[FFmpeg-devel] [PATCH 2/3] vcodec/pictordec: avoid pointers in picmemset()
Michael Niedermayer
michael at niedermayer.cc
Sat Apr 13 02:36:46 EEST 2019
Improves overall speed by about 3%
Testcase: 14124/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_PICTOR_fuzzer-5633887734071296
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
---
libavcodec/pictordec.c | 29 ++++++++++++++++++-----------
1 file changed, 18 insertions(+), 11 deletions(-)
diff --git a/libavcodec/pictordec.c b/libavcodec/pictordec.c
index 65d2d49060..af99c486b8 100644
--- a/libavcodec/pictordec.c
+++ b/libavcodec/pictordec.c
@@ -63,22 +63,25 @@ static void picmemset(PicContext *s, AVFrame *frame, unsigned value, int run,
uint8_t *d;
int shift = *plane * bits_per_plane;
unsigned mask = ((1U << bits_per_plane) - 1) << shift;
+ int xl = *x;
+ int yl = *y;
+ int planel = *plane;
value <<= shift;
while (run > 0) {
int j;
for (j = 8-bits_per_plane; j >= 0; j -= bits_per_plane) {
- d = frame->data[0] + *y * frame->linesize[0];
- d[*x] |= (value >> j) & mask;
- *x += 1;
- if (*x == s->width) {
- *y -= 1;
- *x = 0;
- if (*y < 0) {
- *y = s->height - 1;
- *plane += 1;
- if (*plane >= s->nb_planes)
- return;
+ d = frame->data[0] + yl * frame->linesize[0];
+ d[xl] |= (value >> j) & mask;
+ xl += 1;
+ if (xl == s->width) {
+ yl -= 1;
+ xl = 0;
+ if (yl < 0) {
+ yl = s->height - 1;
+ planel += 1;
+ if (planel >= s->nb_planes)
+ goto end;
value <<= bits_per_plane;
mask <<= bits_per_plane;
}
@@ -86,6 +89,10 @@ static void picmemset(PicContext *s, AVFrame *frame, unsigned value, int run,
}
run--;
}
+end:
+ *x = xl;
+ *y = yl;
+ *plane = planel;
}
static const uint8_t cga_mode45_index[6][4] = {
--
2.21.0
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