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+%% ``The contents of this file are subject to the Erlang Public License,
+%% Version 1.1, (the "License"); you may not use this file except in
+%% compliance with the License. You should have received a copy of the
+%% Erlang Public License along with this software. If not, it can be
+%% retrieved via the world wide web at http://www.erlang.org/.
+%%
+%% Software distributed under the License is distributed on an "AS IS"
+%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%% the License for the specific language governing rights and limitations
+%% under the License.
+%%
+%% The Initial Developer of the Original Code is Ericsson Utvecklings AB.
+%% Portions created by Ericsson are Copyright 1999, Ericsson Utvecklings
+%% AB. All Rights Reserved.''
+%%
+%% $Id: v3_codegen.erl,v 1.1 2008/12/17 09:53:42 mikpe Exp $
+%%
+%% Purpose : Code generator for Beam.
+
+%% 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 v3_life module 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.
+
+-module(v3_codegen).
+
+%% The main interface.
+-export([module/2]).
+
+-import(lists, [member/2,keymember/3,keysort/2,keysearch/3,append/1,
+ map/2,flatmap/2,foldl/3,foldr/3,mapfoldl/3,
+ sort/1,reverse/1,reverse/2]).
+-import(v3_life, [vdb_find/2]).
+
+%%-compile([export_all]).
+
+-include("v3_life.hrl").
+
+%% Main codegen structure.
+-record(cg, {lcount=1, %Label counter
+ mod, %Current module
+ func, %Current function
+ finfo, %Function info label
+ fcode, %Function code label
+ btype, %Type of bif used.
+ bfail, %Fail label of bif
+ break, %Break label
+ recv, %Receive label
+ is_top_block, %Boolean: top block or not
+ functable = [], %Table of local functions:
+ %[{{Name, Arity}, Label}...]
+ in_catch=false, %Inside a catch or not.
+ need_frame, %Need a stack frame.
+ new_funs=true}). %Generate new fun instructions.
+
+%% Stack/register state record.
+-record(sr, {reg=[], %Register table
+ stk=[], %Stack table
+ res=[]}). %Reserved regs: [{reserved,I,V}]
+
+module({Mod,Exp,Attr,Forms}, Options) ->
+ NewFunsFlag = not member(no_new_funs, Options),
+ {Fs,St} = functions(Forms, #cg{mod=Mod,new_funs=NewFunsFlag}),
+ {ok,{Mod,Exp,Attr,Fs,St#cg.lcount}}.
+
+functions(Forms, St0) ->
+ mapfoldl(fun (F, St) -> function(F, St) end, St0#cg{lcount=1}, Forms).
+
+function({function,Name,Arity,As0,Vb,Vdb}, St0) ->
+ %%ok = io:fwrite("cg ~w:~p~n", [?LINE,{Name,Arity}]),
+ St1 = St0#cg{func={Name,Arity}},
+ {Fun,St2} = cg_fun(Vb, As0, Vdb, St1),
+ Func0 = {function,Name,Arity,St2#cg.fcode,Fun},
+ Func = bs_function(Func0),
+ {Func,St2}.
+
+%% cg_fun([Lkexpr], [HeadVar], Vdb, State) -> {[Ainstr],State}
+
+cg_fun(Les, Hvs, Vdb, St0) ->
+ {Name,Arity} = St0#cg.func,
+ {Fi,St1} = new_label(St0), %FuncInfo label
+ {Fl,St2} = local_func_label(Name, Arity, St1),
+ %% Create initial stack/register state, clear unused arguments.
+ Bef = clear_dead(#sr{reg=foldl(fun ({var,V}, Reg) ->
+ put_reg(V, Reg)
+ end, [], Hvs),
+ stk=[]}, 0, Vdb),
+ {B2,_Aft,St3} = cg_list(Les, 0, Vdb, Bef, St2#cg{btype=exit,
+ bfail=Fi,
+ finfo=Fi,
+ fcode=Fl,
+ is_top_block=true}),
+ A = [{label,Fi},{func_info,{atom,St3#cg.mod},{atom,Name},Arity},
+ {label,Fl}|B2],
+ {A,St3}.
+
+%% cg(Lkexpr, Vdb, StackReg, State) -> {[Ainstr],StackReg,State}.
+%% Generate code for a kexpr.
+%% Split function into two steps for clarity, not efficiency.
+
+cg(Le, Vdb, Bef, St) ->
+ cg(Le#l.ke, Le, Vdb, Bef, St).
+
+cg({block,Es}, Le, Vdb, Bef, St) ->
+ block_cg(Es, Le, Vdb, Bef, St);
+cg({match,M,Rs}, Le, Vdb, Bef, St) ->
+ match_cg(M, Rs, Le, Vdb, Bef, St);
+cg({match_fail,F}, Le, Vdb, Bef, St) ->
+ match_fail_cg(F, Le, Vdb, Bef, St);
+cg({call,Func,As,Rs}, Le, Vdb, Bef, St) ->
+ call_cg(Func, As, Rs, Le, Vdb, Bef, St);
+cg({enter,Func,As}, Le, Vdb, Bef, St) ->
+ enter_cg(Func, As, Le, Vdb, Bef, St);
+cg({bif,Bif,As,Rs}, Le, Vdb, Bef, St) ->
+ bif_cg(Bif, As, Rs, Le, Vdb, Bef, St);
+cg({receive_loop,Te,Rvar,Rm,Tes,Rs}, Le, Vdb, Bef, St) ->
+ recv_loop_cg(Te, Rvar, Rm, Tes, Rs, Le, Vdb, Bef, St);
+cg(receive_next, Le, Vdb, Bef, St) ->
+ recv_next_cg(Le, Vdb, Bef, St);
+cg(receive_accept, _Le, _Vdb, Bef, St) -> {[remove_message],Bef,St};
+cg({'try',Ta,Vs,Tb,Evs,Th,Rs}, Le, Vdb, Bef, St) ->
+ try_cg(Ta, Vs, Tb, Evs, Th, Rs, Le, Vdb, Bef, St);
+cg({'catch',Cb,R}, Le, Vdb, Bef, St) ->
+ catch_cg(Cb, R, Le, Vdb, Bef, St);
+cg({set,Var,Con}, Le, Vdb, Bef, St) -> set_cg(Var, Con, Le, Vdb, Bef, St);
+cg({return,Rs}, Le, Vdb, Bef, St) -> return_cg(Rs, Le, Vdb, Bef, St);
+cg({break,Bs}, Le, Vdb, Bef, St) -> break_cg(Bs, Le, Vdb, Bef, St);
+cg({need_heap,0}, _Le, _Vdb, Bef, St) ->
+ {[],Bef,St};
+cg({need_heap,H}, _Le, _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, I, Vdb, Bef, St0) ->
+ {Keis,{Aft,St1}} =
+ flatmapfoldl(fun (Ke, {Inta,Sta}) ->
+% ok = io:fwrite(" %% ~p\n", [Inta]),
+% ok = io:fwrite("cgl:~p\n", [Ke]),
+ {Keis,Intb,Stb} = cg(Ke, Vdb, Inta, Sta),
+% ok = io:fwrite(" ~p\n", [Keis]),
+% ok = io:fwrite(" %% ~p\n", [Intb]),
+ {comment(Inta) ++ Keis,{Intb,Stb}}
+ end, {Bef,St0}, need_heap(Kes, I)),
+ {Keis,Aft,St1}.
+
+%% need_heap([Lkexpr], I, BifType) -> [Lkexpr].
+%% Insert need_heap instructions in Kexpr list. Try to be smart and
+%% collect them together as much as possible.
+
+need_heap(Kes0, I) ->
+ {Kes1,{H,F}} = flatmapfoldr(fun (Ke, {H0,F0}) ->
+ {Ns,H1,F1} = need_heap_1(Ke, H0, F0),
+ {[Ke|Ns],{H1,F1}}
+ end, {0,false}, Kes0),
+ %% Prepend need_heap if necessary.
