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-rw-r--r--lib/hipe/icode/Makefile4
-rw-r--r--lib/hipe/icode/hipe_icode.erl14
-rw-r--r--lib/hipe/icode/hipe_icode.hrl2
-rw-r--r--lib/hipe/icode/hipe_icode_call_elim.erl78
-rw-r--r--lib/hipe/icode/hipe_icode_cfg.erl3
-rw-r--r--lib/hipe/icode/hipe_icode_range.erl156
-rw-r--r--lib/hipe/icode/hipe_icode_type.erl34
7 files changed, 183 insertions, 108 deletions
diff --git a/lib/hipe/icode/Makefile b/lib/hipe/icode/Makefile
index a5edb10d90..b220bc16a0 100644
--- a/lib/hipe/icode/Makefile
+++ b/lib/hipe/icode/Makefile
@@ -59,7 +59,7 @@ DOC_MODULES = hipe_beam_to_icode \
hipe_icode_pp hipe_icode_primops \
hipe_icode_range \
hipe_icode_split_arith \
- hipe_icode_ssa hipe_icode_ssa_const_prop \
+ hipe_icode_ssa hipe_icode_ssa_const_prop hipe_icode_call_elim \
hipe_icode_ssa_copy_prop hipe_icode_ssa_struct_reuse \
hipe_icode_type $(HIPE_MODULES)
@@ -84,7 +84,7 @@ DOC_FILES= $(DOC_MODULES:%=$(DOCS)/%.html)
include ../native.mk
-ERL_COMPILE_FLAGS += +warn_unused_import +warn_exported_vars +warn_missing_spec # +warn_untyped_record
+ERL_COMPILE_FLAGS += -Werror +warn_unused_import +warn_export_vars +warn_missing_spec # +warn_untyped_record
# ----------------------------------------------------
# Targets
diff --git a/lib/hipe/icode/hipe_icode.erl b/lib/hipe/icode/hipe_icode.erl
index 07d230491d..78508dff22 100644
--- a/lib/hipe/icode/hipe_icode.erl
+++ b/lib/hipe/icode/hipe_icode.erl
@@ -610,7 +610,9 @@
%% Exported types
%%
--export_type([icode/0]).
+-export_type([icode/0, params/0]).
+
+-type params() :: [icode_var()].
%%---------------------------------------------------------------------
%%
@@ -618,7 +620,7 @@
%%
%%---------------------------------------------------------------------
--spec mk_icode(mfa(), [icode_var()], boolean(), boolean(), [icode_instr()],
+-spec mk_icode(mfa(), params(), boolean(), boolean(), [icode_instr()],
{non_neg_integer(),non_neg_integer()},
{icode_lbl(),icode_lbl()}) -> icode().
mk_icode(Fun, Params, IsClosure, IsLeaf, Code, VarRange, LabelRange) ->
@@ -629,7 +631,7 @@ mk_icode(Fun, Params, IsClosure, IsLeaf, Code, VarRange, LabelRange) ->
var_range=VarRange,
label_range=LabelRange}.
--spec mk_icode(mfa(), [icode_var()], boolean(), boolean(), [icode_instr()],
+-spec mk_icode(mfa(), params(), boolean(), boolean(), [icode_instr()],
hipe_consttab(), {non_neg_integer(),non_neg_integer()},
{icode_lbl(),icode_lbl()}) -> icode().
mk_icode(Fun, Params, IsClosure, IsLeaf, Code, Data, VarRange, LabelRange) ->
@@ -640,11 +642,11 @@ mk_icode(Fun, Params, IsClosure, IsLeaf, Code, Data, VarRange, LabelRange) ->
-spec icode_fun(icode()) -> mfa().
icode_fun(#icode{'fun' = MFA}) -> MFA.
--spec icode_params(icode()) -> [icode_var()].
+-spec icode_params(icode()) -> params().
icode_params(#icode{params = Params}) -> Params.
--spec icode_params_update(icode(), [icode_var()]) -> icode().
-icode_params_update(Icode, Params) ->
+-spec icode_params_update(icode(), params()) -> icode().
+icode_params_update(Icode, Params) ->
Icode#icode{params = Params}.
