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diff --git a/lib/compiler/src/v3_codegen.erl b/lib/compiler/src/v3_codegen.erl
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-%%
-%% %CopyrightBegin%
-%%
-%% Copyright Ericsson AB 1999-2018. All Rights Reserved.
-%%
-%% Licensed under the Apache License, Version 2.0 (the "License");
-%% you may not use this file except in compliance with the License.
-%% You may obtain a copy of the License at
-%%
-%% http://www.apache.org/licenses/LICENSE-2.0
-%%
-%% Unless required by applicable law or agreed to in writing, software
-%% distributed under the License is distributed on an "AS IS" BASIS,
-%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-%% See the License for the specific language governing permissions and
-%% limitations under the License.
-%%
-%% %CopyrightEnd%
-%%
-%% Purpose : Code generator for Beam.
-
--module(v3_codegen).
-
-%% The main interface.
--export([module/2]).
-
--import(lists, [member/2,keymember/3,keysort/2,keydelete/3,
- append/1,flatmap/2,filter/2,foldl/3,foldr/3,mapfoldl/3,
- sort/1,reverse/1,reverse/2,map/2]).
--import(ordsets, [add_element/2,intersection/2,union/2]).
-
--include("v3_kernel.hrl").
-
-%% These are not defined in v3_kernel.hrl.
-get_kanno(Kthing) -> element(2, Kthing).
-set_kanno(Kthing, Anno) -> setelement(2, Kthing, Anno).
-
-%% Main codegen structure.
--record(cg, {lcount=1, %Label counter
- bfail, %Fail label for BIFs
- break, %Break label
- recv, %Receive label
- is_top_block, %Boolean: top block or not
- functable=#{}, %Map of local functions: {Name,Arity}=>Label
- in_catch=false, %Inside a catch or not.
- need_frame, %Need a stack frame.
- ultimate_failure, %Label for ultimate match failure.
- ctx %Match context.
- }).
-
-%% Stack/register state record.
--record(sr, {reg=[], %Register table
- stk=[], %Stack table
- res=[]}). %Registers to reserve
-
-%% Internal records.
--record(cg_need_heap, {anno=[] :: term(),
- h=0 :: integer()}).
--record(cg_block, {anno=[] :: term(),
- es=[] :: [term()]}).
-
--type vdb_entry() :: {atom(),non_neg_integer(),non_neg_integer()}.
-
--record(l, {i=0 :: non_neg_integer(), %Op number
- vdb=[] :: [vdb_entry()], %Variable database
- a=[] :: [term()]}). %Core annotation
-
--spec module(#k_mdef{}, [compile:option()]) -> {'ok',beam_asm:module_code()}.
-
-module(#k_mdef{name=Mod,exports=Es,attributes=Attr,body=Forms}, _Opts) ->
- {Asm,St} = functions(Forms, {atom,Mod}),
- {ok,{Mod,Es,Attr,Asm,St#cg.lcount}}.
-
-functions(Forms, AtomMod) ->
- mapfoldl(fun (F, St) -> function(F, AtomMod, St) end, #cg{lcount=1}, Forms).
-
-function(#k_fdef{anno=#k{a=Anno},func=Name,arity=Arity,
- vars=As,body=Kb}, AtomMod, St0) ->
- try
- #k_match{} = Kb, %Assertion.
-
- %% Annotate kernel records with variable usage.
- Vdb0 = init_vars(As),
- {Body,_,Vdb} = body(Kb, 1, Vdb0),
-
- %% Generate the BEAM assembly code.
- {Asm,EntryLabel,St} = cg_fun(Body, As, Vdb, AtomMod,
- {Name,Arity}, Anno, St0),
- Func = {function,Name,Arity,EntryLabel,Asm},
- {Func,St}
- catch
- Class:Error:Stack ->
- io:fwrite("Function: ~w/~w\n", [Name,Arity]),
- erlang:raise(Class, Error, Stack)
- end.
-
-%% This pass creates beam format annotated with variable lifetime
-%% information. Each thing is given an index and for each variable we
-%% store the first and last index for its occurrence. The variable
-%% database, VDB, attached to each thing is only relevant internally
-%% for that thing.
-%%
-%% For nested things like matches the numbering continues locally and
-%% the VDB for that thing refers to the variable usage within that
-%% thing. Variables which live through a such a thing are internally
-%% given a very large last index. Internally the indexes continue
-%% after the index of that thing. This creates no problems as the
-%% internal variable info never escapes and externally we only see
-%% variable which are alive both before or after.
-%%
-%% This means that variables never "escape" from a thing and the only
-%% way to get values from a thing is to "return" them, with 'break' or
-%% 'return'. Externally these values become the return values of the
-%% thing. This is no real limitation as most nested things have
-%% multiple threads so working out a common best variable usage is
-%% difficult.
-
-%% body(Kbody, I, Vdb) -> {[Expr],MaxI,Vdb}.
-%% Handle a body.
-
-body(#k_seq{arg=Ke,body=Kb}, I, Vdb0) ->
- %%ok = io:fwrite("life ~w:~p~n", [?LINE,{Ke,I,Vdb0}]),
- A = get_kanno(Ke),
- Vdb1 = use_vars(union(A#k.us, A#k.ns), I, Vdb0),
- {Es,MaxI,Vdb2} = body(Kb, I+1, Vdb1),
- E = expr(Ke, I, Vdb2),
- {[E|Es],MaxI,Vdb2};
-body(Ke, I, Vdb0) ->
- %%ok = io:fwrite("life ~w:~p~n", [?LINE,{Ke,I,Vdb0}]),
- A = get_kanno(Ke),
- Vdb1 = use_vars(union(A#k.us, A#k.ns), I, Vdb0),
- E = expr(Ke, I, Vdb1),
- {[E],I,Vdb1}.
-
-%% expr(Kexpr, I, Vdb) -> Expr.
-
-expr(#k_test{anno=A}=Test, I, _Vdb) ->
- Test#k_test{anno=#l{i=I,a=A#k.a}};
-expr(#k_call{anno=A}=Call, I, _Vdb) ->
- Call#k_call{anno=#l{i=I,a=A#k.a}};
-expr(#k_enter{anno=A}=Enter, I, _Vdb) ->
- Enter#k_enter{anno=#l{i=I,a=A#k.a}};
-expr(#k_bif{anno=A}=Bif, I, _Vdb) ->
- Bif#k_bif{anno=#l{i=I,a=A#k.a}};
-expr(#k_match{anno=A,body=Kb,ret=Rs}, I, Vdb) ->
- %% Work out imported variables which need to be locked.
- Mdb = vdb_sub(I, I+1, Vdb),
- M = match(Kb, A#k.us, I+1, Mdb),
- L = #l{i=I,vdb=use_vars(A#k.us, I+1, Mdb),a=A#k.a},
- #k_match{anno=L,body=M,ret=Rs};
-expr(#k_guard_match{anno=A,body=Kb,ret=Rs}, I, Vdb) ->
- %% Work out imported variables which need to be locked.
- Mdb = vdb_sub(I, I+1, Vdb),
- M = match(Kb, A#k.us, I+1, Mdb),
- L = #l{i=I,vdb=use_vars(A#k.us, I+1, Mdb),a=A#k.a},
- #k_guard_match{anno=L,body=M,ret=Rs};
-expr(#k_protected{}=Protected, I, Vdb) ->
- protected(Protected, I, Vdb);
-expr(#k_try{anno=A,arg=Ka,vars=Vs,body=Kb,evars=Evs,handler=Kh}=Try, I, Vdb) ->
- %% Lock variables that are alive before the catch and used afterwards.
- %% Don't lock variables that are only used inside the try.
- Tdb0 = vdb_sub(I, I+1, Vdb),
- %% This is the tricky bit. Lock variables in Arg that are used in
- %% the body and handler. Add try tag 'variable'.
- Ab = get_kanno(Kb),
- Ah = get_kanno(Kh),
- Tdb1 = use_vars(union(Ab#k.us, Ah#k.us), I+3, Tdb0),
- Tdb2 = vdb_sub(I, I+2, Tdb1),
- Vnames = fun (Kvar) -> Kvar#k_var.name end, %Get the variable names
- {Aes,_,Adb} = body(Ka, I+2, add_var({catch_tag,I+1}, I+1, locked, Tdb2)),
- {Bes,_,Bdb} = body(Kb, I+4, new_vars(sort(map(Vnames, Vs)), I+3, Tdb2)),
- {Hes,_,Hdb} = body(Kh, I+4, new_vars(sort(map(Vnames, Evs)), I+3, Tdb2)),
- L = #l{i=I,vdb=Tdb1,a=A#k.a},
- Try#k_try{anno=L,
- arg=#cg_block{es=Aes,anno=#l{i=I+1,vdb=Adb,a=[]}},
- vars=Vs,body=#cg_block{es=Bes,anno=#l{i=I+3,vdb=Bdb,a=[]}},
- evars=Evs,handler=#cg_block{es=Hes,anno=#l{i=I+3,vdb=Hdb,a=[]}}};
-expr(#k_try_enter{anno=A,arg=Ka,vars=Vs,body=Kb,evars=Evs,handler=Kh}, I, Vdb) ->
- %% Lock variables that are alive before the catch and used afterwards.
- %% Don't lock variables that are only used inside the try.
- Tdb0 = vdb_sub(I, I+1, Vdb),
- %% This is the tricky bit. Lock variables in Arg that are used in
- %% the body and handler. Add try tag 'variable'.
- Ab = get_kanno(Kb),
- Ah = get_kanno(Kh),
- Tdb1 = use_vars(union(Ab#k.us, Ah#k.us), I+3, Tdb0),
- Tdb2 = vdb_sub(I, I+2, Tdb1),
- Vnames = fun (Kvar) -> Kvar#k_var.name end, %Get the variable names
- {Aes,_,Adb} = body(Ka, I+2, add_var({catch_tag,I+1}, I+1, 1000000, Tdb2)),
- {Bes,_,Bdb} = body(Kb, I+4, new_vars(sort(map(Vnames, Vs)), I+3, Tdb2)),
- {Hes,_,Hdb} = body(Kh, I+4, new_vars(sort(map(Vnames, Evs)), I+3, Tdb2)),
- L = #l{i=I,vdb=Tdb1,a=A#k.a},
- #k_try_enter{anno=L,
- arg=#cg_block{es=Aes,anno=#l{i=I+1,vdb=Adb,a=[]}},
- vars=Vs,body=#cg_block{es=Bes,anno=#l{i=I+3,vdb=Bdb,a=[]}},
- evars=Evs,handler=#cg_block{es=Hes,anno=#l{i=I+3,vdb=Hdb,a=[]}}};
-expr(#k_catch{anno=A,body=Kb}=Catch, I, Vdb) ->
- %% Lock variables that are alive before the catch and used afterwards.
- %% Don't lock variables that are only used inside the catch.
- %% Add catch tag 'variable'.
- Cdb0 = vdb_sub(I, I+1, Vdb),
- {Es,_,Cdb1} = body(Kb, I+1, add_var({catch_tag,I}, I, locked, Cdb0)),
- L = #l{i=I,vdb=Cdb1,a=A#k.a},
- Catch#k_catch{anno=L,body=#cg_block{es=Es}};
-expr(#k_receive{anno=A,var=V,body=Kb,action=Ka}=Recv, I, Vdb) ->
- %% Work out imported variables which need to be locked.
- Rdb = vdb_sub(I, I+1, Vdb),
- M = match(Kb, add_element(V#k_var.name, A#k.us), I+1,
- new_vars([V#k_var.name], I, Rdb)),
- {Tes,_,Adb} = body(Ka, I+1, Rdb),
- Le = #l{i=I,vdb=use_vars(A#k.us, I+1, Vdb),a=A#k.a},
- Recv#k_receive{anno=Le,body=M,
- action=#cg_block{anno=#l{i=I+1,vdb=Adb,a=[]},es=Tes}};
-expr(#k_receive_accept{anno=A}, I, _Vdb) ->
- #k_receive_accept{anno=#l{i=I,a=A#k.a}};
-expr(#k_receive_next{anno=A}, I, _Vdb) ->
- #k_receive_next{anno=#l{i=I,a=A#k.a}};
-expr(#k_put{anno=A}=Put, I, _Vdb) ->
- Put#k_put{anno=#l{i=I,a=A#k.a}};
-expr(#k_break{anno=A}=Break, I, _Vdb) ->
- Break#k_break{anno=#l{i=I,a=A#k.a}};
-expr(#k_guard_break{anno=A}=Break, I, _Vdb) ->
- Break#k_guard_break{anno=#l{i=I,a=A#k.a}};
-expr(#k_return{anno=A}=Ret, I, _Vdb) ->
- Ret#k_return{anno=#l{i=I,a=A#k.a}}.
-
-%% protected(Kprotected, I, Vdb) -> Protected.
-%% Only used in guards.
-
-protected(#k_protected{anno=A,arg=Ts}=Prot, I, Vdb) ->
- %% Lock variables that are alive before try and used afterwards.
- %% Don't lock variables that are only used inside the protected
- %% expression.
- Pdb0 = vdb_sub(I, I+1, Vdb),
- {T,MaxI,Pdb1} = body(Ts, I+1, Pdb0),
- Pdb2 = use_vars(A#k.ns, MaxI+1, Pdb1), %Save "return" values
- Prot#k_protected{arg=T,anno=#l{i=I,a=A#k.a,vdb=Pdb2}}.
-
-%% match(Kexpr, [LockVar], I, Vdb) -> Expr.
-%% Convert match tree to old format.
-
-match(#k_alt{anno=A,first=Kf,then=Kt}, Ls, I, Vdb0) ->
- Vdb1 = use_vars(union(A#k.us, Ls), I, Vdb0),
- F = match(Kf, Ls, I+1, Vdb1),
- T = match(Kt, Ls, I+1, Vdb1),
- #k_alt{anno=[],first=F,then=T};
-match(#k_select{anno=A,types=Kts}=Select, Ls, I, Vdb0) ->
- Vdb1 = use_vars(union(A#k.us, Ls), I, Vdb0),
- Ts = [type_clause(Tc, Ls, I+1, Vdb1) || Tc <- Kts],
- Select#k_select{anno=[],types=Ts};
-match(#k_guard{anno=A,clauses=Kcs}, Ls, I, Vdb0) ->
- Vdb1 = use_vars(union(A#k.us, Ls), I, Vdb0),
- Cs = [guard_clause(G, Ls, I+1, Vdb1) || G <- Kcs],
- #k_guard{anno=[],clauses=Cs};
-match(Other, Ls, I, Vdb0) ->
- Vdb1 = use_vars(Ls, I, Vdb0),
- {B,_,Vdb2} = body(Other, I+1, Vdb1),
- Le = #l{i=I,vdb=Vdb2,a=[]},
- #cg_block{anno=Le,es=B}.
-
-type_clause(#k_type_clause{anno=A,type=T,values=Kvs}, Ls, I, Vdb0) ->
- %%ok = io:format("life ~w: ~p~n", [?LINE,{T,Kvs}]),
- Vdb1 = use_vars(union(A#k.us, Ls), I+1, Vdb0),
- Vs = [val_clause(Vc, Ls, I+1, Vdb1) || Vc <- Kvs],
- #k_type_clause{anno=[],type=T,values=Vs}.
-
-val_clause(#k_val_clause{anno=A,val=V,body=Kb}, Ls0, I, Vdb0) ->
- New = (get_kanno(V))#k.ns,
- Bus = (get_kanno(Kb))#k.us,
- %%ok = io:format("Ls0 = ~p, Used=~p\n New=~p, Bus=~p\n", [Ls0,Used,New,Bus]),
- Ls1 = union(intersection(New, Bus), Ls0), %Lock for safety
- Vdb1 = use_vars(union(A#k.us, Ls1), I+1, new_vars(New, I, Vdb0)),
- B = match(Kb, Ls1, I+1, Vdb1),
- Le = #l{i=I,vdb=use_vars(Bus, I+1, Vdb1),a=A#k.a},
- #k_val_clause{anno=Le,val=V,body=B}.
-
-guard_clause(#k_guard_clause{anno=A,guard=Kg,body=Kb}, Ls, I, Vdb0) ->
- Vdb1 = use_vars(union(A#k.us, Ls), I+2, Vdb0),
- Gdb = vdb_sub(I+1, I+2, Vdb1),
- G = protected(Kg, I+1, Gdb),
- B = match(Kb, Ls, I+2, Vdb1),
- Le = #l{i=I,vdb=use_vars((get_kanno(Kg))#k.us, I+2, Vdb1),a=A#k.a},
- #k_guard_clause{anno=Le,guard=G,body=B}.
-
-
-%% Here follows the code generator pass.
-%%
-%% The following assumptions have been made:
-%%
-%% 1. Matches, i.e. things with {match,M,Ret} wrappers, only return
-%% values; no variables are exported. If the match would have returned
-%% extra variables then these have been transformed to multiple return
-%% values.
-%%
-%% 2. All BIF's called in guards are gc-safe so there is no need to
-%% put thing on the stack in the guard. While this would in principle
-%% work it would be difficult to keep track of the stack depth when
-%% trimming.
-%%
-%% The code generation uses variable lifetime information added by
-%% the previous pass to save variables, allocate registers and
-%% move registers to the stack when necessary.
-%%
-%% We try to use a consistent variable name scheme throughout. The
-%% StackReg record is always called Bef,Int<n>,Aft.
-
-%% cg_fun([Lkexpr], [HeadVar], Vdb, State) -> {[Ainstr],State}
-
-cg_fun(Les, Hvs, Vdb, AtomMod, NameArity, Anno, St0) ->
- {Fi,St1} = new_label(St0), %FuncInfo label
- {Fl,St2} = local_func_label(NameArity, St1),
-
- %%
- %% The pattern matching compiler (in v3_kernel) no longer
- %% provides its own catch-all clause, because the
- %% call to erlang:exit/1 caused problem when cases were
- %% used in guards. Therefore, there may be tests that
- %% cannot fail (providing that there is not a bug in a
- %% previous optimzation pass), but still need to provide
- %% a label (there are instructions, such as is_tuple/2,
- %% that do not allow {f,0}).
- %%
- %% We will generate an ultimate failure label and put it
- %% at the end of function, followed by an 'if_end' instruction.
- %% Note that and 'if_end' instruction does not need any
- %% live x registers, so it will always be safe to jump to
- %% it. (We never ever expect the jump to be taken, and in
- %% most functions there will never be any references to
- %% the label in the first place.)
- %%
-
- {UltimateMatchFail,St3} = new_label(St2),
-
- %% Create initial stack/register state, clear unused arguments.
