From 9645be0af1b1d5cb0ad5892d5464e1b23c51b550 Mon Sep 17 00:00:00 2001 From: chai <chaifix@163.com> Date: Sat, 11 May 2019 22:54:56 +0800 Subject: *init --- source/3rd-party/SDL2/src/cpuinfo/SDL_simd.h | 88 ++++++++++++++++++++++++++++ 1 file changed, 88 insertions(+) create mode 100644 source/3rd-party/SDL2/src/cpuinfo/SDL_simd.h (limited to 'source/3rd-party/SDL2/src/cpuinfo/SDL_simd.h') diff --git a/source/3rd-party/SDL2/src/cpuinfo/SDL_simd.h b/source/3rd-party/SDL2/src/cpuinfo/SDL_simd.h new file mode 100644 index 0000000..e2b28bc --- /dev/null +++ b/source/3rd-party/SDL2/src/cpuinfo/SDL_simd.h @@ -0,0 +1,88 @@ +/* + Simple DirectMedia Layer + Copyright (C) 1997-2018 Sam Lantinga <slouken@libsdl.org> + + This software is provided 'as-is', without any express or implied + warranty. In no event will the authors be held liable for any damages + arising from the use of this software. + + Permission is granted to anyone to use this software for any purpose, + including commercial applications, and to alter it and redistribute it + freely, subject to the following restrictions: + + 1. The origin of this software must not be misrepresented; you must not + claim that you wrote the original software. If you use this software + in a product, an acknowledgment in the product documentation would be + appreciated but is not required. + 2. Altered source versions must be plainly marked as such, and must not be + misrepresented as being the original software. + 3. This notice may not be removed or altered from any source distribution. +*/ + +#include "SDL.h" +#include "../SDL_internal.h" + +/** + * \brief Report the alignment this system needs for SIMD allocations. + * + * This will return the minimum number of bytes to which a pointer must be + * aligned to be compatible with SIMD instructions on the current machine. + * For example, if the machine supports SSE only, it will return 16, but if + * it supports AVX-512F, it'll return 64 (etc). This only reports values for + * instruction sets 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. + */ +extern size_t SDL_SIMDGetAlignment(void); + +/** + * \brief Allocate memory in a SIMD-friendly way. + * + * 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. + * + * 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. + * + * You must free this memory with SDL_FreeSIMD(), not free() or SDL_free() + * or delete[], etc. + * + * 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. + * + * SDL_AllocSIMD(0) will return a non-NULL pointer, assuming the system isn't + * out of memory. + * + * \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. + * + * \sa SDL_SIMDAlignment + * \sa SDL_SIMDFree + */ +extern void * SDL_SIMDAlloc(const size_t len); + +/** + * \brief Deallocate memory obtained from SDL_SIMDAlloc + * + * It is not valid to use this function on a pointer from anything but + * SDL_SIMDAlloc(). It can't be used on pointers from malloc, realloc, + * SDL_malloc, memalign, new[], etc. + * + * However, SDL_SIMDFree(NULL) is a legal no-op. + * + * \sa SDL_SIMDAlloc + */ +extern void SDL_SIMDFree(void *ptr); + +/* vi: set ts=4 sw=4 expandtab: */ + -- cgit v1.1-26-g67d0