-spec icode_is_closure(icode()) -> boolean().
diff --git a/lib/hipe/icode/hipe_icode.hrl b/lib/hipe/icode/hipe_icode.hrl
index 999c54732b..b2e0d86b28 100644
--- a/lib/hipe/icode/hipe_icode.hrl
+++ b/lib/hipe/icode/hipe_icode.hrl
@@ -169,7 +169,7 @@
%%---------------------------------------------------------------------
-record(icode, {'fun' :: mfa(),
- params :: [icode_var()],
+ params :: hipe_icode:params(),
%% TODO: merge is_closure and closure_arity into one field
is_closure :: boolean(),
closure_arity = none :: 'none' | arity(),
diff --git a/lib/hipe/icode/hipe_icode_call_elim.erl b/lib/hipe/icode/hipe_icode_call_elim.erl
new file mode 100644
index 0000000000..6a22133962
--- /dev/null
+++ b/lib/hipe/icode/hipe_icode_call_elim.erl
@@ -0,0 +1,78 @@
+%% -*- erlang-indent-level: 2 -*-
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2016. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%% http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+%%----------------------------------------------------------------------
+%% File : hipe_icode_call_elim.erl
+%% Authors : Daniel S. McCain <[email protected]>,
+%% Magnus Lång <[email protected]>
+%% Created : 14 Apr 2014 by Magnus Lång <[email protected]>
+%% Purpose : Eliminate calls to BIFs that are side-effect free only when
+%% executed on some argument types.
+%%----------------------------------------------------------------------
+-module(hipe_icode_call_elim).
+-export([cfg/1]).
+
+-include("hipe_icode.hrl").
+-include("../flow/cfg.hrl").
+
+-spec cfg(cfg()) -> cfg().
+
+cfg(IcodeSSA) ->
+ lists:foldl(fun (Lbl, CFG1) ->
+ BB1 = hipe_icode_cfg:bb(CFG1, Lbl),
+ Code1 = hipe_bb:code(BB1),
+ Code2 = lists:map(fun elim_insn/1, Code1),
+ BB2 = hipe_bb:code_update(BB1, Code2),
+ hipe_icode_cfg:bb_add(CFG1, Lbl, BB2)
+ end, IcodeSSA, hipe_icode_cfg:labels(IcodeSSA)).
+
+-spec elim_insn(icode_instr()) -> icode_instr().
+elim_insn(Insn=#icode_call{'fun'={_,_,_}=MFA, args=Args, type=remote,
+ dstlist=[Dst=#icode_variable{
+ annotation={type_anno, RetType, _}}]}) ->
+ Opaques = 'universe',
+ case erl_types:t_is_singleton(RetType, Opaques) of
+ true ->
+ ArgTypes = [case Arg of
+ #icode_variable{annotation={type_anno, Type, _}} -> Type;
+ #icode_const{} ->
+ erl_types:t_from_term(hipe_icode:const_value(Arg))
+ end || Arg <- Args],
+ case can_be_eliminated(MFA, ArgTypes) of
+ true ->
+ Const = hipe_icode:mk_const(
+ erl_types:t_singleton_to_term(RetType, Opaques)),
+ #icode_move{dst=Dst, src=Const};
+ false -> Insn
+ end;
+ false -> Insn
+ end;
+elim_insn(Insn) -> Insn.
+
+
+%% A function can be eliminated for some argument types if it has no side
+%% effects when run on arguments of those types.
+
+-spec can_be_eliminated(mfa(), [erl_types:erl_type()]) -> boolean().
+
+can_be_eliminated({maps, is_key, 2}, [_K, M]) ->
+ erl_types:t_is_map(M);
+can_be_eliminated(_, _) ->
+ false.
diff --git a/lib/hipe/icode/hipe_icode_cfg.erl b/lib/hipe/icode/hipe_icode_cfg.erl
index b9969fa69d..9a602c0283 100644
--- a/lib/hipe/icode/hipe_icode_cfg.erl
+++ b/lib/hipe/icode/hipe_icode_cfg.erl
@@ -55,6 +55,9 @@
-spec postorder(cfg()) -> [icode_lbl()].