- Bef = clear_dead(#sr{reg=foldl(fun (#k_var{name=V}, Reg) ->
- put_reg(V, Reg)
- end, [], Hvs),
- stk=[]}, 0, Vdb),
- {B,_Aft,St} = cg_list(Les, Vdb, Bef,
- St3#cg{bfail=0,
- ultimate_failure=UltimateMatchFail,
- is_top_block=true}),
- {Name,Arity} = NameArity,
- Asm = [{label,Fi},line(Anno),{func_info,AtomMod,{atom,Name},Arity},
- {label,Fl}|B++[{label,UltimateMatchFail},if_end]],
- {Asm,Fl,St}.
-
-%% cg(Lkexpr, Vdb, StackReg, State) -> {[Ainstr],StackReg,State}.
-%% Generate code for a kexpr.
-
-cg(#cg_block{anno=Le,es=Es}, Vdb, Bef, St) ->
- block_cg(Es, Le, Vdb, Bef, St);
-cg(#k_match{anno=Le,body=M,ret=Rs}, Vdb, Bef, St) ->
- match_cg(M, Rs, Le, Vdb, Bef, St);
-cg(#k_guard_match{anno=Le,body=M,ret=Rs}, Vdb, Bef, St) ->
- guard_match_cg(M, Rs, Le, Vdb, Bef, St);
-cg(#k_call{anno=Le,op=Func,args=As,ret=Rs}, Vdb, Bef, St) ->
- call_cg(Func, As, Rs, Le, Vdb, Bef, St);
-cg(#k_enter{anno=Le,op=Func,args=As}, Vdb, Bef, St) ->
- enter_cg(Func, As, Le, Vdb, Bef, St);
-cg(#k_bif{anno=Le}=Bif, Vdb, Bef, St) ->
- bif_cg(Bif, Le, Vdb, Bef, St);
-cg(#k_receive{anno=Le,timeout=Te,var=Rvar,body=Rm,action=Tes,ret=Rs},
- Vdb, Bef, St) ->
- recv_loop_cg(Te, Rvar, Rm, Tes, Rs, Le, Vdb, Bef, St);
-cg(#k_receive_next{anno=Le}, Vdb, Bef, St) ->
- recv_next_cg(Le, Vdb, Bef, St);
-cg(#k_receive_accept{}, _Vdb, Bef, St) ->
- {[remove_message],Bef,St};
-cg(#k_try{anno=Le,arg=Ta,vars=Vs,body=Tb,evars=Evs,handler=Th,ret=Rs},
- Vdb, Bef, St) ->
- try_cg(Ta, Vs, Tb, Evs, Th, Rs, Le, Vdb, Bef, St);
-cg(#k_try_enter{anno=Le,arg=Ta,vars=Vs,body=Tb,evars=Evs,handler=Th},
- Vdb, Bef, St) ->
- try_enter_cg(Ta, Vs, Tb, Evs, Th, Le, Vdb, Bef, St);
-cg(#k_catch{anno=Le,body=Cb,ret=[R]}, Vdb, Bef, St) ->
- catch_cg(Cb, R, Le, Vdb, Bef, St);
-cg(#k_put{anno=Le,arg=Con,ret=Var}, Vdb, Bef, St) ->
- put_cg(Var, Con, Le, Vdb, Bef, St);
-cg(#k_return{anno=Le,args=Rs}, Vdb, Bef, St) ->
- return_cg(Rs, Le, Vdb, Bef, St);
-cg(#k_break{anno=Le,args=Bs}, Vdb, Bef, St) ->
- break_cg(Bs, Le, Vdb, Bef, St);
-cg(#k_guard_break{anno=Le,args=Bs}, Vdb, Bef, St) ->
- guard_break_cg(Bs, Le, Vdb, Bef, St);
-cg(#cg_need_heap{h=H}, _Vdb, Bef, St) ->
- {[{test_heap,H,max_reg(Bef#sr.reg)}],Bef,St}.
-
-%% cg_list([Kexpr], FirstI, Vdb, StackReg, St) -> {[Ainstr],StackReg,St}.
-
-cg_list(Kes, Vdb, Bef, St0) ->
- {Keis,{Aft,St1}} =
- flatmapfoldl(fun (Ke, {Inta,Sta}) ->
- {Keis,Intb,Stb} = cg(Ke, Vdb, Inta, Sta),
- {Keis,{Intb,Stb}}
- end, {Bef,St0}, need_heap(Kes)),
- {Keis,Aft,St1}.
-
-%% need_heap([Lkexpr], I, St) -> [Lkexpr].
-%% Insert need_heap instructions in Kexpr list. Try to be smart and
-%% collect them together as much as possible.
-
-need_heap(Kes0) ->
- {Kes,H} = need_heap_0(reverse(Kes0), 0, []),
-
- %% Prepend need_heap if necessary.
- need_heap_need(H) ++ Kes.
-
-need_heap_0([Ke|Kes], H0, Acc) ->
- {Ns,H} = need_heap_1(Ke, H0),
- need_heap_0(Kes, H, [Ke|Ns]++Acc);
-need_heap_0([], H, Acc) ->
- {Acc,H}.
-
-need_heap_1(#k_put{arg=#k_binary{}}, H) ->
- {need_heap_need(H),0};
-need_heap_1(#k_put{arg=#k_map{}}, H) ->
- {need_heap_need(H),0};
-need_heap_1(#k_put{arg=Val}, H) ->
- %% Just pass through adding to needed heap.
- {[],H + case Val of
- #k_cons{} -> 2;
- #k_tuple{es=Es} -> 1 + length(Es);
- _Other -> 0
- end};
-need_heap_1(#k_bif{}=Bif, H) ->
- case is_gc_bif(Bif) of
- false ->
- {[],H};
- true ->
- {need_heap_need(H),0}
- end;
-need_heap_1(_Ke, H) ->
- %% Call or call-like instruction such as set_tuple_element/3.
- {need_heap_need(H),0}.
-
-need_heap_need(0) -> [];
-need_heap_need(H) -> [#cg_need_heap{h=H}].
-
-%% is_gc_bif(#k_bif{}) -> true|false.
-%% is_gc_bif(Name, Arity) -> true|false.
-%% Determines whether the BIF Name/Arity might do a GC.
-
-is_gc_bif(#k_bif{op=#k_remote{name=#k_atom{val=Name}},args=Args}) ->
- is_gc_bif(Name, length(Args));
-is_gc_bif(#k_bif{op=#k_internal{}}) ->
- true.
-
-is_gc_bif(hd, 1) -> false;
-is_gc_bif(tl, 1) -> false;
-is_gc_bif(self, 0) -> false;
-is_gc_bif(node, 0) -> false;
-is_gc_bif(node, 1) -> false;
-is_gc_bif(element, 2) -> false;
-is_gc_bif(get, 1) -> false;
-is_gc_bif(tuple_size, 1) -> false;
-is_gc_bif(map_get, 2) -> false;
-is_gc_bif(is_map_key, 2) -> false;
-is_gc_bif(Bif, Arity) ->
- not (erl_internal:bool_op(Bif, Arity) orelse
- erl_internal:new_type_test(Bif, Arity) orelse
- erl_internal:comp_op(Bif, Arity)).
-
-%% match_cg(Matc, [Ret], Le, Vdb, StackReg, State) ->
-%% {[Ainstr],StackReg,State}.
-%% Generate code for a match. First save all variables on the stack
-%% that are to survive after the match. We leave saved variables in
-%% their registers as they might actually be in the right place.
-
-match_cg(M, Rs, Le, Vdb, Bef, St0) ->
- I = Le#l.i,
- {Sis,Int0} = adjust_stack(Bef, I, I+1, Vdb),
- {B,St1} = new_label(St0),
- {Mis,Int1,St2} = match_cg(M, St1#cg.ultimate_failure,
- Int0, St1#cg{break=B}),
- %% Put return values in registers.
- Reg = load_vars(Rs, Int1#sr.reg),
- {Sis ++ Mis ++ [{label,B}],
- clear_dead(Int1#sr{reg=Reg}, I, Vdb),
- St2#cg{break=St1#cg.break}}.
-
-guard_match_cg(M, Rs, Le, Vdb, Bef, St0) ->
- I = Le#l.i,
- {B,St1} = new_label(St0),
- Fail = case St0 of
- #cg{bfail=0,ultimate_failure=Fail0} -> Fail0;
- #cg{bfail=Fail0} -> Fail0
- end,
- {Mis,Aft,St2} = match_cg(M, Fail, Bef, St1#cg{break=B}),
- %% Update the register descriptors for the return registers.
- Reg = guard_match_regs(Aft#sr.reg, Rs),
- {Mis ++ [{label,B}],
- clear_dead(Aft#sr{reg=Reg}, I, Vdb),
- St2#cg{break=St1#cg.break}}.
-
-guard_match_regs([{I,gbreakvar}|Rs], [#k_var{name=V}|Vs]) ->
- [{I,V}|guard_match_regs(Rs, Vs)];
-guard_match_regs([R|Rs], Vs) ->
- [R|guard_match_regs(Rs, Vs)];
-guard_match_regs([], []) -> [].
-
-
-%% match_cg(Match, Fail, StackReg, State) -> {[Ainstr],StackReg,State}.
-%% Generate code for a match tree. N.B. there is no need pass Vdb
-%% down as each level which uses this takes its own internal Vdb not
-%% the outer one.
-
-match_cg(#k_alt{first=F,then=S}, Fail, Bef, St0) ->
- {Tf,St1} = new_label(St0),
- {Fis,Faft,St2} = match_cg(F, Tf, Bef, St1),
- {Sis,Saft,St3} = match_cg(S, Fail, Bef, St2),
- Aft = sr_merge(Faft, Saft),
- {Fis ++ [{label,Tf}] ++ Sis,Aft,St3};
-match_cg(#k_select{var=#k_var{anno=Vanno,name=Vname}=V,types=Scs0}, Fail, Bef, St) ->
- ReuseForContext = member(reuse_for_context, Vanno) andalso
- find_reg(Vname, Bef#sr.reg) =/= error,
- Scs = case ReuseForContext of
- false -> Scs0;
- true -> bsm_rename_ctx(Scs0, Vname)
- end,
- match_fmf(fun (S, F, Sta) ->
- select_cg(S, V, F, Fail, Bef, Sta) end,
- Fail, St, Scs);
-match_cg(#k_guard{clauses=Gcs}, Fail, Bef, St) ->
- match_fmf(fun (G, F, Sta) -> guard_clause_cg(G, F, Bef, Sta) end,
- Fail, St, Gcs);
-match_cg(#cg_block{anno=Le,es=Es}, _Fail, Bef, St) ->
- %% Must clear registers and stack of dead variables.
- Int = clear_dead(Bef, Le#l.i, Le#l.vdb),
- block_cg(Es, Le, Int, St).
-
-%% bsm_rename_ctx([Clause], Var) -> [Clause]
-%% We know from an annotation that the register for a binary can
-%% be reused for the match context because the two are not truly
-%% alive at the same time (even though the life time information
-%% says so).
-%%
-%% The easiest way to have those variables share the same register is
-%% to rename the variable with the shortest life-span (the match
-%% context) to the variable for the binary (which can have a very
-%% long life-time because it is locked during matching). We KNOW that
-%% the match state variable will only be alive during the matching.
-%%
-%% We must also remove all information about the match context
-%% variable from all life-time information databases (Vdb).
-
-bsm_rename_ctx([#k_type_clause{type=k_binary,values=Vcs}=TC|Cs], New) ->
- [#k_val_clause{val=#k_binary{segs=#k_var{name=Old}}=Bin,
- body=Ke0}=VC0] = Vcs,
- Ke = bsm_rename_ctx(Ke0, Old, New, false),
- VC = VC0#k_val_clause{val=Bin#k_binary{segs=#k_var{name=New}},
- body=Ke},
- [TC#k_type_clause{values=[VC]}|bsm_rename_ctx(Cs, New)];
-bsm_rename_ctx([C|Cs], New) ->
- [C|bsm_rename_ctx(Cs, New)];
-bsm_rename_ctx([], _) -> [].
-
-%% bsm_rename_ctx(Ke, OldName, NewName, InProt) -> Ke'
-%% Rename and clear OldName from life-time information. We must
-%% recurse into any block contained in a protected, but it would
-%% only complicatate things to recurse into blocks not in a protected
-%% (the match context variable is not live inside them).
-
-bsm_rename_ctx(#k_select{var=#k_var{name=V},types=Cs0}=Sel,
- Old, New, InProt) ->
- Cs = bsm_rename_ctx_list(Cs0, Old, New, InProt),
- Sel#k_select{var=#k_var{name=bsm_rename_var(V, Old, New)},types=Cs};
-bsm_rename_ctx(#k_type_clause{values=Cs0}=TC, Old, New, InProt) ->
- Cs = bsm_rename_ctx_list(Cs0, Old, New, InProt),
- TC#k_type_clause{values=Cs};
-bsm_rename_ctx(#k_val_clause{body=Ke0}=VC, Old, New, InProt) ->
- Ke = bsm_rename_ctx(Ke0, Old, New, InProt),
- VC#k_val_clause{body=Ke};
-bsm_rename_ctx(#k_alt{first=F0,then=S0}=Alt, Old, New, InProt) ->
- F = bsm_rename_ctx(F0, Old, New, InProt),
- S = bsm_rename_ctx(S0, Old, New, InProt),
- Alt#k_alt{first=F,then=S};
-bsm_rename_ctx(#k_guard{clauses=Gcs0}=Guard, Old, New, InProt) ->
- Gcs = bsm_rename_ctx_list(Gcs0, Old, New, InProt),
- Guard#k_guard{clauses=Gcs};
-bsm_rename_ctx(#k_guard_clause{guard=G0,body=B0}=GC, Old, New, InProt) ->
- G = bsm_rename_ctx(G0, Old, New, InProt),
- B = bsm_rename_ctx(B0, Old, New, InProt),
- %% A guard clause may cause unsaved variables to be saved on the stack.
- %% Since the match state variable Old is an alias for New (uses the
- %% same register), it is neither in the stack nor register descriptor
- %% lists and we would crash when we didn't find it unless we remove
- %% it from the database.
- bsm_forget_var(GC#k_guard_clause{guard=G,body=B}, Old);
-bsm_rename_ctx(#k_protected{arg=Ts0}=Prot, Old, New, _InProt) ->
- InProt = true,
- Ts = bsm_rename_ctx_list(Ts0, Old, New, InProt),
- bsm_forget_var(Prot#k_protected{arg=Ts}, Old);
-bsm_rename_ctx(#k_guard_match{body=Ms0}=Match, Old, New, InProt) ->
- Ms = bsm_rename_ctx(Ms0, Old, New, InProt),
- Match#k_guard_match{body=Ms};
-bsm_rename_ctx(#k_test{}=Test, _, _, _) -> Test;
-bsm_rename_ctx(#k_bif{}=Bif, _, _, _) -> Bif;
-bsm_rename_ctx(#k_put{}=Put, _, _, _) -> Put;
-bsm_rename_ctx(#k_call{}=Call, _, _, _) -> Call;
-bsm_rename_ctx(#cg_block{}=Block, Old, _, false) ->
- %% This block is not inside a protected. The match context variable cannot
- %% possibly be live inside the block.
- bsm_forget_var(Block, Old);
-bsm_rename_ctx(#cg_block{es=Es0}=Block, Old, New, true) ->
- %% A block in a protected. We must recursively rename the variable
- %% inside the block.
- Es = bsm_rename_ctx_list(Es0, Old, New, true),
- bsm_forget_var(Block#cg_block{es=Es}, Old);
-bsm_rename_ctx(#k_guard_break{}=Break, Old, _New, _InProt) ->
- bsm_forget_var(Break, Old).
-
-bsm_rename_ctx_list([C|Cs], Old, New, InProt) ->
- [bsm_rename_ctx(C, Old, New, InProt)|
- bsm_rename_ctx_list(Cs, Old, New, InProt)];
-bsm_rename_ctx_list([], _, _, _) -> [].
-
-bsm_rename_var(Old, Old, New) -> New;
-bsm_rename_var(V, _, _) -> V.
-
-%% bsm_forget_var(#l{}, Variable) -> #l{}
-%% Remove a variable from the variable life-time database.
-
-bsm_forget_var(Ke, V) ->
- #l{vdb=Vdb} = L0 = get_kanno(Ke),
- L = L0#l{vdb=keydelete(V, 1, Vdb)},
- set_kanno(Ke, L).
-
-%% block_cg([Kexpr], Le, Vdb, StackReg, St) -> {[Ainstr],StackReg,St}.
-%% block_cg([Kexpr], Le, StackReg, St) -> {[Ainstr],StackReg,St}.
-
-block_cg(Es, Le, _Vdb, Bef, St) ->
- block_cg(Es, Le, Bef, St).
-
-block_cg(Es, Le, Bef, #cg{is_top_block=false}=St) ->
- cg_block(Es, Le#l.vdb, Bef, St);
-block_cg(Es, Le, Bef, #cg{is_top_block=true}=St0) ->
- %% No stack frame has been established yet. Do we need one?
- case need_stackframe(Es) of
- true ->
- %% We need a stack frame. Generate the code and add the
- %% code for creating and deallocating the stack frame.
- {Is0,Aft,St} = cg_block(Es, Le#l.vdb, Bef,
- St0#cg{is_top_block=false,need_frame=false}),
- Is = top_level_block(Is0, Aft, max_reg(Bef#sr.reg), St),
- {Is,Aft,St#cg{is_top_block=true}};
- false ->
- %% This sequence of instructions ending in a #k_match{} (a
- %% 'case' or 'if') in the Erlang code does not need a
- %% stack frame yet. Delay the creation (if a stack frame
- %% is needed at all, it will be created inside the
- %% #k_match{}).
- cg_list(Es, Le#l.vdb, Bef, St0)
- end.
-
-%% need_stackframe([Kexpr]) -> true|false.
-%% Does this list of instructions need a stack frame?
-%%
-%% A sequence of instructions that don't clobber the X registers
-%% followed by a single #k_match{} doesn't need a stack frame.
-
-need_stackframe([H|T]) ->
- case H of
- #k_bif{op=#k_internal{}} -> true;
- #k_put{arg=#k_binary{}} -> true;
- #k_bif{} -> need_stackframe(T);
- #k_put{} -> need_stackframe(T);
- #k_guard_match{} -> need_stackframe(T);
- #k_match{} when T =:= [] -> false;
- _ -> true
- end;
-need_stackframe([]) -> false.
-
-cg_block([], _Vdb, Bef, St0) ->
- {[],Bef,St0};
-cg_block(Kes0, Vdb, Bef, St0) ->
- {Kes2,Int1,St1} =
- case basic_block(Kes0) of
- {Kes1,LastI,Args,Rest} ->
- cg_basic_block(Kes1, LastI, Args, Vdb, Bef, St0);
- {Kes1,Rest} ->
- cg_list(Kes1, Vdb, Bef, St0)
- end,
- {Kes3,Int2,St2} = cg_block(Rest, Vdb, Int1, St1),
- {Kes2 ++ Kes3,Int2,St2}.
