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-rw-r--r--lib/compiler/src/beam_receive.erl146
1 files changed, 83 insertions, 63 deletions
diff --git a/lib/compiler/src/beam_receive.erl b/lib/compiler/src/beam_receive.erl
index bd1f44f66b..97a9188ee7 100644
--- a/lib/compiler/src/beam_receive.erl
+++ b/lib/compiler/src/beam_receive.erl
@@ -1,7 +1,7 @@
%%
%% %CopyrightBegin%
%%
-%% Copyright Ericsson AB 2010-2011. All Rights Reserved.
+%% Copyright Ericsson AB 2010-2013. 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
@@ -84,13 +84,29 @@ function({function,Name,Arity,Entry,Is}) ->
erlang:raise(Class, Error, Stack)
end.
+opt([{call_ext,A,{extfunc,erlang,spawn_monitor,A}}=I0|Is0], D, Acc)
+ when A =:= 1; A =:= 3 ->
+ case ref_in_tuple(Is0) of
+ no ->
+ opt(Is0, D, [I0|Acc]);
+ {yes,Regs,Is1,MatchReversed} ->
+ %% The call creates a brand new reference. Now
+ %% search for a receive statement in the same
+ %% function that will match against the reference.
+ case opt_recv(Is1, Regs, D) of
+ no ->
+ opt(Is0, D, [I0|Acc]);
+ {yes,Is,Lbl} ->
+ opt(Is, D, MatchReversed++[I0,{recv_mark,{f,Lbl}}|Acc])
+ end
+ end;
opt([{call_ext,Arity,{extfunc,erlang,Name,Arity}}=I|Is0], D, Acc) ->
case creates_new_ref(Name, Arity) of
true ->
%% The call creates a brand new reference. Now
%% search for a receive statement in the same
%% function that will match against the reference.
- case opt_recv(Is0, D) of
+ case opt_recv(Is0, regs_init_x0(), D) of
no ->
opt(Is0, D, [I|Acc]);
{yes,Is,Lbl} ->
@@ -104,36 +120,51 @@ opt([I|Is], D, Acc) ->
opt([], _, Acc) ->
reverse(Acc).
+ref_in_tuple([{test,is_tuple,_,[{x,0}]}=I1,
+ {test,test_arity,_,[{x,0},2]}=I2,
+ {block,[{set,[_],[{x,0}],{get_tuple_element,0}},
+ {set,[Dst],[{x,0}],{get_tuple_element,1}}|Bl]}=I3|Is]) ->
+ ref_in_tuple_1(Bl, Dst, Is, [I3,I2,I1]);
+ref_in_tuple([{test,is_tuple,_,[{x,0}]}=I1,
+ {test,test_arity,_,[{x,0},2]}=I2,
+ {block,[{set,[Dst],[{x,0}],{get_tuple_element,1}}|Bl]}=I3|Is]) ->
+ ref_in_tuple_1(Bl, Dst, Is, [I3,I2,I1]);
+ref_in_tuple(_) -> no.
+
+ref_in_tuple_1(Bl, Dst, Is, MatchReversed) ->
+ Regs0 = regs_init_singleton(Dst),
+ Regs = opt_update_regs_bl(Bl, Regs0),
+ {yes,Regs,Is,MatchReversed}.
+
%% creates_new_ref(Name, Arity) -> true|false.
%% Return 'true' if the BIF Name/Arity will create a new reference.
creates_new_ref(monitor, 2) -> true;
creates_new_ref(make_ref, 0) -> true;
creates_new_ref(_, _) -> false.
-%% opt_recv([Instruction], LabelIndex) -> no|{yes,[Instruction]}
+%% opt_recv([Instruction], Regs, LabelIndex) -> no|{yes,[Instruction]}
%% Search for a receive statement that will only retrieve messages
%% that contain the newly created reference (which is currently in {x,0}).
-opt_recv(Is, D) ->
- R = regs_init_x0(),
+opt_recv(Is, Regs, D) ->
L = gb_sets:empty(),
- opt_recv(Is, D, R, L, []).
+ opt_recv(Is, D, Regs, L, []).
opt_recv([{label,L}=Lbl,{loop_rec,{f,Fail},_}=Loop|Is], D, R0, _, Acc) ->
R = regs_kill_not_live(0, R0),
- case regs_to_list(R) of
- [{y,_}=RefReg] ->
- %% We now have the new reference in the Y register RefReg
+ case regs_empty(R) of
+ false ->
+ %% We now have the new reference in Y registers
%% and the current instruction is the beginning of a
%% receive statement. We must now verify that only messages
%% that contain the reference will be matched.
