CS2013-final-report

solutions to truly hard problems, such as instruction scheduling; the problems are designed to have a high ratio of
thought to programming.
Body of Knowledge coverage
KA Knowledge Unit Topics Covered Hours
AL
Basic Automata
Computability and
Complexity
Finite state machines, regular expressions, and context-free grammars 2
AL
Advanced
Automata
Theory and
Computability
DFA & NFAs (Thompson’s construction, the subset construction,
Hopcroft’s DFA minimization algorithm, Brzozowski’s DFA minimization
algorithm), regular expressions, context-free grammars (designing CFGs
and parsing them — recursive descent, LL(1), and LR(1) techniques
3
PL
Program
Representation
Syntax trees, abstract syntax trees, linear forms (3 address code), plus
lexically scoped symbol tables
2
PL
Language
Translation &
Execution
Interpretation, compilation, representations of procedures, methods, and
objects, memory layout (stack, heap, static),
Automatic collection versus manual deallocation
4
PL Syntax Analysis Scanner construction
Parsing: top-down recursive descent parsers, LL(1) parsers and parser
generators, LR(1) parsers and parser generators
6
PL
Compiler Semantic
Analysis
Construction of intermediate representations, simple type checking, lexical
scoping, binding, name resolutions; attribute grammar terms, evaluation
techniques, and strengths and weaknesses
3
PL Code Generation How to implement specific programming language constructs, as well as
algorithms for instruction selection (both tree pattern matching and
peephole-based schemes),
Instruction scheduling, register allocation
6
Other comments
The undergraduate compiler course provides an important opportunity to address three of the expected
characteristics of Computer Science graduates:
Appreciation of the Interplay Between Theory and Practice: The automation of scanners and parsers is one of the
best examples of theory put into practical application. Ideas developed in the 1960s became commonplace tools in
the 1970s. The same basic ideas and tools are (still) in widespread use in the 2010’s.
At the same time, compilers routinely compute and use approximate solutions to intractable problems, such as
instruction scheduling and register allocation which are NP-complete in almost any realistic formulation, or
constant propagation which runs into computability issues in its more general forms. In theory classes, students
learn to discern the difference between the tractable and the intractable; in a good compiler class, they learn to
approximate the solution to these problems and to use the results of such approximations.
System-level Perspective: The compiler course enhances the students’ understanding of systems in two quite
different ways. As part of learning to implement procedure calls, students come to understand how an agreement
on system-wide linkage conventions creates the necessary conditions for interoperability between application code
and system code and for code written in different languages and compiled with different compilers. In many ways,
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