-
-basic_block(Kes) -> basic_block(Kes, []).
-
-basic_block([Ke|Kes], Acc) ->
- case collect_block(Ke) of
- include -> basic_block(Kes, [Ke|Acc]);
- {block_end,As} ->
- case Acc of
- [] ->
- %% If the basic block does not contain any #k_put{} instructions,
- %% it serves no useful purpose to do basic block optimizations.
- {[Ke],Kes};
- _ ->
- #l{i=I} = get_kanno(Ke),
- {reverse(Acc, [Ke]),I,As,Kes}
- end;
- no_block -> {reverse(Acc, [Ke]),Kes}
- end.
-
-collect_block(#k_put{arg=Arg}) ->
- %% #k_put{} instructions that may garbage collect are not allowed
- %% in basic blocks.
- case Arg of
- #k_binary{} -> no_block;
- #k_map{} -> no_block;
- _ -> include
- end;
-collect_block(#k_call{op=Func,args=As}) ->
- {block_end,As++func_vars(Func)};
-collect_block(#k_enter{op=Func,args=As}) ->
- {block_end,As++func_vars(Func)};
-collect_block(#k_return{args=Rs}) ->
- {block_end,Rs};
-collect_block(#k_break{args=Bs}) ->
- {block_end,Bs};
-collect_block(_) -> no_block.
-
-func_vars(#k_var{}=Var) ->
- [Var];
-func_vars(#k_remote{mod=M,name=F})
- when is_record(M, k_var); is_record(F, k_var) ->
- [M,F];
-func_vars(_) -> [].
-
-%% cg_basic_block([Kexpr], FirstI, LastI, Arguments, Vdb, StackReg, State) ->
-%% {[Ainstr],StackReg,State}.
-%%
-%% Do a specialized code generation for a basic block of #put{}
-%% instructions (that don't do any garbage collection) followed by a
-%% call, break, or return.
-%%
-%% 'Arguments' is a list of the variables that must be loaded into
-%% consecutive X registers before the last instruction in the block.
-%% The point of this specialized code generation is to try put the
-%% all of the variables in 'Arguments' into the correct X register
-%% to begin with, instead of putting them into the first available
-%% X register and having to move them to the correct X register
-%% later.
-%%
-%% To achieve that, we attempt to reserve the X registers that the
-%% variables in 'Arguments' will need to be in when the block ends.
-%%
-%% To make it more likely that reservations will be successful, we
-%% will try to save variables that need to be saved to the stack as
-%% early as possible (if an X register needed by a variable in
-%% Arguments is occupied by another variable, the value in the
-%% X register can be evicted if it is saved on the stack).
-%%
-%% We will take care not to increase the size of stack frame compared
-%% to what the standard code generator would have done (that is, to
-%% save all X registers at the last possible moment). We will do that
-%% by extending the stack frame to the minimal size needed to save
-%% all that needs to be saved using extend_stack/4, and use
-%% save_carefully/4 during code generation to only save the variables
-%% that can be saved without growing the stack frame.
-
-cg_basic_block(Kes, Lf, As, Vdb, Bef, St0) ->
- Int0 = reserve_arg_regs(As, Bef),
- Int = extend_stack(Int0, Lf, Lf+1, Vdb),
- {Keis,{Aft,St1}} =
- flatmapfoldl(fun(Ke, St) -> cg_basic_block(Ke, St, Lf, Vdb) end,
- {Int,St0}, need_heap(Kes)),
- {Keis,Aft,St1}.
-
-cg_basic_block(#cg_need_heap{}=Ke, {Bef,St0}, _Lf, Vdb) ->
- {Keis,Aft,St1} = cg(Ke, Vdb, Bef, St0),
- {Keis,{Aft,St1}};
-cg_basic_block(Ke, {Bef,St0}, Lf, Vdb) ->
- #l{i=I} = get_kanno(Ke),
-
- %% Save all we can to increase the possibility that reserving
- %% registers will succeed.
- {Sis,Int0} = save_carefully(Bef, I, Lf+1, Vdb),
- Int1 = reserve(Int0),
- {Keis,Aft,St1} = cg(Ke, Vdb, Int1, St0),
- {Sis ++ Keis,{Aft,St1}}.
-
-%% reserve_arg_regs([Argument], Bef) -> Aft.
-%% Try to reserve the X registers for all arguments. All registers
-%% that we wish to reserve will be saved in Bef#sr.res.
-
-reserve_arg_regs(As, Bef) ->
- Res = reserve_arg_regs_1(As, 0),
- reserve(Bef#sr{res=Res}).
-
-reserve_arg_regs_1([#k_var{name=V}|As], I) ->
- [{I,V}|reserve_arg_regs_1(As, I+1)];
-reserve_arg_regs_1([A|As], I) ->
- [{I,A}|reserve_arg_regs_1(As, I+1)];
-reserve_arg_regs_1([], _) -> [].
-
-%% reserve(Bef) -> Aft.
-%% Try to reserve more registers. The registers we wish to reserve
-%% are found in Bef#sr.res.
-
-reserve(#sr{reg=Regs,stk=Stk,res=Res}=Sr) ->
- Sr#sr{reg=reserve_1(Res, Regs, Stk)}.
-
-reserve_1([{I,V}|Rs], [free|Regs], Stk) ->
- [{reserved,I,V}|reserve_1(Rs, Regs, Stk)];
-reserve_1([{I,V}|Rs], [{I,V}|Regs], Stk) ->
- [{I,V}|reserve_1(Rs, Regs, Stk)];
-reserve_1([{I,V}|Rs], [{I,Var}|Regs], Stk) ->
- case on_stack(Var, Stk) of
- true -> [{reserved,I,V}|reserve_1(Rs, Regs, Stk)];
- false -> [{I,Var}|reserve_1(Rs, Regs, Stk)]
- end;
-reserve_1([{I,V}|Rs], [{reserved,I,_}|Regs], Stk) ->
- [{reserved,I,V}|reserve_1(Rs, Regs, Stk)];
-reserve_1([{I,V}|Rs], [], Stk) ->
- [{reserved,I,V}|reserve_1(Rs, [], Stk)];
-reserve_1([], Regs, _) -> Regs.
-
-%% extend_stack(Bef, FirstBefore, LastFrom, Vdb) -> Aft.
-%% Extend the stack enough to fit all variables alive past LastFrom
-%% and not already on the stack.
-
-extend_stack(#sr{stk=Stk0}=Bef, Fb, Lf, Vdb) ->
- Stk1 = clear_dead_stk(Stk0, Fb, Vdb),
- New = new_not_on_stack(Stk1, Fb, Lf, Vdb),
- Stk2 = foldl(fun ({V,_,_}, Stk) -> put_stack(V, Stk) end, Stk1, New),
- Stk = Stk0 ++ lists:duplicate(length(Stk2) - length(Stk0), free),
- Bef#sr{stk=Stk}.
-
-%% save_carefully(Bef, FirstBefore, LastFrom, Vdb) -> {[SaveVar],Aft}.
-%% Save variables which are used past current point and which are not
-%% already on the stack, but only if the variables can be saved without
-%% growing the stack frame.
-
-save_carefully(#sr{stk=Stk}=Bef, Fb, Lf, Vdb) ->
- New0 = new_not_on_stack(Stk, Fb, Lf, Vdb),
- New = keysort(2, New0),
- save_carefully_1(New, Bef, []).
-
-save_carefully_1([{V,_,_}|Vs], #sr{reg=Regs,stk=Stk0}=Bef, Acc) ->
- case put_stack_carefully(V, Stk0) of
- error ->
- {reverse(Acc),Bef};
- Stk1 ->
- SrcReg = fetch_reg(V, Regs),
- Move = {move,SrcReg,fetch_stack(V, Stk1)},
- {x,_} = SrcReg, %Assertion - must be X register.
- save_carefully_1(Vs, Bef#sr{stk=Stk1}, [Move|Acc])
- end;
-save_carefully_1([], Bef, Acc) ->
- {reverse(Acc),Bef}.
-
-%% top_level_block([Instruction], Bef, MaxRegs, St) -> [Instruction].
-%% For the top-level block, allocate a stack frame a necessary,
-%% adjust Y register numbering and instructions that return
-%% from the function.
-
-top_level_block(Keis, #sr{stk=[]}, _MaxRegs, #cg{need_frame=false}) ->
- Keis;
-top_level_block(Keis, Bef, MaxRegs, _St) ->
- %% This top block needs an allocate instruction before it, and a
- %% deallocate instruction before each return.
- FrameSz = length(Bef#sr.stk),
- MaxY = FrameSz-1,
- Keis1 = flatmap(fun ({call_only,Arity,Func}) ->
- [{call_last,Arity,Func,FrameSz}];
- ({call_ext_only,Arity,Func}) ->
- [{call_ext_last,Arity,Func,FrameSz}];
- ({apply_only,Arity}) ->
- [{apply_last,Arity,FrameSz}];
- (return) ->
- [{deallocate,FrameSz},return];
- (Tuple) when is_tuple(Tuple) ->
- [turn_yregs(Tuple, MaxY)];
- (Other) ->
- [Other]
- end, Keis),
- [{allocate_zero,FrameSz,MaxRegs}|Keis1].
-
-%% turn_yregs(Size, Tuple, MaxY) -> Tuple'
-%% Renumber y register so that {y,0} becomes {y,FrameSize-1},
-%% {y,FrameSize-1} becomes {y,0} and so on. This is to make nested
-%% catches work. The code generation algorithm gives a lower register
-%% number to the outer catch, which is wrong.
-
-turn_yregs({call,_,_}=I, _MaxY) -> I;
-turn_yregs({call_ext,_,_}=I, _MaxY) -> I;
-turn_yregs({jump,_}=I, _MaxY) -> I;
-turn_yregs({label,_}=I, _MaxY) -> I;
-turn_yregs({line,_}=I, _MaxY) -> I;
-turn_yregs({test_heap,_,_}=I, _MaxY) -> I;
-turn_yregs({bif,Op,F,A,B}, MaxY) ->
- {bif,Op,F,turn_yreg(A, MaxY),turn_yreg(B, MaxY)};
-turn_yregs({gc_bif,Op,F,Live,A,B}, MaxY) when is_integer(Live) ->
- {gc_bif,Op,F,Live,turn_yreg(A, MaxY),turn_yreg(B, MaxY)};
-turn_yregs({get_tuple_element,S,N,D}, MaxY) ->
- {get_tuple_element,turn_yreg(S, MaxY),N,turn_yreg(D, MaxY)};
-turn_yregs({put_tuple,Arity,D}, MaxY) ->
- {put_tuple,Arity,turn_yreg(D, MaxY)};
-turn_yregs({select_val,R,F,L}, MaxY) ->
- {select_val,turn_yreg(R, MaxY),F,L};
-turn_yregs({test,Op,F,L}, MaxY) ->
- {test,Op,F,turn_yreg(L, MaxY)};
-turn_yregs({test,Op,F,Live,A,B}, MaxY) when is_integer(Live) ->
- {test,Op,F,Live,turn_yreg(A, MaxY),turn_yreg(B, MaxY)};
-turn_yregs({Op,A}, MaxY) ->
- {Op,turn_yreg(A, MaxY)};
-turn_yregs({Op,A,B}, MaxY) ->
- {Op,turn_yreg(A, MaxY),turn_yreg(B, MaxY)};
-turn_yregs({Op,A,B,C}, MaxY) ->
- {Op,turn_yreg(A, MaxY),turn_yreg(B, MaxY),turn_yreg(C, MaxY)};
-turn_yregs(Tuple, MaxY) ->
- turn_yregs(tuple_size(Tuple), Tuple, MaxY).
-
-turn_yregs(1, Tp, _) ->
- Tp;
-turn_yregs(N, Tp, MaxY) ->
- E = turn_yreg(element(N, Tp), MaxY),
- turn_yregs(N-1, setelement(N, Tp, E), MaxY).
-
-turn_yreg({yy,YY}, MaxY) ->
- {y,MaxY-YY};
-turn_yreg({list,Ls},MaxY) ->
- {list,turn_yreg(Ls, MaxY)};
-turn_yreg([_|_]=Ts, MaxY) ->
- [turn_yreg(T, MaxY) || T <- Ts];
-turn_yreg(Other, _MaxY) ->
- Other.
-
-%% select_cg(Sclause, V, TypeFail, ValueFail, StackReg, State) ->
-%% {Is,StackReg,State}.
-%% Selecting type and value needs two failure labels, TypeFail is the
-%% label to jump to of the next type test when this type fails, and
-%% ValueFail is the label when this type is correct but the value is
-%% wrong. These are different as in the second case there is no need
-%% to try the next type, it will always fail.
-
-select_cg(#k_type_clause{type=Type,values=Vs}, Var, Tf, Vf, Bef, St) ->
- #k_var{name=V} = Var,
- select_cg(Type, Vs, V, Tf, Vf, Bef, St).
-
-select_cg(k_cons, [S], V, Tf, Vf, Bef, St) ->
- select_cons(S, V, Tf, Vf, Bef, St);
-select_cg(k_nil, [S], V, Tf, Vf, Bef, St) ->
- select_nil(S, V, Tf, Vf, Bef, St);
-select_cg(k_binary, [S], V, Tf, Vf, Bef, St) ->
- select_binary(S, V, Tf, Vf, Bef, St);
-select_cg(k_bin_seg, S, V, Tf, _Vf, Bef, St) ->
- select_bin_segs(S, V, Tf, Bef, St);
-select_cg(k_bin_int, S, V, Tf, _Vf, Bef, St) ->
- select_bin_segs(S, V, Tf, Bef, St);
-select_cg(k_bin_end, [S], V, Tf, _Vf, Bef, St) ->
- select_bin_end(S, V, Tf, Bef, St);
-select_cg(k_map, S, V, Tf, Vf, Bef, St) ->
- select_map(S, V, Tf, Vf, Bef, St);
-select_cg(k_literal, S, V, Tf, Vf, Bef, St) ->
- select_literal(S, V, Tf, Vf, Bef, St);
-select_cg(Type, Scs, V, Tf, Vf, Bef, St0) ->
- {Vis,{Aft,St1}} =
- mapfoldl(fun (S, {Int,Sta}) ->
- {Val,Is,Inta,Stb} = select_val(S, V, Vf, Bef, Sta),
- {{Is,[Val]},{sr_merge(Int, Inta),Stb}}
- end, {void,St0}, Scs),
- OptVls = combine(lists:sort(combine(Vis))),
- {Vls,Sis,St2} = select_labels(OptVls, St1, [], []),
- {select_val_cg(Type, fetch_var(V, Bef), Vls, Tf, Vf, Sis), Aft, St2}.
-
-select_val_cg(k_tuple, R, [Arity,{f,Lbl}], Tf, Vf, [{label,Lbl}|Sis]) ->
- [{test,is_tuple,{f,Tf},[R]},{test,test_arity,{f,Vf},[R,Arity]}|Sis];
-select_val_cg(k_tuple, R, Vls, Tf, Vf, Sis) ->
- [{test,is_tuple,{f,Tf},[R]},{select_tuple_arity,R,{f,Vf},{list,Vls}}|Sis];
-select_val_cg(Type, R, [Val, {f,Lbl}], Fail, Fail, [{label,Lbl}|Sis]) ->
- [{test,is_eq_exact,{f,Fail},[R,{type(Type),Val}]}|Sis];
-select_val_cg(Type, R, [Val, {f,Lbl}], Tf, Vf, [{label,Lbl}|Sis]) ->
- [{test,select_type_test(Type),{f,Tf},[R]},
- {test,is_eq_exact,{f,Vf},[R,{type(Type),Val}]}|Sis];
-select_val_cg(Type, R, Vls0, Tf, Vf, Sis) ->
- Vls1 = [case Value of
- {f,_Lbl} -> Value;
- _ -> {type(Type),Value}
- end || Value <- Vls0],
- [{test,select_type_test(Type),{f,Tf},[R]}, {select_val,R,{f,Vf},{list,Vls1}}|Sis].
-
-type(k_atom) -> atom;
-type(k_float) -> float;
-type(k_int) -> integer.
-
-select_type_test(k_int) -> is_integer;
-select_type_test(k_atom) -> is_atom;
-select_type_test(k_float) -> is_float.
-
-combine([{Is,Vs1}, {Is,Vs2}|Vis]) -> combine([{Is,Vs1 ++ Vs2}|Vis]);
-combine([V|Vis]) -> [V|combine(Vis)];
-combine([]) -> [].
-
-select_labels([{Is,Vs}|Vis], St0, Vls, Sis) ->
- {Lbl,St1} = new_label(St0),
- select_labels(Vis, St1, add_vls(Vs, Lbl, Vls), [[{label,Lbl}|Is]|Sis]);
-select_labels([], St, Vls, Sis) ->
- {Vls,append(Sis),St}.
-
-add_vls([V|Vs], Lbl, Acc) ->
- add_vls(Vs, Lbl, [V, {f,Lbl}|Acc]);
-add_vls([], _, Acc) -> Acc.
-
-select_literal(S, V, Tf, Vf, Bef, St) ->
- Reg = fetch_var(V, Bef),
- F = fun(ValClause, Fail, St0) ->
- {Val,Is,Aft,St1} = select_val(ValClause, V, Vf, Bef, St0),
- Test = {test,is_eq_exact,{f,Fail},[Reg,{literal,Val}]},
- {[Test|Is],Aft,St1}
- end,
- match_fmf(F, Tf, St, S).
-
-select_cons(#k_val_clause{val=#k_cons{hd=Hd,tl=Tl},body=B,anno=#l{i=I,vdb=Vdb}},
- V, Tf, Vf, Bef, St0) ->
- Es = [Hd,Tl],
- {Eis,Int,St1} = select_extract_cons(V, Es, I, Vdb, Bef, St0),
- {Bis,Aft,St2} = match_cg(B, Vf, Int, St1),
- {[{test,is_nonempty_list,{f,Tf},[fetch_var(V, Bef)]}] ++ Eis ++ Bis,Aft,St2}.
-
-select_nil(#k_val_clause{val=#k_nil{},body=B}, V, Tf, Vf, Bef, St0) ->
- {Bis,Aft,St1} = match_cg(B, Vf, Bef, St0),
- {[{test,is_nil,{f,Tf},[fetch_var(V, Bef)]}] ++ Bis,Aft,St1}.
