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-rw-r--r--lib/compiler/src/beam_bsm.erl68
-rw-r--r--lib/compiler/src/beam_jump.erl2
-rw-r--r--lib/compiler/src/beam_utils.erl18
-rw-r--r--lib/compiler/src/v3_codegen.erl1
4 files changed, 54 insertions, 35 deletions
diff --git a/lib/compiler/src/beam_bsm.erl b/lib/compiler/src/beam_bsm.erl
index 37053e1cc4..02794a8e18 100644
--- a/lib/compiler/src/beam_bsm.erl
+++ b/lib/compiler/src/beam_bsm.erl
@@ -241,21 +241,45 @@ btb_reaches_match_2([{bif,_,{f,F},Ss,Dst}=I|Is], Regs0, D0) ->
Regs = btb_kill([Dst], Regs0),
D = btb_follow_branch(F, Regs, D0),
btb_reaches_match_1(Is, Regs, D);
-btb_reaches_match_2([{test,bs_start_match2,_,_,[Ctx,_],Ctx}|Is], Regs, D) ->
- case btb_context_regs(Regs) of
- [Ctx] ->
- D;
- CtxRegs ->
- case member(Ctx, CtxRegs) of
- false -> btb_reaches_match_2(Is, Regs, D);
- true -> btb_error(unsuitable_bs_start_match)
+btb_reaches_match_2([{test,bs_start_match2,{f,F},Live,[Ctx,_],Ctx}=I|Is],
+ Regs0, D0) ->
+ CtxRegs = btb_context_regs(Regs0),
+ case member(Ctx, CtxRegs) of
+ false ->
+ %% This bs_start_match2 instruction does not use "our"
+ %% match state. Therefore we can continue the search
+ %% for another bs_start_match2 instruction.
+ D = btb_follow_branch(F, Regs0, D0),
+ Regs = btb_kill_not_live(Live, Regs0),
+ btb_reaches_match_2(Is, Regs, D);
+ true ->
+ %% OK. This instruction will use "our" match state,
+ %% but we must make sure that all other copies of the
+ %% match state are killed in the code that follows
+ %% the instruction. (We know that the fail branch cannot
+ %% be taken in this case.)
+ OtherCtxRegs = CtxRegs -- [Ctx],
+ case btb_are_all_unused(OtherCtxRegs, Is, D0) of
+ false -> btb_error({OtherCtxRegs,not_all_unused_after,I});
+ true -> D0
end
end;
-btb_reaches_match_2([{test,bs_start_match2,_,_,[Bin,_],Ctx}|Is], Regs, D) ->
- CtxRegs = btb_context_regs(Regs),
+btb_reaches_match_2([{test,bs_start_match2,{f,F},Live,[Bin,_],Ctx}|Is],
+ Regs0, D0) ->
+ CtxRegs = btb_context_regs(Regs0),
case member(Bin, CtxRegs) orelse member(Ctx, CtxRegs) of
- false -> btb_reaches_match_2(Is, Regs, D);
- true -> btb_error(unsuitable_bs_start_match)
+ false ->
+ %% This bs_start_match2 does not reference any copy of the
+ %% match state. Therefore it can safely be passed on the
+ %% way to another (perhaps more suitable) bs_start_match2
+ %% instruction.
+ D = btb_follow_branch(F, Regs0, D0),
+ Regs = btb_kill_not_live(Live, Regs0),
+ btb_reaches_match_2(Is, Regs, D);
+ true ->
+ %% This variant of the bs_start_match2 instruction does
+ %% not accept a match state as source.
+ btb_error(unsuitable_bs_start_match)
end;
btb_reaches_match_2([{test,_,{f,F},Ss}=I|Is], Regs, D0) ->
btb_ensure_not_used(Ss, I, Regs),
@@ -287,11 +311,11 @@ btb_reaches_match_2([{bs_restore2,Src,_}=I|Is], Regs0, D) ->
btb_reaches_match_1(Is, Regs0, D);
true ->
%% Check that all other copies of the context registers
- %% are killed by the following instructions.
+ %% are unused by the following instructions.
Regs = btb_kill([Src], Regs0),
CtxRegs = btb_context_regs(Regs),
- case btb_are_all_killed(CtxRegs, Is, D) of
- false -> btb_error({CtxRegs,not_all_killed_after,I});
+ case btb_are_all_unused(CtxRegs, Is, D) of
+ false -> btb_error({CtxRegs,not_all_unused_after,I});
true -> D#btb{must_not_save=true}
end
end;
@@ -301,11 +325,11 @@ btb_reaches_match_2([{bs_context_to_binary,Src}=I|Is], Regs0, D) ->
btb_reaches_match_1(Is, Regs0, D);
true ->
%% Check that all other copies of the context registers
- %% are killed by the following instructions.
+ %% are unused by the following instructions.
