ffmpeg roll of source to mar 9 version...

patched-ffmpeg-mt/libavcodec/get_bits.h

 /*
  * copyright (c) 2004 Michael Niedermayer <michaelni@gmx.at>
  *
  * This file is part of FFmpeg.
  *
  * FFmpeg is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2.1 of the License, or (at your option) any later version.
  *
@@ skipping 31 matching lines @@
 #if !defined(LIBMPEG2_BITSTREAM_READER) && !defined(A32_BITSTREAM_READER) && !defined(ALT_BITSTREAM_READER)
 #   if ARCH_ARM && !HAVE_FAST_UNALIGNED
 #       define A32_BITSTREAM_READER
 #   else
 #       define ALT_BITSTREAM_READER
 //#define LIBMPEG2_BITSTREAM_READER
 //#define A32_BITSTREAM_READER
 #   endif
 #endif
 
-#if ARCH_X86
-// avoid +32 for shift optimization (gcc should do that ...)
-static inline  int32_t NEG_SSR32( int32_t a, int8_t s){
-    __asm__ ("sarl %1, %0\n\t"
-         : "+r" (a)
-         : "ic" ((uint8_t)(-s))
-    );
-    return a;
-}
-static inline uint32_t NEG_USR32(uint32_t a, int8_t s){
-    __asm__ ("shrl %1, %0\n\t"
-         : "+r" (a)
-         : "ic" ((uint8_t)(-s))
-    );
-    return a;
-}
-#else
-#    define NEG_SSR32(a,s) ((( int32_t)(a))>>(32-(s)))
-#    define NEG_USR32(a,s) (((uint32_t)(a))>>(32-(s)))
-#endif
-
 /* bit input */
 /* buffer, buffer_end and size_in_bits must be present and used by every reader */
 typedef struct GetBitContext {
     const uint8_t *buffer, *buffer_end;
     /* Ugly, but clients of this bit reader do not seem to check for enough
      * data before calling. So we'll return 0's on overrun rather than crashing
      * with random read faults.
      */
     int buffer_exhausted;
     int buffer_enforcing;
@@ skipping 113 matching lines @@
         {\
             SKIP_CACHE(name, gb, num)\
             SKIP_COUNTER(name, gb, num)\
         }\
 
 #   define LAST_SKIP_BITS(name, gb, num) SKIP_COUNTER(name, gb, num)
 #   define LAST_SKIP_CACHE(name, gb, num) ;
 
 # ifdef ALT_BITSTREAM_READER_LE
 #   define SHOW_UBITS(name, gb, num)\
-        ((name##_cache) & (NEG_USR32(0xffffffff,num)))
+        zero_extend(name##_cache, num)
 
 #   define SHOW_SBITS(name, gb, num)\
-        NEG_SSR32((name##_cache)<<(32-(num)), num)
+        sign_extend(name##_cache, num)
 # else
 #   define SHOW_UBITS(name, gb, num)\
         NEG_USR32(name##_cache, num)
 
 #   define SHOW_SBITS(name, gb, num)\
         NEG_SSR32(name##_cache, num)
 # endif
 
 #   define GET_CACHE(name, gb)\
         ((uint32_t)name##_cache)
@@ skipping 244 matching lines @@
 }
 
 static inline void skip_bits1(GetBitContext *s){
     skip_bits(s, 1);
 }
 
 /**
  * reads 0-32 bits.
  */
 static inline unsigned int get_bits_long(GetBitContext *s, int n){
-    if(n<=17) return get_bits(s, n);
+    if(n<=MIN_CACHE_BITS) return get_bits(s, n);
     else{
 #ifdef ALT_BITSTREAM_READER_LE
         int ret= get_bits(s, 16);
         return ret | (get_bits(s, n-16) << 16);
 #else
         int ret= get_bits(s, 16) << (n-16);
         return ret | get_bits(s, n-16);
 #endif
     }
 }
 
 /**
  * reads 0-32 bits as a signed integer.
  */
 static inline int get_sbits_long(GetBitContext *s, int n) {
     return sign_extend(get_bits_long(s, n), n);
 }
 
 /**
  * shows 0-32 bits.
  */
 static inline unsigned int show_bits_long(GetBitContext *s, int n){
-    if(n<=17) return show_bits(s, n);
+    if(n<=MIN_CACHE_BITS) return show_bits(s, n);
     else{
         GetBitContext gb= *s;
         return get_bits_long(&gb, n);
     }
 }
 
 static inline int check_marker(GetBitContext *s, const char *msg)
 {
     int bit= get_bits1(s);
     if(!bit)
@@ skipping 66 matching lines @@
 {\
     static VLC_TYPE table[static_size][2];\
     (vlc)->table= table;\
     (vlc)->table_allocated= static_size;\
     init_vlc(vlc, bits, a,b,c,d,e,f,g, INIT_VLC_USE_NEW_STATIC);\
 }
 
 
 /**
  *
- * if the vlc code is invalid and max_depth=1 than no bits will be removed
- * if the vlc code is invalid and max_depth>1 than the number of bits removed
- * is undefined
+ * If the vlc code is invalid and max_depth=1, then no bits will be removed.
+ * If the vlc code is invalid and max_depth>1, then the number of bits removed
+ * is undefined.
  */
 #define GET_VLC(code, name, gb, table, bits, max_depth)\
 {\
     int n, nb_bits;\
     unsigned int index;\
 \
     index= SHOW_UBITS(name, gb, bits);\
     code = table[index][0];\
     n    = table[index][1];\
 \
@@ skipping 136 matching lines @@
     else
         return 2 - get_bits1(gb);
 }
 
 static inline int get_bits_left(GetBitContext *gb)
 {
     return gb->size_in_bits - get_bits_count(gb);
 }
 
 #endif /* AVCODEC_GET_BITS_H */