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-rw-r--r--lib/compiler/src/beam_block.erl97
1 files changed, 59 insertions, 38 deletions
diff --git a/lib/compiler/src/beam_block.erl b/lib/compiler/src/beam_block.erl
index fe1ce6f60b..39ae8d5347 100644
--- a/lib/compiler/src/beam_block.erl
+++ b/lib/compiler/src/beam_block.erl
@@ -23,25 +23,32 @@
-module(beam_block).
-export([module/2]).
--import(lists, [reverse/1,reverse/2,foldl/3,member/2]).
+-import(lists, [reverse/1,reverse/2,member/2]).
-spec module(beam_utils:module_code(), [compile:option()]) ->
{'ok',beam_utils:module_code()}.
-module({Mod,Exp,Attr,Fs0,Lc}, _Opt) ->
- Fs = [function(F) || F <- Fs0],
+module({Mod,Exp,Attr,Fs0,Lc}, Opts) ->
+ Blockify = not member(no_blockify, Opts),
+ Fs = [function(F, Blockify) || F <- Fs0],
{ok,{Mod,Exp,Attr,Fs,Lc}}.
-function({function,Name,Arity,CLabel,Is0}) ->
+function({function,Name,Arity,CLabel,Is0}, Blockify) ->
try
%% Collect basic blocks and optimize them.
- Is1 = blockify(Is0),
- Is2 = embed_lines(Is1),
+ Is2 = case Blockify of
+ true ->
+ Is1 = blockify(Is0),
+ embed_lines(Is1);
+ false ->
+ Is0
+ end,
Is3 = beam_utils:anno_defs(Is2),
Is4 = move_allocates(Is3),
Is5 = beam_utils:live_opt(Is4),
Is6 = opt_blocks(Is5),
- Is = beam_utils:delete_live_annos(Is6),
+ Is7 = beam_utils:delete_annos(Is6),
+ Is = opt_allocs(Is7),
%% Done.
{function,Name,Arity,CLabel,Is}
@@ -136,17 +143,16 @@ embed_lines([], Acc) -> Acc.
opt_blocks([{block,Bl0}|Is]) ->
%% The live annotation at the beginning is not useful.
- [{'%live',_,_}|Bl] = Bl0,
+ [{'%anno',_}|Bl] = Bl0,
[{block,opt_block(Bl)}|opt_blocks(Is)];
opt_blocks([I|Is]) ->
[I|opt_blocks(Is)];
opt_blocks([]) -> [].
opt_block(Is0) ->
- Is = find_fixpoint(fun(Is) ->
- opt_tuple_element(opt(Is))
- end, Is0),
- opt_alloc(Is).
+ find_fixpoint(fun(Is) ->
+ opt_tuple_element(opt(Is))
+ end, Is0).
find_fixpoint(OptFun, Is0) ->
case OptFun(Is0) of
@@ -196,7 +202,7 @@ move_allocates([I|Is]) ->
[I|move_allocates(Is)];
move_allocates([]) -> [].
-move_allocates_1([{'%def',_}|Is], Acc) ->
+move_allocates_1([{'%anno',_}|Is], Acc) ->
move_allocates_1(Is, Acc);
move_allocates_1([I|Is], [{set,[],[],{alloc,Live0,Info}}|Acc]=Acc0) ->
case alloc_may_pass(I) of
@@ -240,10 +246,14 @@ opt([{set,_,_,{line,_}}=Line1,
{set,[D2],[{integer,Idx2},Reg],{bif,element,{f,0}}}=I2|Is])
when Idx1 < Idx2, D1 =/= D2, D1 =/= Reg, D2 =/= Reg ->
opt([Line2,I2,Line1,I1|Is]);
+opt([{set,[D1],[{integer,Idx1},Reg],{bif,element,{f,L}}}=I1,
+ {set,[D2],[{integer,Idx2},Reg],{bif,element,{f,L}}}=I2|Is])
+ when Idx1 < Idx2, D1 =/= D2, D1 =/= Reg, D2 =/= Reg ->
+ opt([I2,I1|Is]);
opt([{set,Ds0,Ss,Op}|Is0]) ->
{Ds,Is} = opt_moves(Ds0, Is0),
[{set,Ds,Ss,Op}|opt(Is)];
-opt([{'%live',_,_}=I|Is]) ->
+opt([{'%anno',_}=I|Is]) ->
[I|opt(Is)];
opt([]) -> [].
