%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 1998-2014. All Rights Reserved.
%%
%% 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 online 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.
%%
%% %CopyrightEnd%
%%
%% Purpose: Maintain atom, import, export, and other tables for assembler.
-module(beam_dict).
-export([new/0,opcode/2,highest_opcode/1,
atom/2,local/4,export/4,import/4,
string/2,lambda/3,literal/2,line/2,fname/2,
atom_table/1,local_table/1,export_table/1,import_table/1,
string_table/1,lambda_table/1,literal_table/1,
line_table/1]).
-type label() :: non_neg_integer().
-type index() :: non_neg_integer().
-type atom_tab() :: #{atom() => index()}.
-type import_tab() :: gb_trees:tree(mfa(), index()).
-type fname_tab() :: #{Name :: term() => index()}.
-type line_tab() :: #{{Fname :: index(), Line :: term()} => index()}.
-type literal_tab() :: dict:dict(Literal :: term(), index()).
-record(asm,
{atoms = #{} :: atom_tab(),
exports = [] :: [{label(), arity(), label()}],
locals = [] :: [{label(), arity(), label()}],
imports = gb_trees:empty() :: import_tab(),
strings = <<>> :: binary(), %String pool
lambdas = [], %[{...}]
literals = dict:new() :: literal_tab(),
fnames = #{} :: fname_tab(),
lines = #{} :: line_tab(),
num_lines = 0 :: non_neg_integer(), %Number of line instructions
next_import = 0 :: non_neg_integer(),
string_offset = 0 :: non_neg_integer(),
next_literal = 0 :: non_neg_integer(),
highest_opcode = 0 :: non_neg_integer()
}).
-type bdict() :: #asm{}.
%%-----------------------------------------------------------------------------
-spec new() -> bdict().
new() ->
#asm{}.
%% Remember the highest opcode.
-spec opcode(non_neg_integer(), bdict()) -> bdict().
opcode(Op, Dict) when Dict#asm.highest_opcode >= Op -> Dict;
opcode(Op, Dict) -> Dict#asm{highest_opcode=Op}.
%% Returns the highest opcode encountered.
-spec highest_opcode(bdict()) -> non_neg_integer().
highest_opcode(#asm{highest_opcode=Op}) -> Op.
%% Returns the index for an atom (adding it to the atom table if necessary).
%% atom(Atom, Dict) -> {Index,Dict'}
-spec atom(atom(), bdict()) -> {pos_integer(), bdict()}.
atom(Atom, #asm{atoms=Atoms}=Dict) when is_atom(Atom) ->
case Atoms of
#{ Atom := Index} -> {Index,Dict};
_ ->
NextIndex = maps:size(Atoms) + 1,
{NextIndex,Dict#asm{atoms=Atoms#{Atom=>NextIndex}}}
end.
%% Remembers an exported function.
%% export(Func, Arity, Label, Dict) -> Dict'
-spec export(atom(), arity(), label(), bdict()) -> bdict().
export(Func, Arity, Label, Dict0) when is_atom(Func),
is_integer(Arity),
is_integer(Label) ->
{Index, Dict1} = atom(Func, Dict0),
Dict1#asm{exports = [{Index, Arity, Label}| Dict1#asm.exports]}.
%% Remembers a local function.
%% local(Func, Arity, Label, Dict) -> Dict'
-spec local(atom(), arity(), label(), bdict()) -> bdict().
local(Func, Arity, Label, Dict0) when is_atom(Func),
is_integer(Arity),
is_integer(Label) ->
{Index,Dict1} = atom(Func, Dict0),
Dict1#asm{locals=[{Index,Arity,Label}|Dict1#asm.locals]}.
%% Returns the index for an import entry (adding it to the import table if necessary).
