diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/compiler/src/beam_utils.erl | 62 |
1 files changed, 36 insertions, 26 deletions
diff --git a/lib/compiler/src/beam_utils.erl b/lib/compiler/src/beam_utils.erl index fbcd5de1bb..1945fadfd3 100644 --- a/lib/compiler/src/beam_utils.erl +++ b/lib/compiler/src/beam_utils.erl @@ -779,37 +779,47 @@ live_opt([{recv_mark,_}=I|Is], Regs, D, Acc) -> live_opt([], _, _, Acc) -> Acc. -live_opt_block([{set,Ds,Ss,Op}=I0|Is], Regs0, D, Acc) -> +live_opt_block([{set,Ds,Ss,Op0}|Is], Regs0, D, Acc) -> Regs1 = x_live(Ss, x_dead(Ds, Regs0)), - {I,Regs} = case Op of - {alloc,Live0,Alloc} -> - %% The life-time analysis used by the code generator - %% is sometimes too conservative, so it may be - %% possible to lower the number of live registers - %% based on the exact liveness information. - %% The main benefit is that more optimizations that - %% depend on liveness information (such as the - %% beam_bool and beam_dead passes) may be applied. - Live = live_regs(Regs1), - true = Live =< Live0, %Assertion. - I1 = {set,Ds,Ss,{alloc,Live,Alloc}}, - {I1,live_call(Live)}; - _ -> - {I0,Regs1} - end, + {Op, Regs} = live_opt_block_op(Op0, Regs1, D), + I = {set, Ds, Ss, Op}, + case Ds of - [{x,X}] -> - case (not is_live(X, Regs0)) andalso Op =:= move of - true -> - live_opt_block(Is, Regs0, D, Acc); - false -> - live_opt_block(Is, Regs, D, [I|Acc]) - end; - _ -> - live_opt_block(Is, Regs, D, [I|Acc]) + [{x,X}] -> + case (not is_live(X, Regs0)) andalso Op =:= move of + true -> + live_opt_block(Is, Regs0, D, Acc); + false -> + live_opt_block(Is, Regs, D, [I|Acc]) + end; + _ -> + live_opt_block(Is, Regs, D, [I|Acc]) end; + live_opt_block([], Regs, _, Acc) -> {Acc,Regs}. +live_opt_block_op({alloc,Live0,AllocOp}, Regs0, D) -> + Regs = + case AllocOp of + {Kind, _N, Fail} when Kind =:= gc_bif; Kind =:= put_map -> + live_join_label(Fail, D, Regs0); + _ -> + Regs0 + end, + + %% The life-time analysis used by the code generator is sometimes too + %% conservative, so it may be possible to lower the number of live + %% registers based on the exact liveness information. The main benefit is + %% that more optimizations that depend on liveness information (such as the + %% beam_bool and beam_dead passes) may be applied. + Live = live_regs(Regs), + true = Live =< Live0, + {{alloc,Live,AllocOp}, live_call(Live)}; +live_opt_block_op({bif,_N,Fail} = Op, Regs, D) -> + {Op, live_join_label(Fail, D, Regs)}; +live_opt_block_op(Op, Regs, _D) -> + {Op, Regs}. + live_join_labels([{f,L}|T], D, Regs0) when L =/= 0 -> Regs = gb_trees:get(L, D) bor Regs0, live_join_labels(T, D, Regs); |