aboutsummaryrefslogtreecommitdiffstats
path: root/lib/compiler
diff options
context:
space:
mode:
authorBjörn Gustavsson <[email protected]>2015-02-19 13:34:22 +0100
committerBjörn Gustavsson <[email protected]>2015-02-20 08:02:09 +0100
commit1899aa487d898078e6e7b1c6b7ea3aa5ea31c7e5 (patch)
treebc2a1a4de544a527ee38805b5ee5811cdb7f8ed5 /lib/compiler
parent9d8327c62a981bcc436e5f9fc5466f5539dce3dc (diff)
downloadotp-1899aa487d898078e6e7b1c6b7ea3aa5ea31c7e5.tar.gz
otp-1899aa487d898078e6e7b1c6b7ea3aa5ea31c7e5.tar.bz2
otp-1899aa487d898078e6e7b1c6b7ea3aa5ea31c7e5.zip
beam_jump: Don't jump into the middle of a 'try'
The code sharing optimization could produce a jump into the middle of a 'try' block. beam_validator would reject the code. Reported-by: Ulf Norell
Diffstat (limited to 'lib/compiler')
-rw-r--r--lib/compiler/src/beam_jump.erl24
-rw-r--r--lib/compiler/test/trycatch_SUITE.erl17
2 files changed, 39 insertions, 2 deletions
diff --git a/lib/compiler/src/beam_jump.erl b/lib/compiler/src/beam_jump.erl
index 4e699c4fbf..f457aa1155 100644
--- a/lib/compiler/src/beam_jump.erl
+++ b/lib/compiler/src/beam_jump.erl
@@ -166,6 +166,12 @@ share_1([{label,L}=Lbl|Is], Dict0, Seq, Acc) ->
end;
share_1([{func_info,_,_,_}=I|Is], _, [], Acc) ->
reverse(Is, [I|Acc]);
+share_1([{'try',_,_}=I|Is], Dict0, Seq, Acc) ->
+ Dict = clean_non_sharable(Dict0),
+ share_1(Is, Dict, [I|Seq], Acc);
+share_1([{try_case,_}=I|Is], Dict0, Seq, Acc) ->
+ Dict = clean_non_sharable(Dict0),
+ share_1(Is, Dict, [I|Seq], Acc);
share_1([I|Is], Dict, Seq, Acc) ->
case is_unreachable_after(I) of
false ->
@@ -174,6 +180,24 @@ share_1([I|Is], Dict, Seq, Acc) ->
share_1(Is, Dict, [I], Acc)
end.
+clean_non_sharable(Dict) ->
+ %% We are passing in or out of a 'try' block. Remove
+ %% sequences that should not shared over the boundaries
+ %% of a 'try' block. Since the end of the sequence must match,
+ %% the only possible match between a sequence outside and
+ %% a sequence inside the 'try' block is a sequence that ends
+ %% with an instruction that causes an exception. Any sequence
+ %% that causes an exception must contain a line/1 instruction.
+ dict:filter(fun(K, _V) -> sharable_with_try(K) end, Dict).
+
+sharable_with_try([{line,_}|_]) ->
+ %% This sequence may cause an exception and may potentially
+ %% match a sequence on the other side of the 'try' block
+ %% boundary.
+ false;
+sharable_with_try([_|Is]) ->
+ sharable_with_try(Is);
+sharable_with_try([]) -> true.
%% Eliminate all fallthroughs. Return the result reversed.
diff --git a/lib/compiler/test/trycatch_SUITE.erl b/lib/compiler/test/trycatch_SUITE.erl
index 8ab618bb01..80d93fbfa4 100644
--- a/lib/compiler/test/trycatch_SUITE.erl
+++ b/lib/compiler/test/trycatch_SUITE.erl
@@ -24,7 +24,8 @@
catch_oops/1,after_oops/1,eclectic/1,rethrow/1,
nested_of/1,nested_catch/1,nested_after/1,
nested_horrid/1,last_call_optimization/1,bool/1,
- plain_catch_coverage/1,andalso_orelse/1,get_in_try/1]).
+ plain_catch_coverage/1,andalso_orelse/1,get_in_try/1,
+ hockey/1]).
-include_lib("test_server/include/test_server.hrl").
@@ -39,7 +40,8 @@ groups() ->
[basic,lean_throw,try_of,try_after,catch_oops,
after_oops,eclectic,rethrow,nested_of,nested_catch,
nested_after,nested_horrid,last_call_optimization,
- bool,plain_catch_coverage,andalso_orelse,get_in_try]}].
+ bool,plain_catch_coverage,andalso_orelse,get_in_try,
+ hockey]}].
init_per_suite(Config) ->
@@ -943,3 +945,14 @@ get_valid_line([_|T]=Path, Annotations) ->
_:not_found ->
get_valid_line(T, Annotations)
end.
+
+hockey(_) ->
+ {'EXIT',{{badmatch,_},[_|_]}} = (catch hockey()),
+ ok.
+
+hockey() ->
+ %% beam_jump used to generate a call into the try block.
+ %% beam_validator disapproved.
+ receive _ -> (b = fun() -> ok end)
+ + hockey, +x after 0 -> ok end, try (a = fun() -> ok end) + hockey, +
+ y catch _ -> ok end.