+ Kes2 = need_heap_need(I, H, F) ++ Kes1,
+% ok = io:fwrite("need_heap: ~p~n",
+% [{{H,F},
+% map(fun (#l{ke={match,M,Rs}}) -> match;
+% (Lke) -> Lke#l.ke end, Kes2)}]),
+ Kes2.
+
+need_heap_1(#l{ke={set,_,{binary,_}},i=I}, H, F) ->
+ {need_heap_need(I, H, F),0,false};
+need_heap_1(#l{ke={set,_,Val}}, H, F) ->
+ %% Just pass through adding to needed heap.
+ {[],H + case Val of
+ {cons,_} -> 2;
+ {tuple,Es} -> 1 + length(Es);
+ {string,S} -> 2 * length(S);
+ _Other -> 0
+ end,F};
+need_heap_1(#l{ke={call,_Func,_As,_Rs},i=I}, H, F) ->
+ %% Calls generate a need if necessary and also force one.
+ {need_heap_need(I, H, F),0,true};
+need_heap_1(#l{ke={bif,dsetelement,_As,_Rs},i=I}, H, F) ->
+ {need_heap_need(I, H, F),0,true};
+need_heap_1(#l{ke={bif,{make_fun,_,_,_,_},_As,_Rs},i=I}, H, F) ->
+ {need_heap_need(I, H, F),0,true};
+need_heap_1(#l{ke={bif,_Bif,_As,_Rs}}, H, F) ->
+ {[],H,F};
+need_heap_1(#l{i=I}, H, F) ->
+ %% Others kexprs generate a need if necessary but don't force.
+ {need_heap_need(I, H, F),0,false}.
+
+need_heap_need(_I, 0, false) -> [];
+need_heap_need(I, H, _F) -> [#l{ke={need_heap,H},i=I}].
+
+
+%% match_cg(Match, [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.
+%% Should test this.
+
+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, none, 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}}.
+
+%% 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(Le, Fail, Bef, St) ->
+ match_cg(Le#l.ke, Le, Fail, Bef, St).
+
+match_cg({alt,F,S}, _Le, 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({select,V,Scs}, _Va, Fail, Bef, St) ->
+ match_fmf(fun (S, F, Sta) ->
+ select_cg(S, V, F, Fail, Bef, Sta) end,
+ Fail, St, Scs);
+match_cg({guard,Gcs}, _Le, Fail, Bef, St) ->
+ match_fmf(fun (G, F, Sta) -> guard_clause_cg(G, F, Bef, Sta) end,
+ Fail, St, Gcs);
+match_cg({block,Es}, Le, _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).
+
+%% match_fail_cg(FailReason, Le, Vdb, StackReg, State) ->
+%% {[Ainstr],StackReg,State}.
+%% Generate code for the match_fail "call". N.B. there is no generic
+%% case for when the fail value has been created elsewhere.
+
+match_fail_cg({function_clause,As}, Le, Vdb, Bef, St) ->
+ %% Must have the args in {x,0}, {x,1},...
+ {Sis,Int} = cg_setup_call(As, Bef, Le#l.i, Vdb),
+ {Sis ++ [{jump,{f,St#cg.finfo}}],
+ Int#sr{reg=clear_regs(Int#sr.reg)},St};
+match_fail_cg({badmatch,Term}, Le, Vdb, Bef, St) ->
+ R = cg_reg_arg(Term, Bef),
+ Int0 = clear_dead(Bef, Le#l.i, Vdb),
+ {Sis,Int} = adjust_stack(Int0, Le#l.i, Le#l.i+1, Vdb),
+ {Sis ++ [{badmatch,R}],
+ Int#sr{reg=clear_regs(Int0#sr.reg)},St};
+match_fail_cg({case_clause,Reason}, Le, Vdb, Bef, St) ->
+ R = cg_reg_arg(Reason, Bef),
+ Int0 = clear_dead(Bef, Le#l.i, Vdb),
+ {Sis,Int} = adjust_stack(Int0, Le#l.i, Le#l.i+1, Vdb),
+ {Sis++[{case_end,R}],
+ Int#sr{reg=clear_regs(Bef#sr.reg)},St};
+match_fail_cg(if_clause, Le, Vdb, Bef, St) ->
+ Int0 = clear_dead(Bef, Le#l.i, Vdb),
+ {Sis,Int1} = adjust_stack(Int0, Le#l.i, Le#l.i+1, Vdb),
+ {Sis++[if_end],Int1#sr{reg=clear_regs(Int1#sr.reg)},St};
+match_fail_cg({try_clause,Reason}, Le, Vdb, Bef, St) ->
+ R = cg_reg_arg(Reason, Bef),
+ Int0 = clear_dead(Bef, Le#l.i, Vdb),
+ {Sis,Int} = adjust_stack(Int0, Le#l.i, Le#l.i+1, Vdb),
+ {Sis ++ [{try_case_end,R}],
+ Int#sr{reg=clear_regs(Int0#sr.reg)},St}.
+
+
+%% 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, St0) ->
+ case St0#cg.is_top_block of
+ false ->
+ cg_block(Es, Le#l.i, Le#l.vdb, Bef, St0);
+ true ->
+ {Keis,Aft,St1} = cg_block(Es, Le#l.i, Le#l.vdb, Bef,
+ St0#cg{is_top_block=false,
+ need_frame=false}),
+ top_level_block(Keis, Aft, max_reg(Bef#sr.reg), St1)
+ end.
+
+cg_block([], _I, _Vdb, Bef, St0) ->
+ {[],Bef,St0};
+cg_block(Kes0, I, Vdb, Bef, St0) ->
+ {Kes2,Int1,St1} =
+ case basic_block(Kes0) of
+ {Kes1,LastI,Args,Rest} ->
+ Ke = hd(Kes1),
+ Fb = Ke#l.i,
+ cg_basic_block(Kes1, Fb, LastI, Args, Vdb, Bef, St0);
+ {Kes1,Rest} ->
+ cg_list(Kes1, I, Vdb, Bef, St0)
+ end,
+ {Kes3,Int2,St2} = cg_block(Rest, I, Vdb, Int1, St1),
+ {Kes2 ++ Kes3,Int2,St2}.
+
+basic_block(Kes) -> basic_block(Kes, []).
+
+basic_block([], Acc) -> {reverse(Acc),[]};
+basic_block([Le|Les], Acc) ->
+ case collect_block(Le#l.ke) of
+ include -> basic_block(Les, [Le|Acc]);
+ {block_end,As} -> {reverse(Acc, [Le]),Le#l.i,As,Les};
+ no_block -> {reverse(Acc, [Le]),Les}
+ end.
+
+collect_block({set,_,{binary,_}}) -> no_block;
+collect_block({set,_,_}) -> include;
+collect_block({call,{var,_}=Var,As,_Rs}) -> {block_end,As++[Var]};
+collect_block({call,Func,As,_Rs}) -> {block_end,As++func_vars(Func)};
+collect_block({enter,{var,_}=Var,As})-> {block_end,As++[Var]};
+collect_block({enter,Func,As}) -> {block_end,As++func_vars(Func)};
+collect_block({return,Rs}) -> {block_end,Rs};
+collect_block({break,Bs}) -> {block_end,Bs};
+collect_block({bif,_Bif,_As,_Rs}) -> include;
+collect_block(_) -> no_block.
+
+func_vars({remote,M,F}) when element(1, M) == var;
+ element(1, F) == var ->
+ [M,F];
+func_vars(_) -> [].
+
+%% cg_basic_block([Kexpr], FirstI, LastI, As, Vdb, StackReg, State) ->
+%% {[Ainstr],StackReg,State}.
