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2016-01-11Eliminate crash in v3_codegenBjörn Gustavsson
The following code would crash v3_codegen: order(From) -> catch if From#{[] => sufficient} -> saint end. Before explaining the crash, first some background on the stack frame and the Y registers. Certain instructions, most notably the 'call' instructions, clobber all X registers. Before any such instruction, all X registers that have values that will be used after the call must be saved to Y registers (i.e. to the stack frame). adjust_stack/4 will be called when X registers must be saved. There is also another situation when X registers must be saved, namely within a 'catch' if we are about to execute any instruction that may cause an exception. Examples of such instructions are some guard BIFs (such as length/1) and construction of binaries or maps. Within a 'catch', X registers must be be saved because if an exception is thrown and catched all X registers will be destroyed. The same adjust_stack/4 function will be called for those instructions, but only if they occur within a 'catch'. There is actually one more complication. If there is code in a guard within a catch, the X registers should not be saved, because the code in a guard never clobbers any X registers that were alive before the guard code was entered. v3_codegen is written with the implicit assumption that code in guards never cause anything to be saved to Y registers. The code for building maps and binaries would incorrectly save X registers within a guard inside a 'catch'. For construction of binaries, that would mean that a useless but harmelss 'move' instruction was generated. But for construction of maps, the saving of the Y register would not be harmless. There would be a crash when attempting to merge #sr{} records. #sr{} records keeps track of the contents of X and Y registers. When two separate code paths are joined (e.g. at the end of 'case' statement), the register descriptors must be reconciled. Basically, the register descriptors for both paths must be identical. The #sr{} record for one path must not claim that {y,0} contains a certain value, while another path claims that {y,0} is dead. Thus, the crash occurs in sr_merge/2 when failing to reconcile the Y registers. To fix this bug this bug we will introduce a new function called maybe_adjust_stack/5. It will save X registers on the stack only if the code is inside a catch but not inside a guard. We will change all existing code to use this new function when appropriate. Reported-by: Thomas Arts
2016-01-07Merge branch 'bjorn/compiler/beam_bool/OTP-13208' into maintBjörn Gustavsson
* bjorn/compiler/beam_bool/OTP-13208: beam_bool: Fix unsafe optimization
2016-01-07beam_bool: Fix unsafe optimizationBjörn Gustavsson
beam_bool would make the following code unsafe (which would be reported by beam_validator): scotland(Echo) -> found(case Echo of Echo when true; Echo, Echo, Echo -> Echo; echo -> [] end, Echo = placed). found(_, _) -> million. Basically, beam_bool would see that the 'case' would always return the value of Echo. Thus: scotland(Echo) -> found(Echo, Echo = placed). The only problem is that beam_bool would also remove a 'move' instruction that would save Echo to the stack. Here is the assembly code for part of the function: {allocate_zero,1,1}. {move,{x,0},{y,0}}. %% Save Echo on stack. {bif,'=:=',{f,7},[{x,0},{atom,true}],{x,1}}. {bif,'=:=',{f,7},[{x,0},{atom,true}],{x,2}}. {bif,'=:=',{f,7},[{x,0},{atom,true}],{x,3}}. {bif,'and',{f,7},[{x,2},{x,3}],{x,2}}. {bif,'and',{f,7},[{x,1},{x,2}],{x,1}}. {jump,{f,8}}. {label,7}. {move,{atom,false},{x,1}}. {label,8}. {bif,'or',{f,6},[{atom,true},{x,1}],{x,1}}. {test,is_eq_exact,{f,6},[{x,1},{atom,true}]}. %% Jump never