File 2452-Explicit-pass-RPO-to-beam_ssa-functions-cont.patch of Package erlang
From 35f10baeda472d82f568be6802bd4abda8da4195 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jos=C3=A9=20Valim?= <jose.valim@dashbit.co>
Date: Tue, 3 Nov 2020 12:21:50 +0100
Subject: [PATCH] Explicit pass RPO to beam_ssa functions (cont)
This patch finishes the work started on 0ce3fb91
by explicitly passing RPO to the remaining functions
in beam_ssa. This commit avoids the double RPO
computation in 5 other occasions.
---
lib/compiler/src/beam_ssa.erl | 48 +++++++++++------------
lib/compiler/src/beam_ssa_bool.erl | 4 +-
lib/compiler/src/beam_ssa_bsm.erl | 10 +++--
lib/compiler/src/beam_ssa_opt.erl | 6 ++-
lib/compiler/src/beam_ssa_pre_codegen.erl | 41 +++++++++++--------
5 files changed, 59 insertions(+), 50 deletions(-)
diff --git a/lib/compiler/src/beam_ssa.erl b/lib/compiler/src/beam_ssa.erl
index d5fe4b7d9c..76303b34cb 100644
--- a/lib/compiler/src/beam_ssa.erl
+++ b/lib/compiler/src/beam_ssa.erl
@@ -23,7 +23,7 @@
-export([add_anno/3,get_anno/2,get_anno/3,
between/4,
clobbers_xregs/1,def/2,def_unused/3,
- definitions/1,
+ definitions/2,
dominators/2,dominators_from_predecessors/2,common_dominators/3,
flatmapfold_instrs/4,
fold_blocks/4,
@@ -32,13 +32,13 @@
linearize/1,
mapfold_blocks/4,
mapfold_instrs/4,
- merge_blocks/1,
+ merge_blocks/2,
normalize/1,
no_side_effect/1,
predecessors/1,
rename_vars/3,
rpo/1,rpo/2,
- split_blocks/3,
+ split_blocks/4,
successors/1,successors/2,
trim_unreachable/1,
used/1,uses/2]).
@@ -344,8 +344,7 @@ successors(L, Blocks) ->
Def :: ordsets:ordset(var_name()).
def(Ls, Blocks) ->
- Top = rpo(Ls, Blocks),
- Blks = [map_get(L, Blocks) || L <- Top],
+ Blks = [map_get(L, Blocks) || L <- Ls],
def_1(Blks, []).
-spec def_unused(Ls, Used, Blocks) -> {Def,Unused} when
@@ -356,9 +355,8 @@ def(Ls, Blocks) ->
Unused :: ordsets:ordset(var_name()).
def_unused(Ls, Unused, Blocks) ->
- Top = rpo(Ls, Blocks),
- Blks = [map_get(L, Blocks) || L <- Top],
- Preds = cerl_sets:from_list(Top),
+ Blks = [map_get(L, Blocks) || L <- Ls],
+ Preds = cerl_sets:from_list(Ls),
def_unused_1(Blks, Preds, [], Unused).
%% dominators(Labels, BlockMap) -> {Dominators,Numbering}.
@@ -533,11 +531,10 @@ between(From, To, Preds, Blocks) ->
-spec rename_vars(Rename, [label()], block_map()) -> block_map() when
Rename :: rename_map() | rename_proplist().
-rename_vars(Rename, From, Blocks) when is_list(Rename) ->
- rename_vars(maps:from_list(Rename), From, Blocks);
-rename_vars(Rename, From, Blocks) when is_map(Rename)->
- Top = rpo(From, Blocks),
- Preds = cerl_sets:from_list(Top),
+rename_vars(Rename, Labels, Blocks) when is_list(Rename) ->
+ rename_vars(maps:from_list(Rename), Labels, Blocks);
+rename_vars(Rename, Labels, Blocks) when is_map(Rename)->
+ Preds = cerl_sets:from_list(Labels),
F = fun(#b_set{op=phi,args=Args0}=Set) ->
Args = rename_phi_vars(Args0, Preds, Rename),
normalize(Set#b_set{args=Args});
@@ -551,23 +548,23 @@ rename_vars(Rename, From, Blocks) when is_map(Rename)->
(#b_ret{arg=Arg}=Ret) ->
normalize(Ret#b_ret{arg=rename_var(Arg, Rename)})
end,
- map_instrs_1(Top, F, Blocks).
