%% -*- 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 %%% Description : %%% %%% Created : 30 Mar 2005 by Tobias Lindahl %%%------------------------------------------------------------------- -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.