taken. {jump,{f,5}}. {label,6}. {test,is_eq_exact,{f,9},[{x,0},{atom,echo}]}. {move,nil,{x,0}}. {jump,{f,5}}. {label,9}. {test_heap,3,0}. {put_tuple,2,{x,0}}. {put,{atom,case_clause}}. {put,{y,0}}. {line,[{location,"t.erl",5}]}. {call_ext,1,{extfunc,erlang,error,1}}. {jump,{f,5}}. {label,5}. {test,is_eq_exact,{f,12},[{atom,placed},{y,0}]}. beam_bool would see that the is_eq_exact test at label 8 would always succeed. It could therefore remove most of the code before the jump to label 5. Unfortunately it also removed the essential move of Echo to the stack: {allocate_zero,1,1}. %% Instruction incorrectly removed: {move,{x,0},{y,0}}. {jump,{f,5}}. {label,5}. {test,is_eq_exact,{f,12},[{atom,placed},{y,0}]}. The root cause of the problem is that the 'move' instruction is included in the block of 'bif' instructions before label 8. Normally the 'move' instruction would not have been discarded, but because the left operand to the 'or' BIF is 'true', the entire block with 'bif' instructions are dropped. As far as I can see, there is no gain by including 'move' instructions in the first place. There is no way that better code will be produced. In fact, the entire optimization can be given up if 'move' instructions are found in the block. Thus we can fix this bug by never including any 'move' instructions in the block of 'bif' instructions. We can also remove all the code that deals with 'move' instructions within blocks. Reported-by: Thomas Arts
2015-12-28Merge branch 'legoscia/tls_dist_error_reporting' into maintZandra
* legoscia/tls_dist_error_reporting: Report bad options for outgoing TLS distribution Save error reasons for TLS distribution connections Report bad options for TLS distribution connections OTP-13219
2015-12-28Merge branch 'josevalim/jv-map-fun-eval-maint' into maintZandra
* josevalim/jv-map-fun-eval-maint: Use full list of bindings when matching on map keys OTP-13218
2015-12-28Merge branch 'lucafavatella/dialyzer-fun-call' into maintZandra
* lucafavatella/dialyzer-fun-call: Teach Dialyzer call to funs `M:F/A` (literal M, F, A) OTP-13217
2015-12-22Merge branch 'maint-17' into maintAnders Svensson
2015-12-22ssh: clean test specsHans Nilsson
2015-12-22Merge branch 'hans/ssh/cuddle_tests' into maintHans Nilsson
* hans/ssh/cuddle_tests: ssh: add econnaborted to disconnect msgs in test suite ssh: fix the check that open-ssh supports certain pubkeys in a test suite
2015-12-22ssh: fix error (wrong suite) in test/ssh.specHans Nilsson
2015-12-21ssh: benchmark all common kex and cipher algorithmsHans Nilsson
2015-12-21New structure of the reportHans Nilsson
2015-12-21ssh: ssh_benchmark_SUITE re-organizedHans Nilsson
2015-12-21ssh: Add first version of ssh_benchmark_SUITEHans Nilsson
2015-12-20Update release notesErlang/OTP
2015-12-20Merge branch 'anders/diameter/17.5.6.7/OTP-13211' into maint-17Erlang/OTP
* anders/diameter/17.5.6.7/OTP-13211: vsn -> 1.9.2.2 Update/fix appup for 17.5.6.7 Be resilient to diameter_service state upgrades
2015-12-20Merge branch 'anders/diameter/request_leak/OTP-13137' into maint-17Erlang/OTP
* anders/diameter/request_leak/OTP-13137: Fix request table leak at retransmission Fix request table leak at exit signal
2015-12-20Merge branch 'anders/diameter/17/watchdog/OTP-12969' into maint-17Erlang/OTP
* anders/diameter/17/watchdog/OTP-12969: Fix watchdog function_clause
2015-12-20Merge branch 'anders/diameter/M-bit/OTP-12947' into maint-17Erlang/OTP
* anders/diameter/M-bit/OTP-12947: Add service_opt() strict_mbit
2015-12-20vsn -> 1.9.2.2Anders Svensson
2015-12-20Update/fix appup for 17.5.6.7Anders Svensson
OTP-12947 strict_mbit OTP-12969 watchdog function_clause OTP-13137 request leak diameter_config (that allows the new option) should be loaded after the others. Anchor was missing from one regexp. Patches did not accumulate through older versions.
2015-12-20Be resilient to diameter_service state upgradesAnders Svensson
By not failing in code that looks up state: pick_peer and service_info.