-spec reverse_postorder(cfg()) -> [icode_lbl()].
+-spec params(cfg()) -> hipe_icode:params().
+-spec params_update(cfg(), hipe_icode:params()) -> cfg().
+
-spec is_visited(icode_lbl(), gb_sets:set()) -> boolean().
-spec visit(icode_lbl(), gb_sets:set()) -> gb_sets:set().
diff --git a/lib/hipe/icode/hipe_icode_range.erl b/lib/hipe/icode/hipe_icode_range.erl
index 24ffc71237..12ed796690 100644
--- a/lib/hipe/icode/hipe_icode_range.erl
+++ b/lib/hipe/icode/hipe_icode_range.erl
@@ -89,6 +89,7 @@
ret_type :: range(),
lookup_fun :: call_fun(),
result_action :: final_fun()}).
+-type state() :: #state{}.
-define(WIDEN, 1).
@@ -172,7 +173,7 @@ analyse(Cfg, Data) ->
catch throw:no_input -> ok
end.
--spec safe_analyse(cfg(), data()) -> #state{}.
+-spec safe_analyse(cfg(), data()) -> state().
safe_analyse(CFG, Data={MFA,_,_,_}) ->
State = state__init(CFG, Data),
@@ -181,14 +182,14 @@ safe_analyse(CFG, Data={MFA,_,_,_}) ->
(state__result_action(NewState))(MFA, [state__ret_type(NewState)]),
NewState.
--spec rewrite_blocks(#state{}) -> #state{}.
+-spec rewrite_blocks(state()) -> state().
rewrite_blocks(State) ->
CFG = state__cfg(State),
Start = hipe_icode_cfg:start_label(CFG),
rewrite_blocks([Start], State, [Start]).
--spec rewrite_blocks([label()], #state{}, [label()]) -> #state{}.
+-spec rewrite_blocks([label()], state(), [label()]) -> state().
rewrite_blocks([Next|Rest], State, Visited) ->
Info = state__info_in(State, Next),
@@ -201,7 +202,7 @@ rewrite_blocks([Next|Rest], State, Visited) ->
rewrite_blocks([], State, _) ->
State.
--spec analyse_blocks(#state{}, work_list()) -> #state{}.
+-spec analyse_blocks(state(), work_list()) -> state().
analyse_blocks(State, Work) ->
case get_work(Work) of
@@ -218,7 +219,7 @@ analyse_blocks(State, Work) ->
analyse_blocks(NewState, NewWork2)
end.
--spec analyse_block(label(), info(), #state{}, boolean()) -> {#state{}, [label()]}.
+-spec analyse_block(label(), info(), state(), boolean()) -> {state(), [label()]}.
analyse_block(Label, Info, State, Rewrite) ->
BB = state__bb(State, Label),
@@ -612,36 +613,32 @@ analyse_if(If, Info, Rewrite) ->
{#icode_goto{} | #icode_if{}, [{label(), info()}]}.
