An interactive guide to x86-64 assembly
This interactive guide explains x86-64 assembly, focusing on data movement, endianness, stack manipulation, memory alignment, and stack growth direction. It includes examples and reading suggestions for deeper understanding.
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This article serves as an interactive guide to x86-64 assembly, focusing on moving data within memory. It explains the mov instruction, which transfers data between registers, memory, and vice versa. The concept of endianness is discussed, highlighting how numbers are stored in memory in a reversed order. The article also covers stack manipulation using push and pop instructions, illustrating how the stack pointer rsp moves when elements are added or removed. Memory alignment is explained, emphasizing the importance of aligning data on 8-byte boundaries for performance reasons. The article provides an interactive example showcasing memory visualization and addresses the confusion that can arise due to the stack growing towards lower memory addresses. It also offers further reading suggestions for those interested in delving deeper into x86-64 assembly.
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3 commentsFunny trivia: while the Arabs wrote the numbers exactly as we do, they actually wrote them in the opposite order, the least significant digit first, and continued in ascending order, because Arabic script is actually written right-to-left. We the Europeans borrowed the notation as it looked when finished being written, so it had the unfortunate side effect of switching to the unnatural big-endian order.
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