Line, E, Qs, Mc, St0),
+ {#icase{anno=LAnno#a{anno=[list_comprehension|LA]},args=[],
+ clauses=[#iclause{anno=LAnno,pats=[],guard=Guard,body=Lps ++ [Lc]}],
+ fc=#iclause{anno=LAnno#a{anno=[compiler_generated|LA]},
+ pats=[],guard=[],body=[Mc]}},
+ [],St1}.
+
+%% preprocess_quals(Line, [Qualifier], State) -> {[Qualifier'],State}.
+%% Preprocess a list of Erlang qualifiers into its intermediate representation,
+%% represented as a list of #igen{} and #ifilter{} records. We recognise guard
+%% tests and try to fold them together and join to a preceding generators, this
+%% should give us better and more compact code.
+
+preprocess_quals(Line, Qs, St) ->
+ preprocess_quals(Line, Qs, St, []).
+
+preprocess_quals(Line, [Q|Qs0], St0, Acc) ->
+ case is_generator(Q) of
+ true ->
+ {Gs,Qs} = splitwith(fun is_guard_test/1, Qs0),
+ {Gen,St} = generator(Line, Q, Gs, St0),
+ preprocess_quals(Line, Qs, St, [Gen|Acc]);
+ false ->
+ LAnno = #a{anno=lineno_anno(get_anno(Q), St0)},
+ case is_guard_test(Q) of
+ true ->
+ %% When a filter is a guard test, its argument in the
+ %% #ifilter{} record is a list as returned by
+ %% lc_guard_tests/2.
+ {Gs,Qs} = splitwith(fun is_guard_test/1, Qs0),
+ {Cg,St} = lc_guard_tests([Q|Gs], St0),
+ Filter = #ifilter{anno=LAnno,arg=Cg},
+ preprocess_quals(Line, Qs, St, [Filter|Acc]);
+ false ->
+ %% Otherwise, it is a pair {Pre,Arg} as in a generator
+ %% input.
+ {Ce,Pre,St} = novars(Q, St0),
+ Filter = #ifilter{anno=LAnno,arg={Pre,Ce}},
+ preprocess_quals(Line, Qs0, St, [Filter|Acc])
+ end
+ end;
+preprocess_quals(_, [], St, Acc) ->
+ {reverse(Acc),St}.
+
+is_generator({generate,_,_,_}) -> true;
+is_generator({b_generate,_,_,_}) -> true;
+is_generator(_) -> false.
+
+%%
+%% Generators are abstracted as sextuplets:
+%% - acc_pat is the accumulator pattern, e.g. [Pat|Tail] for Pat <- Expr.
+%% - acc_guard is the list of guards immediately following the current
+%% generator in the qualifier list input.
+%% - skip_pat is the skip pattern, e.g. <<X,_:X,Tail/bitstring>> for
+%% <<X,1:X>> <= Expr.
+%% - tail is the variable used in AccPat and SkipPat bound to the rest of the
+%% generator input.
+%% - tail_pat is the tail pattern, respectively [] and <<_/bitstring>> for list
+%% and bit string generators.
+%% - arg is a pair {Pre,Arg} where Pre is the list of expressions to be
+%% inserted before the comprehension function and Arg is the expression
+%% that it should be passed.
+%%
+
+%% generator(Line, Generator, Guard, State) -> {Generator',State}.
+%% Transform a given generator into its #igen{} representation.
+
+generator(Line, {generate,Lg,P0,E}, Gs, St0) ->
+ LA = lineno_anno(Line, St0),
+ GA = lineno_anno(Lg, St0),
+ {Head,St1} = list_gen_pattern(P0, Line, St0),
+ {[Tail,Skip],St2} = new_vars(2, St1),
+ {Cg,St3} = lc_guard_tests(Gs, St2),
+ {AccPat,SkipPat} = case Head of
+ #c_var{} ->
+ %% If the generator pattern is a variable, the
+ %% pattern from the accumulator clause can be
+ %% reused in the skip one. lc_tq and bc_tq1 takes
+ %% care of dismissing the latter in that case.