2015-12-18ssh: add econnaborted to disconnect msgs in test suiteHans Nilsson
2015-12-18ssh: fix the check that open-ssh supports certain pubkeys in a test suiteHans Nilsson
2015-12-16Merge tag 'OTP-18.2' into maintHenrik Nord
=== OTP-18.2 === Changed Applications: - asn1-4.0.1 - common_test-1.11.1 - compiler-6.0.2 - crypto-3.6.2 - dialyzer-2.8.2 - diameter-1.11.1 - erl_docgen-0.4.1 - erl_interface-3.8.1 - erts-7.2 - eunit-2.2.12 - hipe-3.14 - inets-6.1 - jinterface-1.6.1 - kernel-4.1.1 - observer-2.1.1 - parsetools-2.1.1 - public_key-1.1 - runtime_tools-1.9.2 - sasl-2.6.1 - snmp-5.2.1 - ssh-4.2 - ssl-7.2 - stdlib-2.7 - test_server-3.9.1 - tools-2.8.2 - typer-0.9.10 - wx-1.6 - xmerl-1.3.9 Unchanged Applications: - cosEvent-2.2 - cosEventDomain-1.2 - cosFileTransfer-1.2 - cosNotification-1.2 - cosProperty-1.2 - cosTime-1.2 - cosTransactions-1.3 - debugger-4.1.1 - edoc-0.7.17 - eldap-1.2 - et-1.5.1 - gs-1.6 - ic-4.4 - megaco-3.18 - mnesia-4.13.2 - odbc-2.11.1 - orber-3.8 - os_mon-2.4 - ose-1.1 - otp_mibs-1.1 - percept-0.8.11 - reltool-0.7 - syntax_tools-1.7 - webtool-0.9
2015-12-15Merge branch 'ia/libressl' into maintIngela Anderton Andin
* ia/libressl: ssl: Print openssl version string ssl: Do not use environment variables in openSSL config file
2015-12-15ssl: Convert all test to use "ssl_test_lib:portable_open_port"Ingela Anderton Andin
2015-12-15Update release notesErlang/OTP
2015-12-15Update version numbersErlang/OTP
2015-12-15Merge branch 'ia/libressl' into maintErlang/OTP
* ia/libressl: ssl: Print openssl version string ssl: Do not use environment variables in openSSL config file
2015-12-15Merge branch 'siri/appups-18.2' into maintErlang/OTP
* siri/appups-18.2: Update appups in kernel, stdlib and sasl for OTP-18.2
2015-12-15Merge branch 'ia/inets/dialyzer-custom' into maintIngela Anderton Andin
* ia/inets/dialyzer-custom: inets: Include behaviour modules in install target inets: Fix dialyzer warning
2015-12-15inets: Include behaviour modules in install targetIngela Anderton Andin
2015-12-15inets: Fix dialyzer warningIngela Anderton Andin
2015-12-14ssl: Print openssl version stringIngela Anderton Andin
2015-12-14Merge branch 'zandra/fix-snmp-appup' into maintZandra
* zandra/fix-snmp-appup: correct the snmp app up file
2015-12-14ssl: Do not use environment variables in openSSL config fileIngela Anderton Andin
LibreSSL does not allow it.
2015-12-14Merge branch 'dgud/wx/fix-observer-display' into maintDan Gudmundsson
* dgud/wx/fix-observer-display: wx: Revert part of 617387025b698c
2015-12-14Merge branch 'ia/pr/919/OTP-13189' into maintIngela Anderton Andin
* ia/pr/919/OTP-13189: ssl: fix hibernate_after with instant or near instant timeouts
2015-12-12wx: Revert part of 617387025b698cDan Gudmundsson
Causes issues on mac and observer
2015-12-11ssl: fix hibernate_after with instant or near instant timeoutsAndrey Mayorov
2015-12-11Merge branch 'siri/sasl/doc-editors/OTP-13000' into maintSiri Hansen
* siri/sasl/doc-editors/OTP-13000: sasl: Editorial changes
2015-12-11Update appups in kernel, stdlib and sasl for OTP-18.2Siri Hansen
2015-12-11correct the snmp app up fileZandra
2015-12-11ssl: Fix typosIngela Anderton Andin
2015-12-11Merge branch 'ia/ssl/windows-tests' into maintIngela Anderton Andin
* ia/ssl/windows-tests: ssl: Use test case time out instead ssl: Use spawn_executable
2015-12-11Merge branch 'ia/ssl/renegotiate-tests' into maintIngela Anderton Andin
* ia/ssl/renegotiate-tests: ssl: Add renegotiation exception
2015-12-11[inets] Correct broken linksLars Thorsen
2015-12-11[orber] Align documentation to DTDLars Thorsen
2015-12-11[inets] Align documentation to DTDLars Thorsen
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