Deck 11: Compilers and Language Translation

Question 1

High-level languages must be translated into hybrid language before they can be executed. _________________________

Answer 1

False
machine

Question 2

Performing local optimization is much more difficult than performing global optimization.

Answer 2

False

Question 3

____________________ for high-level languages like C++ or Java are very large.

Answer 3

Grammars

Question 4

One of the possible local ____________________ is eliminating unnecessary operations.

Question 5

The goal symbol is the final nonterminal.

Question 6

The output of a parser is a(n) complete ____________________, or an error message if one cannot be constructed.

Question 7

A BNF rule is also known as a production.

Question 8

Parsing is the first phase of the compilation process. _________________________

Question 9

A high-level language statement is translated into a single machine language instruction.

Question 10

The English-language sentence, "The orange artichoke flew through the elephant" is semantically meaningful. _________________________

Question 11

The singular goal of compilers is correctness.

Question 12

The input to a scanner is the machine language statement from the source program.

Question 13

A grammar that allows the construction of two or more distinct parse trees for the same statement is called a recursive grammar.

Question 14

The righthand side of a BNF rule is the name of a single grammatical category.

Question 15

Building two parse trees implies that the parser has demonstrated correctness in two different ways. _________________________

Question 16

Online debuggers help programmers locate and correct errors in programs.

Question 17

The output of a(n) ____________________ is a list of all the tokens contained in a high-level language statement, as well as the classification number of each token found.

Question 18

If a parser can convert the sequence of input tokens into the goal symbol, then that sequence of tokens is a syntactically ____________________ statement of the language.

Question 19

In BNF, the syntax of a language is specified as a series of grammars. _________________________

Question 20

The code a compiler produces should be reasonably efficient and concise.

Question 21

A(n) ____ is a compiler embedded with a collection of supporting software.

A) debugger
B) reusable code library
C) visual development library
D) integrated development environment

Question 22

A ____ shows how individual tokens can be grouped into predefined grammatical categories until the desired goal is reached.

A) parse tree
B) scanner
C) parser
D) compiler

Question 23

A high-level language program is called a(n) ____ program.

A) object
B) source
C) lexical
D) token

Question 24

____ is where the compiler polishes and fine-tunes the translation so that it runs a little faster or occupies a little less memory.

A) Compilation
B) Generation
C) Optimization
D) Efficiency

Question 25

In the ____ phase, the compiler takes the generated code and sees whether it can be made more efficient, either by making it run faster or having it occupy less memory.

A) code optimization
B) parsing
C) lexical analysis
D) semantic analysis and code generation

Question 26

____ is the replacement of slow arithmetic operations with faster ones.

A) Strength reduction
B) Constant evaluation
C) Eliminating unnecessary operations
D) Parse tree construction

Question 27

____ begins at the productions in the tree that are nearest to the original input tokens.

A) Code generation
B) Parsing
C) Lexical analysis
D) Semantic analysis

Question 28

Following ____, the compiler makes a second pass over the parse tree to produce the translated code.

A) semantic analysis
B) lexical analysis
C) code optimization
D) code generation

Question 29

The Greek character lambda represents ___.

A) zero
B) the null string
C) the defined string
D) the unknown string

Question 30

____ is the ability to write highly optimized programs that contain no wasted time or unnecessary memory cells.

A) Conciseness
B) Ambiguity
C) Code-aware
D) Efficiency

Question 31

In ____ optimization, the compiler looks at large segments of the program to decide how to improve performance.

A) local
B) global
C) semantic
D) syntactical

Question 32

In BNF, a ____ is an intermediate grammatical category used to help explain and organize the language.

A) production
B) rule
C) terminal
D) nonterminal

Question 33

During the ____ phase, the sequence of tokens formed by the scanner is checked to see whether it is syntactically correct according to the rules of the programming language.

A) lexical analysis
B) parsing
C) code optimization
D) semantic analysis and code generation

Question 34

In the ____ phase, the compiler examines the individual characters in the source program and groups them into tokens.

A) semantic analysis and code generation
B) parsing
C) lexical analysis
D) code optimization

Question 35

During parsing, a compiler deals only with the ____ of a statement.

A) semantics
B) syntax
C) grammar
D) rules

Question 36

A ____ is a data structure that stores information about a nonterminal, such as the actual name of the object and its data type.

A) rule
B) production
C) parse tree
D) semantic record

Question 37

In BNF, the ____ is used to separate two alternative definitions of a nonterminal.

A) forward slash
B) vertical bar
C) backward slash
D) asterisk

Question 38

____ parsing algorithms examine several tokens "down the road" to see what would happen if a certain choice was made.

A) Look-ahead
B) Token prediction
C) Down-the-road
D) Recursive

Question 39

The collection of all statements that can be successfully parsed is called the ____ defined by a grammar.

A) language
B) terminal
C) nonterminal
D) rule

Question 40

A(n) ____ definition defines a nonterminal symbol in terms of itself.

A) ambiguous
B) recursive
C) local
D) global

Question 41

If a parser is analyzing a statement in a language and it sees exactly the same sequence of objects that appears on the right-hand side of a BNF rule, what is it allowed to do?

Question 42

Explain what metasymbols are and discuss their use as part of BNF rules.

Question 43

What are the four phases of compilation?

Question 44

Explain what the goal in compiler design today is.

Question 45

List three possible local optimizations.

Question 46

What does this BNF rule say?
::= +

Question 47

Explain what the goal symbol is, and explain what its significance is.

Question 48

Regardless of which programming language is being analyzed, every scanner performs virtually the same set of operations. What are they?

Question 49

Present what each individual BNF rule looks like, and briefly explain its components.

Question 50

What is the fundamental rule of parsing?