reversing

C Function

A block of code that takes inputs (parameters), performs a logical operation, and returns an output.

GCC (GNU C Compiler)

A compiler used to translate C code into executable machine code, involving stages like compiling, assembling, and linking.

Assembly Language

A low-level programming language that provides direct control over hardware with less abstraction, potentially enabling faster code.

Registers

Small, fast storage locations within a CPU used to quickly hold and manipulate data, typically 32-bit in size for x86-64 architecture.

Endianness

The way multi-byte data is stored in memory, specifically defining the order of bytes (most significant or least significant) within a word.

Big Endian

A storage order where the most significant byte of a multi-byte word is stored at the lowest memory address. Commonly used in networking.

Little Endian

A storage order where the least significant byte of a multi-byte word is stored at the lowest memory address. Commonly used by many processors.

MOV Dest, Source

An x86-64 assembly instruction that performs a move operation, copying data from the Source to the Destination.

ADD Dest, Source

An x86-64 assembly instruction that adds the Source value to the Destination and stores the result in the Destination.

Abstraction vs. Performance Trade-off

The principle that higher-level languages enhance productivity and abstract away details (like memory management), while lower-level languages offer more control and potential for optimization, but at the cost of complexity.

Compiler

A program that translates high-level code (like C) into a lower-level representation, eventually becoming machine code.

Assembly Label

An optional, programmer-chosen name for a statement in assembly code, used for control flow (e.g., with JMP instructions).

Return Type (C Function)

The data type of the value that a function sends back as its output.