diff options
| -rw-r--r-- | erts/emulator/beam/beam_load.c | 19 | ||||
| -rw-r--r-- | erts/emulator/beam/bs_instrs.tab | 11 | ||||
| -rw-r--r-- | erts/emulator/beam/ops.tab | 1 | ||||
| -rw-r--r-- | erts/emulator/test/bs_match_misc_SUITE.erl | 21 |
4 files changed, 25 insertions, 27 deletions
diff --git a/erts/emulator/beam/beam_load.c b/erts/emulator/beam/beam_load.c index 21740caa2c..d0936060b8 100644 --- a/erts/emulator/beam/beam_load.c +++ b/erts/emulator/beam/beam_load.c @@ -3347,19 +3347,12 @@ gen_get_binary2(LoaderState* stp, GenOpArg Fail, GenOpArg Ms, GenOpArg Live, NATIVE_ENDIAN(Flags); if (Size.type == TAG_a && Size.val == am_all) { - if (Ms.type == Dst.type && Ms.val == Dst.val) { - GENOP_NAME_ARITY(op, i_bs_get_binary_all_reuse, 3); - op->a[0] = Ms; - op->a[1] = Fail; - op->a[2] = Unit; - } else { - GENOP_NAME_ARITY(op, i_bs_get_binary_all2, 5); - op->a[0] = Ms; - op->a[1] = Fail; - op->a[2] = Live; - op->a[3] = Unit; - op->a[4] = Dst; - } + GENOP_NAME_ARITY(op, i_bs_get_binary_all2, 5); + op->a[0] = Ms; + op->a[1] = Fail; + op->a[2] = Live; + op->a[3] = Unit; + op->a[4] = Dst; } else if (Size.type == TAG_i) { GENOP_NAME_ARITY(op, i_bs_get_binary_imm2, 6); op->a[0] = Ms; diff --git a/erts/emulator/beam/bs_instrs.tab b/erts/emulator/beam/bs_instrs.tab index 652460a66d..9cad2b03c5 100644 --- a/erts/emulator/beam/bs_instrs.tab +++ b/erts/emulator/beam/bs_instrs.tab @@ -1136,7 +1136,6 @@ i_bs_get_utf16.execute(Fail, Flags, Dst) { } bs_context_to_binary := ctx_to_bin.fetch.execute; -i_bs_get_binary_all_reuse := ctx_to_bin.fetch_bin.execute; ctx_to_bin.head() { Eterm context; @@ -1159,16 +1158,6 @@ ctx_to_bin.fetch(Src) { } } -ctx_to_bin.fetch_bin(Src, Fail, Unit) { - context = $Src; - mb = ms_matchbuffer(context); - size = mb->size - mb->offset; - if (size % $Unit != 0) { - $FAIL($Fail); - } - offs = mb->offset; -} - ctx_to_bin.execute() { Uint hole_size; Uint orig = mb->orig; diff --git a/erts/emulator/beam/ops.tab b/erts/emulator/beam/ops.tab index 6832e65b1b..abbddbb41f 100644 --- a/erts/emulator/beam/ops.tab +++ b/erts/emulator/beam/ops.tab @@ -1262,7 +1262,6 @@ bs_get_binary2 Fail=f Ms=xy Live=u Sz=sq Unit=u Flags=u Dst=d => \ i_bs_get_binary_imm2 xy f? t W t d i_bs_get_binary2 xy f t? s t d i_bs_get_binary_all2 xy f? t t d -i_bs_get_binary_all_reuse xy f? t # Fetching float from binaries. bs_get_float2 Fail=f Ms=xy Live=u Sz=s Unit=u Flags=u Dst=d => \ diff --git a/erts/emulator/test/bs_match_misc_SUITE.erl b/erts/emulator/test/bs_match_misc_SUITE.erl index 17759d78f3..cae4eb54d2 100644 --- a/erts/emulator/test/bs_match_misc_SUITE.erl +++ b/erts/emulator/test/bs_match_misc_SUITE.erl @@ -24,7 +24,7 @@ kenneth/1,encode_binary/1,native/1,happi/1, size_var/1,wiger/1,x0_context/1,huge_float_field/1, writable_binary_matched/1,otp_7198/1,unordered_bindings/1, - float_middle_endian/1]). + float_middle_endian/1,unsafe_get_binary_reuse/1]). -include_lib("common_test/include/ct.hrl"). @@ -36,7 +36,8 @@ all() -> [bound_var, bound_tail, t_float, little_float, sean, kenneth, encode_binary, native, happi, size_var, wiger, x0_context, huge_float_field, writable_binary_matched, - otp_7198, unordered_bindings, float_middle_endian]. + otp_7198, unordered_bindings, float_middle_endian, + unsafe_get_binary_reuse]. %% Test matching of bound variables. @@ -556,5 +557,21 @@ unordered_bindings(CompressedLength, HashSize, PadLength, T) -> Padding:PadLength/binary,PadLength>> = T, {Content,Mac,Padding}. +%% ERL-901: A load-time optimization assumed that match contexts had no further +%% uses when a bs_get_binary2 overwrote the match context's register, and +%% figured it would be safe to reuse the match context's memory for the +%% resulting binary. +%% +%% This is no longer safe as of OTP 22, as a match context may be reused after +%% being passed to another function. +unsafe_get_binary_reuse(Config) when is_list(Config) -> + <<_First, Rest/binary>> = <<"hello">>, + ubgr_1(Rest), + <<Second,_/bits>> = Rest, + $e = Second, + ok. + +ubgr_1(<<_CP/utf8, Rest/binary>>) -> id(Rest); +ubgr_1(_) -> false. id(I) -> I. |