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-rw-r--r--lib/compiler/doc/src/notes.xml17
-rw-r--r--lib/compiler/src/beam_block.erl98
-rw-r--r--lib/compiler/src/beam_dead.erl7
-rw-r--r--lib/compiler/src/beam_jump.erl22
-rw-r--r--lib/compiler/test/beam_block_SUITE.erl27
-rw-r--r--lib/compiler/test/beam_jump_SUITE.erl19
-rw-r--r--lib/compiler/test/match_SUITE.erl13
-rw-r--r--lib/compiler/vsn.mk2
8 files changed, 150 insertions, 55 deletions
diff --git a/lib/compiler/doc/src/notes.xml b/lib/compiler/doc/src/notes.xml
index e25cdc580c..92b3d809fc 100644
--- a/lib/compiler/doc/src/notes.xml
+++ b/lib/compiler/doc/src/notes.xml
@@ -32,6 +32,23 @@
<p>This document describes the changes made to the Compiler
application.</p>
+<section><title>Compiler 7.0.1</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ A literal binary matching regression was introduced in
+ 19.0 where a match could fail to resolve to the right
+ clause. This has now been fixed.</p>
+ <p>
+ Own Id: OTP-13738</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
<section><title>Compiler 7.0</title>
<section><title>Fixed Bugs and Malfunctions</title>
diff --git a/lib/compiler/src/beam_block.erl b/lib/compiler/src/beam_block.erl
index 85d332c56e..ec41925beb 100644
--- a/lib/compiler/src/beam_block.erl
+++ b/lib/compiler/src/beam_block.erl
@@ -159,14 +159,43 @@ find_fixpoint(OptFun, Is0) ->
end.
%% move_allocates(Is0) -> Is
-%% Move allocate instructions upwards in the instruction stream, in the
-%% hope of getting more possibilities for optimizing away moves later.
+%% Move allocate instructions upwards in the instruction stream
+%% (within the same block), in the hope of getting more possibilities
+%% for optimizing away moves later.
%%
-%% NOTE: Moving allocation instructions is only safe because it is done
-%% immediately after code generation so that we KNOW that if {x,X} is
-%% initialized, all x registers with lower numbers are also initialized.
-%% That assumption may not be true after other optimizations, such as
-%% the beam_utils:live_opt/1 optimization.
+%% For example, we can transform the following instructions:
+%%
+%% get_tuple_element x(1) Element => x(2)
+%% allocate_zero StackSize 3 %% x(0), x(1), x(2) are live
+%%
+%% to the following instructions:
+%%
+%% allocate_zero StackSize 2 %% x(0) and x(1) are live
+%% get_tuple_element x(1) Element => x(2)
+%%
+%% NOTE: Since the beam_reorder pass has been run, it is no longer
+%% safe to assume that if x(N) is initialized, then all lower-numbered
+%% x registers are also initialized.
+%%
+%% For example, in general it is not safe to transform the following
+%% instructions:
+%%
+%% get_tuple_element x(0) Element => x(1)
+%% allocate_zero StackSize 3 %x(0), x(1), x(2) are live
+%%
+%% to the following instructions:
+%%
+%% allocate_zero StackSize 3
+%% get_tuple_element x(0) Element => x(1)
+%%
+%% The transformation is safe if and only if x(1) has been
+%% initialized previously. Unfortunately, beam_reorder may have moved
+%% a get_tuple_element instruction so that x(1) is not always
+%% initialized when this code is reached. To find whether or not x(1)
+%% is initialized, we would need to analyze all code preceding these
+%% two instructions (across branches). Since we currently don't have
+%% any practical mechanism for doing that, we will have to
+%% conservatively assume that the transformation is unsafe.
move_allocates([{block,Bl0}|Is]) ->
Bl = move_allocates_1(reverse(Bl0), []),
@@ -175,27 +204,19 @@ move_allocates([I|Is]) ->
[I|move_allocates(Is)];
move_allocates([]) -> [].
