%% -*- erlang-indent-level: 2 -*-
%%-----------------------------------------------------------------------
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 2006-2012. 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%
%%
%%%-------------------------------------------------------------------
%%% File : dialyzer_callgraph.erl
%%% Author : Tobias Lindahl <[email protected]>
%%% Description :
%%%
%%% Created : 30 Mar 2005 by Tobias Lindahl <[email protected]>
%%%-------------------------------------------------------------------
-module(dialyzer_callgraph).
-export([add_edges/2,
all_nodes/1,
delete/1,
finalize/1,
is_escaping/2,
is_self_rec/2,
non_local_calls/1,
lookup_rec_var/2,
lookup_call_site/2,
lookup_label/2,
lookup_name/2,
modules/1,
module_deps/1,
%% module_postorder/1,
module_postorder_from_funs/2,
new/0,
in_neighbours/2,
renew_race_info/4,
reset_from_funs/2,
scan_core_tree/2,
strip_module_deps/2,
take_scc/1,
remove_external/1,
to_dot/2,
to_ps/3]).
-export([cleanup/1, get_digraph/1, get_named_tables/1, get_public_tables/1,
get_race_code/1, get_race_detection/1, race_code_new/1,
put_digraph/2, put_race_code/2, put_race_detection/2,
put_named_tables/2, put_public_tables/2, put_behaviour_api_calls/2,
get_behaviour_api_calls/1]).
-export_type([callgraph/0, mfa_or_funlbl/0]).
-include("dialyzer.hrl").
%%----------------------------------------------------------------------
-type mfa_or_funlbl() :: label() | mfa().
-type scc() :: [mfa_or_funlbl()].
-type mfa_calls() :: [{mfa_or_funlbl(), mfa_or_funlbl()}].
%%-----------------------------------------------------------------------------
%% A callgraph is a directed graph where the nodes are functions and a
%% call between two functions is an edge from the caller to the callee.
%%
%% calls - A mapping from call site (and apply site) labels
%% to the possible functions that can be called.
%% digraph - A digraph representing the callgraph.
%% Nodes are represented as MFAs or labels.
%% esc - A set of all escaping functions as reported by dialyzer_dep.
%% postorder - A list of strongly connected components of the callgraph
%% sorted in a topological bottom-up order.
%% This is produced by calling finalize/1.
%% name_map - A mapping from label to MFA.
%% rev_name_map - A reverse mapping of the name_map.
%% rec_var_map - A dict mapping from letrec bound labels to function names.
%% Only for top level functions (from module defs).
%% self_rec - A set containing all self recursive functions.
%% Note that this contains MFAs for named functions and labels
%% whenever applicable.
%%-----------------------------------------------------------------------------
-record(callgraph, {digraph = digraph:new() :: digraph(),
esc = sets:new() :: set(),
name_map = dict:new() :: dict(),
rev_name_map = dict:new() :: dict(),
postorder = [] :: [scc()],
rec_var_map = dict:new() :: dict(),
self_rec = sets:new() :: set(),
calls = dict:new() :: dict(),
race_code = dict:new() :: dict(),
public_tables = [] :: [label()],
named_tables = [] :: [string()],
race_detection = false :: boolean(),
beh_api_calls = [] :: [{mfa(), mfa()}]}).
%% Exported Types
-type callgraph() :: #callgraph{}.
%%----------------------------------------------------------------------
-spec new() -> callgraph().
new() ->
#callgraph{}.
-spec delete(callgraph()) -> 'true'.
delete(#callgraph{digraph = Digraph}) ->
digraph_delete(Digraph).
-spec all_nodes(callgraph()) -> [mfa()].
all_nodes(#callgraph{digraph = DG}) ->
digraph_vertices(DG).
-spec lookup_rec_var(label(), callgraph()) -> 'error' | {'ok', mfa()}.
lookup_rec_var(Label, #callgraph{rec_var_map = RecVarMap})
when is_integer(Label) ->
dict:find(Label, RecVarMap).
