From 1781ebe6cd61d0bbd1f8c4e55b42edebfdc45734 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Bj=C3=B6rn=20Gustavsson?= Date: Fri, 19 Jan 2018 14:38:54 +0100 Subject: beam_type: Optimize away unnecessary test_unit instructions Optimize away unnecessary test_unit instructions that verify that binaries are byte-aligned. In a tight loop, eliminating an instruction can have a small but measurable improvement of the execution time. --- lib/compiler/src/beam_type.erl | 47 ++++++++++++++++++++++++++++++----- lib/compiler/test/beam_type_SUITE.erl | 42 +++++++++++++++++++++++++++++-- 2 files changed, 81 insertions(+), 8 deletions(-) diff --git a/lib/compiler/src/beam_type.erl b/lib/compiler/src/beam_type.erl index 576557d35d..b2fabed2c5 100644 --- a/lib/compiler/src/beam_type.erl +++ b/lib/compiler/src/beam_type.erl @@ -157,6 +157,21 @@ simplify_instr({select,select_val,Reg,_,_}=I, Ts) -> _ -> I end]; +simplify_instr({test,bs_test_unit,_,[Src,Unit]}=I, Ts) -> + case tdb_find(Src, Ts) of + {binary,U} when U rem Unit =:= 0 -> []; + _ -> [I] + end; +simplify_instr({test,is_binary,_,[Src]}=I, Ts) -> + case tdb_find(Src, Ts) of + {binary,U} when U rem 8 =:= 0 -> []; + _ -> [I] + end; +simplify_instr({test,is_bitstr,_,[Src]}=I, Ts) -> + case tdb_find(Src, Ts) of + {binary,_} -> []; + _ -> [I] + end; simplify_instr(I, _) -> [I]. simplify_select_val_int({select,select_val,R,_,L0}=I, {Min,Max}) -> @@ -492,8 +507,12 @@ update({test,is_eq_exact,_,[Reg,{atom,_}=Atom]}, Ts) -> update({test,is_record,_Fail,[Src,Tag,{integer,Arity}]}, Ts) -> tdb_update([{Src,{tuple,exact_size,Arity,[Tag]}}], Ts); -%% Binary matching +%% Binaries and binary matching. +update({test,is_binary,_Fail,[Src]}, Ts0) -> + tdb_update([{Src,{binary,8}}], Ts0); +update({test,is_bitstr,_Fail,[Src]}, Ts0) -> + tdb_update([{Src,{binary,1}}], Ts0); update({test,bs_get_integer2,_,_,Args,Dst}, Ts) -> tdb_update([{Dst,get_bs_integer_type(Args)}], Ts); update({test,bs_get_utf8,_,_,_,Dst}, Ts) -> @@ -502,8 +521,10 @@ update({test,bs_get_utf16,_,_,_,Dst}, Ts) -> tdb_update([{Dst,?UNICODE_INT}], Ts); update({test,bs_get_utf32,_,_,_,Dst}, Ts) -> tdb_update([{Dst,?UNICODE_INT}], Ts); +update({bs_init,_,{bs_init2,_,_},_,_,Dst}, Ts) -> + tdb_update([{Dst,{binary,8}}], Ts); update({bs_init,_,_,_,_,Dst}, Ts) -> - tdb_update([{Dst,kill}], Ts); + tdb_update([{Dst,{binary,1}}], Ts); update({bs_put,_,_,_}, Ts) -> Ts; update({bs_save2,_,_}, Ts) -> @@ -512,12 +533,19 @@ update({bs_restore2,_,_}, Ts) -> Ts; update({bs_context_to_binary,Dst}, Ts) -> tdb_update([{Dst,kill}], Ts); -update({test,bs_start_match2,_,_,_,Dst}, Ts) -> - tdb_update([{Dst,kill}], Ts); -update({test,bs_get_binary2,_,_,_,Dst}, Ts) -> - tdb_update([{Dst,kill}], Ts); +update({test,bs_start_match2,_,_,[Src,_],Dst}, Ts) -> + Type = case tdb_find(Src, Ts) of + {binary,_}=Type0 -> Type0; + _ -> {binary,1} + end, + tdb_update([{Dst,Type}], Ts); +update({test,bs_get_binary2,_,_,[_,_,Unit,_],Dst}, Ts) -> + true = is_integer(Unit), %Assertion. + tdb_update([{Dst,{binary,Unit}}], Ts); update({test,bs_get_float2,_,_,_,Dst}, Ts) -> tdb_update([{Dst,float}], Ts); +update({test,bs_test_unit,_,[Src,Unit]}, Ts) -> + tdb_update([{Src,{binary,Unit}}], Ts); update({test,_Test,_Fail,_Other}, Ts) -> Ts; @@ -554,6 +582,7 @@ update({call_fun, _}, Ts) -> tdb_kill_xregs(Ts); update({apply, _}, Ts) -> tdb_kill_xregs(Ts); update({line,_}, Ts) -> Ts; +update({'%',_}, Ts) -> Ts; %% The instruction is unknown. Kill all information. update(_I, _Ts) -> tdb_new(). @@ -792,6 +821,9 @@ checkerror_2(OrigIs) -> [{set,[],[],fcheckerror}|OrigIs]. %%% %%% 'integer' or {integer,{Min,Max}} that the register contains an %%% integer. +%%% +%%% {binary,Unit} means that the register contains a binary/bitstring aligned +%%% to unit Unit. %% tdb_new() -> EmptyDataBase %% Creates a new, empty type database. @@ -917,11 +949,14 @@ merge_type_info({integer,_}=Int, integer) -> Int; merge_type_info({integer,{Min1,Max1}}, {integer,{Min2,Max2}}) -> {integer,{max(Min1, Min2),min(Max1, Max2)}}; +merge_type_info({binary,U1}, {binary,U2}) -> + {binary,max(U1, U2)}; merge_type_info(NewType, _) -> verify_type(NewType), NewType. verify_type({atom,_}) -> ok; +verify_type({binary,U}) when is_integer(U) -> ok; verify_type(boolean) -> ok; verify_type(integer) -> ok; verify_type({integer,{Min,Max}}) diff --git a/lib/compiler/test/beam_type_SUITE.erl b/lib/compiler/test/beam_type_SUITE.erl index fe856b12b6..dfbf2aa4a0 100644 --- a/lib/compiler/test/beam_type_SUITE.erl +++ b/lib/compiler/test/beam_type_SUITE.erl @@ -23,7 +23,7 @@ init_per_group/2,end_per_group/2, integers/1,coverage/1,booleans/1,setelement/1,cons/1, tuple/1,record_float/1,binary_float/1,float_compare/1, - arity_checks/1]). + arity_checks/1,elixir_binaries/1]). suite() -> [{ct_hooks,[ts_install_cth]}]. @@ -42,7 +42,8 @@ groups() -> record_float, binary_float, float_compare, - arity_checks + arity_checks, + elixir_binaries ]}]. init_per_suite(Config) -> @@ -199,5 +200,42 @@ do_tuple_arity_check(RGB) when is_tuple(RGB), _ -> ok end. +elixir_binaries(_Config) -> + <<"foo blitzky baz">> = elixir_binary_1(<<"blitzky">>), + <<"foo * baz">> = elixir_binary_2($*), + <<7:4,755:10>> = elixir_bitstring_3(<<755:10>>), + ok. + +elixir_binary_1(Bar) when is_binary(Bar) -> + <<"foo ", + case Bar of + Rewrite when is_binary(Rewrite) -> + Rewrite; + Rewrite -> + list_to_binary(Rewrite) + end/binary, + " baz">>. + +elixir_binary_2(Arg) -> + Bin = <>, + <<"foo ", + case Bin of + Rewrite when is_binary(Rewrite) -> + Rewrite; + Rewrite -> + list_to_binary:to_string(Rewrite) + end/binary, + " baz">>. + +elixir_bitstring_3(Bar) when is_bitstring(Bar) -> + <<7:4, + case Bar of + Rewrite when is_bitstring(Rewrite) -> + Rewrite; + Rewrite -> + list_to_bitstring(Rewrite) + end/bitstring>>. + + id(I) -> I. -- cgit v1.2.3