-
-select_binary(#k_val_clause{val=#k_binary{segs=#k_var{name=V}},body=B,
- anno=#l{i=I,vdb=Vdb}}, V, Tf, Vf, Bef, St0) ->
- #cg{ctx=OldCtx} = St0,
- Int0 = clear_dead(Bef#sr{reg=Bef#sr.reg}, I, Vdb),
- {Bis0,Aft,St1} = match_cg(B, Vf, Int0, St0#cg{ctx=V}),
- CtxReg = fetch_var(V, Int0),
- Live = max_reg(Bef#sr.reg),
- Bis1 = [{test,bs_start_match2,{f,Tf},Live,[CtxReg,{context,V}],CtxReg},
- {bs_save2,CtxReg,{V,V}}|Bis0],
- Bis = finish_select_binary(Bis1),
- {Bis,Aft,St1#cg{ctx=OldCtx}};
-select_binary(#k_val_clause{val=#k_binary{segs=#k_var{name=Ivar}},body=B,
- anno=#l{i=I,vdb=Vdb}}, V, Tf, Vf, Bef, St0) ->
- #cg{ctx=OldCtx} = St0,
- Regs = put_reg(Ivar, Bef#sr.reg),
- Int0 = clear_dead(Bef#sr{reg=Regs}, I, Vdb),
- {Bis0,Aft,St1} = match_cg(B, Vf, Int0, St0#cg{ctx=Ivar}),
- CtxReg = fetch_var(Ivar, Int0),
- Live = max_reg(Bef#sr.reg),
- Bis1 = [{test,bs_start_match2,{f,Tf},Live,
- [fetch_var(V, Bef),{context,Ivar}],CtxReg},
- {bs_save2,CtxReg,{Ivar,Ivar}}|Bis0],
- Bis = finish_select_binary(Bis1),
- {Bis,Aft,St1#cg{ctx=OldCtx}}.
-
-finish_select_binary([{bs_save2,R,Point}=I,{bs_restore2,R,Point}|Is]) ->
- [I|finish_select_binary(Is)];
-finish_select_binary([{bs_save2,R,Point}=I,{test,is_eq_exact,_,_}=Test,
- {bs_restore2,R,Point}|Is]) ->
- [I,Test|finish_select_binary(Is)];
-finish_select_binary([{test,bs_match_string,F,[Ctx,BinList]}|Is])
- when is_list(BinList) ->
- I = {test,bs_match_string,F,[Ctx,list_to_bitstring(BinList)]},
- [I|finish_select_binary(Is)];
-finish_select_binary([I|Is]) ->
- [I|finish_select_binary(Is)];
-finish_select_binary([]) -> [].
-
-%% New instructions for selection of binary segments.
-
-select_bin_segs(Scs, Ivar, Tf, Bef, St) ->
- match_fmf(fun(S, Fail, Sta) ->
- select_bin_seg(S, Ivar, Fail, Bef, Sta) end,
- Tf, St, Scs).
-
-select_bin_seg(#k_val_clause{val=#k_bin_seg{size=Size,unit=U,type=T,
- seg=Seg,flags=Fs0,next=Next},
- body=B,
- anno=#l{i=I,vdb=Vdb,a=A}}, Ivar, Fail, Bef, St0) ->
- Ctx = St0#cg.ctx,
- Fs = [{anno,A}|Fs0],
- Es = case Next of
- [] -> [Seg];
- _ -> [Seg,Next]
- end,
- {Mis,Int,St1} = select_extract_bin(Es, Size, U, T, Fs, Fail,
- I, Vdb, Bef, Ctx, B, St0),
- {Bis,Aft,St2} = match_cg(B, Fail, Int, St1),
- CtxReg = fetch_var(Ctx, Bef),
- Is = if
- Mis =:= [] ->
- %% No bs_restore2 instruction needed if no match instructions.
- Bis;
- true ->
- [{bs_restore2,CtxReg,{Ctx,Ivar}}|Mis++Bis]
- end,
- {Is,Aft,St2};
-select_bin_seg(#k_val_clause{val=#k_bin_int{size=Sz,unit=U,flags=Fs,
- val=Val,next=Next},
- body=B,
- anno=#l{i=I,vdb=Vdb}}, Ivar, Fail, Bef, St0) ->
- Ctx = St0#cg.ctx,
- {Mis,Int,St1} = select_extract_int(Next, Val, Sz, U, Fs, Fail,
- I, Vdb, Bef, Ctx, St0),
- {Bis,Aft,St2} = match_cg(B, Fail, Int, St1),
- CtxReg = fetch_var(Ctx, Bef),
- Is = case Mis ++ Bis of
- [{test,bs_match_string,F,[OtherCtx,Bin1]},
- {bs_save2,OtherCtx,_},
- {bs_restore2,OtherCtx,_},
- {test,bs_match_string,F,[OtherCtx,Bin2]}|Is0] ->
- %% We used to do this optimization later, but it
- %% turns out that in huge functions with many
- %% bs_match_string instructions, it's a big win
- %% to do the combination now. To avoid copying the
- %% binary data again and again, we'll combine bitstrings
- %% in a list and convert all of it to a bitstring later.
- [{test,bs_match_string,F,[OtherCtx,[Bin1,Bin2]]}|Is0];
- Is0 ->
- Is0
- end,
- {[{bs_restore2,CtxReg,{Ctx,Ivar}}|Is],Aft,St2}.
-
-select_extract_int(#k_var{name=Tl}, Val, #k_int{val=Sz}, U, Fs, Vf,
- I, Vdb, Bef, Ctx, St) ->
- Bits = U*Sz,
- Bin = case member(big, Fs) of
- true ->
- <<Val:Bits>>;
- false ->
- true = member(little, Fs), %Assertion.
- <<Val:Bits/little>>
- end,
- Bits = bit_size(Bin), %Assertion.
- CtxReg = fetch_var(Ctx, Bef),
- Is = if
- Bits =:= 0 ->
- [{bs_save2,CtxReg,{Ctx,Tl}}];
- true ->
- [{test,bs_match_string,{f,Vf},[CtxReg,Bin]},
- {bs_save2,CtxReg,{Ctx,Tl}}]
- end,
- {Is,clear_dead(Bef, I, Vdb),St}.
-
-select_extract_bin([#k_var{name=Hd},#k_var{name=Tl}], Size0, Unit, Type, Flags, Vf,
- I, Vdb, Bef, Ctx, _Body, St) ->
- SizeReg = get_bin_size_reg(Size0, Bef),
- {Es,Aft} =
- case vdb_find(Hd, Vdb) of
- {_,_,Lhd} when Lhd =< I ->
- %% The extracted value will not be used.
- CtxReg = fetch_var(Ctx, Bef),
- Live = max_reg(Bef#sr.reg),
- Skip = build_skip_instr(Type, Vf, CtxReg, Live,
- SizeReg, Unit, Flags),
- {[Skip,{bs_save2,CtxReg,{Ctx,Tl}}],Bef};
- {_,_,_} ->
- Reg = put_reg(Hd, Bef#sr.reg),
- Int1 = Bef#sr{reg=Reg},
- Rhd = fetch_reg(Hd, Reg),
- CtxReg = fetch_reg(Ctx, Reg),
- Live = max_reg(Bef#sr.reg),
- {[build_bs_instr(Type, Vf, CtxReg, Live, SizeReg,
- Unit, Flags, Rhd),
- {bs_save2,CtxReg,{Ctx,Tl}}],Int1}
- end,
- {Es,clear_dead(Aft, I, Vdb),St};
-select_extract_bin([#k_var{name=Hd}], Size, Unit, binary, Flags, Vf,
- I, Vdb, Bef, Ctx, Body, St) ->
- %% Match the last segment of a binary. We KNOW that the size
- %% must be 'all'.
- #k_atom{val=all} = Size, %Assertion.
- {Es,Aft} =
- case vdb_find(Hd, Vdb) of
- {_,_,Lhd} when Lhd =< I ->
- %% The result will not be used. Furthermore, since we
- %% we are at the end of the binary, the position will
- %% not be used again; thus, it is safe to do a cheaper
- %% test of the unit.
- CtxReg = fetch_var(Ctx, Bef),
- {case Unit of
- 1 ->
- [];
- _ ->
- [{test,bs_test_unit,{f,Vf},[CtxReg,Unit]}]
- end,Bef};
- {_,_,_} ->
- case is_context_unused(Body) of
- false ->
- Reg = put_reg(Hd, Bef#sr.reg),
- Int1 = Bef#sr{reg=Reg},
- Rhd = fetch_reg(Hd, Reg),
- CtxReg = fetch_reg(Ctx, Reg),
- Name = bs_get_binary2,
- Live = max_reg(Bef#sr.reg),
- {[{test,Name,{f,Vf},Live,
- [CtxReg,atomic(Size),Unit,{field_flags,Flags}],Rhd}],
- Int1};
- true ->
- %% Since the matching context will not be used again,
- %% we can reuse its register. Reusing the register
- %% opens some interesting optimizations in the
- %% run-time system.
-
- Reg0 = Bef#sr.reg,
- CtxReg = fetch_reg(Ctx, Reg0),
- Reg = replace_reg_contents(Ctx, Hd, Reg0),
- Int1 = Bef#sr{reg=Reg},
- Name = bs_get_binary2,
- Live = max_reg(Int1#sr.reg),
- {[{test,Name,{f,Vf},Live,
- [CtxReg,atomic(Size),Unit,{field_flags,Flags}],CtxReg}],
- Int1}
- end
- end,
- {Es,clear_dead(Aft, I, Vdb),St}.
-
-%% is_context_unused(Ke) -> true | false
-%% Simple heurististic to determine whether the code that follows
-%% will use the current matching context again. (The liveness
-%% information is too conservative to be useful for this purpose.)
-%% 'true' means that the code that follows will definitely not use
-%% the context again (because it is a block, not guard or matching
-%% code); 'false' that we are not sure (there could be more
-%% matching).
-
-is_context_unused(#k_alt{then=Then}) ->
- %% #k_alt{} can be used for different purposes. If the Then part
- %% is a block, it means that matching has finished and is used for a guard
- %% to choose between the matched clauses.
- is_context_unused(Then);
-is_context_unused(#cg_block{}) ->
- true;
-is_context_unused(_) ->
- false.
-
-select_bin_end(#k_val_clause{val=#k_bin_end{},body=B}, Ivar, Tf, Bef, St0) ->
- Ctx = St0#cg.ctx,
- {Bis,Aft,St2} = match_cg(B, Tf, Bef, St0),
- CtxReg = fetch_var(Ctx, Bef),
- {[{bs_restore2,CtxReg,{Ctx,Ivar}},
- {test,bs_test_tail2,{f,Tf},[CtxReg,0]}|Bis],Aft,St2}.
-
-get_bin_size_reg(#k_var{name=V}, Bef) ->
- fetch_var(V, Bef);
-get_bin_size_reg(Literal, _Bef) ->
- atomic(Literal).
-
-build_bs_instr(Type, Vf, CtxReg, Live, SizeReg, Unit, Flags, Rhd) ->
- {Format,Name} = case Type of
- integer -> {plain,bs_get_integer2};
- float -> {plain,bs_get_float2};
- binary -> {plain,bs_get_binary2};
- utf8 -> {utf,bs_get_utf8};
- utf16 -> {utf,bs_get_utf16};
- utf32 -> {utf,bs_get_utf32}
- end,
- case Format of
- plain ->
- {test,Name,{f,Vf},Live,
- [CtxReg,SizeReg,Unit,{field_flags,Flags}],Rhd};
- utf ->
- {test,Name,{f,Vf},Live,
- [CtxReg,{field_flags,Flags}],Rhd}
- end.
-
-build_skip_instr(Type, Vf, CtxReg, Live, SizeReg, Unit, Flags) ->
- {Format,Name} = case Type of
- utf8 -> {utf,bs_skip_utf8};
- utf16 -> {utf,bs_skip_utf16};
- utf32 -> {utf,bs_skip_utf32};
- _ -> {plain,bs_skip_bits2}
- end,
- case Format of
- plain ->
- {test,Name,{f,Vf},[CtxReg,SizeReg,Unit,{field_flags,Flags}]};
- utf ->
- {test,Name,{f,Vf},[CtxReg,Live,{field_flags,Flags}]}
- end.
-
-select_val(#k_val_clause{val=#k_tuple{es=Es},body=B,anno=#l{i=I,vdb=Vdb}},
- V, Vf, Bef, St0) ->
- {Eis,Int,St1} = select_extract_tuple(V, Es, I, Vdb, Bef, St0),
- {Bis,Aft,St2} = match_cg(B, Vf, Int, St1),
- {length(Es),Eis ++ Bis,Aft,St2};
-select_val(#k_val_clause{val=Val0,body=B}, _V, Vf, Bef, St0) ->
- Val = case Val0 of
- #k_atom{val=Lit} -> Lit;
- #k_float{val=Lit} -> Lit;
- #k_int{val=Lit} -> Lit;
- #k_literal{val=Lit} -> Lit
- end,
- {Bis,Aft,St1} = match_cg(B, Vf, Bef, St0),
- {Val,Bis,Aft,St1}.
-
-%% select_extract_tuple(Src, [V], I, Vdb, StackReg, State) ->
-%% {[E],StackReg,State}.
-%% Extract tuple elements, but only if they do not immediately die.
-
-select_extract_tuple(Src, Vs, I, Vdb, Bef, St) ->
- F = fun (#k_var{name=V}, {Int0,Elem}) ->
- case vdb_find(V, Vdb) of
- {V,_,L} when L =< I -> {[], {Int0,Elem+1}};
- _Other ->
- Reg1 = put_reg(V, Int0#sr.reg),
- Int1 = Int0#sr{reg=Reg1},
- Rsrc = fetch_var(Src, Int1),
- {[{get_tuple_element,Rsrc,Elem,fetch_reg(V, Reg1)}],
- {Int1,Elem+1}}
- end
- end,
- {Es,{Aft,_}} = flatmapfoldl(F, {Bef,0}, Vs),
- {Es,Aft,St}.
-
-select_map(Scs, V, Tf, Vf, Bef, St0) ->
- Reg = fetch_var(V, Bef),
- {Is,Aft,St1} =
- match_fmf(fun(#k_val_clause{val=#k_map{op=exact,es=Es},
- body=B,anno=#l{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}.
-
-select_map_val(V, Es, B, Fail, I, Vdb, Bef, St0) ->
- {Eis,Int,St1} = select_extract_map(V, Es, Fail, I, Vdb, Bef, St0),
- {Bis,Aft,St2} = match_cg(B, Fail, Int, St1),
- {Eis++Bis,Aft,St2}.
-
-select_extract_map(_, [], _, _, _, Bef, St) -> {[],Bef,St};
-select_extract_map(Src, Vs, Fail, I, Vdb, Bef, St) ->
- %% First split the instruction flow
- %% We want one set of each
- %% 1) has_map_fields (no target registers)
- %% 2) get_map_elements (with target registers)
- %% Assume keys are term-sorted
- Rsrc = fetch_var(Src, Bef),
-
- {{HasKs,GetVs,HasVarKs,GetVarVs},Aft} =
- foldr(fun(#k_map_pair{key=#k_var{name=K},val=#k_var{name=V}},
- {{HasKsi,GetVsi,HasVarVsi,GetVarVsi},Int0}) ->
- case vdb_find(V, Vdb) of
- {V,_,L} when L =< I ->
- RK = fetch_var(K,Int0),
- {{HasKsi,GetVsi,[RK|HasVarVsi],GetVarVsi},Int0};
- _Other ->
- Reg1 = put_reg(V, Int0#sr.reg),
- Int1 = Int0#sr{reg=Reg1},
- RK = fetch_var(K,Int0),
- RV = fetch_reg(V,Reg1),
- {{HasKsi,GetVsi,HasVarVsi,[[RK,RV]|GetVarVsi]},Int1}
- end;
- (#k_map_pair{key=Key,val=#k_var{name=V}},
- {{HasKsi,GetVsi,HasVarVsi,GetVarVsi},Int0}) ->
- case vdb_find(V, Vdb) of
- {V,_,L} when L =< I ->
- {{[atomic(Key)|HasKsi],GetVsi,HasVarVsi,GetVarVsi},Int0};
- _Other ->
- Reg1 = put_reg(V, Int0#sr.reg),
- Int1 = Int0#sr{reg=Reg1},
- {{HasKsi,[atomic(Key),fetch_reg(V, Reg1)|GetVsi],
- HasVarVsi,GetVarVsi},Int1}
- end
- end, {{[],[],[],[]},Bef}, Vs),
-
- Code = [{test,has_map_fields,{f,Fail},Rsrc,{list,HasKs}} || HasKs =/= []] ++
- [{test,has_map_fields,{f,Fail},Rsrc,{list,[K]}} || K <- HasVarKs] ++
- [{get_map_elements, {f,Fail},Rsrc,{list,GetVs}} || GetVs =/= []] ++
- [{get_map_elements, {f,Fail},Rsrc,{list,[K,V]}} || [K,V] <- GetVarVs],
- {Code, Aft, St}.
-
-
-select_extract_cons(Src, [#k_var{name=Hd},#k_var{name=Tl}], I, Vdb, Bef, St) ->
- Rsrc = fetch_var(Src, Bef),
- Int = clear_dead(Bef, I, Vdb),
- {{_,_,Lhd},{_,_,Ltl}} = {vdb_find(Hd, Vdb),vdb_find(Tl, Vdb)},
- case {Lhd =< I, Ltl =< I} of
- {true,true} ->
- %% Both dead.
- {[],Bef,St};
- {true,false} ->
- %% Head dead.
- Reg0 = put_reg(Tl, Bef#sr.reg),
- Aft = Int#sr{reg=Reg0},
- Rtl = fetch_reg(Tl, Reg0),
- {[{get_tl,Rsrc,Rtl}],Aft,St};
- {false,true} ->
- %% Tail dead.
- Reg0 = put_reg(Hd, Bef#sr.reg),
- Aft = Int#sr{reg=Reg0},
- Rhd = fetch_reg(Hd, Reg0),
- {[{get_hd,Rsrc,Rhd}],Aft,St};
- {false,false} ->
- %% Both used.
- Reg0 = put_reg(Tl, put_reg(Hd, Bef#sr.reg)),
- Aft = Bef#sr{reg=Reg0},
- Rhd = fetch_reg(Hd, Reg0),
- Rtl = fetch_reg(Tl, Reg0),
- {[{get_hd,Rsrc,Rhd},{get_tl,Rsrc,Rtl}],Aft,St}
- end.
-
-guard_clause_cg(#k_guard_clause{anno=#l{vdb=Vdb},guard=G,body=B}, Fail, Bef, St0) ->
- {Gis,Int,St1} = guard_cg(G, Fail, Vdb, Bef, St0),
- {Bis,Aft,St} = match_cg(B, Fail, Int, St1),
- {Gis ++ Bis,Aft,St}.