analyse_sane_if(If, Info, [Arg1, Arg2], [Range1, Range2], Rewrite) ->
- case normalize_name(hipe_icode:if_op(If)) of
- '>' ->
- {TrueRange2, TrueRange1, FalseRange2, FalseRange1} =
- range_inequality_propagation(Range2, Range1);
- '<' ->
- {TrueRange1, TrueRange2, FalseRange1, FalseRange2} =
+ {TrueRange1, TrueRange2, FalseRange1, FalseRange2} =
+ case normalize_name(hipe_icode:if_op(If)) of
+ '>' ->
+ {TR2, TR1, FR2, FR1} = range_inequality_propagation(Range2, Range1),
+ {TR1, TR2, FR1, FR2};
+ '<' ->
range_inequality_propagation(Range1, Range2);
- '>=' ->
- {FalseRange1, FalseRange2, TrueRange1, TrueRange2} =
- range_inequality_propagation(Range1, Range2);
- '=<' ->
- {FalseRange2, FalseRange1, TrueRange2, TrueRange1} =
- range_inequality_propagation(Range2, Range1);
- '=:=' ->
- {TrueRange1, TrueRange2, FalseRange1, FalseRange2} =
- range_equality_propagation(Range1, Range2);
- '=/=' ->
- {FalseRange1, FalseRange2, TrueRange1, TrueRange2} =
- range_equality_propagation(Range1, Range2);
- '==' ->
- {TempTrueRange1, TempTrueRange2, FalseRange1, FalseRange2} =
- range_equality_propagation(Range1, Range2),
- TrueRange1 = set_other(TempTrueRange1, other(Range1)),
- TrueRange2 = set_other(TempTrueRange2, other(Range2));
- '/=' ->
- {TempFalseRange1, TempFalseRange2, TrueRange1, TrueRange2} =
- range_equality_propagation(Range1, Range2),
- FalseRange1 = set_other(TempFalseRange1, other(Range1)),
- FalseRange2 = set_other(TempFalseRange2, other(Range2))
- end,
+ '>=' ->
+ {FR1, FR2, TR1, TR2} = range_inequality_propagation(Range1, Range2),
+ {TR1, TR2, FR1, FR2};
+ '=<' ->
+ {FR2, FR1, TR2, TR1} = range_inequality_propagation(Range2, Range1),
+ {TR1, TR2, FR1, FR2};
+ '=:=' ->
+ {TR1, TR2, FR1, FR2} = range_equality_propagation(Range1, Range2),
+ {TR1, TR2, FR1, FR2};
+ '=/=' ->
+ {FR1, FR2, TR1, TR2} = range_equality_propagation(Range1, Range2),
+ {TR1, TR2, FR1, FR2};
+ '==' ->
+ {TR1, TR2, FR1, FR2} = range_equality_propagation(Range1, Range2),
+ {set_other(TR1,other(Range1)), set_other(TR2,other(Range2)), FR1, FR2};
+ '/=' ->
+ {FR1, FR2, TR1, TR2} = range_equality_propagation(Range1, Range2),
+ {TR1, TR2, set_other(FR1,other(Range1)), set_other(FR2,other(Range2))}
+ end,
%% io:format("TR1 = ~w\nTR2 = ~w\n", [TrueRange1, TrueRange2]),
True =
case lists:all(fun range__is_none/1, [TrueRange1, TrueRange2]) of
@@ -694,26 +691,24 @@ normalize_name(Name) ->
-spec range_equality_propagation(range(), range()) ->
{range(), range(), range(), range()}.
-range_equality_propagation(Range_1, Range_2) ->
- True_range = inf(Range_1, Range_2),
- case {range(Range_1), range(Range_2)} of
- {{N,N}, {N,N}} ->
- False_range_1 = none_range(),
- False_range_2 = none_range();
- {{N1,N1}, {N2,N2}} ->
- False_range_1 = Range_1,
- False_range_2 = Range_2;
- {{N,N}, _} ->
- False_range_1 = Range_1,
- {_,False_range_2} = compare_with_integer(N, Range_2);
- {_, {N,N}} ->
- False_range_2 = Range_2,
- {_,False_range_1} = compare_with_integer(N, Range_1);
- {_, _} ->
- False_range_1 = Range_1,
- False_range_2 = Range_2
- end,
- {True_range, True_range, False_range_1, False_range_2}.
+range_equality_propagation(Range1, Range2) ->
+ TrueRange = inf(Range1, Range2),
+ {FalseRange1, FalseRange2} =
+ case {range(Range1), range(Range2)} of
+ {{N,N}, {N,N}} ->
+ {none_range(), none_range()};
+ {{N1,N1}, {N2,N2}} ->
+ {Range1, Range2};
+ {{N,N}, _} ->
+ {_,FR2} = compare_with_integer(N, Range2),
+ {Range1, FR2};
+ {_, {N,N}} ->
+ {_,FR1} = compare_with_integer(N, Range1),
+ {FR1, Range2};
+ {_, _} ->
+ {Range1, Range2}
+ end,
+ {TrueRange, TrueRange, FalseRange1, FalseRange2}.
-spec range_inequality_propagation(range(), range()) ->
{range(), range(), range(), range()}.
