Import the aom_read/write_symbol abstractions from aom/master

Change-Id: I0b255c05108c3b97e74df1b59c34111c9e9a5770

aom_dsp/bitreader.h

@@ -104,6 +104,20 @@ static INLINE int aom_read_tree(aom_reader *r, const aom_tree_index *tree,
   return aom_read_tree_bits(r, tree, probs);
 }
 
+static INLINE int aom_read_symbol(aom_reader *r, const aom_cdf_prob *cdf,
+                                  int nsymbs) {
+#if CONFIG_ANS
+  (void)nsymbs;
+  return rans_read(r, cdf);
+#else
+  (void)r;
+  (void)cdf;
+  (void)nsymbs;
+  assert(0 && "Unsupported bitreader operation");
+  return -1;
+#endif
+}
+
 #ifdef __cplusplus
 }  // extern "C"
 #endif

aom_dsp/bitwriter.h

@@ -86,6 +86,24 @@ static INLINE void aom_write_tree(aom_writer *w, const aom_tree_index *tree,
   aom_write_tree_bits(w, tree, probs, bits, len, i);
 }
 
+static INLINE void aom_write_symbol(aom_writer *w, int symb,
+                                    const aom_cdf_prob *cdf, int nsymbs) {
+#if CONFIG_ANS
+  struct rans_sym s;
+  (void)nsymbs;
+  assert(cdf);
+  s.cum_prob = cdf[symb];
+  s.prob = cdf[symb + 1] - s.cum_prob;
+  buf_rans_write(w, &s);
+#else
+  (void)w;
+  (void)symb;
+  (void)cdf;
+  (void)nsymbs;
+  assert(0 && "Unsupported bitwriter operation");
+#endif
+}
+
 #ifdef __cplusplus
 }  // extern "C"
 #endif

aom_dsp/prob.h

@@ -23,6 +23,9 @@ extern "C" {
 
 typedef uint8_t aom_prob;
 
+// TODO(negge): Rename this aom_prob once we remove vpxbool.
+typedef uint16_t aom_cdf_prob;
+
 #define MAX_PROB 255
 
 #define aom_prob_half ((aom_prob)128)

av1/decoder/detokenize.c

@@ -166,7 +166,8 @@ static int decode_coefs(const MACROBLOCKD *xd, PLANE_TYPE type,
     }
 #if CONFIG_ANS
     cdf = &coef_cdfs[band][ctx];
-    token = ONE_TOKEN + rans_read(r, *cdf);
+    token =
+        ONE_TOKEN + aom_read_symbol(r, *cdf, CATEGORY6_TOKEN - ONE_TOKEN + 1);
     INCREMENT_COUNT(ONE_TOKEN + (token > ONE_TOKEN));
     switch (token) {
       case ONE_TOKEN:

av1/encoder/bitstream.c

@@ -657,11 +657,8 @@ static void pack_mb_tokens(aom_writer *w, const TOKENEXTRA **tp,
       aom_write(w, t != ZERO_TOKEN, p->context_tree[1]);
 
       if (t != ZERO_TOKEN) {
-        struct rans_sym s;
-        const rans_lut *token_cdf = p->token_cdf;
-        s.cum_prob = (*token_cdf)[t - ONE_TOKEN];
-        s.prob = (*token_cdf)[t - ONE_TOKEN + 1] - s.cum_prob;
-        buf_rans_write(w, &s);
+        aom_write_symbol(w, t - ONE_TOKEN, *p->token_cdf,
+                         CATEGORY6_TOKEN - ONE_TOKEN + 1);
       }
     }
 #else