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| author | Björn Gustavsson <[email protected]> | 2016-09-26 15:01:19 +0200 |
|---|---|---|
| committer | Björn Gustavsson <[email protected]> | 2016-10-05 13:00:45 +0200 |
| commit | 0c599bcad1e7f5f66dd2342ab27791048145e892 (patch) | |
| tree | 2f9702b3f3c829d6862df0cc193d5abc394251b4 /lib/compiler/src/beam_utils.erl | |
| parent | 3f3f25b23379b1afb15cc97462cf5d385690f5a0 (diff) | |
| download | otp-0c599bcad1e7f5f66dd2342ab27791048145e892.tar.gz otp-0c599bcad1e7f5f66dd2342ab27791048145e892.tar.bz2 otp-0c599bcad1e7f5f66dd2342ab27791048145e892.zip | |
beam_block: Avoid unsafe inclusion of get_map_elements in blocks
c2035ebb8b restricted the get_map_elements instruction so that it
could only occur at the beginning of a block. It turns out that
including it anywhere in a block is unsafe.
Therefore, never put get_map_elements instruction in blocks.
(Also remove the beam_utils:join_even/2 function since it is no
longer used.)
ERL-266
Diffstat (limited to 'lib/compiler/src/beam_utils.erl')
| -rw-r--r-- | lib/compiler/src/beam_utils.erl | 12 |
1 files changed, 6 insertions, 6 deletions
diff --git a/lib/compiler/src/beam_utils.erl b/lib/compiler/src/beam_utils.erl index a15ecf633e..249d9395ca 100644 --- a/lib/compiler/src/beam_utils.erl +++ b/lib/compiler/src/beam_utils.erl @@ -26,7 +26,7 @@ empty_label_index/0,index_label/3,index_labels/1, code_at/2,bif_to_test/3,is_pure_test/1, live_opt/1,delete_live_annos/1,combine_heap_needs/2, - join_even/2,split_even/1]). + split_even/1]). -import(lists, [member/2,sort/1,reverse/1,splitwith/2]). @@ -233,11 +233,6 @@ combine_heap_needs(H1, H2) when is_integer(H1), is_integer(H2) -> split_even(Rs) -> split_even(Rs, [], []). -%% join_even/1 -%% {[1,3,5],[2,4,6]} -> [1,2,3,4,5,6] - -join_even([], []) -> []; -join_even([S|Ss], [D|Ds]) -> [S,D|join_even(Ss, Ds)]. %%% %%% Local functions. @@ -753,6 +748,11 @@ live_opt([timeout=I|Is], _, D, Acc) -> live_opt(Is, 0, D, [I|Acc]); live_opt([{wait,_}=I|Is], _, D, Acc) -> live_opt(Is, 0, D, [I|Acc]); +live_opt([{get_map_elements,Fail,Src,{list,List}}=I|Is], Regs0, D, Acc) -> + {Ss,Ds} = split_even(List), + Regs1 = x_live([Src|Ss], x_dead(Ds, Regs0)), + Regs = live_join_label(Fail, D, Regs1), + live_opt(Is, Regs, D, [I|Acc]); %% Transparent instructions - they neither use nor modify x registers. live_opt([{deallocate,_}=I|Is], Regs, D, Acc) -> |