Regs = btb_kill([Src], Regs0),
CtxRegs = btb_context_regs(Regs),
- case btb_are_all_killed(CtxRegs, Is, D) of
- false -> btb_error({CtxRegs,not_all_killed_after,I});
+ case btb_are_all_unused(CtxRegs, Is, D) of
+ false -> btb_error({CtxRegs,not_all_unused_after,I});
true -> D#btb{must_not_save=true}
end
end;
@@ -343,7 +367,7 @@ btb_call(Arity, Lbl, Regs0, Is, D0) ->
%% tucked away in a y register.
RegList = btb_context_regs(Regs),
YRegs = [R || {y,_}=R <- RegList],
- case btb_are_all_killed(YRegs, Is, D) of
+ case btb_are_all_unused(YRegs, Is, D) of
true -> D;
false -> btb_error({multiple_uses,RegList})
end;
@@ -426,11 +450,11 @@ btb_reaches_match_block([], Regs) ->
Regs.
%% btb_are_all_killed([Register], [Instruction], D) -> true|false
-%% Test whether all of the register are killed in the instruction stream.
+%% Test whether all of the register are unused in the instruction stream.
-btb_are_all_killed(RegList, Is, #btb{index=Li}) ->
+btb_are_all_unused(RegList, Is, #btb{index=Li}) ->
all(fun(R) ->
- beam_utils:is_killed(R, Is, Li)
+ beam_utils:is_not_used(R, Is, Li)
end, RegList).
%% btp_regs_from_list([Register]) -> RegisterSet.
diff --git a/lib/compiler/src/beam_jump.erl b/lib/compiler/src/beam_jump.erl
index b05d01b2a1..636c299e47 100644
--- a/lib/compiler/src/beam_jump.erl
+++ b/lib/compiler/src/beam_jump.erl
@@ -220,6 +220,8 @@ extract_seq([{line,_}=Line|Is], Acc) ->
extract_seq(Is, [Line|Acc]);
extract_seq([{block,_}=Bl|Is], Acc) ->
extract_seq_1(Is, [Bl|Acc]);
+extract_seq([{bs_context_to_binary,_}=I|Is], Acc) ->
+ extract_seq_1(Is, [I|Acc]);
extract_seq([{label,_}|_]=Is, Acc) ->
extract_seq_1(Is, Acc);
extract_seq(_, _) -> no.
diff --git a/lib/compiler/src/beam_utils.erl b/lib/compiler/src/beam_utils.erl
index 8b661e6901..8af0447f63 100644
--- a/lib/compiler/src/beam_utils.erl
+++ b/lib/compiler/src/beam_utils.erl
@@ -263,19 +263,11 @@ check_liveness(R, [{test,_,{f,Fail},As}|Is], St0) ->
{_,_}=Other -> Other
end
end;
-check_liveness(R, [{test,_,{f,Fail},Live,Ss,_}|Is], St0) ->
- case R of
- {x,X} ->
- case X < Live orelse member(R, Ss) of
- true -> {used,St0};
- false -> check_liveness_at(R, Fail, St0)
- end;
- {y,_} ->
- case check_liveness_at(R, Fail, St0) of
- {killed,St} -> check_liveness(R, Is, St);
- {_,_}=Other -> Other
- end
- end;
+check_liveness(R, [{test,Op,Fail,Live,Ss,Dst}|Is], St) ->
+ %% Check this instruction as a block to get a less conservative
+ %% result if the caller is is_not_used/3.
+ Block = [{set,[Dst],Ss,{alloc,Live,{bif,Op,Fail}}}],
+ check_liveness(R, [{block,Block}|Is], St);
check_liveness(R, [{select,_,R,_,_}|_], St) ->
{used,St};
check_liveness(R, [{select,_,_,Fail,Branches}|_], St) ->
diff --git a/lib/compiler/src/v3_codegen.erl b/lib/compiler/src/v3_codegen.erl
index 3b73269545..6a13495523 100644
--- a/lib/compiler/src/v3_codegen.erl
+++ b/lib/compiler/src/v3_codegen.erl
@@ -379,6 +379,7 @@ bsm_rename_ctx(#l{ke={test,_,_}}=L, _, _, _) -> L;
bsm_rename_ctx(#l{ke={bif,_,_,_}}=L, _, _, _) -> L;
bsm_rename_ctx(#l{ke={gc_bif,_,_,_}}=L, _, _, _) -> L;
bsm_rename_ctx(#l{ke={set,_,_}}=L, _, _, _) -> L;
+bsm_rename_ctx(#l{ke={call,_,_,_}}=L, _, _, _) -> L;
bsm_rename_ctx(#l{ke={block,_}}=L, Old, _, false) ->
%% This block is not inside a protected. The match context variable cannot
%% possibly be live inside the block.
generated by cgit v1.2.3 (git 2.25.1) at 2025-01-29 06:43:49 +0000