+ Cons = ann_c_cons(LA, Head, Tail),
+ {Cons,Cons};
+ nomatch ->
+ %% If it never matches, there is no need for
+ %% an accumulator clause.
+ {nomatch,ann_c_cons(LA, Skip, Tail)};
+ _ ->
+ {ann_c_cons(LA, Head, Tail),
+ ann_c_cons(LA, Skip, Tail)}
+ end,
+ {Ce,Pre,St4} = safe(E, St3),
+ Gen = #igen{anno=#a{anno=GA},acc_pat=AccPat,acc_guard=Cg,skip_pat=SkipPat,
+ tail=Tail,tail_pat=#c_literal{anno=LA,val=[]},arg={Pre,Ce}},
+ {Gen,St4};
+generator(Line, {b_generate,Lg,P,E}, Gs, St0) ->
+ LA = lineno_anno(Line, St0),
+ GA = lineno_anno(Lg, St0),
+ Cp = #c_binary{segments=Segs} = pattern(P, St0),
+ %% The function append_tail_segment/2 keeps variable patterns as-is, making
+ %% it possible to have the same skip clause removal as with list generators.
+ {AccSegs,Tail,TailSeg,St1} = append_tail_segment(Segs, St0),
+ AccPat = Cp#c_binary{segments=AccSegs},
+ {Cg,St2} = lc_guard_tests(Gs, St1),
+ {SkipSegs,St3} = emasculate_segments(AccSegs, St2),
+ SkipPat = Cp#c_binary{segments=SkipSegs},
+ {Ce,Pre,St4} = safe(E, St3),
+ Gen = #igen{anno=#a{anno=GA},acc_pat=AccPat,acc_guard=Cg,skip_pat=SkipPat,
+ tail=Tail,tail_pat=#c_binary{anno=LA,segments=[TailSeg]},
+ arg={Pre,Ce}},
+ {Gen,St4}.
+
append_tail_segment(Segs, St0) ->
{Var,St} = new_var(St0),
Tail = #c_bitstr{val=Var,size=#c_literal{val=all},
unit=#c_literal{val=1},
type=#c_literal{val=binary},
flags=#c_literal{val=[unsigned,big]}},
- {Segs++[Tail],Var,St}.
+ {Segs++[Tail],Var,Tail,St}.
emasculate_segments(Segs, St) ->
emasculate_segments(Segs, St, []).
@@ -1189,7 +1163,7 @@ emasculate_segments([B|Rest], St0, Acc) ->
{Var,St1} = new_var(St0),
emasculate_segments(Rest, St1, [B#c_bitstr{val=Var}|Acc]);
emasculate_segments([], St, Acc) ->
- {lists:reverse(Acc),St}.
+ {reverse(Acc),St}.
lc_guard_tests([], St) -> {[],St};
lc_guard_tests(Gs0, St0) ->
@@ -1588,15 +1562,6 @@ pat_alias_list(_, _) -> throw(nomatch).
pattern_list(Ps, St) -> [pattern(P, St) || P <- Ps].
-%% first([A]) -> [A].
-%% last([A]) -> A.
-
-first([_]) -> [];
-first([H|T]) -> [H|first(T)].
-
-last([L]) -> L;
-last([_|T]) -> last(T).
-
%% make_vars([Name]) -> [{Var,Name}].
make_vars(Vs) -> [ #c_var{name=V} || V <- Vs ].
@@ -1679,13 +1644,13 @@ uclause(#iclause{anno=Anno,pats=Ps0,guard=G0,body=B0}, Pks, Ks0, St0) ->
uguard([], [], _, St) -> {[],St};
uguard(Pg, [], Ks, St) ->
%% No guard, so fold together equality tests.
- uguard(first(Pg), [last(Pg)], Ks, St);
+ uguard(droplast(Pg), [last(Pg)], Ks, St);
uguard(Pg, Gs0, Ks, St0) ->
%% Gs0 must contain at least one element here.
