Ask HN: What are some examples of beautiful x86 assembly code? • Hacker News Board

Re: Ask HN: What are some examples of beautiful x86 assembly code?

#61

Post by zero_one_one » Fri, Apr 27, 2018, 6:18 PM UTC

abhishekjha wrote: post #28

booblik wrote: post #26

Earlier quoted context omitted.

No, loop decrements rcx until it reaches zero and then stops

But rcx has not been initialised.

The code above I believe is the point to jump to when the register has been assigned some value for x. Think along the same lines as a function call once the pre-amble is out of the way (or a ‘goto’ by someone who knows when to use it!)

Re: Ask HN: What are some examples of beautiful x86 assembly code?

#62

Post by 0x7f800000 » Fri, Apr 27, 2018, 6:40 PM UTC

Michael Abrash's assembly optimizations for the Quake engine.

Re: Ask HN: What are some examples of beautiful x86 assembly code?

#63

Post by trentnelson » Fri, Apr 27, 2018, 6:49 PM UTC

This injection thunk I wrote in order to do facilitate remote code and context (file handles, event handles, shared memory maps etc) injection: https://github.com/tpn/tracer/blob/master/Asm/InjectionThunk...

Re: Ask HN: What are some examples of beautiful x86 assembly code?

#64

Post by thecompilr » Fri, Apr 27, 2018, 6:56 PM UTC

_o_ wrote: post #47

The coolest one liner is xor eax,eax :) 1 cycle for setting register to 0.

Yeah, but with the side effect of clearing the flag registers. So can't be used between operations that rely on flags. Alternatively it is great to break false flag dependency.

Re: Ask HN: What are some examples of beautiful x86 assembly code?

#65

Post by gesman » Fri, Apr 27, 2018, 6:57 PM UTC

I remember I wrote a 6 bytes code to destroy information on the whole hard drive.

Kind of opposite of what you're asking for :)

Re: Ask HN: What are some examples of beautiful x86 assembly code?

#66

Post by davibu » Fri, Apr 27, 2018, 6:57 PM UTC

Here's a mix between C++ and asm. https://www.codeproject.com/Articles/36907/How-to-develop-yo...

Re: Ask HN: What are some examples of beautiful x86 assembly code?

#67

Post by mtve » Fri, Apr 27, 2018, 7:08 PM UTC

not quite the assembly, but you may look at small intros at https://www.pouet.net/prodlist.php of sizes 32 bytes and so on.

many intros are provided with source codes, and others could easily be viewed in disassemblers.

especially look at intros by such brilliant people like Digimind and Řrřola.

Re: Ask HN: What are some examples of beautiful x86 assembly code?

#68

Post by danmg » Fri, Apr 27, 2018, 7:11 PM UTC

cosarara wrote: post #39

indescions_2018 wrote: post #36

Pokémon! GBA (ARM7) is even being used in some undergrad level OS classes. Although you may get more mileage out of RP3 development. disassembly of Pokémon Red/Blue https://github.com/pret/pokered TONC GBA Programming Principles https://www.coranac.com/tonc/text/toc.htm

Red and blue are gbc (z80-like, not ARM).

GB was Sharp LR35902. Similar but not quite an z80 or x80.

https://realboyemulator.wordpress.com/2013/01/02/the-nintend...

Re: Ask HN: What are some examples of beautiful x86 assembly code?

#69

Post by neengineering » Fri, Apr 27, 2018, 7:15 PM UTC

There were some pretty good Win32 API tutorials back in the day. It was similar to this, if not it:

http://win32assembly.programminghorizon.com/

It was quite enlightening to see common program constructs done only in assembly.

Re: Ask HN: What are some examples of beautiful x86 assembly code?

#70

Post by tiffanyh » Fri, Apr 27, 2018, 7:19 PM UTC

Isn't LuaJIT assembler DYNASM often referred to as poetry

https://luajit.org/dynasm.html