From b66193afc3fe85072da4631c52c5ccec136caa05 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Bj=C3=B6rn=20Gustavsson?= Date: Wed, 23 Sep 2015 12:30:16 +0200 Subject: beam_type: Improve optimizations by keeping track of booleans There is an optimization in beam_block to simplify a select_val on a known boolean value. We can implement this optimization in a cleaner way in beam_type and it will also be applicable in more situations. (When I added the optimization to beam_type without removing the optimization from beam_block, the optimization was applied 66 times.) --- lib/compiler/src/beam_block.erl | 34 ---------------------------------- lib/compiler/src/beam_type.erl | 28 ++++++++++++++++++++++++++++ lib/compiler/test/beam_type_SUITE.erl | 15 +++++++++++++-- 3 files changed, 41 insertions(+), 36 deletions(-) (limited to 'lib') diff --git a/lib/compiler/src/beam_block.erl b/lib/compiler/src/beam_block.erl index 741fdbb973..10dbaf462c 100644 --- a/lib/compiler/src/beam_block.erl +++ b/lib/compiler/src/beam_block.erl @@ -58,33 +58,6 @@ blockify(Is) -> blockify([{loop_rec,{f,Fail},{x,0}},{loop_rec_end,_Lbl},{label,Fail}|Is], Acc) -> %% Useless instruction sequence. blockify(Is, Acc); -blockify([{test,is_atom,{f,Fail},[Reg]}=I| - [{select,select_val,Reg,{f,Fail}, - [{atom,false},{f,_}=BrFalse, - {atom,true}=AtomTrue,{f,_}=BrTrue]}|Is]=Is0], - [{block,Bl}|_]=Acc) -> - case is_last_bool(Bl, Reg) of - false -> - blockify(Is0, [I|Acc]); - true -> - %% The last instruction is a boolean operator/guard BIF that can't fail. - %% We can convert the three-way branch to a two-way branch (eliminating - %% the reference to the failure label). - blockify(Is, [{jump,BrTrue}, - {test,is_eq_exact,BrFalse,[Reg,AtomTrue]}|Acc]) - end; -blockify([{test,is_atom,{f,Fail},[Reg]}=I| - [{select,select_val,Reg,{f,Fail}, - [{atom,true}=AtomTrue,{f,_}=BrTrue, - {atom,false},{f,_}=BrFalse]}|Is]=Is0], - [{block,Bl}|_]=Acc) -> - case is_last_bool(Bl, Reg) of - false -> - blockify(Is0, [I|Acc]); - true -> - blockify(Is, [{jump,BrTrue}, - {test,is_eq_exact,BrFalse,[Reg,AtomTrue]}|Acc]) - end; blockify([I|Is0]=IsAll, Acc) -> case collect(I) of error -> blockify(Is0, [I|Acc]); @@ -94,13 +67,6 @@ blockify([I|Is0]=IsAll, Acc) -> end; blockify([], Acc) -> reverse(Acc). -is_last_bool([{set,[Reg],As,{bif,N,_}}], Reg) -> - Ar = length(As), - erl_internal:new_type_test(N, Ar) orelse erl_internal:comp_op(N, Ar) - orelse erl_internal:bool_op(N, Ar); -is_last_bool([_|Is], Reg) -> is_last_bool(Is, Reg); -is_last_bool([], _) -> false. - collect_block(Is) -> collect_block(Is, []). diff --git a/lib/compiler/src/beam_type.erl b/lib/compiler/src/beam_type.erl index 17ce7082f6..4b45c28623 100644 --- a/lib/compiler/src/beam_type.erl +++ b/lib/compiler/src/beam_type.erl @@ -95,6 +95,11 @@ simplify_basic_1([{set,[D],[TupleReg],{get_tuple_element,0}}=I|Is0], Ts0, Acc) - end; simplify_basic_1([{set,_,_,{try_catch,_,_}}=I|Is], _Ts, Acc) -> simplify_basic_1(Is, tdb_new(), [I|Acc]); +simplify_basic_1([{test,is_atom,_,[R]}=I|Is], Ts, Acc) -> + case tdb_find(R, Ts) of + boolean -> simplify_basic_1(Is, Ts, Acc); + _ -> simplify_basic_1(Is, Ts, [I|Acc]) + end; simplify_basic_1([{test,is_integer,_,[R]}=I|Is], Ts, Acc) -> case tdb_find(R, Ts) of integer -> simplify_basic_1(Is, Ts, Acc); @@ -148,6 +153,8 @@ simplify_basic_1([{select,select_val,Reg,_,_}=I0|Is], Ts, Acc) -> I = case tdb_find(Reg, Ts) of {integer,Range} -> simplify_select_val_int(I0, Range); + boolean -> + simplify_select_val_bool(I0); _ -> I0 end, @@ -166,6 +173,15 @@ simplify_select_val_int({select,select_val,R,_,L0}=I, {Min,Max}) -> true -> simplify_select_val_1(L0, {integer,Max}, R, []) end. +simplify_select_val_bool({select,select_val,R,_,L}=I) -> + Vs = sort([V || {atom,V} <- L]), + case Vs of + [false,true] -> + simplify_select_val_1(L, {atom,false}, R, []); + _ -> + I + end. + simplify_select_val_1([Val,F|T], Val, R, Acc) -> L = reverse(Acc, T), {select,select_val,R,F,L}; @@ -414,6 +430,17 @@ update({set,[D],[{integer,I},Reg],{bif,element,_}}, Ts0) -> tdb_update([{Reg,{tuple,I,[]}},{D,kill}], Ts0); update({set,[D],[_Index,Reg],{bif,element,_}}, Ts0) -> tdb_update([{Reg,{tuple,0,[]}},{D,kill}], Ts0); +update({set,[D],Args,{bif,N,_}}, Ts0) -> + Ar = length(Args), + BoolOp = erl_internal:new_type_test(N, Ar) orelse + erl_internal:comp_op(N, Ar) orelse + erl_internal:bool_op(N, Ar), + case BoolOp of + true -> + tdb_update([{D,boolean}], Ts0); + false -> + tdb_update([{D,kill}], Ts0) + end; update({set,[D],[S],{get_tuple_element,0}}, Ts) -> tdb_update([{D,{tuple_element,S,0}}], Ts); update({set,[D],[S],{alloc,_,{gc_bif,float,{f,0}}}}, Ts0) -> @@ -828,6 +855,7 @@ merge_type_info(NewType, _) -> verify_type(NewType), NewType. +verify_type(boolean) -> ok; verify_type(integer) -> ok; verify_type({integer,{Min,Max}}) when is_integer(Min), is_integer(Max) -> ok; diff --git a/lib/compiler/test/beam_type_SUITE.erl b/lib/compiler/test/beam_type_SUITE.erl index 8d99d76180..8d5c0190ed 100644 --- a/lib/compiler/test/beam_type_SUITE.erl +++ b/lib/compiler/test/beam_type_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, - integers/1,coverage/1]). + integers/1,coverage/1,booleans/1]). suite() -> [{ct_hooks,[ts_install_cth]}]. @@ -32,7 +32,8 @@ all() -> groups() -> [{p,[parallel], [integers, - coverage + coverage, + booleans ]}]. init_per_suite(Config) -> @@ -83,5 +84,15 @@ coverage(_Config) -> ok. +booleans(_Config) -> + {'EXIT',{{case_clause,_},_}} = (catch do_booleans(42)), + ok. + +do_booleans(B) -> + case is_integer(B) of + yes -> yes; + no -> no + end. + id(I) -> I. -- cgit v1.2.3