From 09112806c15a81be86730503af36e304ac11d1ed Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Bj=C3=B6rn=20Gustavsson?= Date: Wed, 7 Jun 2017 14:27:15 +0200 Subject: Fix unsafe bit syntax matching optimization As part of sys_core_fold, variables involved in bit syntax matching would be annotated when it would be safe for a later pass to do the delayed sub-binary creation optimization. An implicit assumption regarding the annotation was that the code must not be further optimized. That assumption was broken in 05130e48555891, which introduced a fixpoint iteration (applying the optimizations until there were no more changes). That means that a variable could be annotated as safe for reusing the match context in one iteration, but a later iteration could rewrite the code in a way that would make the optimization unsafe. One way to fix this would be to clear all reuse_for_context annotations before each iteration. But that would be wasteful. Instead I chose to fix the problem by moving out the annotation code to a separate pass (sys_core_bsm) that is run later after all major optimizations of Core Erlang has been done. --- lib/compiler/test/bs_match_SUITE.erl | 19 +++++++++++++++++-- lib/compiler/test/compile_SUITE.erl | 1 + lib/compiler/test/misc_SUITE.erl | 3 ++- lib/compiler/test/warnings_SUITE.erl | 2 +- 4 files changed, 21 insertions(+), 4 deletions(-) (limited to 'lib/compiler/test') diff --git a/lib/compiler/test/bs_match_SUITE.erl b/lib/compiler/test/bs_match_SUITE.erl index 89f851ac3b..106d8eb45a 100644 --- a/lib/compiler/test/bs_match_SUITE.erl +++ b/lib/compiler/test/bs_match_SUITE.erl @@ -39,7 +39,7 @@ match_string_opt/1,select_on_integer/1, map_and_binary/1,unsafe_branch_caching/1, bad_literals/1,good_literals/1,constant_propagation/1, - parse_xml/1]). + parse_xml/1,get_payload/1]). -export([coverage_id/1,coverage_external_ignore/2]). @@ -70,7 +70,8 @@ groups() -> no_partition,calling_a_binary,binary_in_map, match_string_opt,select_on_integer, map_and_binary,unsafe_branch_caching, - bad_literals,good_literals,constant_propagation,parse_xml]}]. + bad_literals,good_literals,constant_propagation,parse_xml, + get_payload]}]. init_per_suite(Config) -> @@ -1508,6 +1509,20 @@ do_parse_xml(<<"> = Bytes) -> is_next_char_whitespace(<>) -> C =:= $\s. +-record(ext_header, + {this_hdr = 17, + ext_hdr_opts}). + +get_payload(Config) -> + <<3445:48>> = do_get_payload(#ext_header{ext_hdr_opts = <<3445:48>>}), + {'EXIT',_} = (catch do_get_payload(#ext_header{})), + ok. + +do_get_payload(ExtHdr) -> + _ = ExtHdr#ext_header.this_hdr, + ExtHdrOptions = ExtHdr#ext_header.ext_hdr_opts, + <<_:13,_:35>> = ExtHdr#ext_header.ext_hdr_opts, + ExtHdrOptions. check(F, R) -> R = F(). diff --git a/lib/compiler/test/compile_SUITE.erl b/lib/compiler/test/compile_SUITE.erl index 4e2753ba5f..f647a4030d 100644 --- a/lib/compiler/test/compile_SUITE.erl +++ b/lib/compiler/test/compile_SUITE.erl @@ -371,6 +371,7 @@ do_file_listings(DataDir, PrivDir, [File|Files]) -> do_listing(Simple, TargetDir, dinline, ".inline"), do_listing(Simple, TargetDir, dcore, ".core"), do_listing(Simple, TargetDir, dcopt, ".copt"), + do_listing(Simple, TargetDir, dcbsm, ".core_bsm"), do_listing(Simple, TargetDir, dsetel, ".dsetel"), do_listing(Simple, TargetDir, dkern, ".kernel"), do_listing(Simple, TargetDir, dlife, ".life"), diff --git a/lib/compiler/test/misc_SUITE.erl b/lib/compiler/test/misc_SUITE.erl index 01b064cc10..4bd884d86b 100644 --- a/lib/compiler/test/misc_SUITE.erl +++ b/lib/compiler/test/misc_SUITE.erl @@ -161,11 +161,12 @@ md5_1(Beam) -> %% Cover some code that handles internal errors. silly_coverage(Config) when is_list(Config) -> - %% sys_core_fold, sys_core_setel, v3_kernel + %% sys_core_fold, sys_core_bsm, sys_core_setel, v3_kernel BadCoreErlang = {c_module,[], name,[],[], [{{c_var,[],{foo,2}},seriously_bad_body}]}, expect_error(fun() -> sys_core_fold:module(BadCoreErlang, []) end), + expect_error(fun() -> sys_core_bsm:module(BadCoreErlang, []) end), expect_error(fun() -> sys_core_dsetel:module(BadCoreErlang, []) end), expect_error(fun() -> v3_kernel:module(BadCoreErlang, []) end), diff --git a/lib/compiler/test/warnings_SUITE.erl b/lib/compiler/test/warnings_SUITE.erl index 7c27750556..77e4234c70 100644 --- a/lib/compiler/test/warnings_SUITE.erl +++ b/lib/compiler/test/warnings_SUITE.erl @@ -529,7 +529,7 @@ bin_opt_info(Config) when is_list(Config) -> Code, [bin_opt_info], {warnings, - [{4,sys_core_fold,orig_bin_var_used_in_guard}, + [{4,sys_core_bsm,orig_bin_var_used_in_guard}, {5,beam_bsm,{no_bin_opt,{{t1,1},no_suitable_bs_start_match}}}, {9,beam_bsm,{no_bin_opt, {binary_used_in,{extfunc,erlang,split_binary,2}}}} ]}}], -- cgit v1.2.3