-spec lookup_call_site(label(), callgraph()) -> 'error' | {'ok', [_]}. % XXX: refine
lookup_call_site(Label, #callgraph{calls = Calls})
when is_integer(Label) ->
dict:find(Label, Calls).
-spec lookup_name(label(), callgraph()) -> 'error' | {'ok', mfa()}.
lookup_name(Label, #callgraph{name_map = NameMap})
when is_integer(Label) ->
dict:find(Label, NameMap).
-spec lookup_label(mfa_or_funlbl(), callgraph()) -> 'error' | {'ok', integer()}.
lookup_label({_,_,_} = MFA, #callgraph{rev_name_map = RevNameMap}) ->
dict:find(MFA, RevNameMap);
lookup_label(Label, #callgraph{}) when is_integer(Label) ->
{ok, Label}.
-spec in_neighbours(mfa_or_funlbl(), callgraph()) -> 'none' | [mfa_or_funlbl(),...].
in_neighbours(Label, #callgraph{digraph = Digraph, name_map = NameMap})
when is_integer(Label) ->
Name = case dict:find(Label, NameMap) of
{ok, Val} -> Val;
error -> Label
end,
digraph_in_neighbours(Name, Digraph);
in_neighbours({_, _, _} = MFA, #callgraph{digraph = Digraph}) ->
digraph_in_neighbours(MFA, Digraph).
-spec is_self_rec(mfa_or_funlbl(), callgraph()) -> boolean().
is_self_rec(MfaOrLabel, #callgraph{self_rec = SelfRecs}) ->
sets:is_element(MfaOrLabel, SelfRecs).
-spec is_escaping(label(), callgraph()) -> boolean().
is_escaping(Label, #callgraph{esc = Esc}) when is_integer(Label) ->
sets:is_element(Label, Esc).
-type callgraph_edge() :: {mfa_or_funlbl(),mfa_or_funlbl()}.
-spec add_edges([callgraph_edge()], callgraph()) -> callgraph().
add_edges([], CG) ->
CG;
add_edges(Edges, #callgraph{digraph = Digraph} = CG) ->
CG#callgraph{digraph = digraph_add_edges(Edges, Digraph)}.
-spec add_edges([callgraph_edge()], [mfa_or_funlbl()], callgraph()) -> callgraph().
add_edges(Edges, MFAs, #callgraph{digraph = DG} = CG) ->
DG = digraph_confirm_vertices(MFAs, DG),
add_edges(Edges, CG).
-spec take_scc(callgraph()) -> 'none' | {'ok', scc(), callgraph()}.
take_scc(#callgraph{postorder = [SCC|SCCs]} = CG) ->
{ok, SCC, CG#callgraph{postorder = SCCs}};
take_scc(#callgraph{postorder = []}) ->
none.
-spec remove_external(callgraph()) -> {callgraph(), [tuple()]}.
remove_external(#callgraph{digraph = DG} = CG) ->
{DG, External} = digraph_remove_external(DG),
{CG, External}.
-spec non_local_calls(callgraph()) -> mfa_calls().
non_local_calls(#callgraph{digraph = DG}) ->
Edges = digraph_edges(DG),
find_non_local_calls(Edges, sets:new()).
-spec find_non_local_calls([{mfa_or_funlbl(), mfa_or_funlbl()}], set()) -> mfa_calls().
find_non_local_calls([{{M,_,_}, {M,_,_}}|Left], Set) ->
find_non_local_calls(Left, Set);
find_non_local_calls([{{M1,_,_}, {M2,_,_}} = Edge|Left], Set) when M1 =/= M2 ->
find_non_local_calls(Left, sets:add_element(Edge, Set));
find_non_local_calls([{{_,_,_}, Label}|Left], Set) when is_integer(Label) ->
find_non_local_calls(Left, Set);
find_non_local_calls([{Label, {_,_,_}}|Left], Set) when is_integer(Label) ->
find_non_local_calls(Left, Set);
find_non_local_calls([{Label1, Label2}|Left], Set) when is_integer(Label1),
is_integer(Label2) ->
find_non_local_calls(Left, Set);
find_non_local_calls([], Set) ->
sets:to_list(Set).