%% import(Mod, Func, Arity, Dict) -> {Index,Dict'}
-spec import(atom(), atom(), arity(), bdict()) -> {non_neg_integer(), bdict()}.
import(Mod0, Name0, Arity, #asm{imports=Imp0,next_import=NextIndex}=D0)
when is_atom(Mod0), is_atom(Name0), is_integer(Arity) ->
{Mod,D1} = atom(Mod0, D0),
{Name,D2} = atom(Name0, D1),
MFA = {Mod,Name,Arity},
case gb_trees:lookup(MFA, Imp0) of
{value,Index} ->
{Index,D2};
none ->
Imp = gb_trees:insert(MFA, NextIndex, Imp0),
{NextIndex,D2#asm{imports=Imp,next_import=NextIndex+1}}
end.
%% Returns the index for a string in the string table (adding the string to the
%% table if necessary).
%% string(String, Dict) -> {Offset, Dict'}
-spec string(string(), bdict()) -> {non_neg_integer(), bdict()}.
string(Str, Dict) when is_list(Str) ->
#asm{strings=Strings,string_offset=NextOffset} = Dict,
StrBin = list_to_binary(Str),
case old_string(StrBin, Strings) of
none ->
NewDict = Dict#asm{strings = <<Strings/binary,StrBin/binary>>,
string_offset=NextOffset+byte_size(StrBin)},
{NextOffset,NewDict};
Offset when is_integer(Offset) ->
{NextOffset-Offset,Dict}
end.
%% Returns the index for a fun entry.
%% lambda(Lbl, NumFree, Dict) -> {Index,Dict'}
-spec lambda(label(), non_neg_integer(), bdict()) ->
{non_neg_integer(), bdict()}.
lambda(Lbl, NumFree, #asm{lambdas=Lambdas0}=Dict) ->
OldIndex = length(Lambdas0),
%% Set Index the same as OldIndex.
Index = OldIndex,
%% Initialize OldUniq to 0. It will be set to an unique value
%% based on the MD5 checksum of the BEAM code for the module.
OldUniq = 0,
Lambdas = [{Lbl,{OldIndex,Lbl,Index,NumFree,OldUniq}}|Lambdas0],
{OldIndex,Dict#asm{lambdas=Lambdas}}.
%% Returns the index for a literal (adding it to the literal table if necessary).
%% literal(Literal, Dict) -> {Index,Dict'}
-spec literal(term(), bdict()) -> {non_neg_integer(), bdict()}.
literal(Lit, #asm{literals=Tab0,next_literal=NextIndex}=Dict) ->
case dict:find(Lit, Tab0) of
{ok,Index} ->
{Index,Dict};
error ->
Tab = dict:store(Lit, NextIndex, Tab0),
{NextIndex,Dict#asm{literals=Tab,next_literal=NextIndex+1}}
end.
%% Returns the index for a line instruction (adding information
%% to the location information table).
-spec line(list(), bdict()) -> {non_neg_integer(), bdict()}.
line([], #asm{num_lines=N}=Dict) ->
%% No location available. Return the special pre-defined
%% index 0.
{0,Dict#asm{num_lines=N+1}};
line([{location,Name,Line}], #asm{lines=Lines,num_lines=N}=Dict0) ->
{FnameIndex,Dict1} = fname(Name, Dict0),
Key = {FnameIndex,Line},
case Lines of
#{Key := Index} -> {Index,Dict1#asm{num_lines=N+1}};
_ ->
Index = maps:size(Lines) + 1,
{Index, Dict1#asm{lines=Lines#{Key=>Index},num_lines=N+1}}
end.
fname(Name, #asm{fnames=Fnames}=Dict) ->
case Fnames of
#{Name := Index} -> {Index,Dict};
_ ->
Index = maps:size(Fnames),
{Index,Dict#asm{fnames=Fnames#{Name=>Index}}}
end.
%% Returns the atom table.
%% atom_table(Dict) -> {LastIndex,[Length,AtomString...]}
-spec atom_table(bdict()) -> {non_neg_integer(), [[non_neg_integer(),...]]}.
atom_table(#asm{atoms=Atoms}) ->
NumAtoms = maps:size(Atoms),
Sorted = lists:keysort(2, maps:to_list(Atoms)),
{NumAtoms,[begin
L = atom_to_list(A),
[length(L)|L]
end || {A,_} <- Sorted]}.