+
+cg_basic_block(Kes, Fb, Lf, As, Vdb, Bef, St0) ->
+ Res = make_reservation(As, 0),
+ Regs0 = reserve(Res, Bef#sr.reg, Bef#sr.stk),
+ Stk = extend_stack(Bef, Lf, Lf+1, Vdb),
+ Int0 = Bef#sr{reg=Regs0,stk=Stk,res=Res},
+ X0_v0 = x0_vars(As, Fb, Lf, Vdb),
+ {Keis,{Aft,_,St1}} =
+ flatmapfoldl(fun(Ke, St) -> cg_basic_block(Ke, St, Lf, Vdb) end,
+ {Int0,X0_v0,St0}, need_heap(Kes, Fb)),
+ {Keis,Aft,St1}.
+
+cg_basic_block(Ke, {Inta,X0v,Sta}, _Lf, Vdb) when element(1, Ke#l.ke) =:= need_heap ->
+ {Keis,Intb,Stb} = cg(Ke, Vdb, Inta, Sta),
+ {comment(Inta) ++ Keis, {Intb,X0v,Stb}};
+cg_basic_block(Ke, {Inta,X0_v1,Sta}, Lf, Vdb) ->
+ {Sis,Intb} = save_carefully(Inta, Ke#l.i, Lf+1, Vdb),
+ {X0_v2,Intc} = allocate_x0(X0_v1, Ke#l.i, Intb),
+ Intd = reserve(Intc),
+ {Keis,Inte,Stb} = cg(Ke, Vdb, Intd, Sta),
+ {comment(Inta) ++ Sis ++ Keis, {Inte,X0_v2,Stb}}.
+
+make_reservation([], _) -> [];
+make_reservation([{var,V}|As], I) -> [{I,V}|make_reservation(As, I+1)];
+make_reservation([A|As], I) -> [{I,A}|make_reservation(As, I+1)].
+
+reserve(Sr) -> Sr#sr{reg=reserve(Sr#sr.res, Sr#sr.reg, Sr#sr.stk)}.
+
+reserve([{I,V}|Rs], [free|Regs], Stk) -> [{reserved,I,V}|reserve(Rs, Regs, Stk)];
+reserve([{I,V}|Rs], [{I,V}|Regs], Stk) -> [{I,V}|reserve(Rs, Regs, Stk)];
+reserve([{I,V}|Rs], [{I,Var}|Regs], Stk) ->
+ case on_stack(Var, Stk) of
+ true -> [{reserved,I,V}|reserve(Rs, Regs, Stk)];
+ false -> [{I,Var}|reserve(Rs, Regs, Stk)]
+ end;
+reserve([{I,V}|Rs], [{reserved,I,_}|Regs], Stk) ->
+ [{reserved,I,V}|reserve(Rs, Regs, Stk)];
+%reserve([{I,V}|Rs], [Other|Regs], Stk) -> [Other|reserve(Rs, Regs, Stk)];
+reserve([{I,V}|Rs], [], Stk) -> [{reserved,I,V}|reserve(Rs, [], Stk)];
+reserve([], Regs, _) -> Regs.
+
+extend_stack(Bef, Fb, Lf, Vdb) ->
+ Stk0 = clear_dead_stk(Bef#sr.stk, Fb, Vdb),
+ Saves = [V || {V,F,L} <- Vdb,
+ F < Fb,
+ L >= Lf,
+ not on_stack(V, Stk0)],
+ Stk1 = foldl(fun (V, Stk) -> put_stack(V, Stk) end, Stk0, Saves),
+ Bef#sr.stk ++ lists:duplicate(length(Stk1) - length(Bef#sr.stk), free).
+
+save_carefully(Bef, Fb, Lf, Vdb) ->
+ Stk = Bef#sr.stk,
+ %% New variables that are in use but not on stack.
+ New = [ {V,F,L} || {V,F,L} <- Vdb,
+ F < Fb,
+ L >= Lf,
+ not on_stack(V, Stk) ],
+ Saves = [ V || {V,_,_} <- keysort(2, New) ],
+ save_carefully(Saves, Bef, []).
+
+save_carefully([], Bef, Acc) -> {reverse(Acc),Bef};
+save_carefully([V|Vs], Bef, Acc) ->
+ case put_stack_carefully(V, Bef#sr.stk) of
+ error -> {reverse(Acc),Bef};
+ Stk1 ->
+ SrcReg = fetch_reg(V, Bef#sr.reg),
+ Move = {move,SrcReg,fetch_stack(V, Stk1)},
+ {x,_} = SrcReg, %Assertion - must be X register.
+ save_carefully(Vs, Bef#sr{stk=Stk1}, [Move|Acc])
+ end.
+
+x0_vars([], _Fb, _Lf, _Vdb) -> [];
+x0_vars([{var,V}|_], Fb, _Lf, Vdb) ->
+ {V,F,_L} = VFL = vdb_find(V, Vdb),
+ x0_vars1([VFL], Fb, F, Vdb);
+x0_vars([X0|_], Fb, Lf, Vdb) ->
+ x0_vars1([{X0,Lf,Lf}], Fb, Lf, Vdb).
+
+x0_vars1(X0, Fb, Xf, Vdb) ->
+ Vs0 = [VFL || {_V,F,L}=VFL <- Vdb,
+ F >= Fb,
+ L < Xf],
+ Vs1 = keysort(3, Vs0),
+ keysort(2, X0++Vs1).
+
+allocate_x0([], _, Bef) -> {[],Bef#sr{res=[]}};
+allocate_x0([{_,_,L}|Vs], I, Bef) when L =< I ->
+ allocate_x0(Vs, I, Bef);
+allocate_x0([{V,_F,_L}=VFL|Vs], _, Bef) ->
+ {[VFL|Vs],Bef#sr{res=reserve_x0(V, Bef#sr.res)}}.
+
+reserve_x0(V, [_|Res]) -> [{0,V}|Res];
+reserve_x0(V, []) -> [{0,V}].
+
+top_level_block(Keis, Bef, _MaxRegs, St0) when St0#cg.need_frame =:= false,
+ length(Bef#sr.stk) =:= 0 ->
+ %% This block need no stack frame. However, we still need to turn the
+ %% stack frame upside down.
+ MaxY = length(Bef#sr.stk)-1,
+ Keis1 = flatmap(fun (Tuple) when tuple(Tuple) ->
+ [turn_yregs(size(Tuple), Tuple, MaxY)];
+ (Other) ->
+ [Other]
+ end, Keis),
+ {Keis1, Bef, St0#cg{is_top_block=true}};
+top_level_block(Keis, Bef, MaxRegs, St0) ->
+ %% 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 tuple(Tuple) ->
+ [turn_yregs(size(Tuple), Tuple, MaxY)];
+ (Other) ->
+ [Other]
+ end, Keis),
+ {[{allocate_zero,FrameSz,MaxRegs}|Keis1], Bef, St0#cg{is_top_block=true}}.
+
+%% 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(0, Tp, _) -> Tp;
+turn_yregs(El, Tp, MaxY) when element(1, element(El, Tp)) == yy ->
+ turn_yregs(El-1, setelement(El, Tp, {y,MaxY-element(2, element(El, Tp))}), MaxY);
+turn_yregs(El, Tp, MaxY) when list(element(El, Tp)) ->
+ New = map(fun ({yy,YY}) -> {y,MaxY-YY};
+ (Other) -> Other end, element(El, Tp)),
+ turn_yregs(El-1, setelement(El, Tp, New), MaxY);
+turn_yregs(El, Tp, MaxY) ->
+ turn_yregs(El-1, Tp, MaxY).