-spec renew_race_info(callgraph(), dict(), [label()], [string()]) ->
callgraph().
renew_race_info(CG, RaceCode, PublicTables, NamedTables) ->
CG#callgraph{race_code = RaceCode,
public_tables = PublicTables,
named_tables = NamedTables}.
%%----------------------------------------------------------------------
%% Handling of modules & SCCs
%%----------------------------------------------------------------------
-spec modules(callgraph()) -> [module()].
modules(#callgraph{digraph = DG}) ->
ordsets:from_list([M || {M,_F,_A} <- digraph_vertices(DG)]).
-spec module_postorder(callgraph()) -> [module()].
module_postorder(#callgraph{digraph = DG}) ->
Edges = digraph_edges(DG),
Nodes = ordsets:from_list([M || {M,_F,_A} <- digraph_vertices(DG)]),
MDG = digraph:new([acyclic]),
MDG1 = digraph_confirm_vertices(Nodes, MDG),
MDG2 = create_module_digraph(Edges, MDG1),
PostOrder = digraph_utils:postorder(MDG2),
digraph:delete(MDG2),
PostOrder.
%% The module deps of a module are modules that depend on the module
-spec module_deps(callgraph()) -> dict().
module_deps(#callgraph{digraph = DG}) ->
Edges = digraph_edges(DG),
Nodes = ordsets:from_list([M || {M,_F,_A} <- digraph_vertices(DG)]),
MDG = digraph:new(),
MDG1 = digraph_confirm_vertices(Nodes, MDG),
MDG2 = create_module_digraph(Edges, MDG1),
Deps = [{N, ordsets:from_list(digraph:in_neighbours(MDG2, N))}
|| N <- Nodes],
digraph_delete(MDG2),
dict:from_list(Deps).
-spec strip_module_deps(dict(), set()) -> dict().
strip_module_deps(ModDeps, StripSet) ->
FilterFun1 = fun(Val) -> not sets:is_element(Val, StripSet) end,
MapFun = fun(_Key, ValSet) -> ordsets:filter(FilterFun1, ValSet) end,
ModDeps1 = dict:map(MapFun, ModDeps),
FilterFun2 = fun(_Key, ValSet) -> ValSet =/= [] end,
dict:filter(FilterFun2, ModDeps1).
create_module_digraph([{{M, _, _}, {M, _, _}}|Left], MDG) ->
create_module_digraph(Left, MDG);
create_module_digraph([{{M1, _, _}, {M2, _, _}}|Left], MDG) ->
create_module_digraph(Left, digraph_add_edge(M1, M2, MDG));
create_module_digraph([{_, _}|Left], MDG) ->
create_module_digraph(Left, MDG);
create_module_digraph([], MDG) ->
MDG.
-spec finalize(callgraph()) -> callgraph().
finalize(#callgraph{digraph = DG} = CG) ->
CG#callgraph{postorder = digraph_finalize(DG)}.
-spec reset_from_funs([mfa_or_funlbl()], callgraph()) -> callgraph().
reset_from_funs(Funs, #callgraph{digraph = DG} = CG) ->
SubGraph = digraph_reaching_subgraph(Funs, DG),
Postorder = digraph_finalize(SubGraph),
digraph_delete(SubGraph),
CG#callgraph{postorder = Postorder}.
-spec module_postorder_from_funs([mfa_or_funlbl()], callgraph()) -> [module()].
module_postorder_from_funs(Funs, #callgraph{digraph = DG} = CG) ->
SubGraph = digraph_reaching_subgraph(Funs, DG),
PO = module_postorder(CG#callgraph{digraph = SubGraph}),
digraph_delete(SubGraph),
PO.
%%----------------------------------------------------------------------
%% Core code
%%----------------------------------------------------------------------
%% The core tree must be labeled as by cerl_trees:label/1 (or /2).
%% The set of labels in the tree must be disjoint from the set of
%% labels already occuring in the callgraph.