- case opt_ref_used(Is, RefReg, Fail, D) of
+ case opt_ref_used(Is, R, Fail, D) of
false ->
no;
true ->
RecvSet = {recv_set,{f,L}},
{yes,reverse(Acc, [RecvSet,Lbl,Loop|Is]),L}
end;
- [] ->
+ true ->
no
end;
opt_recv([I|Is], D, R0, L0, Acc) ->
@@ -157,8 +188,6 @@ opt_update_regs({call_fun,_}, R, L) ->
{regs_kill_not_live(0, R),L};
opt_update_regs({kill,Y}, R, L) ->
{regs_kill([Y], R),L};
-opt_update_regs(send, R, L) ->
- {regs_kill_not_live(0, R),L};
opt_update_regs({'catch',_,{f,Lbl}}, R, L) ->
{R,gb_sets:add(Lbl, L)};
opt_update_regs({catch_end,_}, R, L) ->
@@ -197,9 +226,9 @@ opt_update_regs_bl([{set,Ds,_,_}|Is], Regs0) ->
opt_update_regs_bl(Is, Regs);
opt_update_regs_bl([], Regs) -> Regs.
-%% opt_ref_used([Instruction], RefRegister, FailLabel, LabelIndex) -> true|false
+%% opt_ref_used([Instruction], RefRegs, FailLabel, LabelIndex) -> true|false
%% Return 'true' if it is certain that only messages that contain the same
-%% reference as in RefRegister can be matched out. Otherwise return 'false'.
+%% reference as in RefRegs can be matched out. Otherwise return 'false'.
%%
%% Basically, we follow all possible paths through the receive statement.
%% If all paths are safe, we return 'true'.
@@ -207,7 +236,7 @@ opt_update_regs_bl([], Regs) -> Regs.
%% A branch to FailLabel is safe, because it exits the receive statement
%% and no further message may be matched out.
%%
-%% If a path hits an comparision between RefRegister and part of the message,
+%% If a path hits an comparision between RefRegs and part of the message,
%% that path is safe (any messages that may be matched further down the
%% path is guaranteed to contain the reference).
%%
@@ -216,11 +245,11 @@ opt_update_regs_bl([], Regs) -> Regs.
%% we hit an unrecognized instruction, we also give up and return
%% 'false' (the optimization may be unsafe).
-opt_ref_used(Is, RefReg, Fail, D) ->
+opt_ref_used(Is, RefRegs, Fail, D) ->
Done = gb_sets:singleton(Fail),
Regs = regs_init_x0(),
try
- opt_ref_used_1(Is, RefReg, D, Done, Regs),
+ _ = opt_ref_used_1(Is, RefRegs, D, Done, Regs),
true
catch
throw:not_used ->
@@ -229,40 +258,39 @@ opt_ref_used(Is, RefReg, Fail, D) ->
%% This functions only returns if all paths through the receive
%% statement are safe, and throws an 'not_used' term otherwise.
-opt_ref_used_1([{block,Bl}|Is], RefReg, D, Done, Regs0) ->
+opt_ref_used_1([{block,Bl}|Is], RefRegs, D, Done, Regs0) ->
Regs = opt_ref_used_bl(Bl, Regs0),
- opt_ref_used_1(Is, RefReg, D, Done, Regs);
-opt_ref_used_1([{test,is_eq_exact,{f,Fail},Args}|Is], RefReg, D, Done0, Regs) ->
- Done = opt_ref_used_at(Fail, RefReg, D, Done0, Regs),
- case is_ref_msg_comparison(Args, RefReg, Regs) of
+ opt_ref_used_1(Is, RefRegs, D, Done, Regs);
+opt_ref_used_1([{test,is_eq_exact,{f,Fail},Args}|Is],
+ RefRegs, D, Done0, Regs) ->
+ Done = opt_ref_used_at(Fail, RefRegs, D, Done0, Regs),
+ case is_ref_msg_comparison(Args, RefRegs, Regs) of
false ->
- opt_ref_used_1(Is, RefReg, D, Done, Regs);
+ opt_ref_used_1(Is, RefRegs, D, Done, Regs);
true ->
%% The instructions that follow (Is) can only be executed
- %% if the message contains the same reference as in RefReg.
+ %% if the message contains the same reference as in RefRegs.
