[FFmpeg-devel] [PATCH] Prores: Move large on-stack arrays into context instead.

[Reimar Döffinger]

The quantization matrices used in related code are also there,
so cache effects should not be (too) negative - not benchmarked though.

Signed-off-by: Reimar Döffinger <Reimar.Doeffinger at gmx.de>
---
 libavcodec/proresdec.c |   21 +++++++++++----------
 1 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/libavcodec/proresdec.c b/libavcodec/proresdec.c
index c56b258..0320f8a 100644
--- a/libavcodec/proresdec.c
+++ b/libavcodec/proresdec.c
@@ -42,6 +42,7 @@ typedef struct {
     AVFrame frame;
     DSPContext dsp;
     int frame_type;              ///< 0 = progressive, 1 = tff, 2 = bff
+    DECLARE_ALIGNED(16, DCTELEM, blocks)[8*4*64];
     uint8_t qmat_luma[64];
     uint8_t qmat_chroma[64];
     SliceContext *slices;
@@ -397,19 +398,19 @@ static void decode_slice_luma(AVCodecContext *avctx, SliceContext *slice,
                               const int *qmat)
 {
     ProresContext *ctx = avctx->priv_data;
-    DECLARE_ALIGNED(16, DCTELEM, blocks)[8*4*64], *block;
+    DCTELEM *block;
     GetBitContext gb;
     int i, blocks_per_slice = slice->mb_count<<2;
 
     for (i = 0; i < blocks_per_slice; i++)
-        ctx->dsp.clear_block(blocks+(i<<6));
+        ctx->dsp.clear_block(ctx->blocks+(i<<6));
 
     init_get_bits(&gb, buf, buf_size << 3);
 
-    decode_dc_coeffs(&gb, blocks, blocks_per_slice, qmat);
-    decode_ac_coeffs(avctx, &gb, blocks, blocks_per_slice, qmat);
+    decode_dc_coeffs(&gb, ctx->blocks, blocks_per_slice, qmat);
+    decode_ac_coeffs(avctx, &gb, ctx->blocks, blocks_per_slice, qmat);
 
-    block = blocks;
+    block = ctx->blocks;
     for (i = 0; i < slice->mb_count; i++) {
         ctx->idct_put(block+(0<<6), dst, dst_stride);
         ctx->idct_put(block+(1<<6), dst+16, dst_stride);
@@ -426,19 +427,19 @@ static void decode_slice_chroma(AVCodecContext *avctx, SliceContext *slice,
                                 const int *qmat)
 {
     ProresContext *ctx = avctx->priv_data;
-    DECLARE_ALIGNED(16, DCTELEM, blocks)[8*4*64], *block;
+    DCTELEM *block;
     GetBitContext gb;
     int i, blocks_per_slice = slice->mb_count*2;
 
     for (i = 0; i < blocks_per_slice; i++)
-        ctx->dsp.clear_block(blocks+(i<<6));
+        ctx->dsp.clear_block(ctx->blocks+(i<<6));
 
     init_get_bits(&gb, buf, buf_size << 3);
 
-    decode_dc_coeffs(&gb, blocks, blocks_per_slice, qmat);
-    decode_ac_coeffs(avctx, &gb, blocks, blocks_per_slice, qmat);
+    decode_dc_coeffs(&gb, ctx->blocks, blocks_per_slice, qmat);
+    decode_ac_coeffs(avctx, &gb, ctx->blocks, blocks_per_slice, qmat);
 
-    block = blocks;
+    block = ctx->blocks;
     for (i = 0; i < slice->mb_count; i++) {
         ctx->idct_put(block+(0<<6), dst,              dst_stride);
         ctx->idct_put(block+(1<<6), dst+8*dst_stride, dst_stride);
-- 
1.7.6.3