@@ -411,31 +421,47 @@ eliminate_use_of_from_reg([I]=Is, From, _To, Acc) ->
no
end.
+%% opt_allocs(Instructions) -> Instructions. Optimize allocate
+%% instructions inside blocks. If safe, replace an allocate_zero
+%% instruction with the slightly cheaper allocate instruction.
+
+opt_allocs(Is) ->
+ D = beam_utils:index_labels(Is),
+ opt_allocs_1(Is, D).
+
+opt_allocs_1([{block,Bl0}|Is], D) ->
+ Bl = opt_alloc(Bl0, {D,Is}),
+ [{block,Bl}|opt_allocs_1(Is, D)];
+opt_allocs_1([I|Is], D) ->
+ [I|opt_allocs_1(Is, D)];
+opt_allocs_1([], _) -> [].
+
%% opt_alloc(Instructions) -> Instructions'
%% Optimises all allocate instructions.
opt_alloc([{set,[],[],{alloc,Live0,Info0}},
- {set,[],[],{alloc,Live,Info}}|Is]) ->
+ {set,[],[],{alloc,Live,Info}}|Is], D) ->
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([]) -> [].
+ opt_alloc([I|Is], D);
+opt_alloc([{set,[],[],{alloc,R,{_,Ns,Nh,[]}}}|Is], D) ->
+ [{set,[],[],opt_alloc(Is, D, Ns, Nh, R)}|Is];
+opt_alloc([I|Is], D) -> [I|opt_alloc(Is, D)];
+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
%% allocating and initalizing the stack frame and needed heap.
-opt_alloc(_Is, nostack, Nh, LivingRegs) ->
+opt_alloc(_Is, _D, nostack, Nh, LivingRegs) ->
{alloc,LivingRegs,{nozero,nostack,Nh,[]}};
-opt_alloc(Is, Ns, Nh, LivingRegs) ->
- InitRegs = init_yreg(Is, 0),
+opt_alloc(Bl, {D,OuterIs}, Ns, Nh, LivingRegs) ->
+ Is = [{block,Bl}|OuterIs],
+ InitRegs = init_yregs(Ns, Is, D),
case count_ones(InitRegs) of
N when N*2 > Ns ->
{alloc,LivingRegs,{nozero,Ns,Nh,gen_init(Ns, InitRegs)}};
@@ -451,19 +477,14 @@ gen_init(Fs, Regs, Y, Acc) when Regs band 1 =:= 0 ->
gen_init(Fs, Regs, Y, Acc) ->
gen_init(Fs, Regs bsr 1, Y+1, Acc).
-%% init_yreg(Instructions, RegSet) -> RegSetInitialized
-%% Calculate the set of initialized y registers.
-
-init_yreg([{set,_,_,{bif,_,_}}|_], Reg) -> Reg;
-init_yreg([{set,_,_,{alloc,_,{gc_bif,_,_}}}|_], Reg) -> Reg;
-init_yreg([{set,_,_,{alloc,_,{put_map,_,_}}}|_], Reg) -> Reg;
-init_yreg([{set,Ds,_,_}|Is], Reg) -> init_yreg(Is, add_yregs(Ds, Reg));
-init_yreg(_Is, Reg) -> Reg.
-
-add_yregs(Ys, Reg) -> foldl(fun(Y, R0) -> add_yreg(Y, R0) end, Reg, Ys).
-
-add_yreg({y,Y}, Reg) -> Reg bor (1 bsl Y);
-add_yreg(_, Reg) -> Reg.
+init_yregs(Y, Is, D) when Y >= 0 ->
+ case beam_utils:is_killed({y,Y}, Is, D) of
+ true ->
+ (1 bsl Y) bor init_yregs(Y-1, Is, D);
+ false ->
+ init_yregs(Y-1, Is, D)
+ end;
+init_yregs(_, _, _) -> 0.
count_ones(Bits) -> count_ones(Bits, 0).
count_ones(0, Acc) -> Acc;
@@ -514,7 +535,7 @@ x_live([], Regs) -> Regs.
%% Given a reversed instruction stream, determine the
%% the registers that are defined.
-defined_regs([{'%def',Def}|_], Regs) ->
+defined_regs([{'%anno',{def,Def}}|_], Regs) ->
Def bor Regs;
defined_regs([{set,Ds,_,{alloc,Live,_}}|_], Regs) ->
x_live(Ds, Regs bor ((1 bsl Live) - 1));