-
-%% guard_cg(Guard, Fail, Vdb, StackReg, State) ->
-%% {[Ainstr],StackReg,State}.
-%% A guard is a boolean expression of tests. Tests return true or
-%% false. A fault in a test causes the test to return false. Tests
-%% never return the boolean, instead we generate jump code to go to
-%% the correct exit point. Primops and tests all go to the next
-%% instruction on success or jump to a failure label.
-
-guard_cg(#k_protected{arg=Ts,ret=Rs,anno=#l{vdb=Pdb}}, Fail, _Vdb, Bef, St) ->
- protected_cg(Ts, Rs, Fail, Pdb, Bef, St);
-guard_cg(#k_test{anno=#l{i=I},op=Test0,args=As,inverted=Inverted},
- Fail, Vdb, Bef, St0) ->
- #k_remote{mod=#k_atom{val=erlang},name=#k_atom{val=Test}} = Test0,
- case Inverted of
- false ->
- test_cg(Test, As, Fail, I, Vdb, Bef, St0);
- true ->
- {Psucc,St1} = new_label(St0),
- {Is,Aft,St2} = test_cg(Test, As, Psucc, I, Vdb, Bef, St1),
- {Is++[{jump,{f,Fail}},{label,Psucc}],Aft,St2}
- end;
-guard_cg(G, _Fail, Vdb, Bef, St) ->
- %%ok = io:fwrite("cg ~w: ~p~n", [?LINE,{G,Fail,Vdb,Bef}]),
- {Gis,Aft,St1} = cg(G, Vdb, Bef, St),
- %%ok = io:fwrite("cg ~w: ~p~n", [?LINE,{Aft}]),
- {Gis,Aft,St1}.
-
-%% guard_cg_list([Kexpr], Fail, I, Vdb, StackReg, St) ->
-%% {[Ainstr],StackReg,St}.
-
-guard_cg_list(Kes, Fail, Vdb, Bef, St0) ->
- {Keis,{Aft,St1}} =
- flatmapfoldl(fun (Ke, {Inta,Sta}) ->
- {Keis,Intb,Stb} =
- guard_cg(Ke, Fail, Vdb, Inta, Sta),
- {Keis,{Intb,Stb}}
- end, {Bef,St0}, need_heap(Kes)),
- {Keis,Aft,St1}.
-
-%% protected_cg([Kexpr], [Ret], Fail, I, Vdb, Bef, St) -> {[Ainstr],Aft,St}.
-%% Do a protected. Protecteds without return values are just done
-%% for effect, the return value is not checked, success passes on to
-%% the next instruction and failure jumps to Fail. If there are
-%% return values then these must be set to 'false' on failure,
-%% control always passes to the next instruction.
-
-protected_cg(Ts, [], Fail, Vdb, Bef, St0) ->
- %% Protect these calls, revert when done.
- {Tis,Aft,St1} = guard_cg_list(Ts, Fail, Vdb, Bef, St0#cg{bfail=Fail}),
- {Tis,Aft,St1#cg{bfail=St0#cg.bfail}};
-protected_cg(Ts, Rs, _Fail, Vdb, Bef, St0) ->
- {Pfail,St1} = new_label(St0),
- {Psucc,St2} = new_label(St1),
- {Tis,Aft,St3} = guard_cg_list(Ts, Pfail, Vdb, Bef,
- St2#cg{bfail=Pfail}),
- %%ok = io:fwrite("cg ~w: ~p~n", [?LINE,{Rs,I,Vdb,Aft}]),
- %% Set return values to false.
- Mis = [{move,{atom,false},fetch_var(V,Aft)}||#k_var{name=V} <- Rs],
- {Tis ++ [{jump,{f,Psucc}},
- {label,Pfail}] ++ Mis ++ [{label,Psucc}],
- Aft,St3#cg{bfail=St0#cg.bfail}}.
-
-%% test_cg(TestName, Args, Fail, I, Vdb, Bef, St) -> {[Ainstr],Aft,St}.
-%% Generate test instruction. Use explicit fail label here.
-
-test_cg(is_map, [A], Fail, I, Vdb, Bef, St) ->
- %% We must avoid creating code like this:
- %%
- %% move x(0) y(0)
- %% is_map Fail [x(0)]
- %% make_fun => x(0) %% Overwrite x(0)
- %% put_map_assoc y(0) ...
- %%
- %% The code is safe, but beam_validator does not understand that.
- %% Extending beam_validator to handle such (rare) code as the
- %% above would make it slower for all programs. Instead, change
- %% the code generator to always prefer the Y register for is_map()
- %% and put_map_assoc() instructions, ensuring that they use the
- %% same register.
- Arg = cg_reg_arg_prefer_y(A, Bef),
- Aft = clear_dead(Bef, I, Vdb),
- {[{test,is_map,{f,Fail},[Arg]}],Aft,St};
-test_cg(is_boolean, [#k_atom{val=Val}], Fail, I, Vdb, Bef, St) ->
- Aft = clear_dead(Bef, I, Vdb),
- Is = case is_boolean(Val) of
- true -> [];
- false -> [{jump,{f,Fail}}]
- end,
- {Is,Aft,St};
-test_cg(Test, As, Fail, I, Vdb, Bef, St) ->
- Args = cg_reg_args(As, Bef),
- Aft = clear_dead(Bef, I, Vdb),
- {[beam_utils:bif_to_test(Test, Args, {f,Fail})],Aft,St}.
-
-%% match_fmf(Fun, LastFail, State, [Clause]) -> {Is,Aft,State}.
-%% This is a special flatmapfoldl for match code gen where we
-%% generate a "failure" label for each clause. The last clause uses
-%% an externally generated failure label, LastFail. N.B. We do not
-%% know or care how the failure labels are used.
-
-match_fmf(F, LastFail, St, [H]) ->
- F(H, LastFail, St);
-match_fmf(F, LastFail, St0, [H|T]) ->
- {Fail,St1} = new_label(St0),
- {R,Aft1,St2} = F(H, Fail, St1),
- {Rs,Aft2,St3} = match_fmf(F, LastFail, St2, T),
- {R ++ [{label,Fail}] ++ Rs,sr_merge(Aft1, Aft2),St3}.
-
-%% call_cg(Func, [Arg], [Ret], Le, Vdb, StackReg, State) ->
-%% {[Ainstr],StackReg,State}.
-%% enter_cg(Func, [Arg], Le, Vdb, Bef, St) -> {[Ainstr],Aft,St}.
-%% Call and enter first put the arguments into registers and save any
-%% other registers, then clean up and compress the stack and set the
-%% frame size. Finally the actual call is made. Call then needs the
-%% return values filled in.
-
-call_cg(#k_var{}=Var, As, Rs, Le, Vdb, Bef, St0) ->
- {Sis,Int} = cg_setup_call(As++[Var], Bef, Le#l.i, Vdb),
- %% Put return values in registers.
- Reg = load_vars(Rs, clear_regs(Int#sr.reg)),
- %% Build complete code and final stack/register state.
- Arity = length(As),
- {Frees,Aft} = free_dead(clear_dead(Int#sr{reg=Reg}, Le#l.i, Vdb)),
- {Sis ++ Frees ++ [line(Le),{call_fun,Arity}],Aft,
- need_stack_frame(St0)};
-call_cg(#k_remote{mod=Mod,name=Name}, As, Rs, Le, Vdb, Bef, St0)
- when is_record(Mod, k_var); is_record(Name, k_var) ->
- {Sis,Int} = cg_setup_call(As++[Mod,Name], Bef, Le#l.i, Vdb),
- %% Put return values in registers.
- Reg = load_vars(Rs, clear_regs(Int#sr.reg)),
- %% Build complete code and final stack/register state.
- Arity = length(As),
- St = need_stack_frame(St0),
- %%{Call,St1} = build_call(Func, Arity, St0),
- {Frees,Aft} = free_dead(clear_dead(Int#sr{reg=Reg}, Le#l.i, Vdb)),
- {Sis ++ Frees ++ [line(Le),{apply,Arity}],Aft,St};
-call_cg(Func, As, Rs, Le, Vdb, Bef, St0) ->
- case St0 of
- #cg{bfail=Fail} when Fail =/= 0 ->
- %% Inside a guard. The only allowed function call is to
- %% erlang:error/1,2. We will generate the following code:
- %%
- %% move {atom,ok} DestReg
- %% jump FailureLabel
- #k_remote{mod=#k_atom{val=erlang},
- name=#k_atom{val=error}} = Func, %Assertion.
- [#k_var{name=DestVar}] = Rs,
- Int0 = clear_dead(Bef, Le#l.i, Vdb),
- Reg = put_reg(DestVar, Int0#sr.reg),
- Int = Int0#sr{reg=Reg},
- Dst = fetch_reg(DestVar, Reg),
- {[{move,{atom,ok},Dst},{jump,{f,Fail}}],
- clear_dead(Int, Le#l.i, Vdb),St0};
- #cg{} ->
- %% Ordinary function call in a function body.
- {Sis,Int} = cg_setup_call(As, Bef, Le#l.i, Vdb),
- %% Put return values in registers.
- Reg = load_vars(Rs, clear_regs(Int#sr.reg)),
- %% Build complete code and final stack/register state.
- Arity = length(As),
- {Call,St1} = build_call(Func, Arity, St0),
- {Frees,Aft} = free_dead(clear_dead(Int#sr{reg=Reg}, Le#l.i, Vdb)),
- {Sis ++ Frees ++ [line(Le)|Call],Aft,St1}
- end.
-
-build_call(#k_remote{mod=#k_atom{val=erlang},name=#k_atom{val='!'}}, 2, St0) ->
- {[send],need_stack_frame(St0)};
-build_call(#k_remote{mod=#k_atom{val=Mod},name=#k_atom{val=Name}}, Arity, St0) ->
- {[{call_ext,Arity,{extfunc,Mod,Name,Arity}}],need_stack_frame(St0)};
-build_call(#k_local{name=Name}, Arity, St0) when is_atom(Name) ->
- {Lbl,St1} = local_func_label(Name, Arity, need_stack_frame(St0)),
- {[{call,Arity,{f,Lbl}}],St1}.
-
-free_dead(#sr{stk=Stk0}=Aft) ->
- {Instr,Stk} = free_dead(Stk0, 0, [], []),
- {Instr,Aft#sr{stk=Stk}}.
-
-free_dead([dead|Stk], Y, Instr, StkAcc) ->
- %% Note: kill/1 is equivalent to init/1 (translated by beam_asm).
- %% We use kill/1 to help further optimisation passes.
- free_dead(Stk, Y+1, [{kill,{yy,Y}}|Instr], [free|StkAcc]);
-free_dead([Any|Stk], Y, Instr, StkAcc) ->
- free_dead(Stk, Y+1, Instr, [Any|StkAcc]);
-free_dead([], _, Instr, StkAcc) -> {Instr,reverse(StkAcc)}.
-
-enter_cg(#k_var{} = Var, As, Le, Vdb, Bef, St0) ->
- {Sis,Int} = cg_setup_call(As++[Var], Bef, Le#l.i, Vdb),
- %% Build complete code and final stack/register state.
- Arity = length(As),
- {Sis ++ [line(Le),{call_fun,Arity},return],
- clear_dead(Int#sr{reg=clear_regs(Int#sr.reg)}, Le#l.i, Vdb),
- need_stack_frame(St0)};
-enter_cg(#k_remote{mod=Mod,name=Name}, As, Le, Vdb, Bef, St0)
- when is_record(Mod, k_var); is_record(Name, k_var) ->
- {Sis,Int} = cg_setup_call(As++[Mod,Name], Bef, Le#l.i, Vdb),
- %% Build complete code and final stack/register state.
- Arity = length(As),
- St = need_stack_frame(St0),
- {Sis ++ [line(Le),{apply_only,Arity}],
- clear_dead(Int#sr{reg=clear_regs(Int#sr.reg)}, Le#l.i, Vdb),
- St};
-enter_cg(Func, As, Le, Vdb, Bef, St0) ->
- {Sis,Int} = cg_setup_call(As, Bef, Le#l.i, Vdb),
- %% Build complete code and final stack/register state.
- Arity = length(As),
- {Call,St1} = build_enter(Func, Arity, St0),
- Line = enter_line(Func, Arity, Le),
- {Sis ++ Line ++ Call,
- clear_dead(Int#sr{reg=clear_regs(Int#sr.reg)}, Le#l.i, Vdb),
- St1}.
-
-build_enter(#k_remote{mod=#k_atom{val=erlang},name=#k_atom{val='!'}}, 2, St0) ->
- {[send,return],need_stack_frame(St0)};
-build_enter(#k_remote{mod=#k_atom{val=Mod},name=#k_atom{val=Name}}, Arity, St0) ->
- St1 = case trap_bif(Mod, Name, Arity) of
- true -> need_stack_frame(St0);
- false -> St0
- end,
- {[{call_ext_only,Arity,{extfunc,Mod,Name,Arity}}],St1};
-build_enter(#k_local{name=Name}, Arity, St0) when is_atom(Name) ->
- {Lbl,St1} = local_func_label(Name, Arity, St0),
- {[{call_only,Arity,{f,Lbl}}],St1}.
-
-enter_line(#k_remote{mod=#k_atom{val=Mod},name=#k_atom{val=Name}}, Arity, Le) ->
- case erl_bifs:is_safe(Mod, Name, Arity) of
- false ->
- %% Tail-recursive call, possibly to a BIF.
- %% We'll need a line instruction in case the
- %% BIF call fails.
- [line(Le)];
- true ->
- %% Call to a safe BIF. Since it cannot fail,
- %% we don't need any line instruction here.
- []
- end;
-enter_line(_, _, _) ->
- %% Tail-recursive call to a local function. A line
- %% instruction will not be useful.
- [].
-
-%% local_func_label(Name, Arity, State) -> {Label,State'}
-%% local_func_label({Name,Arity}, State) -> {Label,State'}
-%% Get the function entry label for a local function.
-
-local_func_label(Name, Arity, St) ->
- local_func_label({Name,Arity}, St).
-
-local_func_label(Key, #cg{functable=Map}=St0) ->
- case Map of
- #{Key := Label} -> {Label,St0};
- _ ->
- {Label,St} = new_label(St0),
- {Label,St#cg{functable=Map#{Key => Label}}}
- end.
-
-%% need_stack_frame(State) -> State'
-%% Make a note in the state that this function will need a stack frame.
-
-need_stack_frame(#cg{need_frame=true}=St) -> St;
-need_stack_frame(St) -> St#cg{need_frame=true}.
-
-%% trap_bif(Mod, Name, Arity) -> true|false
-%% Trap bifs that need a stack frame.
-
-trap_bif(erlang, link, 1) -> true;
-trap_bif(erlang, unlink, 1) -> true;
-trap_bif(erlang, monitor_node, 2) -> true;
-trap_bif(erlang, group_leader, 2) -> true;
-trap_bif(erlang, exit, 2) -> true;
-trap_bif(_, _, _) -> false.
-
-%% bif_cg(#k_bif{}, Le, Vdb, StackReg, State) ->
-%% {[Ainstr],StackReg,State}.
-%% Generate code a BIF.
-
-bif_cg(#k_bif{op=#k_internal{name=Name},args=As,ret=Rs}, Le, Vdb, Bef, St) ->
- internal_cg(Name, As, Rs, Le, Vdb, Bef, St);
-bif_cg(#k_bif{op=#k_remote{mod=#k_atom{val=erlang},name=#k_atom{val=Name}},
- args=As,ret=Rs}, Le, Vdb, Bef, St) ->
- Ar = length(As),
- case is_gc_bif(Name, Ar) of
- false ->
- bif_cg(Name, As, Rs, Le, Vdb, Bef, St);
- true ->
- gc_bif_cg(Name, As, Rs, Le, Vdb, Bef, St)
- end.
-
-%% internal_cg(Bif, [Arg], [Ret], Le, Vdb, StackReg, State) ->
-%% {[Ainstr],StackReg,State}.
-
-internal_cg(bs_context_to_binary=Instr, [Src0], [], Le, Vdb, Bef, St0) ->
- [Src] = cg_reg_args([Src0], Bef),
- {[{Instr,Src}],clear_dead(Bef, Le#l.i, Vdb), St0};
-internal_cg(dsetelement, [Index0,Tuple0,New0], _Rs, Le, Vdb, Bef, St0) ->
- [New,Tuple,{integer,Index1}] = cg_reg_args([New0,Tuple0,Index0], Bef),
- Index = Index1-1,
- {[{set_tuple_element,New,Tuple,Index}],
- clear_dead(Bef, Le#l.i, Vdb), St0};
-internal_cg(make_fun, [Func0,Arity0|As], Rs, Le, Vdb, Bef, St0) ->
- %% This behaves more like a function call.
- #k_atom{val=Func} = Func0,
- #k_int{val=Arity} = Arity0,
- {Sis,Int} = cg_setup_call(As, Bef, Le#l.i, Vdb),
- Reg = load_vars(Rs, clear_regs(Int#sr.reg)),
- {FuncLbl,St1} = local_func_label(Func, Arity, St0),
- MakeFun = {make_fun2,{f,FuncLbl},0,0,length(As)},
- {Sis ++ [MakeFun],
- clear_dead(Int#sr{reg=Reg}, Le#l.i, Vdb),
- St1};
-internal_cg(bs_init_writable=I, As, Rs, Le, Vdb, Bef, St) ->
- %% This behaves like a function call.
- {Sis,Int} = cg_setup_call(As, Bef, Le#l.i, Vdb),
- Reg = load_vars(Rs, clear_regs(Int#sr.reg)),
- {Sis++[I],clear_dead(Int#sr{reg=Reg}, Le#l.i, Vdb),St};
-internal_cg(build_stacktrace=I, As, Rs, Le, Vdb, Bef, St) ->
- %% This behaves like a function call.
- {Sis,Int} = cg_setup_call(As, Bef, Le#l.i, Vdb),
- Reg = load_vars(Rs, clear_regs(Int#sr.reg)),
- {Sis++[I],clear_dead(Int#sr{reg=Reg}, Le#l.i, Vdb),St};
-internal_cg(raise, As, Rs, Le, Vdb, Bef, St) ->
- %% raise can be treated like a guard BIF.
- bif_cg(raise, As, Rs, Le, Vdb, Bef, St);
-internal_cg(guard_error, [ExitCall], _Rs, Le, Vdb, Bef, St) ->
- %% A call an exit BIF from inside a #k_guard_match{}.
- %% Generate a standard call, but leave the register descriptors
- %% alone, effectively pretending that there was no call.