-spec scan_core_tree(cerl:c_module(), callgraph()) -> callgraph().
scan_core_tree(Tree, #callgraph{calls = OldCalls,
esc = OldEsc,
name_map = OldNameMap,
rec_var_map = OldRecVarMap,
rev_name_map = OldRevNameMap,
self_rec = OldSelfRec} = CG) ->
%% Build name map and recursion variable maps.
{NewNameMap, NewRevNameMap, NewRecVarMap} =
build_maps(Tree, OldRecVarMap, OldNameMap, OldRevNameMap),
%% First find the module-local dependencies.
{Deps0, EscapingFuns, Calls} = dialyzer_dep:analyze(Tree),
NewCalls = dict:merge(fun(_Key, Val, Val) -> Val end, OldCalls, Calls),
NewEsc = sets:union(sets:from_list(EscapingFuns), OldEsc),
LabelEdges = get_edges_from_deps(Deps0),
%% Find the self recursive functions. Named functions get both the
%% key and their name for convenience.
SelfRecs0 = lists:foldl(fun({Key, Key}, Acc) ->
case dict:find(Key, NewNameMap) of
error -> [Key|Acc];
{ok, Name} -> [Key, Name|Acc]
end;
(_, Acc) -> Acc
end, [], LabelEdges),
SelfRecs = sets:union(sets:from_list(SelfRecs0), OldSelfRec),
NamedEdges1 = name_edges(LabelEdges, NewNameMap),
%% We need to scan for inter-module calls since these are not tracked
%% by dialyzer_dep. Note that the caller is always recorded as the
%% top level function. This is OK since the included functions are
%% stored as scc with the parent.
NamedEdges2 = scan_core_funs(Tree),
%% Confirm all nodes in the tree.
Names1 = lists:append([[X, Y] || {X, Y} <- NamedEdges1]),
Names2 = ordsets:from_list(Names1),
%% Get rid of the 'top' function from nodes and edges.
Names3 = ordsets:del_element(top, Names2),
NewNamedEdges2 =
[E || {From, To} = E <- NamedEdges2, From =/= top, To =/= top],
NewNamedEdges1 =
[E || {From, To} = E <- NamedEdges1, From =/= top, To =/= top],
NamedEdges3 = NewNamedEdges1 ++ NewNamedEdges2,
CG1 = add_edges(NamedEdges3, Names3, CG),
CG1#callgraph{calls = NewCalls,
esc = NewEsc,
name_map = NewNameMap,
rec_var_map = NewRecVarMap,
rev_name_map = NewRevNameMap,
self_rec = SelfRecs}.
build_maps(Tree, RecVarMap, NameMap, RevNameMap) ->
%% We only care about the named (top level) functions. The anonymous
%% functions will be analysed together with their parents.
Defs = cerl:module_defs(Tree),
Mod = cerl:atom_val(cerl:module_name(Tree)),
lists:foldl(fun({Var, Function}, {AccNameMap, AccRevNameMap, AccRecVarMap}) ->
FunName = cerl:fname_id(Var),
Arity = cerl:fname_arity(Var),
MFA = {Mod, FunName, Arity},
{dict:store(get_label(Function), MFA, AccNameMap),
dict:store(MFA, get_label(Function), AccRevNameMap),
dict:store(get_label(Var), MFA, AccRecVarMap)}
end, {NameMap, RevNameMap, RecVarMap}, Defs).
get_edges_from_deps(Deps) ->
%% Convert the dependencies as produced by dialyzer_dep to a list of
%% edges. Also, remove 'external' since we are not interested in
%% this information.
Edges = dict:fold(fun(external, _Set, Acc) -> Acc;
(Caller, Set, Acc) ->
[[{Caller, Callee} || Callee <- Set,
Callee =/= external]|Acc]
end, [], Deps),
lists:flatten(Edges).
name_edges(Edges, NameMap) ->
%% If a label is present in the name map it is renamed. Otherwise
%% keep the label as the identity.