-move_allocates_1([{set,[],[],{alloc,_,_}=Alloc}|Is0], Acc0) ->
- {Is,Acc} = move_allocates_2(Alloc, Is0, Acc0),
- move_allocates_1(Is, Acc);
+move_allocates_1([I|Is], [{set,[],[],{alloc,Live0,Info}}|Acc]=Acc0) ->
+ case {alloc_may_pass(I),alloc_live_regs(I, Live0)} of
+ {false,_} ->
+ move_allocates_1(Is, [I|Acc0]);
+ {true,not_possible} ->
+ move_allocates_1(Is, [I|Acc0]);
+ {true,Live} when is_integer(Live) ->
+ A = {set,[],[],{alloc,Live,Info}},
+ move_allocates_1(Is, [A,I|Acc])
+ end;
move_allocates_1([I|Is], Acc) ->
move_allocates_1(Is, [I|Acc]);
-move_allocates_1([], Is) -> Is.
-
-move_allocates_2({alloc,Live,Info}, [{set,[],[],{alloc,Live0,Info0}}|Is], Acc) ->
- Live = Live0, % Assertion.
- Alloc = {alloc,Live,combine_alloc(Info0, Info)},
- move_allocates_2(Alloc, Is, Acc);
-move_allocates_2({alloc,Live,Info}=Alloc0, [I|Is]=Is0, Acc) ->
- case alloc_may_pass(I) of
- false ->
- {Is0,[{set,[],[],Alloc0}|Acc]};
- true ->
- Alloc = {alloc,alloc_live_regs(I, Live),Info},
- move_allocates_2(Alloc, Is, [I|Acc])
- end;
-move_allocates_2(Alloc, [], Acc) ->
- {[],[{set,[],[],Alloc}|Acc]}.
+move_allocates_1([], Acc) -> Acc.
alloc_may_pass({set,_,_,{alloc,_,_}}) -> false;
alloc_may_pass({set,_,_,{set_tuple_element,_}}) -> false;
@@ -204,9 +225,6 @@ alloc_may_pass({set,_,_,put_list}) -> false;
alloc_may_pass({set,_,_,put}) -> false;
alloc_may_pass({set,_,_,_}) -> true.
-combine_alloc({_,Ns,Nh1,Init}, {_,nostack,Nh2,[]}) ->
- {zero,Ns,beam_utils:combine_heap_needs(Nh1, Nh2),Init}.
-
%% opt([Instruction]) -> [Instruction]
%% Optimize the instruction stream inside a basic block.
@@ -393,10 +411,19 @@ eliminate_use_of_from_reg([I]=Is, From, _To, Acc) ->
%% opt_alloc(Instructions) -> Instructions'
%% Optimises all allocate instructions.
+opt_alloc([{set,[],[],{alloc,Live0,Info0}},
+ {set,[],[],{alloc,Live,Info}}|Is]) ->
+ Live = Live0, %Assertion.
+ Alloc = combine_alloc(Info0, Info),
+ I = {set,[],[],{alloc,Live,Alloc}},
+ opt_alloc([I|Is]);
opt_alloc([{set,[],[],{alloc,R,{_,Ns,Nh,[]}}}|Is]) ->
[{set,[],[],opt_alloc(Is, Ns, Nh, R)}|Is];
opt_alloc([I|Is]) -> [I|opt_alloc(Is)];
opt_alloc([]) -> [].
+
+combine_alloc({_,Ns,Nh1,Init}, {_,nostack,Nh2,[]}) ->
+ {zero,Ns,beam_utils:combine_heap_needs(Nh1, Nh2),Init}.
%% opt_alloc(Instructions, FrameSize, HeapNeed, LivingRegs) -> [Instr]
%% Generates the optimal sequence of instructions for
@@ -445,13 +472,14 @@ count_ones(Bits, Acc) ->
alloc_live_regs({set,Ds,Ss,_}, Regs0) ->
Rset = x_live(Ss, x_dead(Ds, (1 bsl Regs0)-1)),
- live_regs(Rset).
+ live_regs(0, Rset).
-live_regs(Regs) ->
- live_regs_1(0, Regs).
-
-live_regs_1(N, 0) -> N;
-live_regs_1(N, Regs) -> live_regs_1(N+1, Regs bsr 1).