- #k_call{op=#k_remote{mod=#k_atom{val=Mod},name=#k_atom{val=Name}},
- args=As} = ExitCall,
- Arity = length(As),
- {Ms,_} = cg_call_args(As, Bef, Le#l.i, Vdb),
- Call = {call_ext,Arity,{extfunc,Mod,Name,Arity}},
- Is = Ms++[line(Le),Call],
- {Is,Bef,St};
-internal_cg(raw_raise=I, As, Rs, Le, Vdb, Bef, St) ->
- %% This behaves like a function call.
- {Sis,Int} = cg_setup_call(As, Bef, Le#l.i, Vdb),
- Reg = load_vars(Rs, clear_regs(Int#sr.reg)),
- {Sis++[I],clear_dead(Int#sr{reg=Reg}, Le#l.i, Vdb),St}.
-
-%% bif_cg(Bif, [Arg], [Ret], Le, Vdb, StackReg, State) ->
-%% {[Ainstr],StackReg,State}.
-
-bif_cg(Bif, As, [#k_var{name=V}], Le, Vdb, Bef, St0) ->
- Ars = cg_reg_args(As, Bef),
-
- %% If we are inside a catch and in a body (not in guard) and the
- %% BIF may fail, we must save everything that will be alive after
- %% the catch (because the code after the code assumes that all
- %% variables that are live are stored on the stack).
- %%
- %% Currently, we are somewhat pessimistic in
- %% that we save any variable that will be live after this BIF call.
-
- MayFail = not erl_bifs:is_safe(erlang, Bif, length(As)),
- {Sis,Int0} =
- case MayFail of
- true ->
- maybe_adjust_stack(Bef, Le#l.i, Le#l.i+1, Vdb, St0);
- false ->
- {[],Bef}
- end,
- Int1 = clear_dead(Int0, Le#l.i, Vdb),
- Reg = put_reg(V, Int1#sr.reg),
- Int = Int1#sr{reg=Reg},
- Dst = fetch_reg(V, Reg),
- BifFail = {f,St0#cg.bfail},
- %% We need a line instructions for BIFs that may fail in a body.
- Line = case BifFail of
- {f,0} when MayFail ->
- [line(Le)];
- _ ->
- []
- end,
- {Sis++Line++[{bif,Bif,BifFail,Ars,Dst}],
- clear_dead(Int, Le#l.i, Vdb), St0}.
-
-
-%% gc_bif_cg(Bif, [Arg], [Ret], Le, Vdb, StackReg, State) ->
-%% {[Ainstr],StackReg,State}.
-
-gc_bif_cg(Bif, As, [#k_var{name=V}], Le, Vdb, Bef, St0) ->
- Ars = cg_reg_args(As, Bef),
-
- %% If we are inside a catch and in a body (not in guard) and the
- %% BIF may fail, we must save everything that will be alive after
- %% the catch (because the code after the code assumes that all
- %% variables that are live are stored on the stack).
- %%
- %% Currently, we are somewhat pessimistic in
- %% that we save any variable that will be live after this BIF call.
-
- {Sis,Int0} = maybe_adjust_stack(Bef, Le#l.i, Le#l.i+1, Vdb, St0),
-
- Int1 = clear_dead(Int0, Le#l.i, Vdb),
- Reg = put_reg(V, Int1#sr.reg),
- Int = Int1#sr{reg=Reg},
- Dst = fetch_reg(V, Reg),
- BifFail = {f,St0#cg.bfail},
- Line = case BifFail of
- {f,0} -> [line(Le)];
- {f,_} -> []
- end,
- {Sis++Line++[{gc_bif,Bif,BifFail,max_reg(Bef#sr.reg),Ars,Dst}],
- clear_dead(Int, Le#l.i, Vdb), St0}.
-
-%% recv_loop_cg(TimeOut, ReceiveVar, ReceiveMatch, TimeOutExprs,
-%% [Ret], Le, Vdb, Bef, St) -> {[Ainstr],Aft,St}.
-
-recv_loop_cg(Te, Rvar, Rm, Tes, Rs, Le, Vdb, Bef, St0) ->
- {Sis,Int0} = adjust_stack(Bef, Le#l.i, Le#l.i, Vdb),
- Int1 = Int0#sr{reg=clear_regs(Int0#sr.reg)},
- %% Get labels.
- {Rl,St1} = new_label(St0),
- {Tl,St2} = new_label(St1),
- {Bl,St3} = new_label(St2),
- St4 = St3#cg{break=Bl,recv=Rl}, %Set correct receive labels
- {Ris,Raft,St5} = cg_recv_mesg(Rvar, Rm, Tl, Int1, St4),
- {Wis,Taft,St6} = cg_recv_wait(Te, Tes, Le#l.i, Int1, St5),
- Int2 = sr_merge(Raft, Taft), %Merge stack/registers
- Reg = load_vars(Rs, Int2#sr.reg),
- {Sis ++ [line(Le)] ++ Ris ++ [{label,Tl}] ++ Wis ++ [{label,Bl}],
- clear_dead(Int2#sr{reg=Reg}, Le#l.i, Vdb),
- St6#cg{break=St0#cg.break,recv=St0#cg.recv}}.
-
-%% cg_recv_mesg( ) -> {[Ainstr],Aft,St}.
-
-cg_recv_mesg(#k_var{name=R}, Rm, Tl, Bef, St0) ->
- Int0 = Bef#sr{reg=put_reg(R, Bef#sr.reg)},
- Ret = fetch_reg(R, Int0#sr.reg),
- %% Int1 = clear_dead(Int0, I, Rm#l.vdb),
- Int1 = Int0,
- {Mis,Int2,St1} = match_cg(Rm, none, Int1, St0),
- {[{label,St1#cg.recv},{loop_rec,{f,Tl},Ret}|Mis],Int2,St1}.
-
-%% cg_recv_wait(Te, Tes, I, Vdb, Int2, St3) -> {[Ainstr],Aft,St}.
-
-cg_recv_wait(#k_atom{val=infinity}, #cg_block{anno=Le,es=Tes}, I, Bef, St0) ->
- %% We know that the 'after' body will never be executed.
- %% But to keep the stack and register information up to date,
- %% we will generate the code for the 'after' body, and then discard it.
- Int1 = clear_dead(Bef, I, Le#l.vdb),
- {_,Int2,St1} = cg_block(Tes, Le#l.vdb,
- Int1#sr{reg=clear_regs(Int1#sr.reg)}, St0),
- {[{wait,{f,St1#cg.recv}}],Int2,St1};
-cg_recv_wait(#k_int{val=0}, #cg_block{anno=Le,es=Tes}, _I, Bef, St0) ->
- {Tis,Int,St1} = cg_block(Tes, Le#l.vdb, Bef, St0),
- {[timeout|Tis],Int,St1};
-cg_recv_wait(Te, #cg_block{anno=Le,es=Tes}, I, Bef, St0) ->
- Reg = cg_reg_arg(Te, Bef),
- %% Must have empty registers here! Bug if anything in registers.
- Int0 = clear_dead(Bef, I, Le#l.vdb),
- {Tis,Int,St1} = cg_block(Tes, Le#l.vdb,
- Int0#sr{reg=clear_regs(Int0#sr.reg)}, St0),
- {[{wait_timeout,{f,St1#cg.recv},Reg},timeout] ++ Tis,Int,St1}.
-
-%% recv_next_cg(Le, Vdb, StackReg, St) -> {[Ainstr],StackReg,St}.
-%% Use adjust stack to clear stack, but only need it for Aft.
-
-recv_next_cg(Le, Vdb, Bef, St) ->
- {Sis,Aft} = adjust_stack(Bef, Le#l.i, Le#l.i+1, Vdb),
- {[{loop_rec_end,{f,St#cg.recv}}] ++ Sis,Aft,St}. %Joke
-
-%% try_cg(TryBlock, [BodyVar], TryBody, [ExcpVar], TryHandler, [Ret],
-%% Le, Vdb, StackReg, St) -> {[Ainstr],StackReg,St}.
-
-try_cg(Ta, Vs, Tb, Evs, Th, Rs, Le, Vdb, Bef, St0) ->
- {B,St1} = new_label(St0), %Body label
- {H,St2} = new_label(St1), %Handler label
- {E,St3} = new_label(St2), %End label
- #l{i=TryTag} = get_kanno(Ta),
- Int1 = Bef#sr{stk=put_catch(TryTag, Bef#sr.stk)},
- TryReg = fetch_stack({catch_tag,TryTag}, Int1#sr.stk),
- {Ais,Int2,St4} = cg(Ta, Vdb, Int1, St3#cg{break=B,in_catch=true}),
- Int3 = Int2#sr{stk=drop_catch(TryTag, Int2#sr.stk)},
- St5 = St4#cg{break=E,in_catch=St3#cg.in_catch},
- {Bis,Baft,St6} = cg(Tb, Vdb, Int3#sr{reg=load_vars(Vs, Int3#sr.reg)}, St5),
- {His,Haft,St7} = cg(Th, Vdb, Int3#sr{reg=load_vars(Evs, Int3#sr.reg)}, St6),
- Int4 = sr_merge(Baft, Haft), %Merge stack/registers
- Aft = Int4#sr{reg=load_vars(Rs, Int4#sr.reg)},
- {[{'try',TryReg,{f,H}}] ++ Ais ++
- [{label,B},{try_end,TryReg}] ++ Bis ++
- [{label,H},{try_case,TryReg}] ++ His ++
- [{label,E}],
- clear_dead(Aft, Le#l.i, Vdb),
- St7#cg{break=St0#cg.break}}.
-
-try_enter_cg(Ta, Vs, Tb, Evs, Th, Le, Vdb, Bef, St0) ->
- {B,St1} = new_label(St0), %Body label
- {H,St2} = new_label(St1), %Handler label
- #l{i=TryTag} = get_kanno(Ta),
- Int1 = Bef#sr{stk=put_catch(TryTag, Bef#sr.stk)},
- TryReg = fetch_stack({catch_tag,TryTag}, Int1#sr.stk),
- {Ais,Int2,St3} = cg(Ta, Vdb, Int1, St2#cg{break=B,in_catch=true}),
- Int3 = Int2#sr{stk=drop_catch(TryTag, Int2#sr.stk)},
- St4 = St3#cg{in_catch=St2#cg.in_catch},
- {Bis,Baft,St5} = cg(Tb, Vdb, Int3#sr{reg=load_vars(Vs, Int3#sr.reg)}, St4),
- {His,Haft,St6} = cg(Th, Vdb, Int3#sr{reg=load_vars(Evs, Int3#sr.reg)}, St5),
- Int4 = sr_merge(Baft, Haft), %Merge stack/registers
- Aft = Int4,
- {[{'try',TryReg,{f,H}}] ++ Ais ++
- [{label,B},{try_end,TryReg}] ++ Bis ++
- [{label,H},{try_case,TryReg}] ++ His,
- clear_dead(Aft, Le#l.i, Vdb),
- St6#cg{break=St0#cg.break}}.
-
-%% catch_cg(CatchBlock, Ret, Le, Vdb, Bef, St) -> {[Ainstr],Aft,St}.
-
-catch_cg(#cg_block{es=C}, #k_var{name=R}, Le, Vdb, Bef, St0) ->
- {B,St1} = new_label(St0),
- CatchTag = Le#l.i,
- Int1 = Bef#sr{stk=put_catch(CatchTag, Bef#sr.stk)},
- CatchReg = fetch_stack({catch_tag,CatchTag}, Int1#sr.stk),
- {Cis,Int2,St2} = cg_block(C, Le#l.vdb, Int1,
- St1#cg{break=B,in_catch=true}),
- [] = Int2#sr.reg, %Assertion.
- Aft = Int2#sr{reg=[{0,R}],stk=drop_catch(CatchTag, Int2#sr.stk)},
- {[{'catch',CatchReg,{f,B}}] ++ Cis ++
- [{label,B},{catch_end,CatchReg}],
- clear_dead(Aft, Le#l.i, Vdb),
- St2#cg{break=St1#cg.break,in_catch=St1#cg.in_catch}}.
-
-%% put_cg([Var], Constr, Le, Vdb, Bef, St) -> {[Ainstr],Aft,St}.
-%% We have to be careful how a 'put' works. First the structure is
-%% built, then it is filled and finally things can be cleared. The
-%% annotation must reflect this and make sure that the return
-%% variable is allocated first.
-%%
-%% put_list and put_map are atomic instructions, both of
-%% which can safely resuse one of the source registers as target.
-
-put_cg([#k_var{name=R}], #k_cons{hd=Hd,tl=Tl}, Le, Vdb, Bef, St) ->
- [S1,S2] = cg_reg_args([Hd,Tl], Bef),
- Int0 = clear_dead(Bef, Le#l.i, Vdb),
- Int1 = Int0#sr{reg=put_reg(R, Int0#sr.reg)},
- Ret = fetch_reg(R, Int1#sr.reg),
- {[{put_list,S1,S2,Ret}], Int1, St};
-put_cg([#k_var{name=R}], #k_binary{segs=Segs}, Le, Vdb, Bef,
- #cg{bfail=Bfail}=St) ->
- %% At run-time, binaries are constructed in three stages:
- %% 1) First the size of the binary is calculated.
- %% 2) Then the binary is allocated.
- %% 3) Then each field in the binary is constructed.
- %% For simplicity, we use the target register to also hold the
- %% size of the binary. Therefore the target register must *not*
- %% be one of the source registers.
-
- %% First allocate the target register.
- Int0 = Bef#sr{reg=put_reg(R, Bef#sr.reg)},
- Target = fetch_reg(R, Int0#sr.reg),
-
- %% Also allocate a scratch register for size calculations.
- Temp = find_scratch_reg(Int0#sr.reg),
-
- %% First generate the code that constructs each field.
- Fail = {f,Bfail},
- PutCode = cg_bin_put(Segs, Fail, Bef),
- {Sis,Int1} = maybe_adjust_stack(Int0, Le#l.i, Le#l.i+1, Vdb, St),
- MaxRegs = max_reg(Bef#sr.reg),
- Aft = clear_dead(Int1, Le#l.i, Vdb),
-
- %% Now generate the complete code for constructing the binary.
- Code = cg_binary(PutCode, Target, Temp, Fail, MaxRegs, Le#l.a),
- {Sis++Code,Aft,St};
-
-%% Map: single variable key.
-put_cg([#k_var{name=R}], #k_map{op=Op,var=Map,
- es=[#k_map_pair{key=#k_var{}=K,val=V}]},
- Le, Vdb, Bef, St0) ->
- {Sis,Int0} = maybe_adjust_stack(Bef, Le#l.i, Le#l.i+1, Vdb, St0),
-
- SrcReg = cg_reg_arg_prefer_y(Map, Int0),
- Line = line(Le#l.a),
-
- List = [cg_reg_arg(K,Int0),cg_reg_arg(V,Int0)],
-
- Live = max_reg(Bef#sr.reg),
-
- %% The target register can reuse one of the source registers.
- Aft0 = clear_dead(Int0, Le#l.i, Vdb),
- Aft = Aft0#sr{reg=put_reg(R, Aft0#sr.reg)},
- Target = fetch_reg(R, Aft#sr.reg),
-
- {Is,St1} = put_cg_map(Line, Op, SrcReg, Target, Live, List, St0),
- {Sis++Is,Aft,St1};
-
-%% Map: (possibly) multiple literal keys.
-put_cg([#k_var{name=R}], #k_map{op=Op,var=Map,es=Es}, Le, Vdb, Bef, St0) ->
-
- %% assert key literals
- [] = [Var || #k_map_pair{key=#k_var{}=Var} <- Es],
-
- {Sis,Int0} = maybe_adjust_stack(Bef, Le#l.i, Le#l.i+1, Vdb, St0),
- SrcReg = cg_reg_arg_prefer_y(Map, Int0),
- Line = line(Le#l.a),
-
- %% fetch registers for values to be put into the map
- List = flatmap(fun(#k_map_pair{key=K,val=V}) ->
- [atomic(K),cg_reg_arg(V, Int0)]
- end, Es),
-
- Live = max_reg(Bef#sr.reg),
-
- %% The target register can reuse one of the source registers.
- Aft0 = clear_dead(Int0, Le#l.i, Vdb),
- Aft = Aft0#sr{reg=put_reg(R, Aft0#sr.reg)},
- Target = fetch_reg(R, Aft#sr.reg),
-
- {Is,St1} = put_cg_map(Line, Op, SrcReg, Target, Live, List, St0),
- {Sis++Is,Aft,St1};
-
-%% Everything else.
-put_cg([#k_var{name=R}], Con, Le, Vdb, Bef, St) ->
- %% Find a place for the return register first.
- Int = Bef#sr{reg=put_reg(R, Bef#sr.reg)},
- Ret = fetch_reg(R, Int#sr.reg),
- Ais = case Con of
- #k_tuple{es=Es} ->
- [{put_tuple,length(Es),Ret}] ++ cg_build_args(Es, Bef);
- Other ->
- [{move,cg_reg_arg(Other, Int),Ret}]
- end,
- {Ais,clear_dead(Int, Le#l.i, Vdb),St}.
-
-
-put_cg_map(Line, Op0, SrcReg, Target, Live, List, St0) ->
- Bfail = St0#cg.bfail,
- Fail = {f,St0#cg.bfail},
- Op = case Op0 of
- assoc -> put_map_assoc;
- exact -> put_map_exact
- end,
- {OkLbl,St1} = new_label(St0),
- {BadLbl,St2} = new_label(St1),
- Is = if
- Bfail =:= 0 orelse Op =:= put_map_assoc ->
- [Line,{Op,{f,0},SrcReg,Target,Live,{list,List}}];
- true ->
- %% Ensure that Target is always set, even if
- %% the map update operation fails. That is necessary
- %% because Target may be included in a test_heap
- %% instruction.
- [Line,
- {Op,{f,BadLbl},SrcReg,Target,Live,{list,List}},
- {jump,{f,OkLbl}},
- {label,BadLbl},
- {move,{atom,ok},Target},
- {jump,Fail},
- {label,OkLbl}]
- end,
- {Is,St2}.
-
-%%%
-%%% Code generation for constructing binaries.
-%%%
-
-cg_binary([{bs_put_binary,Fail,{atom,all},U,_Flags,Src}|PutCode],
- Target, Temp, Fail, MaxRegs, Anno) ->
- Line = line(Anno),
- Live = cg_live(Target, MaxRegs),
- SzCode = cg_bitstr_size(PutCode, Target, Temp, Fail, Live),
- BinFlags = {field_flags,[]},
- Code = [Line|SzCode] ++
- [case member(single_use, Anno) of
- true ->
- {bs_private_append,Fail,Target,U,Src,BinFlags,Target};
- false ->
- {bs_append,Fail,Target,0,MaxRegs,U,Src,BinFlags,Target}
- end] ++ PutCode,
- cg_bin_opt(Code);
-cg_binary(PutCode, Target, Temp, Fail, MaxRegs, Anno) ->
- Line = line(Anno),
- Live = cg_live(Target, MaxRegs),
- {InitOp,SzCode} = cg_binary_size(PutCode, Target, Temp, Fail, Live),
-
- Code = [Line|SzCode] ++ [{InitOp,Fail,Target,0,MaxRegs,
- {field_flags,[]},Target}|PutCode],
- cg_bin_opt(Code).
