Memory Management Programming Guide
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CS 403/503: Programming Languages
BNF for <expression> <expression> → identifier | number | CS 403 -<expression> | (<expression>) | <expression><operator><expression> Organization of Programming Languages <operator> → + | - | * | / Class 3 - August 30, 2001 Topics For Today Parse Tree Review of BNF (Chapter 2.1) Derivations and parse trees (Chapter 2.1) Binding time (Chapter 3.1) Object lifetime and storage slope * x + intercept management (Chapter 3.2) BNF Concept Review Another Parse Tree Terminal symbols: Actual items that are part of the language (0,1,+,-,*,/,etc.) Non-Terminal symbols: <expr>, <op>, etc. Rule/production: A single line of BNF Alternatives: Expressed with | Also: slope * x + intercept *: 0 or more occurrences +:1 or more occurrences 1 Binding Lifetimes • Binding lifetime: The period of time Def: A binding is an association, such between the creation and destruction of a as between an attribute and an entity, name-to-object binding • Object lifetime: The period of time or between an operation and a between the creation and destruction of symbol. an object • These don’t necessarily coincide Def: Binding time is the time at which a • EX. Reference parameters binding takes place. Possible binding times Object Lifetimes… 1. Language design time--e.g., bind operator …correspond to one of three principal symbols to operations 2. Language implementation time--e.g., bind fl. pt. storage allocation mechanisms: type to a representation Static objects: Object lifetime = program 3. Compile time--e.g., bind a variable to a type in C execution. Object bound to one storage or Java location from load time on. 4. Load time--e.g., bind a FORTRAN 77 variable to a memory cell (or a C static variable) Stack objects: Object lifetime = subroutine 5. -
Gnu Smalltalk Library Reference Version 3.2.5 24 November 2017
gnu Smalltalk Library Reference Version 3.2.5 24 November 2017 by Paolo Bonzini Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, with no Front-Cover Texts, and with no Back-Cover Texts. A copy of the license is included in the section entitled \GNU Free Documentation License". 1 3 1 Base classes 1.1 Tree Classes documented in this manual are boldfaced. Autoload Object Behavior ClassDescription Class Metaclass BlockClosure Boolean False True CObject CAggregate CArray CPtr CString CCallable CCallbackDescriptor CFunctionDescriptor CCompound CStruct CUnion CScalar CChar CDouble CFloat CInt CLong CLongDouble CLongLong CShort CSmalltalk CUChar CByte CBoolean CUInt CULong CULongLong CUShort ContextPart 4 GNU Smalltalk Library Reference BlockContext MethodContext Continuation CType CPtrCType CArrayCType CScalarCType CStringCType Delay Directory DLD DumperProxy AlternativeObjectProxy NullProxy VersionableObjectProxy PluggableProxy SingletonProxy DynamicVariable Exception Error ArithmeticError ZeroDivide MessageNotUnderstood SystemExceptions.InvalidValue SystemExceptions.EmptyCollection SystemExceptions.InvalidArgument SystemExceptions.AlreadyDefined SystemExceptions.ArgumentOutOfRange SystemExceptions.IndexOutOfRange SystemExceptions.InvalidSize SystemExceptions.NotFound SystemExceptions.PackageNotAvailable SystemExceptions.InvalidProcessState SystemExceptions.InvalidState -
Secure the Clones - Static Enforcement of Policies for Secure Object Copying Thomas Jensen, Florent Kirchner, David Pichardie
Secure the Clones - Static Enforcement of Policies for Secure Object Copying Thomas Jensen, Florent Kirchner, David Pichardie To cite this version: Thomas Jensen, Florent Kirchner, David Pichardie. Secure the Clones - Static Enforcement of Policies for Secure Object Copying. ESOP 2011, 2011, Saarbrucken, Germany. hal-01110817 HAL Id: hal-01110817 https://hal.inria.fr/hal-01110817 Submitted on 28 Jan 2015 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Secure the Clones * Static Enforcement of Policies for Secure Object Copying Thomas Jensen, Florent Kirchner, and David Pichardie INRIA Rennes – Bretagne Atlantique, France [email protected] Abstract. Exchanging mutable data objects with untrusted code is a delicate matter because of the risk of creating a data space that is accessible by an attacker. Consequently, secure programming guidelines for Java stress the importance of using defensive copying before accepting or handing out references to an inter- nal mutable object. However, implementation of a copy method (like clone()) is entirely left to the programmer. It may not provide a sufficiently deep copy of an object and is subject to overriding by a malicious sub-class. Currently no language-based mechanism supports secure object cloning. -