+
+%% 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(#l{ke={type_clause,cons,[S]}}, {var,V}, Tf, Vf, Bef, St) ->
+ select_cons(S, V, Tf, Vf, Bef, St);
+select_cg(#l{ke={type_clause,nil,[S]}}, {var,V}, Tf, Vf, Bef, St) ->
+ select_nil(S, V, Tf, Vf, Bef, St);
+select_cg(#l{ke={type_clause,binary,[S]}}, {var,V}, Tf, Vf, Bef, St) ->
+ select_binary(S, V, Tf, Vf, Bef, St);
+select_cg(#l{ke={type_clause,bin_seg,S}}, {var,V}, Tf, Vf, Bef, St) ->
+ select_bin_segs(S, V, Tf, Vf, Bef, St);
+select_cg(#l{ke={type_clause,bin_end,[S]}}, {var,V}, Tf, Vf, Bef, St) ->
+ select_bin_end(S, V, Tf, Vf, Bef, St);
+select_cg(#l{ke={type_clause,Type,Scs}}, {var,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(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(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,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,Val}]}|Sis];
+select_val_cg(Type, R, Vls0, Tf, Vf, Sis) ->
+ Vls1 = map(fun ({f,Lbl}) -> {f,Lbl};
+ (Value) -> {Type,Value}
+ end, Vls0),
+ [{test,select_type_test(Type),{f,Tf},[R]}, {select_val,R,{f,Vf},{list,Vls1}}|Sis].
+
+select_type_test(tuple) -> is_tuple;
+select_type_test(integer) -> is_integer;
+select_type_test(atom) -> is_atom;
+select_type_test(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_cons(#l{ke={val_clause,{cons,Es},B},i=I,vdb=Vdb}, V, Tf, Vf, Bef, St0) ->
+ {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(#l{ke={val_clause,nil,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(#l{ke={val_clause,{old_binary,Var},B}}=L,
+ V, Tf, Vf, Bef, St) ->
+ %% Currently handled in the same way as new binaries.
+ select_binary(L#l{ke={val_clause,{binary,Var},B}}, V, Tf, Vf, Bef, St);
+select_binary(#l{ke={val_clause,{binary,{var,Ivar}},B},i=I,vdb=Vdb},
+ V, Tf, Vf, Bef, St0) ->
+ Int0 = clear_dead(Bef, I, Vdb),
+ {Bis,Aft,St1} = match_cg(B, Vf, Int0, St0),
+ {[{test,bs_start_match,{f,Tf},[fetch_var(V, Bef)]},{bs_save,Ivar}|Bis],
+ Aft,St1}.
+
+select_bin_segs(Scs, Ivar, Tf, _Vf, Bef, St) ->
+ match_fmf(fun(S, Fail, Sta) ->
+ select_bin_seg(S, Ivar, Fail, Bef, Sta) end,
+ Tf, St, Scs).
+
+select_bin_seg(#l{ke={val_clause,{bin_seg,Size,U,T,Fs,Es},B},i=I,vdb=Vdb},
+ Ivar, Fail, Bef, St0) ->
+ {Mis,Int,St1} = select_extract_bin(Es, Size, U, T, Fs, Fail,
+ I, Vdb, Bef, St0),
+ {Bis,Aft,St2} = match_cg(B, Fail, Int, St1),
+ {[{bs_restore,Ivar}|Mis] ++ Bis,Aft,St2}.
+
+select_extract_bin([{var,Hd},{var,Tl}], Size0, Unit, Type, Flags, Vf,
+ I, Vdb, Bef, St) ->
+ SizeReg = get_bin_size_reg(Size0, Bef),
+ {Es,Aft} =
+ case vdb_find(Hd, Vdb) of
+ {_,_,Lhd} when Lhd =< I ->
+ {[{test,bs_skip_bits,{f,Vf},[SizeReg,Unit,{field_flags,Flags}]},
+ {bs_save,Tl}],Bef};
+ {_,_,_} ->
+ Reg0 = put_reg(Hd, Bef#sr.reg),
+ Int1 = Bef#sr{reg=Reg0},
+ Rhd = fetch_reg(Hd, Reg0),
+ Name = get_bits_instr(Type),
+ {[{test,Name,{f,Vf},[SizeReg,Unit,{field_flags,Flags},Rhd]},
+ {bs_save,Tl}],Int1}
+ end,
+ {Es,clear_dead(Aft, I, Vdb),St}.
+
+get_bin_size_reg({var,V}, Bef) ->
+ fetch_var(V, Bef);
+get_bin_size_reg(Literal, _Bef) ->
+ Literal.
+
+select_bin_end(#l{ke={val_clause,bin_end,B}},
+ Ivar, Tf, Vf, Bef, St0) ->
+ {Bis,Aft,St2} = match_cg(B, Vf, Bef, St0),
+ {[{bs_restore,Ivar},{test,bs_test_tail,{f,Tf},[0]}|Bis],Aft,St2}.
+
+get_bits_instr(integer) -> bs_get_integer;
+get_bits_instr(float) -> bs_get_float;
+get_bits_instr(binary) -> bs_get_binary.
+
+select_val(#l{ke={val_clause,{tuple,Es},B},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(#l{ke={val_clause,{_,Val},B}}, _V, Vf, Bef, St0) ->
+ {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 ({var,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_extract_cons(Src, [{var,Hd}, {var,Tl}], I, Vdb, Bef, St) ->
+ {Es,Aft} = case {vdb_find(Hd, Vdb), vdb_find(Tl, Vdb)} of
+ {{_,_,Lhd}, {_,_,Ltl}} when Lhd =< I, Ltl =< I ->
+ %% Both head and tail are dead. No need to generate
+ %% any instruction.
+ {[], Bef};
+ _ ->
+ %% At least one of head and tail will be used,
+ %% but we must always fetch both. We will call
+ %% clear_dead/2 to allow reuse of the register
+ %% in case only of them is used.
+
+ Reg0 = put_reg(Tl, put_reg(Hd, Bef#sr.reg)),
+ Int0 = Bef#sr{reg=Reg0},
+ Rsrc = fetch_var(Src, Int0),
+ Rhd = fetch_reg(Hd, Reg0),
+ Rtl = fetch_reg(Tl, Reg0),
+ Int1 = clear_dead(Int0, I, Vdb),
+ {[{get_list,Rsrc,Rhd,Rtl}], Int1}
+ end,
+ {Es,Aft,St}.
+
+
+guard_clause_cg(#l{ke={guard_clause,G,B},vdb=Vdb}, Fail, Bef, St0) ->
+ {Gis,Int,St1} = guard_cg(G, Fail, Vdb, Bef, St0),
+ {Bis,Aft,St2} = match_cg(B, Fail, Int, St1),
+ {Gis ++ Bis,Aft,St2}.
+
+%% 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(#l{ke={protected,Ts,Rs},i=I,vdb=Pdb}, Fail, _Vdb, Bef, St) ->
+ protected_cg(Ts, Rs, Fail, I, Pdb, Bef, St);
+guard_cg(#l{ke={block,Ts},i=I,vdb=Bdb}, Fail, _Vdb, Bef, St) ->
+ guard_cg_list(Ts, Fail, I, Bdb, Bef, St);
+guard_cg(#l{ke={test,Test,As},i=I,vdb=_Tdb}, Fail, Vdb, Bef, St) ->
+ test_cg(Test, As, Fail, I, Vdb, Bef, St);
+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}.
+
+%% 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, I, Vdb, Bef, St0) ->
+ %% Protect these calls, revert when done.
+ {Tis,Aft,St1} = guard_cg_list(Ts, Fail, I, Vdb, Bef,
+ St0#cg{btype=fail,bfail=Fail}),
+ {Tis,Aft,St1#cg{btype=St0#cg.btype,bfail=St0#cg.bfail}};
+protected_cg(Ts, Rs, _Fail, I, Vdb, Bef, St0) ->
+ {Pfail,St1} = new_label(St0),
+ {Psucc,St2} = new_label(St1),
+ {Tis,Aft,St3} = guard_cg_list(Ts, Pfail, I, Vdb, Bef,
+ St2#cg{btype=fail,bfail=Pfail}),
+ %%ok = io:fwrite("cg ~w: ~p~n", [?LINE,{Rs,I,Vdb,Aft}]),
+ %% Set return values to false.
