[FFmpeg-devel] [PATCH v2 1/2] Move bitswap_32() into a header file.

[Steinar H. Gunderson]

Allows more codecs than mpeg12video to make use of it. Rename to av_bitswap_32()
because it's a public symbol now.
---
 libavcodec/bitstream.c | 14 +++-----------
 libavcodec/mathops.h   |  8 ++++++++
 2 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/libavcodec/bitstream.c b/libavcodec/bitstream.c
index 6c8dca1d85..5d37430540 100644
--- a/libavcodec/bitstream.c
+++ b/libavcodec/bitstream.c
@@ -128,14 +128,6 @@ static int alloc_table(VLC *vlc, int size, int use_static)
     return index;
 }
 
-static av_always_inline uint32_t bitswap_32(uint32_t x)
-{
-    return (uint32_t)ff_reverse[ x        & 0xFF] << 24 |
-           (uint32_t)ff_reverse[(x >> 8)  & 0xFF] << 16 |
-           (uint32_t)ff_reverse[(x >> 16) & 0xFF] << 8  |
-           (uint32_t)ff_reverse[ x >> 24];
-}
-
 typedef struct VLCcode {
     uint8_t bits;
     uint16_t symbol;
@@ -192,7 +184,7 @@ static int build_table(VLC *vlc, int table_nb_bits, int nb_codes,
             nb = 1 << (table_nb_bits - n);
             inc = 1;
             if (flags & INIT_VLC_LE) {
-                j = bitswap_32(code);
+                j = av_bitswap_32(code);
                 inc = 1 << n;
             }
             for (k = 0; k < nb; k++) {
@@ -225,7 +217,7 @@ static int build_table(VLC *vlc, int table_nb_bits, int nb_codes,
                 subtable_bits = FFMAX(subtable_bits, n);
             }
             subtable_bits = FFMIN(subtable_bits, table_nb_bits);
-            j = (flags & INIT_VLC_LE) ? bitswap_32(code_prefix) >> (32 - table_nb_bits) : code_prefix;
+            j = (flags & INIT_VLC_LE) ? av_bitswap_32(code_prefix) >> (32 - table_nb_bits) : code_prefix;
             table[j][1] = -subtable_bits;
             ff_dlog(NULL, "%4x: n=%d (subtable)\n",
                     j, codes[i].bits + table_nb_bits);
@@ -325,7 +317,7 @@ int ff_init_vlc_sparse(VLC *vlc_arg, int nb_bits, int nb_codes,
             return -1;                                                      \
         }                                                                   \
         if (flags & INIT_VLC_LE)                                            \
-            buf[j].code = bitswap_32(buf[j].code);                          \
+            buf[j].code = av_bitswap_32(buf[j].code);                       \
         else                                                                \
             buf[j].code <<= 32 - buf[j].bits;                               \
         if (symbols)                                                        \
diff --git a/libavcodec/mathops.h b/libavcodec/mathops.h
index 5168dc2ce0..65dc8f21f1 100644
--- a/libavcodec/mathops.h
+++ b/libavcodec/mathops.h
@@ -249,4 +249,12 @@ static inline int8_t ff_u8_to_s8(uint8_t a)
     return b.s8;
 }
 
+static av_always_inline uint32_t av_bitswap_32(uint32_t x)
+{
+    return (uint32_t)ff_reverse[ x        & 0xFF] << 24 |
+           (uint32_t)ff_reverse[(x >> 8)  & 0xFF] << 16 |
+           (uint32_t)ff_reverse[(x >> 16) & 0xFF] << 8  |
+           (uint32_t)ff_reverse[ x >> 24];
+}
+
 #endif /* AVCODEC_MATHOPS_H */
-- 
2.11.0