C++/CLI Language Specification
Ecma/TC39-TG5/2004/25 C++/CLI Language Specification Working Draft 1.5, Jun, 2004 Public Review Document Text highlighted like this indicates a placeholder for some future action. It might be a note from the editor to himself, or an indication of the actual or expected direction of some as-yet open issue. Note: In the spirit of the "Working Draft, Standard for Programming Language C++", this is an early draft. It’s known to be incomplet and incorrekt, and it has lots of bad formatting. Publication Time: 6/17/2004 11:44 PM Table of Contents Table of Contents Introduction....................................................................................................................................................xi 1. Scope............................................................................................................................................................. 1 2. Conformance ............................................................................................................................................... 2 3. Normative references .................................................................................................................................. 3 4. Definitions .................................................................................................................................................... 4 5. Notational conventions................................................................................................................................ 7 6. Acronyms and abbreviations -
Lazy Object Copy As a Platform for Population-Based Probabilistic Programming
Lazy object copy as a platform for population-based probabilistic programming Lawrence M. Murray Uber AI Abstract This work considers dynamic memory management for population-based probabilistic programs, such as those using particle methods for inference. Such programs exhibit a pattern of allocating, copying, potentially mutating, and deallocating collections of similar objects through successive generations. These objects may assemble data structures such as stacks, queues, lists, ragged arrays, and trees, which may be of random, and possibly unbounded, size. For the simple case of N particles, T generations, D objects, and resampling at each generation, dense representation requires O(DNT ) memory, while sparse representation requires only O(DT + DN log DN) memory, based on existing theoretical results. This work describes an object copy-on-write platform to automate this saving for the programmer. The core idea is formalized using labeled directed multigraphs, where vertices represent objects, edges the pointers between them, and labels the necessary bookkeeping. A specific labeling scheme is proposed for high performance under the motivating pattern. The platform is implemented for the Birch probabilistic programming language, using smart pointers, hash tables, and reference-counting garbage collection. It is tested empirically on a number of realistic probabilistic programs, and shown to significantly reduce memory use and execution time in a manner consistent with theoretical expectations. This enables copy-on-write for the imperative programmer, lazy deep copies for the object-oriented programmer, and in-place write optimizations for the functional programmer. 1 Introduction Probabilistic programming aims at better accommodating the workflow of probabilistic modeling and inference in general-purpose programming languages. -
