List various phases of a language processor. Explain roles of phases of LanguageProcessor

A language processor is a software that bridges the gap between the human language and machine language. It translates the source code into machine code so that a computer can understand and execute it. The language processor consists of several phases, each with a specific role. Here are the various phases of a language processor:

1. Lexical Analysis: This is the first phase of a language processor. The lexical analyzer reads the source program character by character, grouping them into meaningful sequences called lexemes, and then converts these lexemes into tokens. Tokens are the smallest units of a program, like keywords, identifiers, operators, and delimiters.

2. Syntax Analysis: This phase, also known as parsing, takes the tokens produced during the lexical analysis and generates a parse tree (or syntax tree) based on the grammatical structure of the source code. It checks the tokens for syntactical errors and confirms that they follow the rules of the programming language.

3. Semantic Analysis: This phase uses the syntax tree and the symbol table to check the source program for semantic consistency with the language definition. It checks for type mismatches, undeclared variables, etc. It also generates intermediate code.

4. Intermediate Code Generation: After semantic analysis, the source code is converted into an intermediate code that can be easily translated into the target machine code.

5. Code Optimization: This phase attempts to improve the intermediate code so that the final program runs faster and takes less space. It removes unnecessary codes, arranges the sequence of statements, etc.

6. Code Generation: This is the final phase of a language processor. The optimized intermediate code is translated into the target machine code. It allocates memory for variables and generates actual machine code.

7. Symbol Table Management: This is not a phase but an important part of a language processor. The symbol table is a data structure used by the compiler to keep track of semantics of variable i.e., properties like type of variable, scope of variable etc.

Each phase of the language processor plays a crucial role in translating human-readable source code into machine code that can be executed by a computer.