+ Mis = map(fun ({var,V}) -> {move,{atom,false},fetch_var(V, Aft)} end, Rs),
+ Live = {'%live',max_reg(Aft#sr.reg)},
+ {Tis ++ [Live,{jump,{f,Psucc}},
+ {label,Pfail}] ++ Mis ++ [Live,{label,Psucc}],
+ Aft,St3#cg{btype=St0#cg.btype,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(Test, As, Fail, I, Vdb, Bef, St) ->
+ case test_type(Test, length(As)) of
+ {cond_op,Op} ->
+ Ars = cg_reg_args(As, Bef),
+ Int = clear_dead(Bef, I, Vdb),
+ {[{test,Op,{f,Fail},Ars}],
+ clear_dead(Int, I, Vdb),
+ St};
+ {rev_cond_op,Op} ->
+ [S1,S2] = cg_reg_args(As, Bef),
+ Int = clear_dead(Bef, I, Vdb),
+ {[{test,Op,{f,Fail},[S2,S1]}],
+ clear_dead(Int, I, Vdb),
+ St}
+ end.
+
+test_type(is_atom, 1) -> {cond_op,is_atom};
+test_type(is_boolean, 1) -> {cond_op,is_boolean};
+test_type(is_binary, 1) -> {cond_op,is_binary};
+test_type(is_constant, 1) -> {cond_op,is_constant};
+test_type(is_float, 1) -> {cond_op,is_float};
+test_type(is_function, 1) -> {cond_op,is_function};
+test_type(is_integer, 1) -> {cond_op,is_integer};
+test_type(is_list, 1) -> {cond_op,is_list};
+test_type(is_number, 1) -> {cond_op,is_number};
+test_type(is_pid, 1) -> {cond_op,is_pid};
+test_type(is_port, 1) -> {cond_op,is_port};
+test_type(is_reference, 1) -> {cond_op,is_reference};
+test_type(is_tuple, 1) -> {cond_op,is_tuple};
+test_type('=<', 2) -> {rev_cond_op,is_ge};
+test_type('>', 2) -> {rev_cond_op,is_lt};
+test_type('<', 2) -> {cond_op,is_lt};
+test_type('>=', 2) -> {cond_op,is_ge};
+test_type('==', 2) -> {cond_op,is_eq};
+test_type('/=', 2) -> {cond_op,is_ne};
+test_type('=:=', 2) -> {cond_op,is_eq_exact};
+test_type('=/=', 2) -> {cond_op,is_ne_exact};
+test_type(internal_is_record, 3) -> {cond_op,internal_is_record}.
+
+%% guard_cg_list([Kexpr], Fail, I, Vdb, StackReg, St) ->
+%% {[Ainstr],StackReg,St}.
+
+guard_cg_list(Kes, Fail, I, Vdb, Bef, St0) ->
+ {Keis,{Aft,St1}} =
+ flatmapfoldl(fun (Ke, {Inta,Sta}) ->
+ {Keis,Intb,Stb} =
+ guard_cg(Ke, Fail, Vdb, Inta, Sta),
+ {comment(Inta) ++ Keis,{Intb,Stb}}
+ end, {Bef,St0}, need_heap(Kes, I)),
+ {Keis,Aft,St1}.
+
+%% 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};
+match_fmf(_, _, St, []) -> {[],void,St}.
+
+%% 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({var,V}, As, Rs, Le, Vdb, Bef, St0) ->
+ {Sis,Int} = cg_setup_call(As++[{var,V}], 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)),
+ {comment({call_fun,{var,V},As}) ++ Sis ++ Frees ++ [{call_fun,Arity}],
+ Aft,need_stack_frame(St0)};
+call_cg({remote,Mod,Name}, As, Rs, Le, Vdb, Bef, St0)
+ when element(1, Mod) == var;
+ element(1, Name) == 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),
+ Call = {apply,Arity},
+ 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 ++ [Call],Aft,St};
+call_cg(Func, As, Rs, Le, Vdb, Bef, St0) ->
+ {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)),
+ {comment({call,Func,As}) ++ Sis ++ Frees ++ Call,Aft,St1}.
+
+build_call({remote,{atom,erlang},{atom,'!'}}, 2, St0) ->
+ {[send],need_stack_frame(St0)};
+build_call({remote,{atom,Mod},{atom,Name}}, Arity, St0) ->
+ {[{call_ext,Arity,{extfunc,Mod,Name,Arity}}],need_stack_frame(St0)};
+build_call(Name, Arity, St0) when 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({var,V}, As, Le, Vdb, Bef, St0) ->
+ {Sis,Int} = cg_setup_call(As++[{var,V}], Bef, Le#l.i, Vdb),
+ %% Build complete code and final stack/register state.
+ Arity = length(As),
+ {comment({call_fun,{var,V},As}) ++ Sis ++ [{call_fun,Arity},return],
+ clear_dead(Int#sr{reg=clear_regs(Int#sr.reg)}, Le#l.i, Vdb),
+ need_stack_frame(St0)};
+enter_cg({remote,Mod,Name}=Func, As, Le, Vdb, Bef, St0)
+ when element(1, Mod) == var;
+ element(1, Name) == 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),
+ Call = {apply_only,Arity},
+ St = need_stack_frame(St0),
+ {comment({enter,Func,As}) ++ Sis ++ [Call],
+ 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),
+ {comment({enter,Func,As}) ++ Sis ++ Call,
+ clear_dead(Int#sr{reg=clear_regs(Int#sr.reg)}, Le#l.i, Vdb),
+ St1}.
+
+build_enter({remote,{atom,erlang},{atom,'!'}}, 2, St0) ->
+ {[send,return],need_stack_frame(St0)};
+build_enter({remote,{atom,Mod},{atom,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(Name, Arity, St0) when is_atom(Name) ->
+ {Lbl,St1} = local_func_label(Name, Arity, St0),
+ {[{call_only,Arity,{f,Lbl}}],St1}.
+
+%% local_func_label(Name, Arity, State) -> {Label,State'}
+%% Get the function entry label for a local function.
+
+local_func_label(Name, Arity, St0) ->
+ Key = {Name,Arity},
+ case keysearch(Key, 1, St0#cg.functable) of
+ {value,{Key,Label}} ->
+ {Label,St0};
+ false ->
+ {Label,St1} = new_label(St0),
+ {Label,St1#cg{functable=[{Key,Label}|St1#cg.functable]}}
+ 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, '!', 2) -> true;
+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(Bif, [Arg], [Ret], Le, Vdb, StackReg, State) ->
+%% {[Ainstr],StackReg,State}.
+
+bif_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};
+bif_cg({make_fun,Func,Arity,Index,Uniq}, As, Rs, Le, Vdb, Bef, St0) ->
+ %% This behaves more like a function call.
+ {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 = case St0#cg.new_funs of
+ true -> {make_fun2,{f,FuncLbl},Index,Uniq,length(As)};
+ false -> {make_fun,{f,FuncLbl},Uniq,length(As)}
+ end,
+ {comment({make_fun,{Func,Arity,Uniq},As}) ++ Sis ++
+ [MakeFun],
+ clear_dead(Int#sr{reg=Reg}, Le#l.i, Vdb),
+ St1};
+bif_cg(Bif, As, [{var,V}], Le, Vdb, Bef, St0) ->
+ Ars = cg_reg_args(As, Bef),
+
+ %% If we are inside a catch, we must save everything that will
+ %% be alive after the catch (because the BIF might fail and there
+ %% will be a jump to the code after the catch).
+ %% Currently, we are somewhat pessimistic in
+ %% that we save any variable that will be live after this BIF call.