Concurrent Copying Garbage Collection with Hardware Transactional Memory
Concurrent Copying Garbage Collection with Hardware Transactional Memory Zixian Cai 蔡子弦 A thesis submitted in partial fulfilment of the degree of Bachelor of Philosophy (Honours) at The Australian National University November 2020 © Zixian Cai 2020 Typeset in TeX Gyre Pagella, URW Classico, and DejaVu Sans Mono by XƎTEX and XƎLATEX. Except where otherwise indicated, this thesis is my own original work. Zixian Cai 12 November 2020 To 2020, what does not kill you makes you stronger. Acknowledgments First and foremost, I thank my shifu1, Steve Blackburn. When I asked you how to learn to do research, you said that it often takes the form of an apprenticeship. Indeed, you taught me the craft of research by example, demonstrating how to be a good teacher, a good researcher, and a good community leader. Apart from the vast technical ex- pertise, you have also been a constant source of advice, support, and encouragement throughout my undergraduate career. I could not ask for a better mentor. I thank Mike Bond from The Ohio State University, who co-supervises me. Meet- ings with you and Steve are always enjoyable for me. I am sorry for the meetings that went over time, often around the dinner time for you, lowering your glucose level. You help me turn complicated ideas into implementation with your experiences in hard- ware transactional memory. I am thankful for your patient guidance and inspiration. Many people have helped me with this thesis. I thank Adrian Herrera, Kunal Sa- reen, and Brenda Wang for subjecting themselves to the draft of this document, and providing valuable feedback. -
C# Programming in Depth Lecture 4: Garbage Collection & Exception
Chair of Software Engineering C# Programming in Depth Prof. Dr. Bertrand Meyer March 2007 – May 2007 Lecture 4: Garbage Collection & Exception Handling Lisa (Ling) Liu Overview Scope and lifetime Garbage collection mechanism Exception handling C# programming lecture 4: Garbage Collection & Exception Handling 2 Scope and lifetime Scope of a variable is portion of program text within which it is declared ¾ Need not be contiguous ¾ In C#, is static: independent of data Lifetime or extent of storage is portion of program execution during which it exists ¾ Always contiguous ¾ Generally dynamic: dependent on data Class of lifetime ¾ Static: entire duration of program ¾ Local or automatic: duration of call or block execution (local variable) ¾ Dynamic: From time of allocation statement (new) to deallocation, if any. C# programming lecture 4: Garbage Collection & Exception Handling 3 Object lifetime in C# Memory allocation for an object should be made using the “new” keyword Objects are allocated onto the managed heap, where they are automatically deallocated by the runtime at “some time in the future” Garbage collection is automated in C# Rule: Allocate an object onto the managed heap using the new keyword and forget about it C# programming lecture 4: Garbage Collection & Exception Handling 4 Object creation When a call to new is made, it creates a CIL “newobj” instruction to the code module public static int Main (string[] args) { Car c = new Car(“Viper”, 200, 100); } IL_000c: newobj instance void CilNew.Car::.ctor (string, int32, -
Obstacl: a Language with Objects, Subtyping, and Classes
OBSTACL: A LANGUAGE WITH OBJECTS, SUBTYPING, AND CLASSES A DISSERTATION SUBMITTED TO THE DEPARTMENT OF COMPUTER SCIENCE AND THE COMMITTEE ON GRADUATE STUDIES OF STANFORD UNIVERSITY IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY By Amit Jayant Patel December 2001 c Copyright 2002 by Amit Jayant Patel All Rights Reserved ii I certify that I have read this dissertation and that in my opin- ion it is fully adequate, in scope and quality, as a dissertation for the degree of Doctor of Philosophy. John Mitchell (Principal Adviser) I certify that I have read this dissertation and that in my opin- ion it is fully adequate, in scope and quality, as a dissertation for the degree of Doctor of