[FFmpeg-cvslog] avcodec/ivi: Reduce dereferencing structs in inner loop of ivi_process_empty_tile()
Michael Niedermayer
git at videolan.org
Mon Apr 1 00:26:40 EEST 2019
ffmpeg | branch: master | Michael Niedermayer <michael at niedermayer.cc> | Sun Mar 24 23:20:19 2019 +0100| [4eec0082599adf4b7a25ce6e6ec761f6849783a3] | committer: Michael Niedermayer
avcodec/ivi: Reduce dereferencing structs in inner loop of ivi_process_empty_tile()
This speeds the code up by about 15%
Testcase: 13779/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_INDEO4_fuzzer-5699589711069184
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=4eec0082599adf4b7a25ce6e6ec761f6849783a3
---
libavcodec/ivi.c | 45 +++++++++++++++++++++++++--------------------
1 file changed, 25 insertions(+), 20 deletions(-)
diff --git a/libavcodec/ivi.c b/libavcodec/ivi.c
index f87964afd4..0f77873a83 100644
--- a/libavcodec/ivi.c
+++ b/libavcodec/ivi.c
@@ -775,24 +775,29 @@ static int ivi_process_empty_tile(AVCodecContext *avctx, const IVIBandDesc *band
const int16_t *src;
int16_t *dst;
ivi_mc_func mc_no_delta_func;
+ int clear_first = !band->qdelta_present && !band->plane && !band->band_num;
+ int mb_size = band->mb_size;
+ int xend = tile->xpos + tile->width;
+ int is_halfpel = band->is_halfpel;
+ int pitch = band->pitch;
- if (tile->num_MBs != IVI_MBs_PER_TILE(tile->width, tile->height, band->mb_size)) {
+ if (tile->num_MBs != IVI_MBs_PER_TILE(tile->width, tile->height, mb_size)) {
av_log(avctx, AV_LOG_ERROR, "Allocated tile size %d mismatches "
"parameters %d in ivi_process_empty_tile()\n",
- tile->num_MBs, IVI_MBs_PER_TILE(tile->width, tile->height, band->mb_size));
+ tile->num_MBs, IVI_MBs_PER_TILE(tile->width, tile->height, mb_size));
return AVERROR_INVALIDDATA;
}
- offs = tile->ypos * band->pitch + tile->xpos;
+ offs = tile->ypos * pitch + tile->xpos;
mb = tile->mbs;
ref_mb = tile->ref_mbs;
- row_offset = band->mb_size * band->pitch;
+ row_offset = mb_size * pitch;
need_mc = 0; /* reset the mc tracking flag */
- for (y = tile->ypos; y < (tile->ypos + tile->height); y += band->mb_size) {
+ for (y = tile->ypos; y < (tile->ypos + tile->height); y += mb_size) {
mb_offset = offs;
- for (x = tile->xpos; x < (tile->xpos + tile->width); x += band->mb_size) {
+ for (x = tile->xpos; x < xend; x += mb_size) {
mb->xpos = x;
mb->ypos = y;
mb->buf_offs = mb_offset;
@@ -800,7 +805,7 @@ static int ivi_process_empty_tile(AVCodecContext *avctx, const IVIBandDesc *band
mb->type = 1; /* set the macroblocks type = INTER */
mb->cbp = 0; /* all blocks are empty */
- if (!band->qdelta_present && !band->plane && !band->band_num) {
+ if (clear_first) {
mb->q_delta = band->glob_quant;
mb->mv_x = 0;
mb->mv_y = 0;
@@ -823,15 +828,15 @@ static int ivi_process_empty_tile(AVCodecContext *avctx, const IVIBandDesc *band
{
int dmv_x, dmv_y, cx, cy;
- dmv_x = mb->mv_x >> band->is_halfpel;
- dmv_y = mb->mv_y >> band->is_halfpel;
- cx = mb->mv_x & band->is_halfpel;
- cy = mb->mv_y & band->is_halfpel;
+ dmv_x = mb->mv_x >> is_halfpel;
+ dmv_y = mb->mv_y >> is_halfpel;
+ cx = mb->mv_x & is_halfpel;
+ cy = mb->mv_y & is_halfpel;
if ( mb->xpos + dmv_x < 0
- || mb->xpos + dmv_x + band->mb_size + cx > band->pitch
+ || mb->xpos + dmv_x + mb_size + cx > pitch
|| mb->ypos + dmv_y < 0
- || mb->ypos + dmv_y + band->mb_size + cy > band->aheight) {
+ || mb->ypos + dmv_y + mb_size + cy > band->aheight) {
av_log(avctx, AV_LOG_ERROR, "MV out of bounds\n");
return AVERROR_INVALIDDATA;
}
@@ -841,13 +846,13 @@ static int ivi_process_empty_tile(AVCodecContext *avctx, const IVIBandDesc *band
}
mb++;
- mb_offset += band->mb_size;
+ mb_offset += mb_size;
} // for x
offs += row_offset;
} // for y
if (band->inherit_mv && need_mc) { /* apply motion compensation if there is at least one non-zero motion vector */
- num_blocks = (band->mb_size != band->blk_size) ? 4 : 1; /* number of blocks per mb */
+ num_blocks = (mb_size != band->blk_size) ? 4 : 1; /* number of blocks per mb */
mc_no_delta_func = (band->blk_size == 8) ? ff_ivi_mc_8x8_no_delta
: ff_ivi_mc_4x4_no_delta;
@@ -864,7 +869,7 @@ static int ivi_process_empty_tile(AVCodecContext *avctx, const IVIBandDesc *band
for (blk = 0; blk < num_blocks; blk++) {
/* adjust block position in the buffer according with its number */
- offs = mb->buf_offs + band->blk_size * ((blk & 1) + !!(blk & 2) * band->pitch);
+ offs = mb->buf_offs + band->blk_size * ((blk & 1) + !!(blk & 2) * pitch);
ret = ivi_mc(band, mc_no_delta_func, 0, offs,
mv_x, mv_y, 0, 0, mc_type, -1);
if (ret < 0)
@@ -873,12 +878,12 @@ static int ivi_process_empty_tile(AVCodecContext *avctx, const IVIBandDesc *band
}
} else {
/* copy data from the reference tile into the current one */
- src = band->ref_buf + tile->ypos * band->pitch + tile->xpos;
- dst = band->buf + tile->ypos * band->pitch + tile->xpos;
+ src = band->ref_buf + tile->ypos * pitch + tile->xpos;
+ dst = band->buf + tile->ypos * pitch + tile->xpos;
for (y = 0; y < tile->height; y++) {
memcpy(dst, src, tile->width*sizeof(band->buf[0]));
- src += band->pitch;
- dst += band->pitch;
+ src += pitch;
+ dst += pitch;
}
}
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