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mirror of https://github.com/mpv-player/mpv synced 2024-11-14 22:48:35 +01:00
mpv/video/gpu_memcpy.c
wm4 0ae8aebb89 video: refactor GPU memcpy usage
Make the GPU memcpy from the dxva2 code generally useful to other parts
of the player.

We need to check at configure time whether SSE intrinsics work at all.
(At least in this form, they won't work on clang, for example. It also
won't work on non-x86.)

Introduce a mp_image_copy_gpu(), and make the dxva2 code use it. Do some
awkward stuff to share the existing code used by mp_image_copy(). I'm
hoping that FFmpeg will sooner or later provide a function like this, so
we can remove most of this again. (There is a patch, bit it's stuck in
limbo since forever.)

All this is used by the following commit.
2015-09-25 19:18:16 +02:00

136 lines
4.5 KiB
C

/*
* Copyright (C) 2011-2014 Hendrik Leppkes
* http://www.1f0.de
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Taken from the QuickSync decoder by Eric Gur
*/
#pragma GCC push_options
#pragma GCC target("sse4.1")
#include <smmintrin.h>
#include <stdbool.h>
#include <string.h>
#include "gpu_memcpy.h"
// gpu_memcpy is a memcpy style function that copied data very fast from a
// GPU tiled memory (write back)
// Performance tip: page offset (12 lsb) of both addresses should be different
// optimally use a 2K offset between them.
void *gpu_memcpy(void *restrict d, const void *restrict s, size_t size)
{
static const size_t regsInLoop = sizeof(size_t) * 2; // 8 or 16
if (d == NULL || s == NULL) return NULL;
// If memory is not aligned, use memcpy
bool isAligned = (((size_t)(s) | (size_t)(d)) & 0xF) == 0;
if (!isAligned)
{
return memcpy(d, s, size);
}
__m128i xmm0, xmm1, xmm2, xmm3, xmm4, xmm5, xmm6, xmm7;
#ifdef __x86_64__
__m128i xmm8, xmm9, xmm10, xmm11, xmm12, xmm13, xmm14, xmm15;
#endif
size_t reminder = size & (regsInLoop * sizeof(xmm0) - 1); // Copy 128 or 256 bytes every loop
size_t end = 0;
__m128i* pTrg = (__m128i*)d;
__m128i* pTrgEnd = pTrg + ((size - reminder) >> 4);
__m128i* pSrc = (__m128i*)s;
// Make sure source is synced - doesn't hurt if not needed.
_mm_sfence();
while (pTrg < pTrgEnd)
{
// _mm_stream_load_si128 emits the Streaming SIMD Extensions 4 (SSE4.1) instruction MOVNTDQA
// Fastest method for copying GPU RAM. Available since Penryn (45nm Core 2 Duo/Quad)
xmm0 = _mm_stream_load_si128(pSrc);
xmm1 = _mm_stream_load_si128(pSrc + 1);
xmm2 = _mm_stream_load_si128(pSrc + 2);
xmm3 = _mm_stream_load_si128(pSrc + 3);
xmm4 = _mm_stream_load_si128(pSrc + 4);
xmm5 = _mm_stream_load_si128(pSrc + 5);
xmm6 = _mm_stream_load_si128(pSrc + 6);
xmm7 = _mm_stream_load_si128(pSrc + 7);
#ifdef __x86_64__ // Use all 16 xmm registers
xmm8 = _mm_stream_load_si128(pSrc + 8);
xmm9 = _mm_stream_load_si128(pSrc + 9);
xmm10 = _mm_stream_load_si128(pSrc + 10);
xmm11 = _mm_stream_load_si128(pSrc + 11);
xmm12 = _mm_stream_load_si128(pSrc + 12);
xmm13 = _mm_stream_load_si128(pSrc + 13);
xmm14 = _mm_stream_load_si128(pSrc + 14);
xmm15 = _mm_stream_load_si128(pSrc + 15);
#endif
pSrc += regsInLoop;
// _mm_store_si128 emit the SSE2 intruction MOVDQA (aligned store)
_mm_store_si128(pTrg , xmm0);
_mm_store_si128(pTrg + 1, xmm1);
_mm_store_si128(pTrg + 2, xmm2);
_mm_store_si128(pTrg + 3, xmm3);
_mm_store_si128(pTrg + 4, xmm4);
_mm_store_si128(pTrg + 5, xmm5);
_mm_store_si128(pTrg + 6, xmm6);
_mm_store_si128(pTrg + 7, xmm7);
#ifdef __x86_64__ // Use all 16 xmm registers
_mm_store_si128(pTrg + 8, xmm8);
_mm_store_si128(pTrg + 9, xmm9);
_mm_store_si128(pTrg + 10, xmm10);
_mm_store_si128(pTrg + 11, xmm11);
_mm_store_si128(pTrg + 12, xmm12);
_mm_store_si128(pTrg + 13, xmm13);
_mm_store_si128(pTrg + 14, xmm14);
_mm_store_si128(pTrg + 15, xmm15);
#endif
pTrg += regsInLoop;
}
// Copy in 16 byte steps
if (reminder >= 16)
{
size = reminder;
reminder = size & 15;
end = size >> 4;
for (size_t i = 0; i < end; ++i)
{
pTrg[i] = _mm_stream_load_si128(pSrc + i);
}
}
// Copy last bytes - shouldn't happen as strides are modulu 16
if (reminder)
{
__m128i temp = _mm_stream_load_si128(pSrc + end);
char* ps = (char*)(&temp);
char* pt = (char*)(pTrg + end);
for (size_t i = 0; i < reminder; ++i)
{
pt[i] = ps[i];
}
}
return d;
}