Test: Lexical Analysis- 1 - Computer Science Engineering (CSE) MCQ

The code optimization phase [i.e. machine independent optimization] attempts to improve the intermediate code, so that faster-running machine code will result.
Hence, it is associated with the creation of more optimal matrix.

In 2-pass assembler during pass-1 pseudo code EQU is to be evaluated.

Operation performed during pass-1 in 2-pass compiler:
1. Processing the DB pseudo-op.
2. Updating the location counter.
3. Processing of EQU pseudo-op.
4. Processing of DS pseudo-op.

Lexical analysis consists of the phases that
(i) Simplify the subsequent phases by the help of tokens instead of arbitrary elements.
(ii) Since interrelated elements are converted to stream of tokens hence compiler efficiency is improved as no arbitrary storage or value is to be checked independently.
(iii) Computer portability is enhanced.

Error is underlined function fro()
Which is a syntactical error rather than lexical.

Hash table can contribute to an efficient average case solution for symbol table look up problem

The final phase of the compiler is the generation of target code, consisting of relocatable machine code or assembly code. Intermediate instruction are each translated into a sequence of machine instructions that perform the same task. A crucial aspect is the assignment of variables to registers.

In analysing the compilation of PL/I program the description "creation of more optimal matrix” is associated with machine independent optimization.

The main task of lexical analyser is to read the input characters and producers as output  sequence of tokens that the parser uses for syntax analysis.

Translator is a system software. Generally, it comes with the operating system.

Resolution is generally done during linking. Hence, linker does this

Simple two-pass assembler:
1. Allocates space for the literals.
2. Computers the total length of program (syntax analysis).
3. Builds the symbol table for the symbols and their values.

A compiler is a software program that accepts a program written in a high level language and generate object code.

A loader is a program that place programs into memory and prepare them for execution.

There are three types of language processors:

• Assembler
• Interpreter
• Compiler