-
-cg_live({x,X}, MaxRegs) when X =:= MaxRegs -> MaxRegs+1;
-cg_live({x,X}, MaxRegs) when X < MaxRegs -> MaxRegs.
-
-%% Generate code that calculate the size of the bitstr to be
-%% built in BITS.
-
-cg_bitstr_size(PutCode, Target, Temp, Fail, Live) ->
- {Bits,Es} = cg_bitstr_size_1(PutCode, 0, []),
- reverse(cg_gen_binsize(Es, Target, Temp, Fail, Live,
- [{move,{integer,Bits},Target}])).
-
-cg_bitstr_size_1([{bs_put_utf8,_,_,Src}|Next], Bits, Acc) ->
- cg_bitstr_size_1(Next, Bits, [{'*',{bs_utf8_size,Src},8}|Acc]);
-cg_bitstr_size_1([{bs_put_utf16,_,_,Src}|Next], Bits, Acc) ->
- cg_bitstr_size_1(Next, Bits, [{'*',{bs_utf16_size,Src},8}|Acc]);
-cg_bitstr_size_1([{bs_put_utf32,_,_,_}|Next], Bits, Acc) ->
- cg_bitstr_size_1(Next, Bits+32, Acc);
-cg_bitstr_size_1([{_,_,S,U,_,Src}|Next], Bits, Acc) ->
- case S of
- {integer,N} -> cg_bitstr_size_1(Next, Bits+N*U, Acc);
- {atom,all} -> cg_bitstr_size_1(Next, Bits, [{bit_size,Src}|Acc]);
- _ when U =:= 1 -> cg_bitstr_size_1(Next, Bits, [S|Acc]);
- _ -> cg_bitstr_size_1(Next, Bits, [{'*',S,U}|Acc])
- end;
-cg_bitstr_size_1([], Bits, Acc) -> {Bits,Acc}.
-
-%% Generate code that calculate the size of the bitstr to be
-%% built in BYTES or BITS (depending on what is easiest).
-
-cg_binary_size(PutCode, Target, Temp, Fail, Live) ->
- {InitInstruction,Szs} = cg_binary_size_1(PutCode, 0, []),
- SizeExpr = reverse(cg_gen_binsize(Szs, Target, Temp, Fail, Live, [{move,{integer,0},Target}])),
- {InitInstruction,SizeExpr}.
-
-cg_binary_size_1([{bs_put_utf8,_Fail,_Flags,Src}|T], Bits, Acc) ->
- cg_binary_size_1(T, Bits, [{8,{bs_utf8_size,Src}}|Acc]);
-cg_binary_size_1([{bs_put_utf16,_Fail,_Flags,Src}|T], Bits, Acc) ->
- cg_binary_size_1(T, Bits, [{8,{bs_utf16_size,Src}}|Acc]);
-cg_binary_size_1([{bs_put_utf32,_Fail,_Flags,_Src}|T], Bits, Acc) ->
- cg_binary_size_1(T, Bits+32, Acc);
-cg_binary_size_1([{_Put,_Fail,S,U,_Flags,Src}|T], Bits, Acc) ->
- cg_binary_size_2(S, U, Src, T, Bits, Acc);
-cg_binary_size_1([], Bits, Acc) ->
- Bytes = Bits div 8,
- RemBits = Bits rem 8,
- Sizes0 = sort([{1,{integer,RemBits}},{8,{integer,Bytes}}|Acc]),
- Sizes = filter(fun({_,{integer,0}}) -> false;
- (_) -> true end, Sizes0),
- case Sizes of
- [{1,_}|_] ->
- {bs_init_bits,cg_binary_bytes_to_bits(Sizes, [])};
- [{8,_}|_] ->
- {bs_init2,[E || {8,E} <- Sizes]};
- [] ->
- {bs_init_bits,[]}
- end.
-
-cg_binary_size_2({integer,N}, U, _, Next, Bits, Acc) ->
- cg_binary_size_1(Next, Bits+N*U, Acc);
-cg_binary_size_2({atom,all}, U, E, Next, Bits, Acc) ->
- if
- U rem 8 =:= 0 ->
- cg_binary_size_1(Next, Bits, [{8,{byte_size,E}}|Acc]);
- true ->
- cg_binary_size_1(Next, Bits, [{1,{bit_size,E}}|Acc])
- end;
-cg_binary_size_2(Reg, 1, _, Next, Bits, Acc) ->
- cg_binary_size_1(Next, Bits, [{1,Reg}|Acc]);
-cg_binary_size_2(Reg, 8, _, Next, Bits, Acc) ->
- cg_binary_size_1(Next, Bits, [{8,Reg}|Acc]);
-cg_binary_size_2(Reg, U, _, Next, Bits, Acc) ->
- cg_binary_size_1(Next, Bits, [{1,{'*',Reg,U}}|Acc]).
-
-cg_binary_bytes_to_bits([{8,{integer,N}}|T], Acc) ->
- cg_binary_bytes_to_bits(T, [{integer,8*N}|Acc]);
-cg_binary_bytes_to_bits([{8,{byte_size,Reg}}|T], Acc) ->
- cg_binary_bytes_to_bits(T, [{bit_size,Reg}|Acc]);
-cg_binary_bytes_to_bits([{8,Reg}|T], Acc) ->
- cg_binary_bytes_to_bits(T, [{'*',Reg,8}|Acc]);
-cg_binary_bytes_to_bits([{1,Sz}|T], Acc) ->
- cg_binary_bytes_to_bits(T, [Sz|Acc]);
-cg_binary_bytes_to_bits([], Acc) ->
- cg_binary_bytes_to_bits_1(sort(Acc)).
-
-cg_binary_bytes_to_bits_1([{integer,I},{integer,J}|T]) ->
- cg_binary_bytes_to_bits_1([{integer,I+J}|T]);
-cg_binary_bytes_to_bits_1([H|T]) ->
- [H|cg_binary_bytes_to_bits_1(T)];
-cg_binary_bytes_to_bits_1([]) -> [].
-
-cg_gen_binsize([{'*',{bs_utf8_size,Src},B}|T], Target, Temp, Fail, Live, Acc) ->
- Size = {bs_utf8_size,Fail,Src,Temp},
- Add = {bs_add,Fail,[Target,Temp,B],Target},
- cg_gen_binsize(T, Target, Temp, Fail, Live,
- [Add,Size|Acc]);
-cg_gen_binsize([{'*',{bs_utf16_size,Src},B}|T], Target, Temp, Fail, Live, Acc) ->
- Size = {bs_utf16_size,Fail,Src,Temp},
- Add = {bs_add,Fail,[Target,Temp,B],Target},
- cg_gen_binsize(T, Target, Temp, Fail, Live,
- [Add,Size|Acc]);
-cg_gen_binsize([{'*',A,B}|T], Target, Temp, Fail, Live, Acc) ->
- cg_gen_binsize(T, Target, Temp, Fail, Live,
- [{bs_add,Fail,[Target,A,B],Target}|Acc]);
-cg_gen_binsize([{bit_size,B}|T], Target, Temp, Fail, Live, Acc) ->
- cg_gen_binsize([Temp|T], Target, Temp, Fail, Live,
- [{gc_bif,bit_size,Fail,Live,[B],Temp}|Acc]);
-cg_gen_binsize([{byte_size,B}|T], Target, Temp, Fail, Live, Acc) ->
- cg_gen_binsize([Temp|T], Target, Temp, Fail, Live,
- [{gc_bif,byte_size,Fail,Live,[B],Temp}|Acc]);
-cg_gen_binsize([{bs_utf8_size,B}|T], Target, Temp, Fail, Live, Acc) ->
- cg_gen_binsize([Temp|T], Target, Temp, Fail, Live,
- [{bs_utf8_size,Fail,B,Temp}|Acc]);
-cg_gen_binsize([{bs_utf16_size,B}|T], Target, Temp, Fail, Live, Acc) ->
- cg_gen_binsize([Temp|T], Target, Temp, Fail, Live,
- [{bs_utf16_size,Fail,B,Temp}|Acc]);
-cg_gen_binsize([E0|T], Target, Temp, Fail, Live, Acc) ->
- cg_gen_binsize(T, Target, Temp, Fail, Live,
- [{bs_add,Fail,[Target,E0,1],Target}|Acc]);
-cg_gen_binsize([], _, _, _, _, Acc) -> Acc.
-
-
-%% cg_bin_opt(Code0) -> Code
-%% Optimize the size calculations for binary construction.
-
-cg_bin_opt([{move,S1,{x,X}=D},{gc_bif,Op,Fail,Live0,As,Dst}|Is]) ->
- Live = if
- X + 1 =:= Live0 -> X;
- true -> Live0
- end,
- [{gc_bif,Op,Fail,Live,As,D}|cg_bin_opt([{move,S1,Dst}|Is])];
-cg_bin_opt([{move,_,_}=I1,{Op,_,_,_}=I2|Is])
- when Op =:= bs_utf8_size orelse Op =:= bs_utf16_size ->
- [I2|cg_bin_opt([I1|Is])];
-cg_bin_opt([{bs_add,_,[{integer,0},Src,1],Dst}|Is]) ->
- cg_bin_opt_1([{move,Src,Dst}|Is]);
-cg_bin_opt([{bs_add,_,[Src,{integer,0},_],Dst}|Is]) ->
- cg_bin_opt_1([{move,Src,Dst}|Is]);
-cg_bin_opt(Is) ->
- cg_bin_opt_1(Is).
-
-cg_bin_opt_1([{move,Size,D},{bs_append,Fail,D,Extra,Regs,U,Bin,Flags,D}|Is]) ->
- [{bs_append,Fail,Size,Extra,Regs,U,Bin,Flags,D}|cg_bin_opt(Is)];
-cg_bin_opt_1([{move,Size,D},{bs_private_append,Fail,D,U,Bin,Flags,D}|Is]) ->
- [{bs_private_append,Fail,Size,U,Bin,Flags,D}|cg_bin_opt(Is)];
-cg_bin_opt_1([{move,Size,D},{Op,Fail,D,Extra,Regs,Flags,D}|Is])
- when Op =:= bs_init2; Op =:= bs_init_bits ->
- Bytes = case Size of
- {integer,Int} -> Int;
- _ -> Size
- end,
- [{Op,Fail,Bytes,Extra,Regs,Flags,D}|cg_bin_opt(Is)];
-cg_bin_opt_1([{move,S1,D},{bs_add,Fail,[D,S2,U],Dst}|Is]) ->
- cg_bin_opt([{bs_add,Fail,[S1,S2,U],Dst}|Is]);
-cg_bin_opt_1([{move,S1,D},{bs_add,Fail,[S2,D,U],Dst}|Is]) ->
- cg_bin_opt([{bs_add,Fail,[S2,S1,U],Dst}|Is]);
-cg_bin_opt_1([I|Is]) ->
- [I|cg_bin_opt(Is)];
-cg_bin_opt_1([]) ->
- [].
-
-cg_bin_put(#k_bin_seg{size=S0,unit=U,type=T,flags=Fs,seg=E0,next=Next},
- Fail, Bef) ->
- S1 = cg_reg_arg(S0, Bef),
- E1 = cg_reg_arg(E0, Bef),
- {Format,Op} = case T of
- integer -> {plain,bs_put_integer};
- utf8 -> {utf,bs_put_utf8};
- utf16 -> {utf,bs_put_utf16};
- utf32 -> {utf,bs_put_utf32};
- binary -> {plain,bs_put_binary};
- float -> {plain,bs_put_float}
- end,
- case Format of
- plain ->
- [{Op,Fail,S1,U,{field_flags,Fs},E1}|cg_bin_put(Next, Fail, Bef)];
- utf ->
- [{Op,Fail,{field_flags,Fs},E1}|cg_bin_put(Next, Fail, Bef)]
- end;
-cg_bin_put(#k_bin_end{}, _, _) -> [].
-
-cg_build_args(As, Bef) ->
- [{put,cg_reg_arg(A, Bef)} || A <- As].
-
-%% return_cg([Val], Le, Vdb, Bef, St) -> {[Ainstr],Aft,St}.
-%% break_cg([Val], Le, Vdb, Bef, St) -> {[Ainstr],Aft,St}.
-%% These are very simple, just put return/break values in registers
-%% from 0, then return/break. Use the call setup to clean up stack,
-%% but must clear registers to ensure sr_merge works correctly.
-
-return_cg(Rs, Le, Vdb, Bef, St) ->
- {Ms,Int} = cg_setup_call(Rs, Bef, Le#l.i, Vdb),
- {Ms ++ [return],Int#sr{reg=clear_regs(Int#sr.reg)},St}.
-
-break_cg(Bs, Le, Vdb, Bef, St) ->
- {Ms,Int} = cg_setup_call(Bs, Bef, Le#l.i, Vdb),
- {Ms ++ [{jump,{f,St#cg.break}}],
- Int#sr{reg=clear_regs(Int#sr.reg)},St}.
-
-guard_break_cg(Bs, #l{i=I}, Vdb, #sr{reg=Reg0}=Bef, St) ->
- #sr{reg=Reg1} = Int = clear_dead(Bef, I, Vdb),
- Reg2 = trim_free(Reg1),
- NumLocked = length(Reg2),
- Moves0 = gen_moves(Bs, Bef, NumLocked, []),
- Moves = order_moves(Moves0, find_scratch_reg(Reg0)),
- {BreakVars,_} = mapfoldl(fun(_, RegNum) ->
- {{RegNum,gbreakvar},RegNum+1}
- end, length(Reg2), Bs),
- Reg = Reg2 ++ BreakVars,
- Aft = Int#sr{reg=Reg},
- {Moves ++ [{jump,{f,St#cg.break}}],Aft,St}.
-
-%% cg_reg_arg(Arg0, Info) -> Arg
-%% cg_reg_args([Arg0], Info) -> [Arg]
-%% Convert argument[s] into registers. Literal values are returned unchanged.
-
-cg_reg_args(As, Bef) -> [cg_reg_arg(A, Bef) || A <- As].
-
-cg_reg_arg(#k_var{name=V}, Bef) -> fetch_var(V, Bef);
-cg_reg_arg(Literal, _) -> atomic(Literal).
-
-cg_reg_arg_prefer_y(#k_var{name=V}, Bef) -> fetch_var_prefer_y(V, Bef);
-cg_reg_arg_prefer_y(Literal, _) -> atomic(Literal).
-
-%% cg_setup_call([Arg], Bef, Cur, Vdb) -> {[Instr],Aft}.
-%% Do the complete setup for a call/enter.
-
-cg_setup_call(As, Bef, I, Vdb) ->
- {Ms,Int0} = cg_call_args(As, Bef, I, Vdb),
- %% Have set up arguments, can now clean up, compress and save to stack.
- Int1 = Int0#sr{stk=clear_dead_stk(Int0#sr.stk, I, Vdb),res=[]},
- {Sis,Int2} = adjust_stack(Int1, I, I+1, Vdb),
- {Ms ++ Sis,Int2}.
-
-%% cg_call_args([Arg], SrState) -> {[Instr],SrState}.
-%% Setup the arguments to a call/enter/bif. Put the arguments into
-%% consecutive registers starting at {x,0} moving any data which
-%% needs to be saved. Return a modified SrState structure with the
-%% new register contents. N.B. the resultant register info will
-%% contain non-variable values when there are non-variable values.
-%%
-%% This routine is complicated by unsaved values in x registers.
-%% We'll move away any unsaved values that are in the registers
-%% to be overwritten by the arguments.
-
-cg_call_args(As, Bef, I, Vdb) ->
- Regs0 = load_arg_regs(Bef#sr.reg, As),
- Unsaved = unsaved_registers(Regs0, Bef#sr.stk, I, I+1, Vdb),
- {UnsavedMoves,Regs} = move_unsaved(Unsaved, Bef#sr.reg, Regs0),
- Moves0 = gen_moves(As, Bef),
- Moves = order_moves(Moves0, find_scratch_reg(Regs)),
- {UnsavedMoves ++ Moves,Bef#sr{reg=Regs}}.
-
-%% load_arg_regs([Reg], Arguments) -> [Reg]
-%% Update the register descriptor to include the arguments (from {x,0}
-%% and upwards). Values in argument register are overwritten.
-%% Values in x registers above the arguments are preserved.
-
-load_arg_regs(Regs, As) -> load_arg_regs(Regs, As, 0).
-
-load_arg_regs([_|Rs], [#k_var{name=V}|As], I) -> [{I,V}|load_arg_regs(Rs, As, I+1)];
-load_arg_regs([_|Rs], [A|As], I) -> [{I,A}|load_arg_regs(Rs, As, I+1)];
-load_arg_regs([], [#k_var{name=V}|As], I) -> [{I,V}|load_arg_regs([], As, I+1)];
-load_arg_regs([], [A|As], I) -> [{I,A}|load_arg_regs([], As, I+1)];
-load_arg_regs(Rs, [], _) -> Rs.
-
-%% Returns the variables must be saved and are currently in the
-%% x registers that are about to be overwritten by the arguments.
-
-unsaved_registers(Regs, Stk, Fb, Lf, Vdb) ->
- [V || {V,F,L} <- Vdb,
- F < Fb,
- L >= Lf,
- not on_stack(V, Stk),
- not in_reg(V, Regs)].
-
-in_reg(V, Regs) -> keymember(V, 2, Regs).
-
-%% Move away unsaved variables from the registers that are to be
-%% overwritten by the arguments.
-move_unsaved(Vs, OrigRegs, NewRegs) ->
- move_unsaved(Vs, OrigRegs, NewRegs, []).
-
-move_unsaved([V|Vs], OrigRegs, NewRegs0, Acc) ->
- NewRegs = put_reg(V, NewRegs0),
- Src = fetch_reg(V, OrigRegs),
- Dst = fetch_reg(V, NewRegs),
- move_unsaved(Vs, OrigRegs, NewRegs, [{move,Src,Dst}|Acc]);
-move_unsaved([], _, Regs, Acc) -> {Acc,Regs}.
-
-%% gen_moves(As, Sr)
-%% Generate the basic move instruction to move the arguments
-%% to their proper registers. The list will be sorted on
-%% destinations. (I.e. the move to {x,0} will be first --
-%% see the comment to order_moves/2.)