Done
end;
-opt_ref_used_1([{test,is_ne_exact,{f,Fail},Args}|Is], RefReg, D, Done0, Regs) ->
- Done = opt_ref_used_1(Is, RefReg, D, Done0, Regs),
- case is_ref_msg_comparison(Args, RefReg, Regs) of
+opt_ref_used_1([{test,is_ne_exact,{f,Fail},Args}|Is],
+ RefRegs, D, Done0, Regs) ->
+ Done = opt_ref_used_1(Is, RefRegs, D, Done0, Regs),
+ case is_ref_msg_comparison(Args, RefRegs, Regs) of
false ->
- opt_ref_used_at(Fail, RefReg, D, Done, Regs);
+ opt_ref_used_at(Fail, RefRegs, D, Done, Regs);
true ->
Done
end;
-opt_ref_used_1([{test,_,{f,Fail},_}|Is], RefReg, D, Done0, Regs) ->
- Done = opt_ref_used_at(Fail, RefReg, D, Done0, Regs),
- opt_ref_used_1(Is, RefReg, D, Done, Regs);
-opt_ref_used_1([{select_tuple_arity,_,{f,Fail},{list,List}}|_], RefReg, D, Done, Regs) ->
- Lbls = [F || {f,F} <- List] ++ [Fail],
- opt_ref_used_in_all(Lbls, RefReg, D, Done, Regs);
-opt_ref_used_1([{select_val,_,{f,Fail},{list,List}}|_], RefReg, D, Done, Regs) ->
+opt_ref_used_1([{test,_,{f,Fail},_}|Is], RefRegs, D, Done0, Regs) ->
+ Done = opt_ref_used_at(Fail, RefRegs, D, Done0, Regs),
+ opt_ref_used_1(Is, RefRegs, D, Done, Regs);
+opt_ref_used_1([{select,_,_,{f,Fail},List}|_], RefRegs, D, Done, Regs) ->
Lbls = [F || {f,F} <- List] ++ [Fail],
- opt_ref_used_in_all(Lbls, RefReg, D, Done, Regs);
-opt_ref_used_1([{label,Lbl}|Is], RefReg, D, Done, Regs) ->
+ opt_ref_used_in_all(Lbls, RefRegs, D, Done, Regs);
+opt_ref_used_1([{label,Lbl}|Is], RefRegs, D, Done, Regs) ->
case gb_sets:is_member(Lbl, Done) of
true -> Done;
- false -> opt_ref_used_1(Is, RefReg, D, Done, Regs)
+ false -> opt_ref_used_1(Is, RefRegs, D, Done, Regs)
end;
opt_ref_used_1([{loop_rec_end,_}|_], _, _, Done, _) ->
Done;
@@ -270,27 +298,25 @@ opt_ref_used_1([_I|_], _RefReg, _D, _Done, _Regs) ->
%% The optimization may be unsafe.
throw(not_used).
-%% is_ref_msg_comparison(Args, RefReg, RegisterSet) -> true|false.
+%% is_ref_msg_comparison(Args, RefRegs, RegisterSet) -> true|false.
%% Return 'true' if Args denotes a comparison between the
%% reference and message or part of the message.
-is_ref_msg_comparison([R,RefReg], RefReg, Regs) ->
- regs_is_member(R, Regs);
-is_ref_msg_comparison([RefReg,R], RefReg, Regs) ->
- regs_is_member(R, Regs);
-is_ref_msg_comparison([_,_], _, _) -> false.
-
-opt_ref_used_in_all([L|Ls], RefReg, D, Done0, Regs) ->
- Done = opt_ref_used_at(L, RefReg, D, Done0, Regs),
- opt_ref_used_in_all(Ls, RefReg, D, Done, Regs);
+is_ref_msg_comparison([R1,R2], RefRegs, Regs) ->
+ (regs_is_member(R2, RefRegs) andalso regs_is_member(R1, Regs)) orelse
+ (regs_is_member(R1, RefRegs) andalso regs_is_member(R2, Regs)).
+
+opt_ref_used_in_all([L|Ls], RefRegs, D, Done0, Regs) ->
+ Done = opt_ref_used_at(L, RefRegs, D, Done0, Regs),
+ opt_ref_used_in_all(Ls, RefRegs, D, Done, Regs);
opt_ref_used_in_all([], _, _, Done, _) -> Done.
-opt_ref_used_at(Fail, RefReg, D, Done0, Regs) ->
+opt_ref_used_at(Fail, RefRegs, D, Done0, Regs) ->
case gb_sets:is_member(Fail, Done0) of
true ->
Done0;
false ->
Is = beam_utils:code_at(Fail, D),
- Done = opt_ref_used_1(Is, RefReg, D, Done0, Regs),
+ Done = opt_ref_used_1(Is, RefRegs, D, Done0, Regs),
gb_sets:add(Fail, Done)
end.
@@ -323,6 +349,12 @@ opt_ref_used_bl([], Regs) -> Regs.
regs_init() ->
{0,0}.
+%% regs_init_singleton(Register) -> RegisterSet
+%% Return a set that only contains one register.
+
+regs_init_singleton(Reg) ->
+ regs_add(Reg, regs_init()).
+
%% regs_init_x0() -> RegisterSet
%% Return a set that only contains the {x,0} register.
@@ -376,15 +408,3 @@ regs_all_members([], _) -> true.
regs_is_member({x,N}, {Regs,_}) -> Regs band (1 bsl N) =/= 0;
regs_is_member({y,N}, {_,Regs}) -> Regs band (1 bsl N) =/= 0;
regs_is_member(_, _) -> false.
-
-%% regs_to_list(RegisterSet) -> [Register]
-%% Convert the register set to an explicit list of registers.
-regs_to_list({Xregs,Yregs}) ->
- regs_to_list_1(Xregs, 0, x, regs_to_list_1(Yregs, 0, y, [])).
-
-regs_to_list_1(0, _, _, Acc) ->
- Acc;
-regs_to_list_1(Regs, N, Tag, Acc) when (Regs band 1) =:= 1 ->
- regs_to_list_1(Regs bsr 1, N+1, Tag, [{Tag,N}|Acc]);
-regs_to_list_1(Regs, N, Tag, Acc) ->
- regs_to_list_1(Regs bsr 1, N+1, Tag, Acc).
generated by cgit v1.2.3 (git 2.25.1) at 2025-01-07 03:08:54 +0000