Compiler Design and Analysis Overview

A type of grammar where the attributes can be computed directly from the syntax tree in a left-to-right, depth-first traversal.

A type of grammar where the attributes of a non-terminal can be computed from the attributes of its children.

Intermediate code that uses at most three addresses, including the left-hand side.

A representation of an expression that uses a directed acyclic graph (DAG) to represent common subexpressions.

A code optimization technique that ensures each variable is assigned a value only once.

The process of finding the minimum number of variables required to represent a given expression.

A technique used to determine the order of evaluation for a compound expression.

The method used to evaluate expressions in a left-to-right, depth-first manner, starting with the outermost nodes of the parse tree.

A sequence of characters used to represent text or code. For example, "Hello, world!" is a string.

A technique used to transform a grammar into an equivalent grammar that does not have left recursion. This helps avoid infinite loops in parsing.

A process of transforming a grammar into an equivalent grammar where common prefixes are factored out. Helps reduce ambiguity in parsing.

A type of parsing table used in compiler construction. It maps a non-terminal symbol and a lookahead terminal to the production to be used.

The set of terminals that can potentially appear as the first symbol in a derivation of a non-terminal.

The set of terminals that can potentially appear immediately after a non-terminal in a string derived by the grammar.

A process of constructing a parsing table for a grammar. The table maps each non-terminal and lookahead terminal to a production or an error.

A parsing technique where the parser starts from the start symbol of the grammar and derives the input string step-by-step using the productions of the grammar.

A sequence of instructions in a program where control enters only from the first statement (called the leader) and leaves only from the last statement.

A graphical representation of the control flow of a program. It consists of nodes that represent basic blocks and edges that represent the flow of control between blocks.

A technique that replaces expensive or complex operations with cheaper or simpler ones to improve the efficiency of code.

An optimization technique that removes unused or redundant code from a program. This code is called "dead code" and can be safely removed without affecting the program's behavior.

A technique that replaces repeated computations of the same expression with a single computation and reusing the result. This is done to avoid redundant calculations and improve efficiency.

A technique that improves the performance of loops by optimizing the way they are executed. Example techniques include loop unrolling and loop invariant code motion.

A technique that examines and optimizes small sequences of instructions within a program to improve their efficiency.

A technique that simplifies expressions by evaluating constant values at compile time.

A representation of a program that is easier for a computer to understand and manipulate. This representation can be used for analysis, optimization, and code generation.

A process where the compiler evaluates an expression in a program and determines its value. This is done by following the operator precedence and associativity rules.

Converting an infix expression, where the operator appears between the operands, to either prefix or postfix notation, where the operator appears before or after its operands, respectively.

An attribute whose value at a node in a parse tree is computed based on the attributes of its parent or siblings. The computation depends on the context within the tree.

An attribute whose value at a node in a parse tree is computed based on the attributes of its children. The computation depends on the values of the subtrees.

A formal description of how to associate attributes with a grammar and how to compute their values. It is used to define the semantics of a programming language and guide the compiler's analysis and code generation.

A grammar is considered ambiguous if a single sentential form can be derived by multiple parse trees. In essence, there is no single, clear way to interpret the structure of the sentence, making it difficult for a compiler to understand the intended meaning.

A grammar is called useless when it contains symbols that are unreachable or unproductive. Unreachable symbols cannot be derived from the start symbol, while unproductive symbols cannot derive any terminal string.

Bottom-up parsing is a parsing technique that begins with the input string and tries to construct the parse tree by incrementally building larger and larger syntactic units based on the grammar rules.

A parser is a program that analyzes the structure of a given string of symbols, typically in the form of a program or a sentence, to determine if it conforms to the rules of a specified grammar.

A parse tree is a hierarchical representation of the syntactic structure of a sentential form, according to the rules of a specific grammar. It illustrates the breakdown of the sentence into its constituent parts.

A deterministic push-down automaton (DPDA) is a finite automata extended with a stack memory. It reads input symbols and uses the stack to keep track of its state and make decisions. DPDAs play a crucial role in parsing, recognizing context-free languages.

LL(1) parsing is a top-down parsing technique where the parser predicts the next token based on a single lookahead symbol.

A method to determine if a grammar is LL(1) without constructing a parsing table. It involves checking for intersections between the first sets of different production alternatives of the grammar.

A type of parser that works bottom-up, building the parse tree from the leaves up to the root. It uses Reverse Polish Notation (RPN) and can handle left recursion and common prefixes in grammars.

A type of parser that uses LR(0) and adds one lookahead symbol to determine the next action. It can handle more grammars than LR(0).

A type of LR parser that builds a table of actions based on LR(0) items with lookahead symbols added for additional parsing power.

A type of LR parser that uses a single lookahead token to decide between different actions. It is a simple and efficient parser.

A type of parser that works by reducing the input string to a sentential form using productions. It starts with a single production and constructs the parse tree from the root downwards.

A type of LR parser that uses a single lookahead symbol to guide parsing decisions. It is less powerful than LR(1) but still handles a wide range of grammars.

An algorithm used in the construction of LR parsers involves augmenting the grammar, giving unique numbers to productions, constructing LR(0) or LR(1) item sets, and then filling the parsing table accordingly.