Merge branch 'maint'

* maint: beam_ssa_codegen: Ensure that indexes are unique in update_record
erlang · Oct 4, 2024 · 0354caf · 0354caf
2 parents 0c610c9 + 4afa158
commit 0354caf
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Showing 2 changed files with 25 additions and 8 deletions.
diff --git a/lib/compiler/src/beam_ssa_codegen.erl b/lib/compiler/src/beam_ssa_codegen.erl
@@ -1378,7 +1378,7 @@ cg_block([#cg_set{op=update_record,dst=Dst0,args=Args0,anno=Anno}|T], Context, S
     Args = typed_args(Args0, Anno, St0),
     Dst = beam_arg(Dst0, St0),
     [Hint,{integer,Size},Src|Ss0] = Args,
-    Ss = cg_update_record_list(Ss0, []),
+    Ss = cg_update_record_list(Ss0),
     I = {update_record,Hint,Size,Src,Dst,{list,Ss}},
     {Is1,St} = cg_block(T, Context, St0),
     {[I|Is1],St};
@@ -1916,12 +1916,15 @@ cg_test(raw_raise, _Fail, Args, Dst, _I) ->
 cg_test(resume, _Fail, [_,_]=Args, Dst, _I) ->
     cg_instr(resume, Args, Dst).
 
-cg_update_record_list([{integer, Index}, Value], []) ->
+cg_update_record_list([{integer, Index}, Value]) ->
     [Index, Value];
-cg_update_record_list([{integer, Index}, Value | Updates], Acc) ->
-    cg_update_record_list(Updates, [{Index, Value} | Acc]);
-cg_update_record_list([], Acc) ->
-    append([[Index, Value] || {Index, Value} <- sort(Acc)]).
+cg_update_record_list([_,_|_]=Updates) ->
+    cg_update_record_list_1(Updates, #{}).
+
+cg_update_record_list_1([{integer, Index}, Value | Updates], Acc) ->
+    cg_update_record_list_1(Updates, Acc#{ Index => Value });
+cg_update_record_list_1([], Acc) ->
+    append([[Index, Value] || Index := Value <- maps:iterator(Acc, ordered)]).
 
 cg_bs_get(Fail, #cg_set{dst=Dst0,args=Args,anno=Anno}=Set, St) ->
     [{atom,Type}|Ss0] = typed_args(Args, Anno, St),

diff --git a/lib/compiler/test/record_SUITE.erl b/lib/compiler/test/record_SUITE.erl
@@ -29,7 +29,7 @@
 	 errors/1,record_test_2/1,record_test_3/1,record_access_in_guards/1,
 	 guard_opt/1,eval_once/1,foobar/1,missing_test_heap/1,
 	 nested_access/1,coverage/1,grab_bag/1,slow_compilation/1,
-         record_updates/1]).
+         record_updates/1, duplicate_update_record/1]).
 
 init_per_testcase(_Case, Config) ->
     Config.
@@ -49,7 +49,7 @@ groups() ->
       [errors,record_test_2,record_test_3,
        record_access_in_guards,guard_opt,eval_once,foobar,
        missing_test_heap,nested_access,coverage,grab_bag,
-       slow_compilation,record_updates]}].
+       slow_compilation,record_updates, duplicate_update_record]}].
 
 
 init_per_suite(Config) ->
@@ -845,6 +845,20 @@ record_updates(_Config) ->
 
     ok.
 
+%% GH-8783: Duplicate indexes in update_record crashed the emulator.
+duplicate_update_record(Config) when is_list(Config) ->
+    DuplicateUR0 = id({id(left), id(right)}),
+    {_, _} = DuplicateUR0,
+
+    DuplicateUR1 = erlang:setelement(2, DuplicateUR0, false),
+    DuplicateUR = erlang:setelement(2, DuplicateUR1, false),
+    {'EXIT', _} = catch duplicate_update_record_1(DuplicateUR),
+
+    ok.
+
+duplicate_update_record_1(_) ->
+    erlang:error(crash).
+
 %%%
 %%% Common utilities.
 %%%