@@ -779,18 +774,17 @@ analyse_type(Type, Info, Rewrite) ->
TypeTest = hipe_icode:type_test(Type),
[Arg|_] = hipe_icode:type_args(Type),
OldVarRange = get_range_from_arg(Arg),
- case TypeTest of
- {integer, N} ->
- {TrueRange,FalseRange} = compare_with_integer(N,OldVarRange);
- integer ->
- TrueRange = inf(any_range(), OldVarRange),
- FalseRange = inf(none_range(), OldVarRange);
- number ->
- TrueRange = FalseRange = OldVarRange;
- _ ->
- TrueRange = inf(none_range(), OldVarRange),
- FalseRange = OldVarRange
- end,
+ {TrueRange, FalseRange} =
+ case TypeTest of
+ {integer, N} ->
+ compare_with_integer(N, OldVarRange);
+ integer ->
+ {inf(any_range(), OldVarRange), inf(none_range(), OldVarRange)};
+ number ->
+ {OldVarRange, OldVarRange};
+ _ ->
+ {inf(none_range(), OldVarRange), OldVarRange}
+ end,
TrueLabel = hipe_icode:type_true_label(Type),
FalseLabel = hipe_icode:type_false_label(Type),
TrueInfo = enter_define({Arg, TrueRange}, Info),
@@ -1201,14 +1195,12 @@ basic_type(#unsafe_update_element{}) -> not_analysed.
analyse_bs_get_integer(Size, Flags, true) ->
Signed = Flags band 4,
- if Signed =:= 0 ->
- Max = inf_add(inf_bsl(1, Size), -1),
- Min = 0;
- true ->
- Max = inf_add(inf_bsl(1, Size-1), -1),
- Min = inf_inv(inf_bsl(1, Size-1))
- end,
- {Min, Max};
+ case Signed =:= 0 of
+ true ->
+ {0, inf_add(inf_bsl(1, Size), -1)}; % return {Min, Max}
+ false ->
+ {inf_inv(inf_bsl(1, Size-1)), inf_add(inf_bsl(1, Size-1), -1)}
+ end;
analyse_bs_get_integer(Size, Flags, false) when is_integer(Size),
is_integer(Flags) ->
any_r().
@@ -1653,7 +1645,7 @@ inf_bsl(Number1, Number2) when is_integer(Number1), is_integer(Number2) ->
%% State
--spec state__init(cfg(), data()) -> #state{}.
+-spec state__init(cfg(), data()) -> state().
state__init(Cfg, {MFA, ArgsFun, CallFun, FinalFun}) ->
Start = hipe_icode_cfg:start_label(Cfg),
@@ -1676,19 +1668,19 @@ state__init(Cfg, {MFA, ArgsFun, CallFun, FinalFun}) ->
lookup_fun=CallFun, result_action=FinalFun}
end.
--spec state__cfg(#state{}) -> cfg().
+-spec state__cfg(state()) -> cfg().
state__cfg(#state{cfg=Cfg}) ->
Cfg.
--spec state__bb(#state{}, label()) -> bb().
+-spec state__bb(state(), label()) -> bb().
state__bb(#state{cfg=Cfg}, Label) ->
BB = hipe_icode_cfg:bb(Cfg, Label),
true = hipe_bb:is_bb(BB), % Just an assert
BB.
--spec state__bb_add(#state{}, label(), bb()) -> #state{}.
+-spec state__bb_add(state(), label(), bb()) -> state().
state__bb_add(S=#state{cfg=Cfg}, Label, BB) ->
NewCfg = hipe_icode_cfg:bb_add(Cfg, Label, BB),
@@ -1774,14 +1766,12 @@ join_info_in([Var|Left], Info1, Info2, Acc, Changed) ->
NewTree = gb_trees:insert(Var, Val, Acc),
join_info_in(Left, Info1, Info2, NewTree, Changed);
{{value, Val1}, {value, Val2}} ->
- NewVal =
+ {NewChanged, NewVal} =
case sup(Val1, Val2) of
Val1 ->
- NewChanged = Changed,
- Val1;
+ {Changed, Val1};
Val ->
- NewChanged = true,
- Val
+ {true, Val}
end,
NewTree = gb_trees:insert(Var, NewVal, Acc),
join_info_in(Left, Info1, Info2, NewTree, NewChanged)
diff --git a/lib/hipe/icode/hipe_icode_type.erl b/lib/hipe/icode/hipe_icode_type.erl
index e3ba00c5e9..794c27ebcc 100644
--- a/lib/hipe/icode/hipe_icode_type.erl
+++ b/lib/hipe/icode/hipe_icode_type.erl
@@ -105,6 +105,7 @@
ret_type = [t_none()] :: [erl_types:erl_type()],
lookupfun :: call_fun(),
resultaction :: final_fun()}).
