The 'shift' action in an LR parser moves the next input symbol onto the stack and transitions to a new state.

A token is a data structure that represents a keyword, identifier, or other meaningful element in the source code.

The 'shift' action in LR parsing moves the input pointer to the next token.

An attribute represents a semantic value associated with a grammar symbol in syntax-directed translation.

Intermediate code is a representation that is easier to optimize than the original source code.

Semantic actions in syntax-directed translation are used to generate intermediate code based on the parse tree.

Synthesized attributes are computed from the attributes of the child nodes in syntax-directed translation.

The '1' in LL(1) indicates that one lookahead token is used to make parsing decisions.

Three-address code represents binary operations in the form 'result = operand1 operator operand2', which clearly indicates the result of the operation.

Three-address code typically allows for at most three operands: two source operands and one destination operand.

Common subexpression elimination achieves the elimination of duplicate calculations, thus optimizing the code.

Dead code elimination refers to removing code that is never executed, which can help reduce the size of the code.

LR parsing stands for Left-to-right parsing with a rightmost derivation in reverse.

The 'reduce' action in an LR parser pops a number of symbols from the stack and replaces them with a non-terminal according to a production rule.

Grammar ambiguity refers to the situation where multiple valid parse trees can be generated for a single input string.

Register allocation refers to the process of assigning variables to CPU registers to optimize access speed.

A symbol table is a data structure that stores information about identifiers, such as their types and scopes.

In lexical analysis, a token refers to a meaningful sequence of characters that represents a basic element of the language.

A lexeme is the actual sequence of characters in the source code that matches a token.

A lexeme is a sequence of characters in the source code that matches a token defined by the lexical analyzer.

A common application of syntax-directed translation in compilers is semantic analysis.

Intermediate code is generally easier to analyze than high-level code due to its simpler structure and reduced abstraction.

LL parsers cannot handle ambiguous grammars, which limits their applicability.

All of the listed techniques can be applied during the optimization phase of intermediate code generation to improve performance.

Intermediate code is an abstract representation of the program that is independent of the target machine, allowing for easier optimization and code generation.

Loop unrolling is a method to reduce the overhead of loop control by increasing the number of operations performed in each iteration.

An abstract syntax tree (AST) provides a hierarchical representation of the program structure, making it easier to apply optimizations compared to linear representations.

The main advantage of using syntax-directed translation is that it allows for easy integration of semantic analysis.

The main challenge of optimizing code for different architectures is the varying instruction sets and performance characteristics.

LL parsing is a top-down parsing technique that processes the input from left to right and constructs a leftmost derivation of the sentence.