The computer is an intelligent combination of software and hardware. Hardware is simply a piece of mechanical equipment and its functions are being compiled by the relevant software. The hardware considers instructions as electronic charge, which is equivalent to the binary language in software programming. The binary language has only 0s and 1s. To enlighten, the hardware code has to be written in binary format, which is just a series of 0s and 1s. Writing such code would be an inconvenient and complicated task for computer programmers, so we write programs in a high-level language, which is Convenient for us to comprehend and memorize. These programs are then fed into a series of devices and operating system (OS) components to obtain the desired code that can be used by the machine. This is known as a language processing system.

1. NAME- SOUMA MAITI
ROLL NO.- 27500120016
DEPARTMENT- COMPUTER SCIENCE
YEAR- 3RD YEAR (5TH SEMESTER)
SUBJECT NAME- COMPILER DESIGN
SUBJECT CODE- PCC-CS501
FACULTY INCHARGE-INDRANI
MUKHERJEE

2. INTRODUCTION TO COMPILER
 The Compiler is software that converts a program written in a
high-level language (Source Language) to a low-level language
(Object/Target/Machine Language/0’s, 1’s).

3. LANGUAGE PROCESSING SYSTEMS
(USING COMPILER):
 High-Level Language: If a program contains #define or #include
directives such as #include or #define it is called HLL. They are closer
to humans but far from machines. These (#) tags are called pre-
processor directives. They direct the pre-processor about what to do.
 Pre-Processor: he pre-processor removes all the #include directives
by including the files called file inclusion
 Assembly Language: It’s neither in binary form nor high level. It is an
intermediate state that is a combination of machine instructions and
some other useful data needed for execution.
 Assembler: Its translates assembly language to machine code. The
output of the assembler is called an object file
 Loader/Linker: It converts the relocatable code into absolute code
and tries to run the program resulting in a running program or an
error message. Linker loads a variety of object files into a single file to
make it executable. Then loader loads it in memory and executes it.

4. PHASES OF COMPILER
 There are two major phases of compilation:
 Analysis Phase: An intermediate representation is created from the given
source code :
1. Lexical Analyzer
2. Syntax Analyzer
3. Semantic Analyzer
4. Intermediate Code Generator
 Synthesis Phase: Equivalent target program is created from the intermediate
representation. It has two parts :
1. Code Optimizer
2. Code Generator
 Code Optimizer optimizes the abstract code, and the final Code Generator
translates abstract intermediate code into specific machine instructions.