MapFun = fun(X) ->
case dict:find(X, NameMap) of
error -> X;
{ok, MFA} -> MFA
end
end,
name_edges(Edges, MapFun, NameMap, []).
name_edges([{From, To}|Left], MapFun, NameMap, Acc) ->
NewFrom = MapFun(From),
NewTo = MapFun(To),
name_edges(Left, MapFun, NameMap, [{NewFrom, NewTo}|Acc]);
name_edges([], _MapFun, _NameMap, Acc) ->
Acc.
scan_core_funs(Tree) ->
Defs = cerl:module_defs(Tree),
Mod = cerl:atom_val(cerl:module_name(Tree)),
DeepEdges = lists:foldl(fun({Var, Function}, Edges) ->
FunName = cerl:fname_id(Var),
Arity = cerl:fname_arity(Var),
MFA = {Mod, FunName, Arity},
[scan_one_core_fun(Function, MFA)|Edges]
end, [], Defs),
lists:flatten(DeepEdges).
scan_one_core_fun(TopTree, FunName) ->
FoldFun = fun(Tree, Acc) ->
case cerl:type(Tree) of
call ->
CalleeM = cerl:call_module(Tree),
CalleeF = cerl:call_name(Tree),
A = length(cerl:call_args(Tree)),
case (cerl:is_c_atom(CalleeM) andalso
cerl:is_c_atom(CalleeF)) of
true ->
M = cerl:atom_val(CalleeM),
F = cerl:atom_val(CalleeF),
case erl_bif_types:is_known(M, F, A) of
true -> Acc;
false -> [{FunName, {M, F, A}}|Acc]
end;
false ->
%% We cannot handle run-time bindings
Acc
end;
_ ->
%% Nothing that can introduce new edges in the callgraph.
Acc
end
end,
cerl_trees:fold(FoldFun, [], TopTree).
get_label(T) ->
case cerl:get_ann(T) of
[{label, L} | _] when is_integer(L) -> L;
_ -> erlang:error({missing_label, T})
end.
%%----------------------------------------------------------------------
%% Digraph
%%----------------------------------------------------------------------
digraph_add_edges([{From, To}|Left], DG) ->
digraph_add_edges(Left, digraph_add_edge(From, To, DG));
digraph_add_edges([], DG) ->
DG.
digraph_add_edge(From, To, DG) ->
case digraph:vertex(DG, From) of
false -> digraph:add_vertex(DG, From);
{From, _} -> ok
end,
case digraph:vertex(DG, To) of
false -> digraph:add_vertex(DG, To);
{To, _} -> ok
end,
digraph:add_edge(DG, {From, To}, From, To, []),
DG.
digraph_confirm_vertices([MFA|Left], DG) ->
digraph:add_vertex(DG, MFA, confirmed),
digraph_confirm_vertices(Left, DG);
digraph_confirm_vertices([], DG) ->
DG.
digraph_remove_external(DG) ->
Vertices = digraph:vertices(DG),
Unconfirmed = remove_unconfirmed(Vertices, DG),
{DG, Unconfirmed}.
remove_unconfirmed(Vertexes, DG) ->
remove_unconfirmed(Vertexes, DG, []).
remove_unconfirmed([V|Left], DG, Unconfirmed) ->
case digraph:vertex(DG, V) of
{V, confirmed} -> remove_unconfirmed(Left, DG, Unconfirmed);
{V, []} -> remove_unconfirmed(Left, DG, [V|Unconfirmed])
end;
remove_unconfirmed([], DG, Unconfirmed) ->
BadCalls = lists:append([digraph:in_edges(DG, V) || V <- Unconfirmed]),
BadCallsSorted = lists:keysort(1, BadCalls),
digraph:del_vertices(DG, Unconfirmed),
BadCallsSorted.
digraph_delete(DG) ->
digraph:delete(DG).
digraph_edges(DG) ->
digraph:edges(DG).
digraph_vertices(DG) ->
digraph:vertices(DG).
digraph_in_neighbours(V, DG) ->
case digraph:in_neighbours(DG, V) of
[] -> none;
List -> List
end.
digraph_postorder(Digraph) ->
digraph_utils:postorder(Digraph).
digraph_finalize(DG) ->
DG1 = digraph_utils:condensation(DG),
Postorder = digraph_postorder(DG1),
digraph:delete(DG1),
Postorder.
digraph_reaching_subgraph(Funs, DG) ->
Vertices = digraph_utils:reaching(Funs, DG),
digraph_utils:subgraph(DG, Vertices).