+live_regs(N, 0) ->
+ N;
+live_regs(N, Regs) when Regs band 1 =:= 1 ->
+ live_regs(N+1, Regs bsr 1);
+live_regs(_, _) ->
+ not_possible.
x_dead([{x,N}|Rs], Regs) -> x_dead(Rs, Regs band (bnot (1 bsl N)));
x_dead([_|Rs], Regs) -> x_dead(Rs, Regs);
diff --git a/lib/compiler/src/beam_dead.erl b/lib/compiler/src/beam_dead.erl
index b01f58f683..6f6d742293 100644
--- a/lib/compiler/src/beam_dead.erl
+++ b/lib/compiler/src/beam_dead.erl
@@ -272,17 +272,14 @@ backward([{jump,{f,To}}=J|[{bif,Op,_,Ops,Reg}|Is]=Is0], D, Acc) ->
catch
throw:not_possible -> backward(Is0, D, [J|Acc])
end;
-backward([{test,bs_start_match2,F,Live,[R,_]=Args,Ctxt}|Is], D,
+backward([{test,bs_start_match2,F,_,[R,_],Ctxt}=I|Is], D,
[{test,bs_match_string,F,[Ctxt,Bs]},
{test,bs_test_tail2,F,[Ctxt,0]}|Acc0]=Acc) ->
- {f,To0} = F,
- To = shortcut_bs_start_match(To0, R, D),
case beam_utils:is_killed(Ctxt, Acc0, D) of
true ->
- Eq = {test,is_eq_exact,{f,To},[R,{literal,Bs}]},
+ Eq = {test,is_eq_exact,F,[R,{literal,Bs}]},
backward(Is, D, [Eq|Acc0]);
false ->
- I = {test,bs_start_match2,{f,To},Live,Args,Ctxt},
backward(Is, D, [I|Acc])
end;
backward([{test,bs_start_match2,{f,To0},Live,[Src|_]=Info,Dst}|Is], D, Acc) ->
diff --git a/lib/compiler/src/beam_jump.erl b/lib/compiler/src/beam_jump.erl
index 09cd3aa2d4..48b5a32814 100644
--- a/lib/compiler/src/beam_jump.erl
+++ b/lib/compiler/src/beam_jump.erl
@@ -167,12 +167,18 @@ share_1([{label,L}=Lbl|Is], Dict0, Seq, Acc) ->
end;
share_1([{func_info,_,_,_}=I|Is], _, [], Acc) ->
reverse(Is, [I|Acc]);
+share_1([{'catch',_,_}=I|Is], Dict0, Seq, Acc) ->
+ Dict = clean_non_sharable(Dict0),
+ share_1(Is, Dict, [I|Seq], 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([{catch_end,_}=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 ->
@@ -182,18 +188,18 @@ share_1([I|Is], Dict, Seq, 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.
+ %% We are passing in or out of a 'catch' or 'try' block. Remove
+ %% sequences that should not be shared over the boundaries of the
+ %% block. Since the end of the sequence must match, the only
+ %% possible match between a sequence outside and a sequence inside
+ %% the 'catch'/'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.
maps: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
+ %% match a sequence on the other side of the 'catch'/'try' block
%% boundary.
false;
sharable_with_try([_|Is]) ->
diff --git a/lib/compiler/test/beam_block_SUITE.erl b/lib/compiler/test/beam_block_SUITE.erl
index 4bcb252833..9fcb6e497d 100644
--- a/lib/compiler/test/beam_block_SUITE.erl
+++ b/lib/compiler/test/beam_block_SUITE.erl
@@ -21,7 +21,8 @@
-export([all/0,suite/0,groups/0,init_per_suite/1,end_per_suite/1,
init_per_group/2,end_per_group/2,
- get_map_elements/1,otp_7345/1,move_opt_across_gc_bif/1]).
+ get_map_elements/1,otp_7345/1,move_opt_across_gc_bif/1,
+ erl_202/1]).
%% The only test for the following functions is that
%% the code compiles and is accepted by beam_validator.
@@ -37,7 +38,8 @@ groups() ->
[{p,[parallel],
[get_map_elements,
otp_7345,
- move_opt_across_gc_bif
+ move_opt_across_gc_bif,
+ erl_202
]}].
init_per_suite(Config) ->
@@ -135,6 +137,27 @@ positive(speaking) ->
paris([], P) -> P + 1.
+
+%% See https://bugs.erlang.org/browse/ERL-202.
+%% Test that move_allocates/1 in beam_block doesn't move allocate
+%% when it would not be safe.
