ATOMIC_DEC(3clc)

✨ NAME ✨

okay so bestie, meet atomic_dec — it's the atomic_dec functions, that's the whole name, short and sweet, no notes 💅

This page lives in the OpenCL Manual, and here's every single shape this function comes in (all four of them, don't skip any, I know you want to):

int atomic_dec(volatile global(3clc) int *p);

unsigned int atomic_dec(volatile global(3clc) unsigned int *p);

int atomic_dec(volatile local(3clc) int *p);

unsigned int atomic_dec(volatile local(3clc) unsigned int *p);

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🦋 DESCRIPTION 🦋

So here's the tea, and it's honestly so simple it's iconic:

• Read the 32-bit value stored at the location pointed by p — this lil guy is referred to as old, remember that name.
• Compute (old - 1).
• Store that result at the location pointed by p.
• The function returns old. Yes, the old one. Not the new one. It's giving post-decrement energy, fr fr.

And for the girlies who need the big numbers: a 64-bit version of this function, atom_dec(3clc), is enabled by cl_khr_int64_base_atomics(3clc). 👑

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🌈 SPECIFICATION 🌈

OpenCL Specification[1]

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💜 SEE ALSO 💜

• atomicFunctions(3clc)
• atom_dec(3clc)

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🎀 AUTHORS 🎀

The Khronos Group

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⭐ COPYRIGHT ⭐

Copyright © 2007-2011 The Khronos Group Inc.

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and/or associated documentation files (the "Materials"), to deal in the Materials without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Materials, and to permit persons to whom the Materials are furnished to do so, subject to the following conditions:

The condition is literally this, no cap:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Materials.

(that's the whole permission situation, and yes I kept every word, because legal text is not the place to freestyle 🫶)

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🌸 NOTES 🌸

1. OpenCL Specification, page 279, section 6.12.11 - Atomic Functions for 32-bit integers

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and that's the whole page bestie, you ate it 💖

signing off — brought to you by The Khronos Group, dated 01/14/2021, and the page itself is ATOMIC_DEC(3clc). mwah, go decrement something atomically 🧚✨