From 05d3fd44d7ab34b2b456c2fad9e84651575a8ae4 Mon Sep 17 00:00:00 2001
From: Michael Niedermayer <michaelni@gmx.at>
Date: Tue, 23 Dec 2008 22:04:34 +0000
Subject: [PATCH] Integrate get_te0_golomb() calls into the code, this allows
 some checks to be avoided and the function is pretty small. 3% speedup,
 though this is probably due to changed inlining and not directly this change.

Originally committed as revision 16301 to svn://svn.ffmpeg.org/ffmpeg/trunk
---
 libavcodec/h264.c | 33 +++++++++++++++++++++++++++++----
 1 file changed, 29 insertions(+), 4 deletions(-)

diff --git a/libavcodec/h264.c b/libavcodec/h264.c
index 12bf126..0544bd8 100644
--- a/libavcodec/h264.c
+++ b/libavcodec/h264.c
@@ -4500,11 +4500,18 @@ decode_intra_mb:
             for(i=0; i<4; i++){
                 if(IS_DIRECT(h->sub_mb_type[i])) continue;
                 if(IS_DIR(h->sub_mb_type[i], 0, list)){
-                    unsigned int tmp = get_te0_golomb(&s->gb, ref_count); //FIXME init to 0 before and skip?
+                    unsigned int tmp;
+                    if(ref_count == 1){
+                        tmp= 0;
+                    }else if(ref_count == 2){
+                        tmp= get_bits1(&s->gb)^1;
+                    }else{
+                        tmp= get_ue_golomb_31(&s->gb);
                     if(tmp>=ref_count){
                         av_log(h->s.avctx, AV_LOG_ERROR, "ref %u overflow\n", tmp);
                         return -1;
                     }
+                    }
                     ref[list][i]= tmp;
                 }else{
                  //FIXME
@@ -4569,11 +4576,17 @@ decode_intra_mb:
             for(list=0; list<h->list_count; list++){
                     unsigned int val;
                     if(IS_DIR(mb_type, 0, list)){
-                        val= get_te0_golomb(&s->gb, h->ref_count[list]);
+                        if(h->ref_count[list]==1){
+                            val= 0;
+                        }else if(h->ref_count[list]==2){
+                            val= get_bits1(&s->gb)^1;
+                        }else{
+                        val= get_ue_golomb_31(&s->gb);
                         if(val >= h->ref_count[list]){
                             av_log(h->s.avctx, AV_LOG_ERROR, "ref %u overflow\n", val);
                             return -1;
                         }
+                        }
                     }else
                         val= LIST_NOT_USED&0xFF;
                     fill_rectangle(&h->ref_cache[list][ scan8[0] ], 4, 4, 8, val, 1);
@@ -4597,11 +4610,17 @@ decode_intra_mb:
                     for(i=0; i<2; i++){
                         unsigned int val;
                         if(IS_DIR(mb_type, i, list)){
-                            val= get_te0_golomb(&s->gb, h->ref_count[list]);
+                            if(h->ref_count[list] == 1){
+                                val= 0;
+                            }else if(h->ref_count[list] == 2){
+                                val= get_bits1(&s->gb)^1;
+                            }else{
+                            val= get_ue_golomb_31(&s->gb);
                             if(val >= h->ref_count[list]){
                                 av_log(h->s.avctx, AV_LOG_ERROR, "ref %u overflow\n", val);
                                 return -1;
                             }
+                            }
                         }else
                             val= LIST_NOT_USED&0xFF;
                         fill_rectangle(&h->ref_cache[list][ scan8[0] + 16*i ], 4, 2, 8, val, 1);
@@ -4628,11 +4647,17 @@ decode_intra_mb:
                     for(i=0; i<2; i++){
                         unsigned int val;
                         if(IS_DIR(mb_type, i, list)){ //FIXME optimize
-                            val= get_te0_golomb(&s->gb, h->ref_count[list]);
+                            if(h->ref_count[list]==1){
+                                val= 0;
+                            }else if(h->ref_count[list]==2){
+                                val= get_bits1(&s->gb)^1;
+                            }else{
+                            val= get_ue_golomb_31(&s->gb);
                             if(val >= h->ref_count[list]){
                                 av_log(h->s.avctx, AV_LOG_ERROR, "ref %u overflow\n", val);
                                 return -1;
                             }
+                            }
                         }else
                             val= LIST_NOT_USED&0xFF;
                         fill_rectangle(&h->ref_cache[list][ scan8[0] + 2*i ], 2, 4, 8, val, 1);
-- 
2.7.4