{Gs3,St5} = foldr(fun (T, {Gs1,St1}) ->
{L,St2} = new_var(St1),
{R,St3} = new_var(St2),
- {[#iset{var=L,arg=T}] ++ first(Gs1) ++
+ {[#iset{var=L,arg=T}] ++ droplast(Gs1) ++
[#iset{var=R,arg=last(Gs1)},
#icall{anno=#a{}, %Must have an #a{}
module=#c_literal{val=erlang},
@@ -2088,7 +2053,8 @@ cexpr(#ifun{anno=#a{us=Us0}=A0,name={named,Name},fc=#iclause{pats=Ps}}=Fun0,
RecVar = #c_var{name={Name,length(Ps)}},
Let = #c_let{vars=[#c_var{name=Name}],arg=RecVar,body=Body},
CFun1 = CFun0#c_fun{body=Let},
- Letrec = #c_letrec{defs=[{RecVar,CFun1}],
+ Letrec = #c_letrec{anno=A0#a.anno,
+ defs=[{RecVar,CFun1}],
body=RecVar},
{Letrec,[],Us1,St1}
end;
diff --git a/lib/compiler/src/v3_kernel.erl b/lib/compiler/src/v3_kernel.erl
index 9a2b1605ad..bc5ca0314a 100644
--- a/lib/compiler/src/v3_kernel.erl
+++ b/lib/compiler/src/v3_kernel.erl
@@ -81,7 +81,7 @@
-export([module/2,format_error/1]).
-import(lists, [map/2,foldl/3,foldr/3,mapfoldl/3,splitwith/2,member/2,
- keymember/3,keyfind/3,partition/2]).
+ keymember/3,keyfind/3,partition/2,droplast/1,last/1]).
-import(ordsets, [add_element/2,del_element/2,union/2,union/1,subtract/2]).
-import(cerl, [c_tuple/1]).
@@ -274,8 +274,7 @@ expr(#c_tuple{anno=A,es=Ces}, Sub, St0) ->
{#k_tuple{anno=A,es=Kes},Ep,St1};
expr(#c_map{anno=A,var=Var0,es=Ces}, Sub, St0) ->
{Var,[],St1} = expr(Var0, Sub, St0),
- {Kes,Ep,St2} = map_pairs(Ces, Sub, St1),
- {#k_map{anno=A,var=Var,es=Kes},Ep,St2};
+ map_split_pairs(A, Var, Ces, Sub, St1);
expr(#c_binary{anno=A,segments=Cv}, Sub, St0) ->
try atomic_bin(Cv, Sub, St0) of
{Kv,Ep,St1} ->
@@ -351,7 +350,7 @@ expr(#c_case{arg=Ca,clauses=Ccs}, Sub, St0) ->
{Kvs,Pv,St2} = match_vars(Ka, St1), %Must have variables here!
{Km,St3} = kmatch(Kvs, Ccs, Sub, St2),
Match = flatten_seq(build_match(Kvs, Km)),
- {last(Match),Pa ++ Pv ++ first(Match),St3};
+ {last(Match),Pa ++ Pv ++ droplast(Match),St3};
expr(#c_receive{anno=A,clauses=Ccs0,timeout=Ce,action=Ca}, Sub, St0) ->
{Ke,Pe,St1} = atomic(Ce, Sub, St0), %Force this to be atomic!
{Rvar,St2} = new_var(St1),
@@ -497,15 +496,71 @@ translate_match_fail_1(Anno, As, Sub, #kern{ff=FF}) ->
translate_fc(Args) ->
[#c_literal{val=function_clause},make_list(Args)].
-%% FIXME: Not completed
-map_pairs(Es, Sub, St) ->
- foldr(fun
- (#c_map_pair{op=#c_literal{val=Op},key=K0,val=V0}, {Kes,Esp,St0}) when
- Op =:= assoc; Op =:= exact -> %% assert Op
- {K,[],St1} = expr(K0, Sub, St0),
- {V,Ep,St2} = atomic(V0, Sub, St1),
- {[#k_map_pair{op=Op,key=K,val=V}|Kes],Ep ++ Esp,St2}
- end, {[],[],St}, Es).