+
+ {Sis,Int0} =
+ case St0#cg.in_catch of
+ true -> adjust_stack(Bef, Le#l.i, Le#l.i+1, Vdb);
+ 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),
+ {Sis ++ [{bif,Bif,bif_fail(St0#cg.btype, St0#cg.bfail, length(Ars)),Ars,Dst}],
+ clear_dead(Int, Le#l.i, Vdb), St0}.
+
+bif_fail(_, _, 0) -> nofail;
+bif_fail(exit, _, _) -> {f,0};
+bif_fail(fail, Fail, _) -> {f,Fail}.
+
+%% 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 ++ 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({var,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),
+ {[{'%live',0},{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({atom,infinity}, 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, Tes#l.vdb),
+ {_,Int2,St1} = cg_block(Tes#l.ke, Tes#l.i, Tes#l.vdb,
+ Int1#sr{reg=clear_regs(Int1#sr.reg)}, St0),
+ {[{wait,{f,St1#cg.recv}}],Int2,St1};
+cg_recv_wait({integer,0}, Tes, _I, Bef, St0) ->
+ {Tis,Int,St1} = cg_block(Tes#l.ke, Tes#l.i, Tes#l.vdb, Bef, St0),
+ {[timeout|Tis],Int,St1};
+cg_recv_wait(Te, 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, Tes#l.vdb),
+ {Tis,Int,St1} = cg_block(Tes#l.ke, Tes#l.i, Tes#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
+ TryTag = Ta#l.i,
+ 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}}.
+
+%% catch_cg(CatchBlock, Ret, Le, Vdb, Bef, St) -> {[Ainstr],Aft,St}.
+
+catch_cg(C, {var,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.i, Le#l.vdb, Int1,
+ St1#cg{break=B,in_catch=true}),
+ Aft = Int2#sr{reg=load_reg(R, 0, Int2#sr.reg),
+ 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}}.
+
+%% set_cg([Var], Constr, Le, Vdb, Bef, St) -> {[Ainstr],Aft,St}.
+%% We have to be careful how a 'set' 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 for constructing a cons is an atomic instruction
+%% which can safely resuse one of the source registers as target.
+%% Also binaries can reuse a source register as target.
+
+set_cg([{var,R}], {cons,Es}, Le, Vdb, Bef, St) ->
+ [S1,S2] = map(fun ({var,V}) -> fetch_var(V, Bef);
+ (Other) -> Other
+ end, Es),
+ 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};
+set_cg([{var,R}], {old_binary,Segs}, Le, Vdb, Bef, St) ->
+ Fail = bif_fail(St#cg.btype, St#cg.bfail, 42),
+ PutCode = cg_bin_put(Segs, Fail, Bef),
+ Code = cg_binary_old(PutCode),
+ Int0 = clear_dead(Bef, Le#l.i, Vdb),
+ Aft = Int0#sr{reg=put_reg(R, Int0#sr.reg)},
+ Ret = fetch_reg(R, Aft#sr.reg),
+ {Code ++ [{bs_final,Fail,Ret}],Aft,St};
+set_cg([{var,R}], {binary,Segs}, Le, Vdb, Bef, #cg{in_catch=InCatch}=St) ->
+ Int0 = Bef#sr{reg=put_reg(R, Bef#sr.reg)},
+ Target = fetch_reg(R, Int0#sr.reg),
+ Fail = bif_fail(St#cg.btype, St#cg.bfail, 42),
+ Temp = find_scratch_reg(Int0#sr.reg),
+ PutCode = cg_bin_put(Segs, Fail, Bef),
+ {Sis,Int1} =
+ case InCatch of
+ true -> adjust_stack(Int0, Le#l.i, Le#l.i+1, Vdb);
+ false -> {[],Int0}
+ end,
+ Aft = clear_dead(Int1, Le#l.i, Vdb),
+ Code = cg_binary(PutCode, Target, Temp, Fail, Aft),
+ {Sis++Code,Aft,St};
+set_cg([{var,R}], Con, Le, Vdb, Bef, St) ->
+ %% Find a place for the return register first.
+ Int = Bef#sr{reg=put_reg(R, Bef#sr.reg)},
+ Ret = fetch_reg(R, Int#sr.reg),
+ Ais = case Con of
+ {tuple,Es} ->
+ [{put_tuple,length(Es),Ret}] ++ cg_build_args(Es, Bef);
+ {var,V} -> % Normally removed by kernel optimizer.
+ [{move,fetch_var(V, Int),Ret}];
+ {string,Str} ->
+ [{put_string,length(Str),{string,Str},Ret}];
+ Other ->
+ [{move,Other,Ret}]
+ end,
+ {Ais,clear_dead(Int, Le#l.i, Vdb),St};
+set_cg([], {binary,Segs}, Le, Vdb, Bef, St) ->
+ Fail = bif_fail(St#cg.btype, St#cg.bfail, 42),
+ Target = find_scratch_reg(Bef#sr.reg),
+ Temp = find_scratch_reg(put_reg(Target, Bef#sr.reg)),
+ PutCode = cg_bin_put(Segs, Fail, Bef),
+ Code = cg_binary(PutCode, Target, Temp, Fail, Bef),
+ Aft = clear_dead(Bef, Le#l.i, Vdb),
+ {Code,Aft,St};
+set_cg([], {old_binary,Segs}, Le, Vdb, Bef, St) ->
+ Fail = bif_fail(St#cg.btype, St#cg.bfail, 42),
+ PutCode = cg_bin_put(Segs, Fail, Bef),
+ Ais0 = cg_binary_old(PutCode),
+ Ret = find_scratch_reg(Bef#sr.reg),
+ Ais = Ais0 ++ [{bs_final,Fail,Ret}],
+ {Ais,clear_dead(Bef, Le#l.i, Vdb),St};
+set_cg([], _, Le, Vdb, Bef, St) ->
+ %% This should have been stripped by compiler, just cleanup.
+ {[],clear_dead(Bef, Le#l.i, Vdb), St}.
+
+
+%%%
+%%% Code generation for constructing binaries.
+%%%
+
+cg_binary(PutCode, Target, Temp, Fail, Bef) ->
+ SzCode = cg_binary_size(PutCode, Target, Temp, Fail),
+ MaxRegs = max_reg(Bef#sr.reg),
+ Code = SzCode ++ [{bs_init2,Fail,Target,MaxRegs,{field_flags,[]},Target}|PutCode],
+ cg_bin_opt(Code).
+
+cg_binary_size(PutCode, Target, Temp, Fail) ->
+ Szs = cg_binary_size_1(PutCode, 0, []),
+ cg_binary_size_expr(Szs, Target, Temp, Fail).
+
+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,
+ Res = sort([{1,{integer,RemBits}},{8,{integer,Bytes}}|Acc]),
+ cg_binary_size_3(Res).
+
+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}, 8, E, Next, Bits, Acc) ->
+ cg_binary_size_1(Next, Bits, [{8,{size,E}}|Acc]);
+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_size_3([{_,{integer,0}}|T]) ->
+ cg_binary_size_3(T);
+cg_binary_size_3([{U,S1},{U,S2}|T]) ->
+ {L0,Rest} = cg_binary_size_4(T, U, []),
+ L = [S1,S2|L0],
+ [{U,L}|cg_binary_size_3(Rest)];
+cg_binary_size_3([{U,S}|T]) ->
+ [{U,[S]}|cg_binary_size_3(T)];
+cg_binary_size_3([]) -> [].
+
+cg_binary_size_4([{U,S}|T], U, Acc) ->
+ cg_binary_size_4(T, U, [S|Acc]);
+cg_binary_size_4(T, _, Acc) ->
+ {Acc,T}.
+
+%% cg_binary_size_expr/4
+%% Generate code for calculating the resulting size of a binary.
