From fd3c34ff304aebbeba1e730957bef08280fc9e10 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Sat, 9 Nov 2019 21:52:26 +0100 Subject: [PATCH] avcodec/alsdec: Avoid 1 layer of pointer dereferences in INTERLEAVE_OUTPUT() This optimizes the code slightly (116 -> 80sec) Testcase: 18668/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_ALS_fuzzer-5710836719157248 Signed-off-by: Michael Niedermayer --- libavcodec/alsdec.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/libavcodec/alsdec.c b/libavcodec/alsdec.c index 4bc0e2bd84..babe30bdc7 100644 --- a/libavcodec/alsdec.c +++ b/libavcodec/alsdec.c @@ -1819,16 +1819,17 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame_ptr, { \ int##bps##_t *dest = (int##bps##_t*)frame->data[0]; \ int channels = avctx->channels; \ - int32_t **raw_samples = ctx->raw_samples; \ + int32_t *raw_samples = ctx->raw_samples[0]; \ + int raw_step = channels > 1 ? ctx->raw_samples[1] - raw_samples : 1; \ shift = bps - ctx->avctx->bits_per_raw_sample; \ if (!ctx->cs_switch) { \ for (sample = 0; sample < ctx->cur_frame_length; sample++) \ for (c = 0; c < channels; c++) \ - *dest++ = raw_samples[c][sample] * (1U << shift); \ + *dest++ = raw_samples[c*raw_step + sample] * (1U << shift); \ } else { \ for (sample = 0; sample < ctx->cur_frame_length; sample++) \ for (c = 0; c < channels; c++) \ - *dest++ = raw_samples[sconf->chan_pos[c]][sample] * (1U << shift);\ + *dest++ = raw_samples[sconf->chan_pos[c]*raw_step + sample] * (1U << shift);\ } \ }