+ %{Kes,Ep,St2} = map_pairs(Ces, Sub, St1),
+map_split_pairs(A, Var, Ces, Sub, St0) ->
+ %% two steps
+ %% 1. force variables
+ %% 2. remove multiples
+ Pairs0 = [{Op,K,V} || #c_map_pair{op=#c_literal{val=Op},key=K,val=V} <- Ces],
+ {Pairs,Esp,St1} = foldr(fun
+ ({Op,K0,V0}, {Ops,Espi,Sti0}) when Op =:= assoc; Op =:= exact ->
+ {K,[],Sti1} = expr(K0, Sub, Sti0),
+ {V,Ep,Sti2} = atomic(V0, Sub, Sti1),
+ {[{Op,K,V}|Ops],Ep ++ Espi,Sti2}
+ end, {[],[],St0}, Pairs0),
+
+ case map_group_pairs(Pairs) of
+ {Assoc,[]} ->
+ Kes = [#k_map_pair{key=K,val=V}||{_,{assoc,K,V}} <- Assoc],
+ {#k_map{anno=A,op=assoc,var=Var,es=Kes},Esp,St1};
+ {[],Exact} ->
+ Kes = [#k_map_pair{key=K,val=V}||{_,{exact,K,V}} <- Exact],
+ {#k_map{anno=A,op=exact,var=Var,es=Kes},Esp,St1};
+ {Assoc,Exact} ->
+ Kes1 = [#k_map_pair{key=K,val=V}||{_,{assoc,K,V}} <- Assoc],
+ {Mvar,Em,St2} = force_atomic(#k_map{anno=A,op=assoc,var=Var,es=Kes1},St1),
+ Kes2 = [#k_map_pair{key=K,val=V}||{_,{exact,K,V}} <- Exact],
+ {#k_map{anno=A,op=exact,var=Mvar,es=Kes2},Em ++ Esp,St2}
+
+ end.
+
+%% Group map by Assoc operations and Exact operations
+
+map_group_pairs(Es) ->
+ Groups = dict:to_list(map_group_pairs(Es,dict:new())),
+ partition(fun({_,{Op,_,_}}) -> Op =:= assoc end, Groups).
+
+map_group_pairs([{assoc,K,V}|Es0],Used0) ->
+ Used1 = case map_key_is_used(K,Used0) of
+ {ok, {assoc,_,_}} -> map_key_set_used(K,{assoc,K,V},Used0);
+ {ok, {exact,_,_}} -> map_key_set_used(K,{exact,K,V},Used0);
+ _ -> map_key_set_used(K,{assoc,K,V},Used0)
+ end,
+ map_group_pairs(Es0,Used1);
+map_group_pairs([{exact,K,V}|Es0],Used0) ->
+ Used1 = case map_key_is_used(K,Used0) of
+ {ok, {assoc,_,_}} -> map_key_set_used(K,{assoc,K,V},Used0);
+ {ok, {exact,_,_}} -> map_key_set_used(K,{exact,K,V},Used0);
+ _ -> map_key_set_used(K,{exact,K,V},Used0)
+ end,
+ map_group_pairs(Es0,Used1);
+map_group_pairs([],Used) ->
+ Used.
+
+map_key_set_used(K,How,Used) ->
+ dict:store(map_key_clean(K),How,Used).
+
+map_key_is_used(K,Used) ->
+ dict:find(map_key_clean(K),Used).
+
+%% Be explicit instead of using set_kanno(K,[])
+map_key_clean(#k_literal{val=V}) -> {k_literal,V};
+map_key_clean(#k_int{val=V}) -> {k_int,V};
+map_key_clean(#k_float{val=V}) -> {k_float,V};
+map_key_clean(#k_atom{val=V}) -> {k_atom,V};
+map_key_clean(#k_nil{}) -> k_nil;
+map_key_clean(#k_var{name=V}) -> {k_var,V}.