%%----------------------------------------------------------------------
%% Races
%%----------------------------------------------------------------------
-spec cleanup(callgraph()) -> callgraph().
cleanup(#callgraph{digraph = Digraph,
name_map = NameMap,
rev_name_map = RevNameMap,
public_tables = PublicTables,
named_tables = NamedTables,
race_code = RaceCode}) ->
#callgraph{digraph = Digraph,
name_map = NameMap,
rev_name_map = RevNameMap,
public_tables = PublicTables,
named_tables = NamedTables,
race_code = RaceCode}.
-spec get_digraph(callgraph()) -> digraph().
get_digraph(#callgraph{digraph = Digraph}) ->
Digraph.
-spec get_named_tables(callgraph()) -> [string()].
get_named_tables(#callgraph{named_tables = NamedTables}) ->
NamedTables.
-spec get_public_tables(callgraph()) -> [label()].
get_public_tables(#callgraph{public_tables = PT}) ->
PT.
-spec get_race_code(callgraph()) -> dict().
get_race_code(#callgraph{race_code = RaceCode}) ->
RaceCode.
-spec get_race_detection(callgraph()) -> boolean().
get_race_detection(#callgraph{race_detection = RD}) ->
RD.
-spec race_code_new(callgraph()) -> callgraph().
race_code_new(Callgraph) ->
Callgraph#callgraph{race_code = dict:new()}.
-spec put_digraph(digraph(), callgraph()) -> callgraph().
put_digraph(Digraph, Callgraph) ->
Callgraph#callgraph{digraph = Digraph}.
-spec put_race_code(dict(), callgraph()) -> callgraph().
put_race_code(RaceCode, Callgraph) ->
Callgraph#callgraph{race_code = RaceCode}.
-spec put_race_detection(boolean(), callgraph()) -> callgraph().
put_race_detection(RaceDetection, Callgraph) ->
Callgraph#callgraph{race_detection = RaceDetection}.
-spec put_named_tables([string()], callgraph()) -> callgraph().
put_named_tables(NamedTables, Callgraph) ->
Callgraph#callgraph{named_tables = NamedTables}.
-spec put_public_tables([label()], callgraph()) -> callgraph().
put_public_tables(PublicTables, Callgraph) ->
Callgraph#callgraph{public_tables = PublicTables}.
%%=============================================================================
%% Utilities for 'dot'
%%=============================================================================
-spec to_dot(callgraph(), file:filename()) -> 'ok'.
to_dot(#callgraph{digraph = DG, esc = Esc} = CG, File) ->
Fun = fun(L) ->
case lookup_name(L, CG) of
error -> L;
{ok, Name} -> Name
end
end,
Escaping = [{Fun(L), {color, red}}
|| L <- sets:to_list(Esc), L =/= external],
Vertices = digraph_edges(DG),
hipe_dot:translate_list(Vertices, File, "CG", Escaping).
-spec to_ps(callgraph(), file:filename(), string()) -> 'ok'.
to_ps(#callgraph{} = CG, File, Args) ->
Dot_File = filename:rootname(File) ++ ".dot",
to_dot(CG, Dot_File),
Command = io_lib:format("dot -Tps ~s -o ~s ~s", [Args, File, Dot_File]),
_ = os:cmd(Command),
ok.
%-------------------------------------------------------------------------------
-spec put_behaviour_api_calls([{mfa(), mfa()}], callgraph()) -> callgraph().
put_behaviour_api_calls(Calls, Callgraph) ->
Callgraph#callgraph{beh_api_calls = Calls}.
-spec get_behaviour_api_calls(callgraph()) -> [{mfa(), mfa()}].
get_behaviour_api_calls(Callgraph) ->
Callgraph#callgraph.beh_api_calls.
