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<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><meta name="generator" content="rustdoc"><meta name="description" content="API documentation for the Rust `SDL_SIMDAlloc` fn in crate `sdl2_sys`."><meta name="keywords" content="rust, rustlang, rust-lang, SDL_SIMDAlloc"><title>sdl2_sys::SDL_SIMDAlloc - Rust</title><link rel="stylesheet" type="text/css" href="../normalize.css"><link rel="stylesheet" type="text/css" href="../rustdoc.css" id="mainThemeStyle"><link rel="stylesheet" type="text/css" href="../dark.css"><link rel="stylesheet" type="text/css" href="../light.css" id="themeStyle"><script src="../storage.js"></script><noscript><link rel="stylesheet" href="../noscript.css"></noscript><link rel="shortcut icon" href="../favicon.ico"><style type="text/css">#crate-search{background-image:url("../down-arrow.svg");}</style></head><body class="rustdoc fn"><!--[if lte IE 8]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="sidebar"><div class="sidebar-menu">&#9776;</div><a href='../sdl2_sys/index.html'><div class='logo-container'><img src='../rust-logo.png' alt='logo'></div></a><div class="sidebar-elems"><p class='location'><a href='index.html'>sdl2_sys</a></p><script>window.sidebarCurrent = {name: 'SDL_SIMDAlloc', ty: 'fn', relpath: ''};</script><script defer src="sidebar-items.js"></script></div></nav><div class="theme-picker"><button id="theme-picker" aria-label="Pick another theme!"><img src="../brush.svg" width="18" alt="Pick another theme!"></button><div id="theme-choices"></div></div><script src="../theme.js"></script><nav class="sub"><form class="search-form"><div class="search-container"><div><select id="crate-search"><option value="All crates">All crates</option></select><input class="search-input" name="search" disabled autocomplete="off" spellcheck="false" placeholder="Click or press S to search, ? for more options…" type="search"></div><a id="settings-menu" href="../settings.html"><img src="../wheel.svg" width="18" alt="Change settings"></a></div></form></nav><section id="main" class="content"><h1 class='fqn'><span class='out-of-band'><span id='render-detail'><a id="toggle-all-docs" href="javascript:void(0)" title="collapse all docs">[<span class='inner'>&#x2212;</span>]</a></span><a class='srclink' href='../src/sdl2_sys/Users/travis/build/Rust-SDL2/rust-sdl2/target/debug/build/sdl2-sys-f32779682524d647/out/sdl_bindings.rs.html#5631' title='goto source code'>[src]</a></span><span class='in-band'>Function <a href='index.html'>sdl2_sys</a>::<wbr><a class="fn" href=''>SDL_SIMDAlloc</a></span></h1><pre class='rust fn'>pub unsafe extern &quot;C&quot; fn SDL_SIMDAlloc(len: <a class="type" href="../sdl2_sys/type.size_t.html" title="type sdl2_sys::size_t">size_t</a>) -&gt; *mut <a class="enum" href="https://doc.rust-lang.org/nightly/core/ffi/enum.c_void.html" title="enum core::ffi::c_void">c_void</a></pre><div class='docblock'><p>\brief Allocate memory in a SIMD-friendly way.</p>
<p>This will allocate a block of memory that is suitable for use with SIMD
instructions. Specifically, it will be properly aligned and padded for
the system's supported vector instructions.</p>
<p>The memory returned will be padded such that it is safe to read or write
an incomplete vector at the end of the memory block. This can be useful
so you don't have to drop back to a scalar fallback at the end of your
SIMD processing loop to deal with the final elements without overflowing
the allocated buffer.</p>
<p>You must free this memory with SDL_FreeSIMD(), not free() or SDL_free()
or delete[], etc.</p>
<p>Note that SDL will only deal with SIMD instruction sets it is aware of;
for example, SDL 2.0.8 knows that SSE wants 16-byte vectors
(SDL_HasSSE()), and AVX2 wants 32 bytes (SDL_HasAVX2()), but doesn't
know that AVX-512 wants 64. To be clear: if you can't decide to use an
instruction set with an SDL_Has*() function, don't use that instruction
set with memory allocated through here.</p>
<p>SDL_AllocSIMD(0) will return a non-NULL pointer, assuming the system isn't
out of memory.</p>
<p>\param len The length, in bytes, of the block to allocated. The actual
allocated block might be larger due to padding, etc.
\return Pointer to newly-allocated block, NULL if out of memory.</p>
<p>\sa SDL_SIMDAlignment
\sa SDL_SIMDFree</p>
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