+ map_instrs_1(Labels, F, Blocks).
%% split_blocks(Predicate, Blocks0, Count0) -> {Blocks,Count}.
%% Call Predicate(Instruction) for each instruction in all
%% blocks. If Predicate/1 returns true, split the block
%% before this instruction.
--spec split_blocks(Pred, Blocks0, Count0) -> {Blocks,Count} when
+-spec split_blocks(Labels, Pred, Blocks0, Count0) -> {Blocks,Count} when
+ Labels :: [label()],
Pred :: fun((b_set()) -> boolean()),
Blocks :: block_map(),
- Count0 :: beam_ssa:label(),
+ Count0 :: label(),
Blocks0 :: block_map(),
Blocks :: block_map(),
- Count :: beam_ssa:label().
+ Count :: label().
-split_blocks(P, Blocks, Count) ->
- Ls = rpo(Blocks),
+split_blocks(Ls, P, Blocks, Count) ->
split_blocks_1(Ls, P, Blocks, Count).
-spec trim_unreachable(SSA0) -> SSA when
@@ -601,14 +598,13 @@ used(#b_switch{arg=#b_var{}=V}) ->
[V];
used(_) -> [].
--spec definitions(Blocks :: block_map()) -> definition_map().
-definitions(Blocks) ->
- Top = rpo(Blocks),
+-spec definitions(Labels :: [label()], Blocks :: block_map()) -> definition_map().
+definitions(Labels, Blocks) ->
fold_instrs(fun(#b_set{ dst = Var }=I, Acc) ->
Acc#{Var => I};
(_Terminator, Acc) ->
Acc
- end, Top, #{}, Blocks).
+ end, Labels, #{}, Blocks).
%% uses(Labels, BlockMap) -> UsageMap
%% Traverse the blocks given by labels and builds a usage map
@@ -630,15 +626,15 @@ fold_uses_block(Lbl, #b_blk{is=Is,last=Last}, UseMap0) ->
end,
F(Last, foldl(F, UseMap0, Is)).
--spec merge_blocks(block_map()) -> block_map().
+-spec merge_blocks([label()], block_map()) -> block_map().
-merge_blocks(Blocks) ->
+merge_blocks(Labels, Blocks) ->
Preds = predecessors(Blocks),
%% We must traverse the blocks in reverse postorder to avoid
%% embedding succeeded:guard instructions into the middle of
%% blocks when this function is called from beam_ssa_bool.
- merge_blocks_1(rpo(Blocks), Preds, Blocks).
+ merge_blocks_1(Labels, Preds, Blocks).
%%%
%%% Internal functions.
diff --git a/lib/compiler/src/beam_ssa_bool.erl b/lib/compiler/src/beam_ssa_bool.erl
index 5fa60c3b19..b3b41e68c3 100644
--- a/lib/compiler/src/beam_ssa_bool.erl
+++ b/lib/compiler/src/beam_ssa_bool.erl
@@ -160,7 +160,7 @@ opt_function(#b_function{bs=Blocks0,cnt=Count0}=F) ->
%% To ensure that, trim before merging.
Blocks3 = beam_ssa:trim_unreachable(Blocks2),
- Blocks = beam_ssa:merge_blocks(Blocks3),
+ Blocks = beam_ssa:merge_blocks(beam_ssa:rpo(Blocks3), Blocks3),
F#b_function{bs=Blocks,cnt=Count};
true ->
%% There are no boolean operators that can be optimized in
@@ -1504,7 +1504,7 @@ join_inits_1([], VarMap) ->
%%%
%%% We don't try merge blocks during the conversion because it would
%%% be difficult to keep phi nodes up to date. We will call
-%%% beam_ssa:merge_blocks/1 before returning from this pass to do all
+%%% beam_ssa:merge_blocks/2 before returning from this pass to do all
%%% block merging.