-
-gen_moves(As, Sr) -> gen_moves(As, Sr, 0, []).
-
-gen_moves([#k_var{name=V}|As], Sr, I, Acc) ->
- case fetch_var(V, Sr) of
- {x,I} -> gen_moves(As, Sr, I+1, Acc);
- Reg -> gen_moves(As, Sr, I+1, [{move,Reg,{x,I}}|Acc])
- end;
-gen_moves([A0|As], Sr, I, Acc) ->
- A = atomic(A0),
- gen_moves(As, Sr, I+1, [{move,A,{x,I}}|Acc]);
-gen_moves([], _, _, Acc) -> lists:keysort(3, Acc).
-
-%% order_moves([Move], ScratchReg) -> [Move]
-%% Orders move instruction so that source registers are not
-%% destroyed before they are used. If there are cycles
-%% (such as {move,{x,0},{x,1}}, {move,{x,1},{x,1}}),
-%% the scratch register is used to break up the cycle.
-%% If possible, the first move of the input list is placed
-%% last in the result list (to make the move to {x,0} occur
-%% just before the call to allow the Beam loader to coalesce
-%% the instructions).
-
-order_moves(Ms, Scr) -> order_moves(Ms, Scr, []).
-
-order_moves([{move,_,_}=M|Ms0], ScrReg, Acc0) ->
- {Chain,Ms} = collect_chain(Ms0, [M], ScrReg),
- Acc = reverse(Chain, Acc0),
- order_moves(Ms, ScrReg, Acc);
-order_moves([], _, Acc) -> Acc.
-
-collect_chain(Ms, Path, ScrReg) ->
- collect_chain(Ms, Path, [], ScrReg).
-
-collect_chain([{move,Src,Same}=M|Ms0], [{move,Same,_}|_]=Path, Others, ScrReg) ->
- case lists:keyfind(Src, 3, Path) of
- false ->
- collect_chain(reverse(Others, Ms0), [M|Path], [], ScrReg);
- _ -> % We have a cycle.
- {break_up_cycle(M, Path, ScrReg),reverse(Others, Ms0)}
- end;
-collect_chain([M|Ms], Path, Others, ScrReg) ->
- collect_chain(Ms, Path, [M|Others], ScrReg);
-collect_chain([], Path, Others, _) ->
- {Path,Others}.
-
-break_up_cycle({move,Src,_}=M, Path, ScrReg) ->
- [{move,ScrReg,Src},M|break_up_cycle1(Src, Path, ScrReg)].
-
-break_up_cycle1(Dst, [{move,Src,Dst}|Path], ScrReg) ->
- [{move,Src,ScrReg}|Path];
-break_up_cycle1(Dst, [M|Path], LastMove) ->
- [M|break_up_cycle1(Dst, Path, LastMove)].
-
-%% clear_dead(Sr, Until, Vdb) -> Aft.
-%% Remove all variables in Sr which have died AT ALL so far.
-
-clear_dead(#sr{stk=Stk}=Sr0, Until, Vdb) ->
- Sr = Sr0#sr{reg=clear_dead_reg(Sr0, Until, Vdb),
- stk=clear_dead_stk(Stk, Until, Vdb)},
- reserve(Sr).
-
-clear_dead_reg(Sr, Until, Vdb) ->
- [case R of
- {_I,V} = IV ->
- case vdb_find(V, Vdb) of
- {V,_,L} when L > Until -> IV;
- _ -> free %Remove anything else
- end;
- {reserved,_I,_V}=Reserved -> Reserved;
- free -> free
- end || R <- Sr#sr.reg].
-
-clear_dead_stk(Stk, Until, Vdb) ->
- [case S of
- {V} = T ->
- case vdb_find(V, Vdb) of
- {V,_,L} when L > Until -> T;
- _ -> dead %Remove anything else
- end;
- free -> free;
- dead -> dead
- end || S <- Stk].
-
-
-%% sr_merge(Sr1, Sr2) -> Sr.
-%% Merge two stack/register states keeping the longest of both stack
-%% and register. Perform consistency check on both, elements must be
-%% the same. Allow frame size 'void' to make easy creation of
-%% "empty" frame.
-
-sr_merge(#sr{reg=R1,stk=S1,res=[]}, #sr{reg=R2,stk=S2,res=[]}) ->
- #sr{reg=longest(R1, R2),stk=longest(S1, S2),res=[]};
-sr_merge(void, S2) -> S2#sr{res=[]}.
-
-longest([H|T1], [H|T2]) -> [H|longest(T1, T2)];
-longest([dead|T1], [free|T2]) -> [dead|longest(T1, T2)];
-longest([free|T1], [dead|T2]) -> [dead|longest(T1, T2)];
-longest([dead|_] = L, []) -> L;
-longest([], [dead|_] = L) -> L;
-longest([free|_] = L, []) -> L;
-longest([], [free|_] = L) -> L;
-longest([], []) -> [].
-
-trim_free([R|Rs0]) ->
- case {trim_free(Rs0),R} of
- {[],free} -> [];
- {Rs,R} -> [R|Rs]
- end;
-trim_free([]) -> [].
-
-%% maybe_adjust_stack(Bef, FirstBefore, LastFrom, Vdb, St) -> {[Ainstr],Aft}.
-%% Adjust the stack, but only if the code is inside a catch and not
-%% inside a guard. Use this funtion before instructions that may
-%% cause an exception.
-
-maybe_adjust_stack(Bef, Fb, Lf, Vdb, St) ->
- case St of
- #cg{in_catch=true,bfail=0} ->
- adjust_stack(Bef, Fb, Lf, Vdb);
- #cg{} ->
- {[],Bef}
- end.
-
-%% adjust_stack(Bef, FirstBefore, LastFrom, Vdb) -> {[Ainstr],Aft}.
-%% Do complete stack adjustment by compressing stack and adding
-%% variables to be saved. Try to optimise ordering on stack by
-%% having reverse order to their lifetimes.
-%%
-%% In Beam, there is a fixed stack frame and no need to do stack compression.
-
-adjust_stack(Bef, Fb, Lf, Vdb) ->
- Stk0 = Bef#sr.stk,
- {Stk1,Saves} = save_stack(Stk0, Fb, Lf, Vdb),
- {saves(Saves, Bef#sr.reg, Stk1),
- Bef#sr{stk=Stk1}}.
-
-%% save_stack(Stack, FirstBefore, LastFrom, Vdb) -> {[SaveVar],NewStack}.
-%% Save variables which are used past current point and which are not
-%% already on the stack.
-
-save_stack(Stk0, Fb, Lf, Vdb) ->
- %% New variables that are in use but not on stack.
- New = new_not_on_stack(Stk0, Fb, Lf, Vdb),
-
- %% Add new variables that are not just dropped immediately.
- %% N.B. foldr works backwards from the end!!
- Saves = [V || {V,_,_} <- keysort(3, New)],
- Stk1 = foldr(fun (V, Stk) -> put_stack(V, Stk) end, Stk0, Saves),
- {Stk1,Saves}.
-
-%% new_not_on_stack(Stack, FirstBefore, LastFrom, Vdb) ->
-%% [{Variable,First,Last}]
-%% Return information about all variables that are used past current
-%% point and that are not already on the stack.
-
-new_not_on_stack(Stk, Fb, Lf, Vdb) ->
- [VFL || {V,F,L} = VFL <- Vdb,
- F < Fb,
- L >= Lf,
- not on_stack(V, Stk)].
-
-%% saves([SaveVar], Reg, Stk) -> [{move,Reg,Stk}].
-%% Generate move instructions to save variables onto stack. The
-%% stack/reg info used is that after the new stack has been made.
-
-saves(Ss, Reg, Stk) ->
- [{move,fetch_reg(V, Reg),fetch_stack(V, Stk)} || V <- Ss].
-
-%% fetch_var(VarName, StkReg) -> r{R} | sp{Sp}.
-%% find_var(VarName, StkReg) -> ok{r{R} | sp{Sp}} | error.
-%% Fetch/find a variable in either the registers or on the
-%% stack. Fetch KNOWS it's there.
-
-fetch_var(V, Sr) ->
- case find_reg(V, Sr#sr.reg) of
- {ok,R} -> R;
- error -> fetch_stack(V, Sr#sr.stk)
- end.
-
-fetch_var_prefer_y(V, #sr{reg=Reg,stk=Stk}) ->
- case find_stack(V, Stk) of
- {ok,R} -> R;
- error -> fetch_reg(V, Reg)
- end.
-
-load_vars(Vs, Regs) ->
- foldl(fun (#k_var{name=V}, Rs) -> put_reg(V, Rs) end, Regs, Vs).
-
-%% put_reg(Val, Regs) -> Regs.
-%% find_reg(Val, Regs) -> {ok,r{R}} | error.
-%% fetch_reg(Val, Regs) -> r{R}.
-%% Functions to interface the registers.
-
-% put_regs(Vs, Rs) -> foldl(fun put_reg/2, Rs, Vs).
-
-put_reg(V, Rs) -> put_reg_1(V, Rs, 0).
-
-put_reg_1(V, [free|Rs], I) -> [{I,V}|Rs];
-put_reg_1(V, [{reserved,I,V}|Rs], I) -> [{I,V}|Rs];
-put_reg_1(V, [R|Rs], I) -> [R|put_reg_1(V, Rs, I+1)];
-put_reg_1(V, [], I) -> [{I,V}].
-
-fetch_reg(V, [{I,V}|_]) -> {x,I};
-fetch_reg(V, [_|SRs]) -> fetch_reg(V, SRs).
-
-find_reg(V, [{I,V}|_]) -> {ok,{x,I}};
-find_reg(V, [_|SRs]) -> find_reg(V, SRs);
-find_reg(_, []) -> error.
-
-%% For the bit syntax, we need a scratch register if we are constructing
-%% a binary that will not be used.
-
-find_scratch_reg(Rs) -> find_scratch_reg(Rs, 0).
-
-find_scratch_reg([free|_], I) -> {x,I};
-find_scratch_reg([_|Rs], I) -> find_scratch_reg(Rs, I+1);
-find_scratch_reg([], I) -> {x,I}.
-
-replace_reg_contents(Old, New, [{I,Old}|Rs]) -> [{I,New}|Rs];
-replace_reg_contents(Old, New, [R|Rs]) -> [R|replace_reg_contents(Old, New, Rs)].
-
-%%clear_regs(Regs) -> map(fun (R) -> free end, Regs).
-clear_regs(_) -> [].
-
-max_reg(Regs) ->
- foldl(fun ({I,_}, _) -> I;
- (_, Max) -> Max end,
- -1, Regs) + 1.
-
-%% put_stack(Val, [{Val}]) -> [{Val}].
-%% fetch_stack(Var, Stk) -> sp{S}.
-%% find_stack(Var, Stk) -> ok{sp{S}} | error.
-%% Functions to interface the stack.
-
-put_stack(Val, []) -> [{Val}];
-put_stack(Val, [dead|Stk]) -> [{Val}|Stk];
-put_stack(Val, [free|Stk]) -> [{Val}|Stk];
-put_stack(Val, [NotFree|Stk]) -> [NotFree|put_stack(Val, Stk)].
-
-put_stack_carefully(Val, Stk0) ->
- try
- put_stack_carefully1(Val, Stk0)
- catch
- throw:error ->
- error
- end.
-
-put_stack_carefully1(_, []) -> throw(error);
-put_stack_carefully1(Val, [dead|Stk]) -> [{Val}|Stk];
-put_stack_carefully1(Val, [free|Stk]) -> [{Val}|Stk];
-put_stack_carefully1(Val, [NotFree|Stk]) ->
- [NotFree|put_stack_carefully1(Val, Stk)].
-
-fetch_stack(Var, Stk) -> fetch_stack(Var, Stk, 0).
-
-fetch_stack(V, [{V}|_], I) -> {yy,I};
-fetch_stack(V, [_|Stk], I) -> fetch_stack(V, Stk, I+1).
-
-find_stack(Var, Stk) -> find_stack(Var, Stk, 0).
-
-find_stack(V, [{V}|_], I) -> {ok,{yy,I}};
-find_stack(V, [_|Stk], I) -> find_stack(V, Stk, I+1);
-find_stack(_, [], _) -> error.
-
-on_stack(V, Stk) -> keymember(V, 1, Stk).
-
-%% put_catch(CatchTag, Stack) -> Stack'
-%% drop_catch(CatchTag, Stack) -> Stack'
-%% Special interface for putting and removing catch tags, to ensure that
-%% catches nest properly. Also used for try tags.
-
-put_catch(Tag, Stk0) -> put_catch(Tag, reverse(Stk0), []).
-
-put_catch(Tag, [], Stk) ->
- put_stack({catch_tag,Tag}, Stk);
-put_catch(Tag, [{{catch_tag,_}}|_]=RevStk, Stk) ->
- reverse(RevStk, put_stack({catch_tag,Tag}, Stk));
-put_catch(Tag, [Other|Stk], Acc) ->
- put_catch(Tag, Stk, [Other|Acc]).
-
-drop_catch(Tag, [{{catch_tag,Tag}}|Stk]) -> [free|Stk];
-drop_catch(Tag, [Other|Stk]) -> [Other|drop_catch(Tag, Stk)].
-
-%% atomic(Klit) -> Lit.
-%% atomic_list([Klit]) -> [Lit].
-
-atomic(#k_literal{val=V}) -> {literal,V};
-atomic(#k_int{val=I}) -> {integer,I};
-atomic(#k_float{val=F}) -> {float,F};
-atomic(#k_atom{val=A}) -> {atom,A};
-%%atomic(#k_char{val=C}) -> {char,C};
-atomic(#k_nil{}) -> nil.
-
-%% new_label(St) -> {L,St}.
-
-new_label(#cg{lcount=Next}=St) ->
- {Next,St#cg{lcount=Next+1}}.
-
-%% line(Le) -> {line,[] | {location,File,Line}}
-%% Create a line instruction, containing information about
-%% the current filename and line number. A line information
-%% instruction should be placed before any operation that could
-%% cause an exception.
-
-line(#l{a=Anno}) ->
- line(Anno);
-line([Line,{file,Name}]) when is_integer(Line) ->
- line_1(Name, Line);
-line([_|_]=A) ->
- {Name,Line} = find_loc(A, no_file, 0),
- line_1(Name, Line);
-line([]) ->
- {line,[]}.
-
-line_1(no_file, _) ->
- {line,[]};
-line_1(_, 0) ->
- %% Missing line number or line number 0.
- {line,[]};
-line_1(Name, Line) ->
- {line,[{location,Name,Line}]}.
-
-find_loc([Line|T], File, _) when is_integer(Line) ->
- find_loc(T, File, Line);
-find_loc([{file,File}|T], _, Line) ->
- find_loc(T, File, Line);
-find_loc([_|T], File, Line) ->
- find_loc(T, File, Line);
-find_loc([], File, Line) -> {File,Line}.
-
-flatmapfoldl(F, Accu0, [Hd|Tail]) ->
- {R,Accu1} = F(Hd, Accu0),
- {Rs,Accu2} = flatmapfoldl(F, Accu1, Tail),
- {R++Rs,Accu2};
-flatmapfoldl(_, Accu, []) -> {[],Accu}.
-
-%% Keep track of life time for variables.
-%%
-%% init_vars([{var,VarName}]) -> Vdb.
-%% new_vars([VarName], I, Vdb) -> Vdb.
-%% use_vars([VarName], I, Vdb) -> Vdb.
-%% add_var(VarName, F, L, Vdb) -> Vdb.
-%%
-%% The list of variable names for new_vars/3 and use_vars/3
-%% must be sorted.
-
-init_vars(Vs) ->
- vdb_new(Vs).
-
-new_vars([], _, Vdb) -> Vdb;
-new_vars([V], I, Vdb) -> vdb_store_new(V, {V,I,I}, Vdb);
-new_vars(Vs, I, Vdb) -> vdb_update_vars(Vs, Vdb, I).
-
-use_vars([], _, Vdb) ->
- Vdb;
-use_vars([V], I, Vdb) ->
- case vdb_find(V, Vdb) of
- {V,F,L} when I > L -> vdb_update(V, {V,F,I}, Vdb);
- {V,_,_} -> Vdb;
- error -> vdb_store_new(V, {V,I,I}, Vdb)
- end;
-use_vars(Vs, I, Vdb) -> vdb_update_vars(Vs, Vdb, I).
-
-add_var(V, F, L, Vdb) ->
- vdb_store_new(V, {V,F,L}, Vdb).
-
-%% vdb
-
-vdb_new(Vs) ->
- ordsets:from_list([{V,0,0} || #k_var{name=V} <- Vs]).
-
--type var() :: atom().
-
--spec vdb_find(var(), [vdb_entry()]) -> 'error' | vdb_entry().
-
-vdb_find(V, Vdb) ->
- case lists:keyfind(V, 1, Vdb) of
- false -> error;
- Vd -> Vd
- end.
-
-vdb_update(V, Update, [{V,_,_}|Vdb]) ->
- [Update|Vdb];
-vdb_update(V, Update, [Vd|Vdb]) ->
- [Vd|vdb_update(V, Update, Vdb)].
-
-vdb_store_new(V, New, [{V1,_,_}=Vd|Vdb]) when V > V1 ->
- [Vd|vdb_store_new(V, New, Vdb)];
-vdb_store_new(V, New, [{V1,_,_}|_]=Vdb) when V < V1 ->
- [New|Vdb];
-vdb_store_new(_, New, []) -> [New].
-
-vdb_update_vars([V|_]=Vs, [{V1,_,_}=Vd|Vdb], I) when V > V1 ->
- [Vd|vdb_update_vars(Vs, Vdb, I)];
-vdb_update_vars([V|Vs], [{V1,_,_}|_]=Vdb, I) when V < V1 ->
- %% New variable.
- [{V,I,I}|vdb_update_vars(Vs, Vdb, I)];
-vdb_update_vars([V|Vs], [{_,F,L}=Vd|Vdb], I) ->
- %% Existing variable.
- if
- I > L -> [{V,F,I}|vdb_update_vars(Vs, Vdb, I)];
- true -> [Vd|vdb_update_vars(Vs, Vdb, I)]
- end;
-vdb_update_vars([V|Vs], [], I) ->
- %% New variable.
- [{V,I,I}|vdb_update_vars(Vs, [], I)];
-vdb_update_vars([], Vdb, _) -> Vdb.
-
-%% vdb_sub(Min, Max, Vdb) -> Vdb.
-%% Extract variables which are used before and after Min. Lock
-%% variables alive after Max.
-
-vdb_sub(Min, Max, Vdb) ->
- [ if L >= Max -> {V,F,locked};
- true -> Vd
- end || {V,F,L}=Vd <- Vdb,
- F < Min,
- L >= Min ].