%% Returns the table of local functions.
%% local_table(Dict) -> {NumLocals, [{Function, Arity, Label}...]}
-spec local_table(bdict()) -> {non_neg_integer(), [{label(),arity(),label()}]}.
local_table(#asm{locals = Locals}) ->
{length(Locals),Locals}.
%% Returns the export table.
%% export_table(Dict) -> {NumExports, [{Function, Arity, Label}...]}
-spec export_table(bdict()) -> {non_neg_integer(), [{label(),arity(),label()}]}.
export_table(#asm{exports = Exports}) ->
{length(Exports),Exports}.
%% Returns the import table.
%% import_table(Dict) -> {NumImports, [{Module, Function, Arity}...]}
-spec import_table(bdict()) -> {non_neg_integer(), [{label(),label(),arity()}]}.
import_table(#asm{imports=Imp,next_import=NumImports}) ->
Sorted = lists:keysort(2, gb_trees:to_list(Imp)),
ImpTab = [MFA || {MFA,_} <- Sorted],
{NumImports,ImpTab}.
-spec string_table(bdict()) -> {non_neg_integer(), binary()}.
string_table(#asm{strings=Strings,string_offset=Size}) ->
{Size,Strings}.
-spec lambda_table(bdict()) -> {non_neg_integer(), [<<_:192>>]}.
lambda_table(#asm{locals=Loc0,lambdas=Lambdas0}) ->
Lambdas1 = sofs:relation(Lambdas0),
Loc = sofs:relation([{Lbl,{F,A}} || {F,A,Lbl} <- Loc0]),
Lambdas2 = sofs:relative_product1(Lambdas1, Loc),
Lambdas = [<<F:32,A:32,Lbl:32,Index:32,NumFree:32,OldUniq:32>> ||
{{_,Lbl,Index,NumFree,OldUniq},{F,A}} <- sofs:to_external(Lambdas2)],
{length(Lambdas),Lambdas}.
%% Returns the literal table.
%% literal_table(Dict) -> {NumLiterals, [<<TermSize>>,TermInExternalFormat]}
-spec literal_table(bdict()) -> {non_neg_integer(), [[binary(),...]]}.
literal_table(#asm{literals=Tab,next_literal=NumLiterals}) ->
L0 = dict:fold(fun(Lit, Num, Acc) ->
[{Num,my_term_to_binary(Lit)}|Acc]
end, [], Tab),
L1 = lists:sort(L0),
L = [[<<(byte_size(Term)):32>>,Term] || {_,Term} <- L1],
{NumLiterals,L}.
my_term_to_binary(Term) ->
term_to_binary(Term, [{minor_version,1}]).
%% Return the line table.
-spec line_table(bdict()) ->
{non_neg_integer(), %Number of line instructions.
non_neg_integer(),[string()],
non_neg_integer(),[{non_neg_integer(),non_neg_integer()}]}.
line_table(#asm{fnames=Fnames0,lines=Lines0,num_lines=NumLineInstrs}) ->
NumFnames = maps:size(Fnames0),
Fnames1 = lists:keysort(2, maps:to_list(Fnames0)),
Fnames = [Name || {Name,_} <- Fnames1],
NumLines = maps:size(Lines0),
Lines1 = lists:keysort(2, maps:to_list(Lines0)),
Lines = [L || {L,_} <- Lines1],
{NumLineInstrs,NumFnames,Fnames,NumLines,Lines}.
%% Search for binary string Str in the binary string pool Pool.
%% old_string(Str, Pool) -> none | Index
-spec old_string(binary(), binary()) -> 'none' | pos_integer().
old_string(Str, Pool) ->
case binary:match(Pool, Str) of
nomatch -> none;
{Start,_Length} -> byte_size(Pool) - Start
end.