%%%
diff --git a/lib/compiler/src/beam_ssa_bsm.erl b/lib/compiler/src/beam_ssa_bsm.erl
index 9984c3586f..59872290a6 100644
--- a/lib/compiler/src/beam_ssa_bsm.erl
+++ b/lib/compiler/src/beam_ssa_bsm.erl
@@ -459,12 +459,14 @@ combine_matches(#b_function{bs=Blocks0,cnt=Counter0}=F, ModInfo) ->
{Block0#b_blk{is=Is}, State}
end,
RPO,
- #cm{ definitions = beam_ssa:definitions(Blocks0),
+ #cm{ definitions = beam_ssa:definitions(RPO, Blocks0),
dominators = Dominators,
blocks = Blocks0 },
Blocks0),
- Blocks2 = beam_ssa:rename_vars(State#cm.renames, [0], Blocks1),
+ %% The fun in mapfold_blocks does not update terminators,
+ %% so we can reuse the RPO computed for Blocks0.
+ Blocks2 = beam_ssa:rename_vars(State#cm.renames, RPO, Blocks1),
{Blocks, Counter} = alias_matched_binaries(Blocks2, Counter0,
State#cm.match_aliases),
@@ -852,10 +854,10 @@ skip_outgoing_tail_extraction({Fs0, ModInfo}) ->
skip_outgoing_tail_extraction(#b_function{bs=Blocks0}=F, ModInfo) ->
case funcinfo_get(F, has_bsm_ops, ModInfo) of
true ->
- State0 = #sote{ definitions = beam_ssa:definitions(Blocks0),
+ RPO = beam_ssa:rpo(Blocks0),
+ State0 = #sote{ definitions = beam_ssa:definitions(RPO, Blocks0),
mod_info = ModInfo },
- RPO = beam_ssa:rpo(Blocks0),
{Blocks1, State} = beam_ssa:mapfold_instrs(
fun sote_rewrite_calls/2, RPO, State0, Blocks0),
diff --git a/lib/compiler/src/beam_ssa_opt.erl b/lib/compiler/src/beam_ssa_opt.erl
index e08f60d7b3..3cd25ff273 100644
--- a/lib/compiler/src/beam_ssa_opt.erl
+++ b/lib/compiler/src/beam_ssa_opt.erl
@@ -453,7 +453,8 @@ ssa_opt_trim_unreachable({#opt_st{ssa=Blocks}=St, FuncDb}) ->
{St#opt_st{ssa=beam_ssa:trim_unreachable(Blocks)}, FuncDb}.
ssa_opt_merge_blocks({#opt_st{ssa=Blocks0}=St, FuncDb}) ->
- Blocks = beam_ssa:merge_blocks(Blocks0),
+ RPO = beam_ssa:rpo(Blocks0),
+ Blocks = beam_ssa:merge_blocks(RPO, Blocks0),
{St#opt_st{ssa=Blocks}, FuncDb}.
%%%
@@ -472,7 +473,8 @@ ssa_opt_split_blocks({#opt_st{ssa=Blocks0,cnt=Count0}=St, FuncDb}) ->
(#b_set{op=make_fun}) -> true;
(_) -> false
end,
- {Blocks,Count} = beam_ssa:split_blocks(P, Blocks0, Count0),
+ RPO = beam_ssa:rpo(Blocks0),
+ {Blocks,Count} = beam_ssa:split_blocks(RPO, P, Blocks0, Count0),
{St#opt_st{ssa=Blocks,cnt=Count}, FuncDb}.
%%%
diff --git a/lib/compiler/src/beam_ssa_pre_codegen.erl b/lib/compiler/src/beam_ssa_pre_codegen.erl
index 57fbc33558..78f9571e46 100644
--- a/lib/compiler/src/beam_ssa_pre_codegen.erl
+++ b/lib/compiler/src/beam_ssa_pre_codegen.erl
@@ -750,7 +750,8 @@ sanitize([], Count, Blocks0, Values) ->
map_size(Values) =:= 0 ->
Blocks0;
true ->
- beam_ssa:rename_vars(Values, [0], Blocks0)
+ RPO = beam_ssa:rpo(Blocks0),
+ beam_ssa:rename_vars(Values, RPO, Blocks0)
end,
%% Unreachable blocks can cause problems for the dominator calculations.
