Semantic dictionary encoding (SDE) preserves the full semantic context of source programs while adding further information that can be used for accelerating the speed of
code generation. SDE forms a code-generating loader. It is a form of
bytecode
Bytecode (also called portable code or p-code) is a form of instruction set designed for efficient execution by a software interpreter. Unlike human-readable source code, bytecodes are compact numeric codes, constants, and references (normal ...
combined with a
JIT compiler
In computing, just-in-time (JIT) compilation (also dynamic translation or run-time compilations) is compiler, compilation (of Source code, computer code) during execution of a program (at run time (program lifecycle phase), run time) rather than b ...
. It is code generation at load time.
In an elementary form, the dictionary entries represent nodes in a
directed acyclic graph
In mathematics, particularly graph theory, and computer science, a directed acyclic graph (DAG) is a directed graph with no directed cycles. That is, it consists of vertices and edges (also called ''arcs''), with each edge directed from one ...
(DAG), that describes the actions of the program, as an
abstract syntax tree
An abstract syntax tree (AST) is a data structure used in computer science to represent the structure of a program or code snippet. It is a tree representation of the abstract syntactic structure of text (often source code) written in a formal ...
(AST) in tabular form.
It uses an
intermediate representation
An intermediate representation (IR) is the data structure or code used internally by a compiler or virtual machine to represent source code. An IR is designed to be conducive to further processing, such as optimization and translation. A "good" ...
(IR), that is based on the encoded abstract syntax tree and
symbol table
In computer science, a symbol table is a data structure used by a language translator such as a compiler or interpreter, where each identifier, symbol, constant, procedure and function in a program's source code is associated with information ...
of a program.
See also
*
Semantics encoding {{unreferenced, date=March 2017
A semantics encoding is a translation between formal languages. For programmers, the most familiar form of encoding is the compilation of a programming language into machine code or byte-code. Conversion between docu ...
*
Code generation
*
Software portability
Software consists of computer programs that instruct the execution of a computer. Software also includes design documents and specifications.
The history of software is closely tied to the development of digital computers in the mid-20th ...
References
External links
A brief introduction to Semantic Dictionary Encoding*
Intermediate representations of mobile code
Compiler construction
Semantics
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