+cg_binary_size_expr(Sizes, Target, Temp, Fail) ->
+ cg_binary_size_expr_1(Sizes, Target, Temp, Fail,
+ [{move,{integer,0},Target}]).
+
+cg_binary_size_expr_1([{1,E0}|T], Target, Temp, Fail, Acc) ->
+ E1 = cg_gen_binsize(E0, Target, Temp, Fail, Acc),
+ E = [{bs_bits_to_bytes,Fail,Target,Target}|E1],
+ cg_binary_size_expr_1(T, Target, Temp, Fail, E);
+cg_binary_size_expr_1([{8,E0}], Target, Temp, Fail, Acc) ->
+ E = cg_gen_binsize(E0, Target, Temp, Fail, Acc),
+ reverse(E);
+cg_binary_size_expr_1([], _, _, _, Acc) -> reverse(Acc).
+
+cg_gen_binsize([{'*',A,B}|T], Target, Temp, Fail, Acc) ->
+ cg_gen_binsize(T, Target, Temp, Fail,
+ [{bs_add,Fail,[Target,A,B],Target}|Acc]);
+cg_gen_binsize([{size,B}|T], Target, Temp, Fail, Acc) ->
+ cg_gen_binsize([Temp|T], Target, Temp, Fail,
+ [{bif,size,Fail,[B],Temp}|Acc]);
+cg_gen_binsize([E0|T], Target, Temp, Fail, Acc) ->
+ cg_gen_binsize(T, Target, Temp, Fail,
+ [{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,{integer,0},D},{bs_add,_,[D,{integer,_}=S,1],Dst}|Is]) ->
+ cg_bin_opt([{move,S,Dst}|Is]);
+cg_bin_opt([{move,{integer,0},D},{bs_add,Fail,[D,S,U],Dst}|Is]) ->
+ cg_bin_opt([{bs_add,Fail,[{integer,0},S,U],Dst}|Is]);
+cg_bin_opt([{move,{integer,Bytes},D},{bs_init2,Fail,D,Regs0,Flags,D}|Is]) ->
+ Regs = cg_bo_newregs(Regs0, D),
+ cg_bin_opt([{bs_init2,Fail,Bytes,Regs,Flags,D}|Is]);
+cg_bin_opt([{move,Src,D},{bs_init2,Fail,D,Regs0,Flags,D}|Is]) ->
+ Regs = cg_bo_newregs(Regs0, D),
+ cg_bin_opt([{bs_init2,Fail,Src,Regs,Flags,D}|Is]);
+cg_bin_opt([{move,Src,Dst},{bs_bits_to_bytes,Fail,Dst,Dst}|Is]) ->
+ cg_bin_opt([{bs_bits_to_bytes,Fail,Src,Dst}|Is]);
+cg_bin_opt([{move,Src1,Dst},{bs_add,Fail,[Dst,Src2,U],Dst}|Is]) ->
+ cg_bin_opt([{bs_add,Fail,[Src1,Src2,U],Dst}|Is]);
+cg_bin_opt([{bs_bits_to_bytes,Fail,{integer,N},_}|Is0]) when N rem 8 =/= 0 ->
+ case Fail of
+ {f,0} ->
+ Is = [{move,{atom,badarg},{x,0}},
+ {call_ext_only,1,{extfunc,erlang,error,1}}|Is0],
+ cg_bin_opt(Is);
+ _ ->
+ cg_bin_opt([{jump,Fail}|Is0])
+ end;
+cg_bin_opt([I|Is]) ->
+ [I|cg_bin_opt(Is)];
+cg_bin_opt([]) -> [].
+
+cg_bo_newregs(R, {x,X}) when R-1 =:= X -> R-1;
+cg_bo_newregs(R, _) -> R.
+
+%% Common for new and old binary code generation.
+
+cg_bin_put({bin_seg,S0,U,T,Fs,[E0,Next]}, Fail, Bef) ->
+ S1 = case S0 of
+ {var,Sv} -> fetch_var(Sv, Bef);
+ _ -> S0
+ end,
+ E1 = case E0 of
+ {var,V} -> fetch_var(V, Bef);
+ Other -> Other
+ end,
+ Op = case T of
+ integer -> bs_put_integer;
+ binary -> bs_put_binary;
+ float -> bs_put_float
+ end,
+ [{Op,Fail,S1,U,{field_flags,Fs},E1}|cg_bin_put(Next, Fail, Bef)];
+cg_bin_put(bin_end, _, _) -> [].
+
+%% Old style.
+
+cg_binary_old(PutCode) ->
+ [cg_bs_init(PutCode)] ++ need_bin_buf(PutCode).
+
+cg_bs_init(Code) ->
+ {Size,Fs} = foldl(fun ({_,_,{integer,N},U,_,_}, {S,Fs}) ->
+ {S + N*U,Fs};
+ (_, {S,_}) ->
+ {S,[]}
+ end, {0,[exact]}, Code),
+ {bs_init,(Size+7) div 8,{field_flags,Fs}}.
+
+need_bin_buf(Code0) ->
+ {Code1,F,H} = foldr(fun ({_,_,{integer,N},U,_,_}=Bs, {Code,F,H}) ->
+ {[Bs|Code],F,H + N*U};
+ ({_,_,_,_,_,_}=Bs, {Code,F,H}) ->
+ {[Bs|need_bin_buf_need(H, F, Code)],true,0}
+ end, {[],false,0}, Code0),
+ need_bin_buf_need(H, F, Code1).
+
+need_bin_buf_need(0, false, Rest) -> Rest;
+need_bin_buf_need(H, _, Rest) -> [{bs_need_buf,H}|Rest].
+
+cg_build_args(As, Bef) ->
+ map(fun ({var,V}) -> {put,fetch_var(V, Bef)};
+ (Other) -> {put,Other}
+ end, 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),
+ {comment({return,Rs}) ++ 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),
+ {comment({break,Bs}) ++ Ms ++ [{jump,{f,St#cg.break}}],
+ Int#sr{reg=clear_regs(Int#sr.reg)},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({var,V}, Bef) -> fetch_var(V, Bef);
+cg_reg_arg(Literal, _) -> 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 ++ [{'%live',length(As)}],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], [{var,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([], [{var,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([{var,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([A|As], Sr, I, Acc) ->
+ 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 keysearch(Src, 3, Path) of
+ {value,_} -> %We have a cycle.
+ {break_up_cycle(M, Path, ScrReg),reverse(Others, Ms0)};
+ false ->
+ collect_chain(reverse(Others, Ms0), [M|Path], [], ScrReg)
+ 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, Until, Vdb) ->
+ Sr#sr{reg=clear_dead_reg(Sr, Until, Vdb),
+ stk=clear_dead_stk(Sr#sr.stk, Until, Vdb)}.
+
+clear_dead_reg(Sr, Until, Vdb) ->
+ Reg = map(fun ({I,V}) ->
+ case vdb_find(V, Vdb) of
+ {V,_,L} when L > Until -> {I,V};
+ _ -> free %Remove anything else
+ end;
+ ({reserved,I,V}) -> {reserved,I,V};
+ (free) -> free
+ end, Sr#sr.reg),
+ reserve(Sr#sr.res, Reg, Sr#sr.stk).
+
+clear_dead_stk(Stk, Until, Vdb) ->
+ map(fun ({V}) ->
+ case vdb_find(V, Vdb) of
+ {V,_,L} when L > Until -> {V};
+ _ -> dead %Remove anything else
+ end;
+ (free) -> free;
+ (dead) -> dead
+ end, 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=[]};
+sr_merge(S1, void) -> S1#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|T1], []) -> [dead|T1];
+longest([], [dead|T2]) -> [dead|T2];
+longest([free|T1], []) -> [free|T1];
+longest([], [free|T2]) -> [free|T2];
+longest([], []) -> [].