@@ -1511,7 +1512,8 @@ fix_receives_1([{L,Blk}|Ls], Blocks0, Count0) ->
#b_blk{is=[#b_set{op=peek_message}|_]} ->
Rm = find_rm_blocks(L, Blocks0),
LoopExit = find_loop_exit(Rm, Blocks0),
- Defs0 = beam_ssa:def([L], Blocks0),
+ RPO = beam_ssa:rpo([L], Blocks0),
+ Defs0 = beam_ssa:def(RPO, Blocks0),
CommonUsed = recv_common(Defs0, LoopExit, Blocks0),
{Blocks1,Count1} = recv_crit_edges(Rm, LoopExit, Blocks0, Count0),
{Blocks2,Count2} = recv_fix_common(CommonUsed, LoopExit, Rm,
@@ -1530,7 +1532,8 @@ recv_common(_Defs, none, _Blocks) ->
%% in the tail position of a function.
[];
recv_common(Defs, Exit, Blocks) ->
- {ExitDefs,ExitUnused} = beam_ssa:def_unused([Exit], Defs, Blocks),
+ RPO = beam_ssa:rpo([Exit], Blocks),
+ {ExitDefs,ExitUnused} = beam_ssa:def_unused(RPO, Defs, Blocks),
Def = ordsets:subtract(Defs, ExitDefs),
ordsets:subtract(Def, ExitUnused).
@@ -1592,7 +1595,8 @@ rce_reroute_terminator(#b_switch{list=List0}=Last, Exit, New) ->
recv_fix_common([Msg0|T], Exit, Rm, Blocks0, Count0) ->
{Msg,Count1} = new_var('@recv', Count0),
- Blocks1 = beam_ssa:rename_vars(#{Msg0=>Msg}, [Exit], Blocks0),
+ RPO = beam_ssa:rpo([Exit], Blocks0),
+ Blocks1 = beam_ssa:rename_vars(#{Msg0=>Msg}, RPO, Blocks0),
N = length(Rm),
{MsgVars,Count} = new_vars(duplicate(N, '@recv'), Count1),
PhiArgs = fix_exit_phi_args(MsgVars, Rm, Exit, Blocks1),
@@ -1607,7 +1611,8 @@ recv_fix_common([], _, _, Blocks, Count) ->
recv_fix_common_1([V|Vs], [Rm|Rms], Msg, Blocks0) ->
Ren = #{Msg=>V},
- Blocks1 = beam_ssa:rename_vars(Ren, [Rm], Blocks0),
+ RPO = beam_ssa:rpo([Rm], Blocks0),
+ Blocks1 = beam_ssa:rename_vars(Ren, RPO, Blocks0),
#b_blk{is=Is0} = Blk0 = map_get(Rm, Blocks1),
Copy = #b_set{op=copy,dst=V,args=[Msg]},
Is = insert_after_phis(Is0, [Copy]),
@@ -1637,12 +1642,13 @@ exit_predecessors([], _Exit, _Blocks) -> [].
%% later used within a clause of the receive.
fix_receive([L|Ls], Defs, Blocks0, Count0) ->
- {RmDefs,Unused} = beam_ssa:def_unused([L], Defs, Blocks0),
+ RPO = beam_ssa:rpo([L], Blocks0),
+ {RmDefs,Unused} = beam_ssa:def_unused(RPO, Defs, Blocks0),
Def = ordsets:subtract(Defs, RmDefs),
Used = ordsets:subtract(Def, Unused),
{NewVars,Count} = new_vars([Base || #b_var{name=Base} <- Used], Count0),
Ren = zip(Used, NewVars),
- Blocks1 = beam_ssa:rename_vars(Ren, [L], Blocks0),
+ Blocks1 = beam_ssa:rename_vars(Ren, RPO, Blocks0),
#b_blk{is=Is0} = Blk1 = map_get(L, Blocks1),
CopyIs = [#b_set{op=copy,dst=New,args=[Old]} || {Old,New} <- Ren],
Is = insert_after_phis(Is0, CopyIs),
@@ -1667,8 +1673,8 @@ find_loop_exit([_,_|_]=RmBlocks, Blocks) ->
RPO = beam_ssa:rpo(Blocks),
{Dominators,_} = beam_ssa:dominators(RPO, Blocks),
RmSet = cerl_sets:from_list(RmBlocks),
- Rpo = beam_ssa:rpo(RmBlocks, Blocks),
- find_loop_exit_1(Rpo, RmSet, Dominators, Blocks);
+ RmRPO = beam_ssa:rpo(RmBlocks, Blocks),
+ find_loop_exit_1(RmRPO, RmSet, Dominators, Blocks);
find_loop_exit(_, _) ->
%% There is (at most) a single clause. There is no common
%% loop exit block.