Philosophy. Kathleen Fisher I certify that I have read this dissertation and that in my opin- ion it is fully adequate, in scope and quality, as a dissertation for the degree of Doctor of Philosophy. David Dill Approved for the University Committee on Graduate Studies: iii Abstract Widely used object-oriented programming languages such as C++ and Java support soft- ware engineering practices but do not have a clean theoretical foundation. On the other hand, most research languages with well-developed foundations are not designed to support software engineering practices. This thesis bridges the gap by presenting OBSTACL, an object-oriented extension of ML with a sound theoretical basis and features that lend themselves to efficient implementation. OBSTACL supports modular programming techniques with objects, classes, structural subtyping, and a modular object construction system. OBSTACL's parameterized inheritance mechanism can be used to express both single inheritance and most common uses of multiple inheritance. -
Lecture 8 EECS 498 Winter 2000
C++ Object Model Classes are abstract types. Objects are instances of that type. Three distinctive aspects of an OO System • Encapsulation Classes group related data and methods • Inheritance Derived classes extend and refine existing abstractions ... the design of consistent, intuitive, and useful class hierarchies is a complex and difficult art. • Dynamic Binding (polymorphism) Delay selection of appropriate abstraction implementation until program execution. ... OO programming is abstract data types with polymorphism C++ Object Model 1 of 19 Lecture 8 EECS 498 Winter 2000 Aspects to Examine • Distinctive Types of Programming • Semantics of Constructors • Semantics of Data • Semantics of Functions • Semantics of Construction, Destruction & Copy C++ Object Model 2 of 19 Lecture 8 EECS 498 Winter 2000 Distinctive Types of Programming • Procedural char *target, *source = “Hello World!”; target = malloc( strlen( source )); strcpy( target, source ); • Abstract Data Type String target, source = “Hello World!”; target = source; if (source == target) ... • Object Oriented class B { virtual int F(int) {return 1;} /* pure? /; } class D : B { virtual void F(int) { return 2;} } class E : B { virtual void F(int) { return 3;} } ... B *b = new B, B *d = new D, E *e = new D; cout << b->F() << d->F() << e->F() << endl; Object oriented model requires reference to operating object. Referred to as this (self, current, etc.) Often first parameter to function C++ Object Model 3 of 19 Lecture 8 EECS 498 Winter 2000 Storage Layout Procedural • Storage sizes are known at compile time Pointers have fixed size on target platform Data namespace encapsulated in type structure Function namespace global Abstract Data Types • Namespace for functions bound to data structure Signature of function is name, result type, parameter types Object Oriented • Virtual functions invocation structure Virtual base classes A virtual base class occurs exactly once in a derived class regardless of the number of times encountered in the class inheritance heirarchy. -
SECURE the CLONES 1. Introduction Exchanging Data Objects with Untrusted Code Is a Delicate Matter Because of the Risk of Creati
Logical Methods in Computer Science Vol. 8 (2:05) 2012, pp. 1–30 Submitted Sep. 17, 2011 www.lmcs-online.org Published May. 31, 2012 SECURE THE CLONES THOMAS JENSEN, FLORENT KIRCHNER, AND DAVID PICHARDIE INRIA Rennes { Bretagne Atlantique, France e-mail address: fi[email protected] Abstract. Exchanging mutable data objects with untrusted code is a delicate matter be- cause of the risk of creating a data space that is accessible by an attacker. Consequently, secure programming guidelines for Java stress the importance of using defensive copying before accepting or handing out references to an internal mutable object. However, im- plementation of a copy method (like clone()) is entirely left to the programmer. It may not provide a sufficiently deep copy of an object and is subject to overriding by a mali- cious sub-class. Currently no language-based mechanism supports secure object cloning. This paper proposes a type-based annotation system for defining modular copy policies for class-based object-oriented programs. A copy policy specifies the maximally allowed sharing between an object and its clone. We present a static enforcement mechanism that will guarantee that all classes fulfil their copy policy, even in the presence of overriding of copy methods, and establish the semantic correctness of the overall approach in Coq. The mechanism has been implemented and experimentally evaluated on clone methods from several Java libraries. 