+
+%% 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 = [ {V,F,L} || {V,F,L} <- Vdb,
+ F < Fb,
+ L >= Lf,
+ not on_stack(V, Stk0) ],
+ %% 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}.
+
+%% 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) ->
+ Res = map(fun (V) ->
+ {move,fetch_reg(V, Reg),fetch_stack(V, Stk)}
+ end, Ss),
+ Res.
+
+%% comment(C) -> ['%'{C}].
+
+%comment(C) -> [{'%',C}].
+comment(_) -> [].
+
+%% 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.
+
+% find_var(V, Sr) ->
+% case find_reg(V, Sr#sr.reg) of
+% {ok,R} -> {ok,R};
+% error ->
+% case find_stack(V, Sr#sr.stk) of
+% {ok,S} -> {ok,S};
+% error -> error
+% end
+% end.
+
+load_vars(Vs, Regs) ->
+ foldl(fun ({var,V}, Rs) -> put_reg(V, Rs) end, Regs, Vs).
+
+%% put_reg(Val, Regs) -> Regs.
+%% load_reg(Val, Reg, Regs) -> Regs.
+%% free_reg(Val, Regs) -> Regs.
+%% find_reg(Val, Regs) -> ok{r{R}} | error.
+%% fetch_reg(Val, Regs) -> r{R}.
+%% Functions to interface the registers.
+%% put_reg puts a value into a free register,
+%% load_reg loads a value into a fixed register
+%% free_reg frees a register containing a specific value.
+
+% 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}].
+
+load_reg(V, R, Rs) -> load_reg_1(V, R, Rs, 0).
+
+load_reg_1(V, I, [_|Rs], I) -> [{I,V}|Rs];
+load_reg_1(V, I, [R|Rs], C) -> [R|load_reg_1(V, I, Rs, C+1)];
+load_reg_1(V, I, [], I) -> [{I,V}];
+load_reg_1(V, I, [], C) -> [free|load_reg_1(V, I, [], C+1)].
+
+% free_reg(V, [{I,V}|Rs]) -> [free|Rs];
+% free_reg(V, [R|Rs]) -> [R|free_reg(V, Rs)];
+% free_reg(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}.
+
+%%copy_reg(Val, R, Regs) -> load_reg(Val, R, Regs).
+%%move_reg(Val, R, Regs) -> load_reg(Val, R, free_reg(Val, Regs)).
+
+%%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) ->
+ case catch put_stack_carefully1(Val, Stk0) of
+ error -> error;
+ Stk1 when list(Stk1) -> Stk1
+ 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}|Stk], I) -> {ok,{yy,I}};
+% find_stack(V, [O|Stk], I) -> find_stack(V, Stk, I+1);
+% find_stack(V, [], I) -> 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)].
+
+%%%
+%%% Finish the code generation for the bit syntax matching.
+%%%
+
+bs_function({function,Name,Arity,CLabel,Asm0}=Func) ->
+ case bs_needed(Asm0, 0, false, []) of
+ {false,[]} -> Func;
+ {true,Dict} ->
+ Asm = bs_replace(Asm0, Dict, []),
+ {function,Name,Arity,CLabel,Asm}
+ end.
+
+%%%
+%%% Pass 1: Found out which bs_restore's that are needed. For now we assume
+%%% that a bs_restore is needed unless it is directly preceeded by a bs_save.
+%%%
+
+bs_needed([{bs_save,Name},{bs_restore,Name}|T], N, _BsUsed, Dict) ->
+ bs_needed(T, N, true, Dict);
+bs_needed([{bs_save,_Name}|T], N, _BsUsed, Dict) ->
+ bs_needed(T, N, true, Dict);
+bs_needed([{bs_restore,Name}|T], N, _BsUsed, Dict) ->
+ case keysearch(Name, 1, Dict) of
+ {value,{Name,_}} -> bs_needed(T, N, true, Dict);
+ false -> bs_needed(T, N+1, true, [{Name,N}|Dict])
+ end;
+bs_needed([{bs_init,_,_}|T], N, _, Dict) ->
+ bs_needed(T, N, true, Dict);
+bs_needed([{bs_init2,_,_,_,_,_}|T], N, _, Dict) ->
+ bs_needed(T, N, true, Dict);
+bs_needed([{bs_start_match,_,_}|T], N, _, Dict) ->
+ bs_needed(T, N, true, Dict);
+bs_needed([_|T], N, BsUsed, Dict) ->
+ bs_needed(T, N, BsUsed, Dict);
+bs_needed([], _, BsUsed, Dict) -> {BsUsed,Dict}.
+
+%%%
+%%% Pass 2: Only needed if there were some bs_* instructions found.
+%%%
+%%% Remove any bs_save with a name that never were found to be restored
+%%% in the first pass.
+%%%
+
+bs_replace([{bs_save,Name}=Save,{bs_restore,Name}|T], Dict, Acc) ->
+ bs_replace([Save|T], Dict, Acc);
+bs_replace([{bs_save,Name}|T], Dict, Acc) ->
+ case keysearch(Name, 1, Dict) of
+ {value,{Name,N}} ->
+ bs_replace(T, Dict, [{bs_save,N}|Acc]);
+ false ->
+ bs_replace(T, Dict, Acc)
+ end;
+bs_replace([{bs_restore,Name}|T], Dict, Acc) ->
+ case keysearch(Name, 1, Dict) of
+ {value,{Name,N}} ->
+ bs_replace(T, Dict, [{bs_restore,N}|Acc]);
+ false ->
+ bs_replace(T, Dict, Acc)
+ end;
+bs_replace([{bs_init2,Fail,Bytes,Regs,Flags,Dst}|T0], Dict, Acc) ->
+ case bs_find_test_heap(T0) of
+ none ->
+ bs_replace(T0, Dict, [{bs_init2,Fail,Bytes,0,Regs,Flags,Dst}|Acc]);
+ {T,Words} ->
+ bs_replace(T, Dict, [{bs_init2,Fail,Bytes,Words,Regs,Flags,Dst}|Acc])
+ end;
+bs_replace([H|T], Dict, Acc) ->
+ bs_replace(T, Dict, [H|Acc]);
+bs_replace([], _, Acc) -> reverse(Acc).
+
+bs_find_test_heap(Is) ->
+ bs_find_test_heap_1(Is, []).
+
+bs_find_test_heap_1([{bs_put_integer,_,_,_,_,_}=I|Is], Acc) ->
+ bs_find_test_heap_1(Is, [I|Acc]);
+bs_find_test_heap_1([{bs_put_float,_,_,_,_,_}=I|Is], Acc) ->
+ bs_find_test_heap_1(Is, [I|Acc]);
+bs_find_test_heap_1([{bs_put_binary,_,_,_,_,_}=I|Is], Acc) ->
+ bs_find_test_heap_1(Is, [I|Acc]);
+bs_find_test_heap_1([{test_heap,Words,_}|Is], Acc) ->
+ {reverse(Acc, Is),Words};
+bs_find_test_heap_1(_, _) -> none.
+
+%% new_label(St) -> {L,St}.
+
+new_label(St) ->
+ L = St#cg.lcount,
+ {L,St#cg{lcount=L+1}}.
+
+flatmapfoldl(F, Accu0, [Hd|Tail]) ->
+ {R,Accu1} = F(Hd, Accu0),
+ {Rs,Accu2} = flatmapfoldl(F, Accu1, Tail),
+ {R++Rs,Accu2};
+flatmapfoldl(_, Accu, []) -> {[],Accu}.
+
+flatmapfoldr(F, Accu0, [Hd|Tail]) ->
+ {Rs,Accu1} = flatmapfoldr(F, Accu0, Tail),
+ {R,Accu2} = F(Hd, Accu1),
+ {R++Rs,Accu2};
+flatmapfoldr(_, Accu, []) -> {[],Accu}.