@@ -2342,10 +2348,11 @@ reserve_yregs(#st{frames=Frames}=St0) ->
reserve_yregs_1(L, #st{ssa=Blocks0,cnt=Count0,res=Res0}=St) ->
Blk = map_get(L, Blocks0),
Yregs = ordsets:from_list(cerl_sets:to_list(beam_ssa:get_anno(yregs, Blk))),
- {Def,Unused} = beam_ssa:def_unused([L], Yregs, Blocks0),
+ RPO = beam_ssa:rpo([L], Blocks0),
+ {Def,Unused} = beam_ssa:def_unused(RPO, Yregs, Blocks0),
UsedYregs = ordsets:subtract(Yregs, Unused),
DefBefore = ordsets:subtract(UsedYregs, Def),
- {BeforeVars,Blocks,Count} = rename_vars(DefBefore, L, Blocks0, Count0),
+ {BeforeVars,Blocks,Count} = rename_vars(DefBefore, L, RPO, Blocks0, Count0),
InsideVars = ordsets:subtract(UsedYregs, DefBefore),
ResTryTags0 = reserve_try_tags(L, Blocks),
ResTryTags = [{V,{Reg,Count}} || {V,Reg} <- ResTryTags0],
@@ -2403,12 +2410,12 @@ update_act_map([L|Ls], Active0, ActMap0) ->
end;
update_act_map([], _, ActMap) -> ActMap.
-rename_vars([], _, Blocks, Count) ->
+rename_vars([], _, _, Blocks, Count) ->
{[],Blocks,Count};
-rename_vars(Vs, L, Blocks0, Count0) ->
+rename_vars(Vs, L, RPO, Blocks0, Count0) ->
{NewVars,Count} = new_vars([Base || #b_var{name=Base} <- Vs], Count0),
Ren = zip(Vs, NewVars),
- Blocks1 = beam_ssa:rename_vars(Ren, [L], Blocks0),
+ Blocks1 = beam_ssa:rename_vars(Ren, RPO, Blocks0),
#b_blk{is=Is0} = Blk0 = map_get(L, Blocks1),
CopyIs = [#b_set{op=copy,dst=New,args=[Old]} || {Old,New} <- Ren],
Is = insert_after_phis(Is0, CopyIs),
@@ -2434,7 +2441,8 @@ frame_size(#st{frames=Frames,regs=Regs,ssa=Blocks0}=St) ->
St#st{ssa=Blocks}.
frame_size_1(L, Regs, Blocks0) ->
- Def = beam_ssa:def([L], Blocks0),
+ RPO = beam_ssa:rpo([L], Blocks0),
+ Def = beam_ssa:def(RPO, Blocks0),
Yregs0 = [map_get(V, Regs) || V <- Def, is_yreg(map_get(V, Regs))],
Yregs = ordsets:from_list(Yregs0),
FrameSize = length(ordsets:from_list(Yregs)),
@@ -2480,7 +2488,8 @@ turn_yregs(#st{frames=Frames,regs=Regs0,ssa=Blocks}=St) ->
Regs1 = foldl(fun(L, A) ->
Blk = map_get(L, Blocks),
FrameSize = beam_ssa:get_anno(frame_size, Blk),
- Def = beam_ssa:def([L], Blocks),
+ RPO = beam_ssa:rpo([L], Blocks),
+ Def = beam_ssa:def(RPO, Blocks),
[turn_yregs_1(Def, FrameSize, Regs0)|A]
end, [], Frames),
Regs = maps:merge(Regs0, maps:from_list(append(Regs1))),
--
2.26.2