+
%% call_type(Module, Function, Arity) -> call | bif | apply | error.
%% Classify the call.
@@ -664,11 +719,11 @@ pattern(#c_tuple{anno=A,es=Ces}, Isub, Osub0, St0) ->
{#k_tuple{anno=A,es=Kes},Osub1,St1};
pattern(#c_map{anno=A,es=Ces}, Isub, Osub0, St0) ->
{Kes,Osub1,St1} = pattern_list(Ces, Isub, Osub0, St0),
- {#k_map{anno=A,es=Kes},Osub1,St1};
+ {#k_map{anno=A,op=exact,es=Kes},Osub1,St1};
pattern(#c_map_pair{op=#c_literal{val=exact},anno=A,key=Ck,val=Cv},Isub, Osub0, St0) ->
{Kk,Osub1,St1} = pattern(Ck, Isub, Osub0, St0),
{Kv,Osub2,St2} = pattern(Cv, Isub, Osub1, St1),
- {#k_map_pair{anno=A,op=exact,key=Kk,val=Kv},Osub2,St2};
+ {#k_map_pair{anno=A,key=Kk,val=Kv},Osub2,St2};
pattern(#c_binary{anno=A,segments=Cv}, Isub, Osub0, St0) ->
{Kv,Osub1,St1} = pattern_bin(Cv, Isub, Osub0, St0),
{#k_binary{anno=A,segs=Kv},Osub1,St1};
@@ -847,15 +902,6 @@ foldr2(Fun, Acc0, [E1|L1], [E2|L2]) ->
foldr2(Fun, Acc1, L1, L2);
foldr2(_, Acc, [], []) -> Acc.
-%% first([A]) -> [A].
-%% last([A]) -> A.
-
-last([L]) -> L;
-last([_|T]) -> last(T).
-
-first([_]) -> [];
-first([H|T]) -> [H|first(T)].
-
%% This code implements the algorithm for an optimizing compiler for
%% pattern matching given "The Implementation of Functional
%% Programming Languages" by Simon Peyton Jones. The code is much
@@ -1365,9 +1411,8 @@ new_clauses(Cs0, U, St) ->
[S,N|As];
#k_bin_int{next=N} ->
[N|As];
- #k_map{es=Es} ->
- Vals = [V ||
- #k_map_pair{op=exact,val=V} <- Es],
+ #k_map{op=exact,es=Es} ->
+ Vals = [V || #k_map_pair{val=V} <- Es],
Vals ++ As;
_Other ->
As
@@ -1467,9 +1512,9 @@ arg_val(Arg, C) ->
_ ->
{set_kanno(S, []),U,T,Fs}
end;
- #k_map{es=Es} ->
+ #k_map{op=exact,es=Es} ->
Keys = [begin
- #k_map_pair{op=exact,key=#k_literal{val=Key}} = Pair,
+ #k_map_pair{key=#k_literal{val=Key}} = Pair,
Key
end || Pair <- Es],
%% multiple keys may have the same name
@@ -1885,7 +1930,7 @@ pat_vars(#k_tuple{es=Es}) ->
pat_list_vars(Es);
pat_vars(#k_map{es=Es}) ->
pat_list_vars(Es);
-pat_vars(#k_map_pair{op=exact,val=V}) ->
+pat_vars(#k_map_pair{val=V}) ->
pat_vars(V).
pat_list_vars(Ps) ->
diff --git a/lib/compiler/src/v3_kernel.hrl b/lib/compiler/src/v3_kernel.hrl
index c7886a070d..ab66445f73 100644
--- a/lib/compiler/src/v3_kernel.hrl
+++ b/lib/compiler/src/v3_kernel.hrl
@@ -38,8 +38,8 @@
-record(k_nil, {anno=[]}).
-record(k_tuple, {anno=[],es}).
--record(k_map, {anno=[],var,es}).
--record(k_map_pair, {anno=[],op,key,val}).
+-record(k_map, {anno=[],var,op,es}).
+-record(k_map_pair, {anno=[],key,val}).
-record(k_cons, {anno=[],hd,tl}).
