Files
ppsspp/ext/ffmpeg/libavutil/intmath.h
T
Henrik RydgårdandClaude Opus 5.5 d0e3141f43 FFmpeg: Vendor what PPSSPP uses into ext/ffmpeg, drop the submodule
The ffmpeg submodule held prebuilt libraries for every platform next to the
sources (about 1.5 GB checked out), and nothing uses those any more. Only the
needed sources are copied in, from the submodule's commit, along with every
header and template they include. The path is new, so checking out commits on
either side of this works.

It's also cut down to what PPSSPP uses: the H.264, AAC, MP3, ATRAC3 and ATRAC3+
decoders, the H.264 parser, the demuxers as before, and the FFV1 encoder, AVI
muxer and file protocol for AVI dumping. config.h takes its CONFIG_ values from
FFmpeg 3.0.2's own configure run with just those enabled. The raw H.264 demuxer
stays even though nothing opens raw H.264: probing PSMF data uses it to identify
the video stream's codec, which otherwise comes out as none.

On top of that:
- The files nothing links (configure would build them, but they're never pulled
  out of the static library, going by the GCC link map) are left out: mostly
  libavutil's crypto and hashing and the alternative DCT/IDCT/FFT versions.
- libswresample isn't built, now that nothing uses it.
- The H.264 decoder only does 8-bit video, which is all the PSP has. The SPS
  parser rejects any other bit depth, and the DSP files no longer build their 9-
  to 16-bit variants, which the linker kept because the init functions pick one
  by bit depth at run time.

That's 160 files to compile instead of 277, and 391 of FFmpeg's vendored, about
5.8 MB. The README in ext/ffmpeg has what was done, the PPSSPP patches in the
copy, how to add a component, and the tradeoffs.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
2026-10-25 22:27:54 +01:00

166 lines
3.7 KiB
C

/*
* Copyright (c) 2010 Mans Rullgard <mans@mansr.com>
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef AVUTIL_INTMATH_H
#define AVUTIL_INTMATH_H
#include <stdint.h>
#include "config.h"
#include "attributes.h"
#if ARCH_ARM
# include "arm/intmath.h"
#endif
#if ARCH_X86
# include "x86/intmath.h"
#endif
#if HAVE_FAST_CLZ
#if AV_GCC_VERSION_AT_LEAST(3,4)
#ifndef ff_log2
# define ff_log2(x) (31 - __builtin_clz((x)|1))
# ifndef ff_log2_16bit
# define ff_log2_16bit av_log2
# endif
#endif /* ff_log2 */
#endif /* AV_GCC_VERSION_AT_LEAST(3,4) */
#endif
extern const uint8_t ff_log2_tab[256];
#ifndef ff_log2
#define ff_log2 ff_log2_c
static av_always_inline av_const int ff_log2_c(unsigned int v)
{
int n = 0;
if (v & 0xffff0000) {
v >>= 16;
n += 16;
}
if (v & 0xff00) {
v >>= 8;
n += 8;
}
n += ff_log2_tab[v];
return n;
}
#endif
#ifndef ff_log2_16bit
#define ff_log2_16bit ff_log2_16bit_c
static av_always_inline av_const int ff_log2_16bit_c(unsigned int v)
{
int n = 0;
if (v & 0xff00) {
v >>= 8;
n += 8;
}
n += ff_log2_tab[v];
return n;
}
#endif
#define av_log2 ff_log2
#define av_log2_16bit ff_log2_16bit
/**
* @addtogroup lavu_math
* @{
*/
#if HAVE_FAST_CLZ
#if AV_GCC_VERSION_AT_LEAST(3,4)
#ifndef ff_ctz
#define ff_ctz(v) __builtin_ctz(v)
#endif
#ifndef ff_ctzll
#define ff_ctzll(v) __builtin_ctzll(v)
#endif
#ifndef ff_clz
#define ff_clz(v) __builtin_clz(v)
#endif
#endif
#endif
#ifndef ff_ctz
#define ff_ctz ff_ctz_c
/**
* Trailing zero bit count.
*
* @param v input value. If v is 0, the result is undefined.
* @return the number of trailing 0-bits
*/
/* We use the De-Bruijn method outlined in:
* http://supertech.csail.mit.edu/papers/debruijn.pdf. */
static av_always_inline av_const int ff_ctz_c(int v)
{
static const uint8_t debruijn_ctz32[32] = {
0, 1, 28, 2, 29, 14, 24, 3, 30, 22, 20, 15, 25, 17, 4, 8,
31, 27, 13, 23, 21, 19, 16, 7, 26, 12, 18, 6, 11, 5, 10, 9
};
return debruijn_ctz32[(uint32_t)((v & -v) * 0x077CB531U) >> 27];
}
#endif
#ifndef ff_ctzll
#define ff_ctzll ff_ctzll_c
/* We use the De-Bruijn method outlined in:
* http://supertech.csail.mit.edu/papers/debruijn.pdf. */
static av_always_inline av_const int ff_ctzll_c(long long v)
{
static const uint8_t debruijn_ctz64[64] = {
0, 1, 2, 53, 3, 7, 54, 27, 4, 38, 41, 8, 34, 55, 48, 28,
62, 5, 39, 46, 44, 42, 22, 9, 24, 35, 59, 56, 49, 18, 29, 11,
63, 52, 6, 26, 37, 40, 33, 47, 61, 45, 43, 21, 23, 58, 17, 10,
51, 25, 36, 32, 60, 20, 57, 16, 50, 31, 19, 15, 30, 14, 13, 12
};
return debruijn_ctz64[(uint64_t)((v & -v) * 0x022FDD63CC95386DU) >> 58];
}
#endif
#ifndef ff_clz
#define ff_clz ff_clz_c
static av_always_inline av_const unsigned ff_clz_c(unsigned x)
{
unsigned i = sizeof(x) * 8;
while (x) {
x >>= 1;
i--;
}
return i;
}
#endif
#if AV_GCC_VERSION_AT_LEAST(3,4)
#ifndef av_parity
#define av_parity __builtin_parity
#endif
#endif
/**
* @}
*/
#endif /* AVUTIL_INTMATH_H */