1. Introduction Exchanging data objects with untrusted code is a delicate matter because of the risk of creating a data space that is accessible by an attacker. Consequently, secure programming guidelines for Java such as those proposed by Sun [17] and CERT [6] stress the importance of using defensive copying or cloning before accepting or handing out references to an internal mutable object. -
Generating Object Lifetime Traces with Merlin
Generating Object Lifetime Traces with Merlin MATTHEW HERTZ University of Massachusetts, Amherst STEPHEN M BLACKBURN Australian National University J ELIOT B MOSS University of Massachusetts, Amherst KATHRYN S McKINLEY University of Texas at Austin and DARKO STEFANOVIC´ University of New Mexico ÈÖÓÖÑÑÖ× Ö ÛÖØÒ ÖÔÐÝ ÖÓÛÒ ÒÙÑ Ö Ó ÔÖÓÖÑ× Ò Ó Ø ÐÒÙ׸ × ÂÚ Ò ¸ ØØ ÖÕÙÖ Ö Ö Ò ×ÑÙÐØÓÒ ×Ô ÜÔÐÓÖØÓÒ ÙÔ Ý ÒÐÒ Ô Ö ÙÒÖרÒÒ× Ó Ó ÐØÑ ÚÓÖ Ò Ò ×Ò Ó ÒÛ Ö ÐÓÖØÑ׺ ÏÒ ÒÖØÒ Ô Ø ÖÙØ¹ÓÖ ÑØÓ Ó Ó ÐØÑ× ÖÕÙÖ× ÛÓÐ¹Ô Ö Ø ÚÖÝ Ô ÓØÒØÐ Ô ÓÒØ Ò Ø ÔÖÓÖѺ Ø× ÔÖÓ × ÔÖÓØÚÐÝ ÜÔ Ò×Ú¸ Ö× ÓØÒ ÒÙÐØ Ý ÓÒÐÝ Ô ÖÓ ¸ ºº¸ ÚÖÝ ¿¾Ã ÝØ× Ó ÐÐÓ Ù× Ö Û Ï ÜØÒ Ø ×ØØ Ó Ø ÖØ ÓÖ ×ÑÙÐØÒ Ö ÐÓÖØÑ× Ò ØÛÓÛÝ׺ Öר¸ ÚÐÓÔ ÑØÓ ÓÐÓÝ ÓÖ ×ÑÙÐØÓÒ ×ØÙ× Ó ÝÒ Ö Ò ÔÖ×ÒØ Ö×ÙÐØ× ×ÓÛÒ Ø Ó ÖÒÙÐÖØÝ ÓÒ Ø× ×ÑÙÐØÓÒ׺ Ï ×ÓÛ ØØ ÖÒÙÐÖØÝ ÓØÒ ×ØÓÖØ× ×ÑÙÐØ Ö Ö×ÙÐØ× ÛØ Ô Û ÓÖ Ó ÔÖ×ÒØ Ò Ñ×ÙÖ Ø Ô Ó ÒÛ ÐÓÖØÑ ÅÖÐÒ ÐØÑ׺ ÅÖÐÒ ØÑרÑÔ× Ó Ò ÐØÖ Ù×× Ø ØÑרÑÔ× Ó Ó ØÓ ÛÒ ØÝ º Ì ÅÖÐÒ ÐÓÖØÑ × ÓÒ Ö Ô ÖÓÖÑ Ý Ø × ÖÑÒØÐ Ö×ÙÐØ× ×ÓÛ ØØ ÅÖÐÒ ÒÖØ ÓÚÖ ØÛÓ ÓÖÖ× Ó ÑÒØÙ ×Ý×ØÑº ÜÔ ×ØÖ ØÒ Ø ÑØÓ ØÖ ÚÖÝ Ó ÐÐÓ Ï Ð×Ó Ù× ÅÖÐÒ ØÓ ÔÖÓ Ú×ÙÐÞØÓÒ× Ó Ô ÚÓÖ ØØ ÜÔ Ó× ÒÛ Ó ÐØÑ ÚÓÖ׺ Categories and Subject Descriptors: D.3.4 [Programming Languages]: Processors—memory management (gar- bage collection) ÒÖÐ ÌÖÑ× ÐÓÖØÑ׸ ÄÒÙ׸ È ØÓÒÐ ÃÝ ÏÓÖ× Ò ÈÖ×× Ö ×Ò¸ Ó ÐØÑ ÒÐÝ×׸ ÒÖØÓÒ This work is supported by NSF grants CCR-0219587, ITR CCR-0085792, EIA-0218262, EIA-9726401, EIA- 030609, EIA-0238027, EIA-0324845, DARPA F33615-03-C-4106, Hewlett-Packard gift 88425.1, Microsoft Re- search, and IBM. -
Modern C++ Object-Oriented Programming
CPP Modern C++ Object-Oriented Programming ''Combine old and newer features to get the best out of the language'' Margit ANTAL 2020 C++ - Object-Oriented Programming Course content − Introduction to C++ − Object-oriented programming − Generic programming and the STL − Object-oriented design C++ - Object-Oriented Programming References − Bjarne Stroustrup, Herb Sutter, C++ Core Guidelines, 2017. rd − M. Gregoire, Professional C++, 3 edition, John Wiley & Sons, 2014. th − S. Lippman, J. Lajoie, B. E. Moo, C++ Primer, 5 edition, Addison Wesley, , 2013. th − S. Prata, C++ Primer Plus, 6 edition, Addison Wesley, 2012. − N. Josuttis, The C++ standard library. a tutorial and reference. Pearson Education. 2012. − A. Williams, C++ Concurrency in Action:Practical Multithreading. Greenwich, CT: Manning. 2012. Module 1 Introduction to C++ Introduction to C++ Content − History and evolution − Overview of the key features ● New built-in types ● Scope and namespaces ● Enumerations ● Dynamic memory: new and delete ● Smart pointers: unique_ptr, shared_ptr, weak_ptr ● Error handling with exceptions ● References ● The const modifier Introduction to C++ History and evolution − Creator: Bjarne Stroustrup 1983 − Standards: ● The first C++ standard − 1998 (C++98, major) − 2003 (C++03, minor) ● The second C++ standard − 2011 (C++11, major) – significant improvements in language and library − 2014 (C++14, minor) − 2017 (C++17, major) Introduction to C+ History and evolution − source: https://isocpp.org/std/status Introduction to C+ History and evolution − source: