Changeset 9c8afc7

Timestamp:

Dec 3, 2025, 3:04:18 PM (23 hours ago)

Author:

Peter A. Buhr <pabuhr@…>

Branches:

master

Parents:

00aa122

Message:

proofread abstract

File:

• doc/theses/mike_brooks_MMath/uw-ethesis-frontpgs.tex (modified) (1 diff)

doc/theses/mike_brooks_MMath/uw-ethesis-frontpgs.tex

@@ -129 +129 @@
 \begin{center}\textbf{Abstract}\end{center}
 
+\CFA strives to fix mistakes in C, chief among them, safety.
+This thesis presents a significant step forward in \CFA's goal to remove unsafe pointer operations.
+The thesis presents improvements to the \CFA language design, both syntax and semantics, to support advanced container features.
+These features are implemented across the \CFA compiler, libraries, and runtime system.
+The results maintain another \CFA goal of remaining 99\% backwards compatible with C.
+This thesis leverages preexisting work within the compiler's type and runtime systems generated by prior students working on the \CFA project.
+
 All modern programming languages provide three high-level containers (collections): array, linked-list, and string.
-Often array is part of the programming language, while linked-list is built from (recursive) pointer types, and string from a combination of array and linked-list.
+Often array is part of the programming language, while linked-lists are built from (recursive) pointer types, and strings from a combination of array and linked-list.
 For all three types, languages and/or their libraries supply varying degrees of high-level mechanisms for manipulating these objects at the bulk and component level, such as copying, slicing, extracting, and iterating among elements.
-Unfortunately, these three aspects of C cause 60\%--70\% of the reported software vulnerabilities involved memory errors, and 70\%--80\% of hacker attack-vectors target these types.
+Unfortunately, these three aspects of C cause 60\%--70\% of the reported software vulnerabilities involving memory errors, and 70\%--80\% of hacker attack-vectors target these types.
 Therefore, hardening these three C types goes a long way to make the majority of C programs safer.
 
-This work looks at extending these three foundational container types in the programming language \CFA, which is a new dialect of the C programming language.
-The thesis describes improvements made to the \CFA language design, both syntax and semantics, to support the container features, and the source code created within the \CFA compiler, libraries, and runtime system to implement these features.
-This work leverages preexisting work within the compiler's type and runtime systems generated by prior students working on the \CFA project.
-
-Overall, this work has produced significant syntactic and semantic improvements to C's container types.
-\begin{enumerate}[leftmargin=*]
-\item
-Introduce a small number of subtle changes to the typing rules for the C array, while still achieving significant backwards compatibility.
-\item
-Create a new polymorphic mechanism in the \CFA @forall@ clause to specify array dimension values, similar to a fixed-typed parameter in a \CC \lstinline[language=C++]{template}.
-The new array type, enabled by prior features, defines an array with guaranteed runtime bound checks (often optimizer-removable) and implicit (guaranteed accurate) inter-function length communication.
-\item
-Create a new polymorphic list type and its runtime library following the established design pattern of intrusive link-fields for performance reasons, especially in concurrent programs.
-\item
-Create a new string type and runtime library comparable to the \CC @string@ type, including analogous coexistence with raw-character pointers, enabling programs to work with strings by value, without incurring excessive copying.
-Substrings are supported, including the ability for overlapping ranges to share edits transparently.
-\end{enumerate}
-The thesis includes a performance evaluation that shows the new \CFA containers perform comparably with their C counterparts in many programming cases.
+Specifically, an array utility is provided that tracks length internally, relieving the user of managing explicit length parameters and stopping buffer-overrun errors.
+This feature requires augmenting the \CFA type system, making array length available at compile and runtime.
+A linked-list utility is provided, which obviates many explicit recursive pointers by catering directly to system-programming uses (intrusive lists) for which a library solution is often dismissed.
+Finally, a string utility is provided with implicit memory management of text in a specialized heap, relieving error-prone buffer management, including overrun, and providing a copy-on-write speed boost.
+For all three utilities, performance is argued to be on-par with, and occasionally surpassing relevant comparators.
+With the array, this case is made by showing complete erasure down to a naked C array, modulo runtime bound checks, which are removable more often than with Java-style length management.
+With the linked list and string, empirical measures are compared with relevant libraries.
+These utilities offer a system programmer workable alternatives to hand-rolling several common causes of system vulnerabilities, thereby improving \CFA's position as a safety-forward system-programming alternative.
 
 \cleardoublepage