+
+-record(erl_202_r1, {y}).
+-record(erl_202_r2, {x}).
+
+erl_202(_Config) ->
+ Ref = make_ref(),
+ Ref = erl_202({{1,2},Ref}, 42),
+
+ {Ref} = erl_202({7,8}, #erl_202_r1{y=#erl_202_r2{x=Ref}}),
+
+ ok.
+
+erl_202({{_, _},X}, _) ->
+ X;
+erl_202({_, _}, #erl_202_r1{y=R2}) ->
+ {R2#erl_202_r2.x}.
+
%%%
%%% The only test of the following code is that it compiles.
%%%
diff --git a/lib/compiler/test/beam_jump_SUITE.erl b/lib/compiler/test/beam_jump_SUITE.erl
index 0b13adaff2..088f63606c 100644
--- a/lib/compiler/test/beam_jump_SUITE.erl
+++ b/lib/compiler/test/beam_jump_SUITE.erl
@@ -21,7 +21,7 @@
-export([all/0,suite/0,groups/0,init_per_suite/1,end_per_suite/1,
init_per_group/2,end_per_group/2,
- undefined_label/1]).
+ undefined_label/1,ambiguous_catch_try_state/1]).
suite() ->
[{ct_hooks,[ts_install_cth]}].
@@ -32,7 +32,8 @@ all() ->
groups() ->
[{p,[parallel],
- [undefined_label
+ [undefined_label,
+ ambiguous_catch_try_state
]}].
init_per_suite(Config) ->
@@ -57,3 +58,17 @@ flights(0, [], []) when [], 0; 0.0, [], false ->
clark;
flights(_, Reproduction, introduction) when false, Reproduction ->
responsible.
+
+%% [ERL-209] beam_jump would share 'catch' blocks, causing an
+%% ambiguous_catch_try_state error in beam_validator.
+
+ambiguous_catch_try_state(_Config) ->
+ {{'EXIT',{{case_clause,song},_}},{'EXIT',{{case_clause,song},_}}} =
+ checks(42),
+ ok.
+
+river() -> song.
+
+checks(Wanted) ->
+ %% Must be one line to cause the unsafe optimization.
+ {catch case river() of sheet -> begin +Wanted, if "da" -> Wanted end end end, catch case river() of sheet -> begin + Wanted, if "da" -> Wanted end end end}.
diff --git a/lib/compiler/test/match_SUITE.erl b/lib/compiler/test/match_SUITE.erl
index 31402ac717..127679ba69 100644
--- a/lib/compiler/test/match_SUITE.erl
+++ b/lib/compiler/test/match_SUITE.erl
@@ -24,7 +24,7 @@
pmatch/1,mixed/1,aliases/1,non_matching_aliases/1,
match_in_call/1,untuplify/1,shortcut_boolean/1,letify_guard/1,
selectify/1,underscore/1,match_map/1,map_vars_used/1,
- coverage/1,grab_bag/1]).
+ coverage/1,grab_bag/1,literal_binary/1]).
-include_lib("common_test/include/ct.hrl").
@@ -40,7 +40,7 @@ groups() ->
match_in_call,untuplify,
shortcut_boolean,letify_guard,selectify,
underscore,match_map,map_vars_used,coverage,
- grab_bag]}].
+ grab_bag,literal_binary]}].
init_per_suite(Config) ->
@@ -574,6 +574,15 @@ grab_bag_remove_failure([{stretch,_,Mi}=Stretch | Specs], Unit, _MaxFailure) ->
ok
end.
+%% Regression in 19.0, reported by Alexei Sholik
+literal_binary(_Config) ->
+ 3 = literal_binary_match(bar,<<"y">>),
+ ok.
+
+literal_binary_match(bar, <<"x">>) -> 1;
+literal_binary_match(_, <<"x">>) -> 2;
+literal_binary_match(_, <<"y">>) -> 3;
+literal_binary_match(_, _) -> fail.
id(I) -> I.
diff --git a/lib/compiler/vsn.mk b/lib/compiler/vsn.mk
index 23dd4bd4b1..334784657e 100644
--- a/lib/compiler/vsn.mk
+++ b/lib/compiler/vsn.mk
@@ -1 +1 @@
-COMPILER_VSN = 7.0
+COMPILER_VSN = 7.0.1