+-type state() :: #state{}.
%%-----------------------------------------------------------------------
%% The main exported function
@@ -193,7 +194,7 @@ analyse(Cfg, Data) ->
catch throw:no_input -> ok % No need to do anything since we have no input
end.
--spec safe_analyse(cfg(), data()) -> #state{}.
+-spec safe_analyse(cfg(), data()) -> state().
safe_analyse(Cfg, {MFA,_,_,_}=Data) ->
State = new_state(Cfg, Data),
@@ -363,6 +364,7 @@ call_always_fails(#icode_call{} = I, Info) ->
%% These can actually be calls too.
{erlang, halt, 0} -> false;
{erlang, halt, 1} -> false;
+ {erlang, halt, 2} -> false;
{erlang, exit, 1} -> false;
{erlang, error, 1} -> false;
{erlang, error, 2} -> false;
@@ -460,24 +462,24 @@ integer_range_inequality_propagation(Op, A1, A2, TrueLab, FalseLab, Info) ->
NonIntArg1 = t_subtract(Arg1, t_integer()),
NonIntArg2 = t_subtract(Arg2, t_integer()),
?ineq_debug("nonintargs", [NonIntArg1,NonIntArg2]),
- case t_is_none(IntArg1) or t_is_none(IntArg2) of
+ case t_is_none(IntArg1) orelse t_is_none(IntArg2) of
true ->
?ineq_debug("one is none", [IntArg1,IntArg2]),
[{TrueLab, Info}, {FalseLab, Info}];
false ->
- case Op of
- '>=' ->
- {FalseArg1, FalseArg2, TrueArg1, TrueArg2} =
- integer_range_less_then_propagator(IntArg1, IntArg2);
- '>' ->
- {TrueArg2, TrueArg1, FalseArg2, FalseArg1} =
- integer_range_less_then_propagator(IntArg2, IntArg1);
- '<' ->
- {TrueArg1, TrueArg2, FalseArg1, FalseArg2} =
- integer_range_less_then_propagator(IntArg1, IntArg2);
- '=<' ->
- {FalseArg2, FalseArg1, TrueArg2, TrueArg1} =
- integer_range_less_then_propagator(IntArg2, IntArg1)
+ {TrueArg1, TrueArg2, FalseArg1, FalseArg2} =
+ case Op of
+ '>=' ->
+ {FA1, FA2, TA1, TA2} = int_range_lt_propagator(IntArg1, IntArg2),
+ {TA1, TA2, FA1, FA2};
+ '>' ->
+ {TA2, TA1, FA2, FA1} = int_range_lt_propagator(IntArg2, IntArg1),
+ {TA1, TA2, FA1, FA2};
+ '<' ->
+ int_range_lt_propagator(IntArg1, IntArg2);
+ '=<' ->
+ {FA2, FA1, TA2, TA1} = int_range_lt_propagator(IntArg2, IntArg1),
+ {TA1, TA2, FA1, FA2}
end,
?ineq_debug("int res", [TrueArg1, TrueArg2, FalseArg1, FalseArg2]),
False = {FalseLab, enter(A1, t_sup(FalseArg1, NonIntArg1),
@@ -487,7 +489,7 @@ integer_range_inequality_propagation(Op, A1, A2, TrueLab, FalseLab, Info) ->
[True, False]
end.
-integer_range_less_then_propagator(IntArg1, IntArg2) ->
+int_range_lt_propagator(IntArg1, IntArg2) ->
Min1 = number_min(IntArg1),
Max1 = number_max(IntArg1),
Min2 = number_min(IntArg2),
generated by cgit v1.2.3 (git 2.25.1) at 2025-03-05 08:01:42 +0000