SDL_GetSIMDAlignment(3)

📦
version 3.4.18 · 9 versions
, in fedora 43, fedora 44

💅 SDL_GetSIMDAlignment 💅

okay bestie, welcome to the SDL3 FUNCTIONS corner of the manual — this one's about SDL_GetSIMDAlignment, aka the glow-up your pointers need before SIMD will even look at them. ✨

🌸 NAME 🌸

SDL_GetSIMDAlignment — report the alignment this system needs for SIMD allocations.

🦋 SYNOPSIS 🦋

#include <SDL3/SDL_cpuinfo.h>

size_t SDL_GetSIMDAlignment(void);

✨ DESCRIPTION ✨

so basically, this function tells you the minimum number of bytes that a pointer has to be aligned to if you want it to be compatible with the SIMD instructions on the machine you're running on. it's giving alignment requirement reveal, and honestly? iconic.

for example, if the machine supports SSE only, it will return 16. but if it supports AVX-512F, it'll return 64 (etc). no cap, the number just goes up with the spice level of your instruction sets. 🔥

now here's the lowkey important part, bestie — it only reports values for instruction sets that SDL knows about. so if your SDL build doesn't have SDL_HasAVX512F(), then it might return 16 for the SSE support it sees, and not 64 for the AVX-512 instructions that exist but SDL doesn't know about. plan accordingly. 💀

this is the "it's not lying, it just doesn't know" situation. don't @ me, @ your build config.

🎀 RETURN VALUE 🎀

returns the alignment in bytes needed for available, known SIMD instructions. that's the number, that's the whole vibe. 🫶

🧚 THREAD SAFETY 🧚

it is safe to call this function from any thread. so go off, call it from wherever, it's not gonna be messy about it. ✨

🌈 AVAILABILITY 🌈

this function is available since SDL 3.2.0.

👑 SEE ALSO 👑

okay that's the whole page, mwah 💋 — brought to you by the lovely folks at Simple Directmedia Layer, SDL 3.4.18. go align your pointers, bestie, you got this. 💖

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