-record(k_binary, {anno=[],segs}).
-record(k_bin_seg, {anno=[],size,unit,type,flags,seg,next}).
diff --git a/lib/compiler/src/v3_kernel_pp.erl b/lib/compiler/src/v3_kernel_pp.erl
index edbd3f74f8..639c6737e2 100644
--- a/lib/compiler/src/v3_kernel_pp.erl
+++ b/lib/compiler/src/v3_kernel_pp.erl
@@ -110,15 +110,18 @@ format_1(#k_map{var=#k_var{}=Var,es=Es}, Ctxt) ->
" | ",format_1(Var, Ctxt),
$},$~
];
-format_1(#k_map{es=Es}, Ctxt) ->
- [$~,${,
+format_1(#k_map{op=assoc,es=Es}, Ctxt) ->
+ ["~{",
format_hseq(Es, ",", ctxt_bump_indent(Ctxt, 1), fun format/2),
- $},$~
+ "}~"
+ ];
+format_1(#k_map{op=exact,es=Es}, Ctxt) ->
+ ["::{",
+ format_hseq(Es, ",", ctxt_bump_indent(Ctxt, 1), fun format/2),
+ "}::"
];
-format_1(#k_map_pair{op=assoc,key=K,val=V}, Ctxt) ->
- ["~<",format(K, Ctxt),",",format(V, Ctxt),">"];
-format_1(#k_map_pair{op=exact,key=K,val=V}, Ctxt) ->
- ["::<",format(K, Ctxt),",",format(V, Ctxt),">"];
+format_1(#k_map_pair{key=K,val=V}, Ctxt) ->
+ ["<",format(K, Ctxt),",",format(V, Ctxt),">"];
format_1(#k_binary{segs=S}, Ctxt) ->
["#<",format(S, ctxt_bump_indent(Ctxt, 2)),">#"];
format_1(#k_bin_seg{next=Next}=S, Ctxt) ->
diff --git a/lib/compiler/src/v3_life.erl b/lib/compiler/src/v3_life.erl
index ae928e955c..c4f54a7970 100644
--- a/lib/compiler/src/v3_life.erl
+++ b/lib/compiler/src/v3_life.erl
@@ -367,12 +367,10 @@ literal(#k_bin_end{}, Ctxt) ->
{bin_end,Ctxt};
literal(#k_tuple{es=Es}, Ctxt) ->
{tuple,literal_list(Es, Ctxt)};
-literal(#k_map{var=Var,es=Es}, Ctxt) ->
- {map,literal(Var, Ctxt),literal_list(Es, Ctxt)};
-literal(#k_map_pair{op=assoc,key=K,val=V}, Ctxt) ->
- {map_pair_assoc,literal(K, Ctxt),literal(V, Ctxt)};
-literal(#k_map_pair{op=exact,key=K,val=V}, Ctxt) ->
- {map_pair_exact,literal(K, Ctxt),literal(V, Ctxt)};
+literal(#k_map{op=Op,var=Var,es=Es}, Ctxt) ->
+ {map,Op,literal(Var, Ctxt),literal_list(Es, Ctxt)};
+literal(#k_map_pair{key=K,val=V}, Ctxt) ->
+ {map_pair,literal(K, Ctxt),literal(V, Ctxt)};
literal(#k_literal{val=V}, _Ctxt) ->
{literal,V}.
@@ -402,8 +400,8 @@ literal2(#k_bin_end{}, Ctxt) ->
{bin_end,Ctxt};
literal2(#k_tuple{es=Es}, Ctxt) ->
{tuple,literal_list2(Es, Ctxt)};
-literal2(#k_map{es=Es}, Ctxt) ->
- {map,literal_list2(Es, Ctxt)};
+literal2(#k_map{op=Op,es=Es}, Ctxt) ->
+ {map,Op,literal_list2(Es, Ctxt)};
literal2(#k_map_pair{key=K,val=V}, Ctxt) ->
{map_pair,literal2(K, Ctxt),literal2(V, Ctxt)}.