cabac: split cabac.h into declarations and function definitions

This fixes standalone compilation of some decoders with --disable-optimizations.
cabac.h defines some inline functions that use symbols from cabac.c.  Without
optimizations these inline functions are not eliminated and linking fails with
references to non-existing symbols.

Splitting the inline functions off into their own header and only #including
it in the places where the inline functions are used allows #including cabac.h
from anywhere without ill effects.

1 files changed, 160 insertions, 0 deletions

diff --git a/libavcodec/cabac_functions.h b/libavcodec/cabac_functions.h
new file mode 100644
index 0000000000..b150aabcc4
--- /dev/null
+++ b/libavcodec/cabac_functions.h
@@ -0,0 +1,160 @@
+/*
+ * H.26L/H.264/AVC/JVT/14496-10/... encoder/decoder
+ * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
+ *
+ * This file is part of Libav.
+ *
+ * Libav 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.
+ *
+ * Libav is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/**
+ * @file
+ * Context Adaptive Binary Arithmetic Coder inline functions
+ */
+
+#ifndef AVCODEC_CABAC_FUNCTIONS_H
+#define AVCODEC_CABAC_FUNCTIONS_H
+
+#include <stdint.h>
+
+#include "cabac.h"
+#include "config.h"
+
+#if ARCH_X86
+#   include "x86/cabac.h"
+#endif
+
+extern const uint8_t ff_h264_norm_shift[512];
+extern uint8_t ff_h264_mlps_state[4*64];
+extern uint8_t ff_h264_lps_range[4*2*64];  ///< rangeTabLPS
+
+static void refill(CABACContext *c){
+#if CABAC_BITS == 16
+        c->low+= (c->bytestream[0]<<9) + (c->bytestream[1]<<1);
+#else
+        c->low+= c->bytestream[0]<<1;
+#endif
+    c->low -= CABAC_MASK;
+    c->bytestream+= CABAC_BITS/8;
+}
+
+static inline void renorm_cabac_decoder_once(CABACContext *c){
+    int shift= (uint32_t)(c->range - 0x100)>>31;
+    c->range<<= shift;
+    c->low  <<= shift;
+    if(!(c->low & CABAC_MASK))
+        refill(c);
+}
+
+#ifndef get_cabac_inline
+static void refill2(CABACContext *c){
+    int i, x;
+
+    x= c->low ^ (c->low-1);
+    i= 7 - ff_h264_norm_shift[x>>(CABAC_BITS-1)];
+
+    x= -CABAC_MASK;
+
+#if CABAC_BITS == 16
+        x+= (c->bytestream[0]<<9) + (c->bytestream[1]<<1);
+#else
+        x+= c->bytestream[0]<<1;
+#endif
+
+    c->low += x<<i;
+    c->bytestream+= CABAC_BITS/8;
+}
+
+static av_always_inline int get_cabac_inline(CABACContext *c, uint8_t * const state){
+    int s = *state;
+    int RangeLPS= ff_h264_lps_range[2*(c->range&0xC0) + s];
+    int bit, lps_mask;
+
+    c->range -= RangeLPS;
+    lps_mask= ((c->range<<(CABAC_BITS+1)) - c->low)>>31;
+
+    c->low -= (c->range<<(CABAC_BITS+1)) & lps_mask;
+    c->range += (RangeLPS - c->range) & lps_mask;
+
+    s^=lps_mask;
+    *state= (ff_h264_mlps_state+128)[s];
+    bit= s&1;
+
+    lps_mask= ff_h264_norm_shift[c->range];
+    c->range<<= lps_mask;
+    c->low  <<= lps_mask;
+    if(!(c->low & CABAC_MASK))
+        refill2(c);
+    return bit;
+}
+#endif
+
+static int av_noinline av_unused get_cabac_noinline(CABACContext *c, uint8_t * const state){
+    return get_cabac_inline(c,state);
+}
+
+static int av_unused get_cabac(CABACContext *c, uint8_t * const state){
+    return get_cabac_inline(c,state);
+}
+
+static int av_unused get_cabac_bypass(CABACContext *c){
+    int range;
+    c->low += c->low;
+
+    if(!(c->low & CABAC_MASK))
+        refill(c);
+
+    range= c->range<<(CABAC_BITS+1);
+    if(c->low < range){
+        return 0;
+    }else{
+        c->low -= range;
+        return 1;
+    }
+}
+
+
+#ifndef get_cabac_bypass_sign
+static av_always_inline int get_cabac_bypass_sign(CABACContext *c, int val){
+    int range, mask;
+    c->low += c->low;
+
+    if(!(c->low & CABAC_MASK))
+        refill(c);
+
+    range= c->range<<(CABAC_BITS+1);
+    c->low -= range;
+    mask= c->low >> 31;
+    range &= mask;
+    c->low += range;
+    return (val^mask)-mask;
+}
+#endif
+
+/**
+ *
+ * @return the number of bytes read or 0 if no end
+ */
+static int av_unused get_cabac_terminate(CABACContext *c){
+    c->range -= 2;
+    if(c->low < c->range<<(CABAC_BITS+1)){
+        renorm_cabac_decoder_once(c);
+        return 0;
+    }else{
+        return c->bytestream - c->bytestream_start;
+    }
+}
+
+#endif /* AVCODEC_CABAC_FUNCTIONS_H */