assembly Archives - IT Nursery

I’ve been contemplating how to protect my C/C++ code from disassembly and reverse engineering. Normally I would never condone this behavior myself in ...

May 28, 2022
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performance, Programming

IT Nursery

Why would introducing useless MOV instructions speed up a tight loop in x86_64 assembly?

Background: While optimizing some Pascal code with embedded assembly language, I noticed an unnecessary MOV instruction, and removed it. To my surprise, removing ...

May 26, 2022
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Why does GCC use multiplication by a strange number in implementing integer division?

I’ve been reading about div and mul assembly operations, and I decided to see them in action by writing a simple program in ...

May 22, 2022
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What is exactly the base pointer and stack pointer? To what do they point?

Using this example coming from wikipedia, in which DrawSquare() calls DrawLine(), (Note that this diagram has high addresses at the bottom and low ...

May 21, 2022
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Assembly code vs Machine code vs Object code?

What is the difference between object code, machine code and assembly code? Can you give a visual example of their difference? 10 Answers ...

May 21, 2022
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What is a retpoline and how does it work?

In order to mitigate against kernel or cross-process memory disclosure (the Spectre attack), the Linux kernel1 will be compiled with a new option, ...

May 20, 2022
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