Roll latest libvpx into Android.

Make the VP9 decoding 2X faster than the old one.
Checkout is from master branch(hash:242157c756314827ad9244952c7253e8900b9626).

Change-Id: Ibe67b3ee19f82b87df2416826b63a67f7f79b63a

1 files changed, 378 insertions, 458 deletions

diff --git a/libvpx/vp9/common/vp9_pred_common.c b/libvpx/vp9/common/vp9_pred_common.c
index 17da4f2..e8bcdea 100644
--- a/libvpx/vp9/common/vp9_pred_common.c
+++ b/libvpx/vp9/common/vp9_pred_common.c
@@ -16,505 +16,425 @@
 #include "vp9/common/vp9_seg_common.h"
 #include "vp9/common/vp9_treecoder.h"
 
-// TBD prediction functions for various bitstream signals
-
 // Returns a context number for the given MB prediction signal
-unsigned char vp9_get_pred_context(const VP9_COMMON *const cm,
-                                   const MACROBLOCKD *const xd,
-                                   PRED_ID pred_id) {
+unsigned char vp9_get_pred_context_switchable_interp(const MACROBLOCKD *xd) {
+  const MODE_INFO *const mi = xd->mode_info_context;
+  const MB_MODE_INFO *const above_mbmi = &mi[-xd->mode_info_stride].mbmi;
+  const MB_MODE_INFO *const left_mbmi = &mi[-1].mbmi;
+  const int left_in_image = xd->left_available && left_mbmi->mb_in_image;
+  const int above_in_image = xd->up_available && above_mbmi->mb_in_image;
+  // Note:
+  // The mode info data structure has a one element border above and to the
+  // left of the entries correpsonding to real macroblocks.
+  // The prediction flags in these dummy entries are initialised to 0.
+  // left
+  const int left_mv_pred = is_inter_mode(left_mbmi->mode);
+  const int left_interp = left_in_image && left_mv_pred ?
+          vp9_switchable_interp_map[left_mbmi->interp_filter] :
+          VP9_SWITCHABLE_FILTERS;
+
+  // above
+  const int above_mv_pred = is_inter_mode(above_mbmi->mode);
+  const int above_interp = above_in_image && above_mv_pred ?
+          vp9_switchable_interp_map[above_mbmi->interp_filter] :
+          VP9_SWITCHABLE_FILTERS;
+
+  assert(left_interp != -1);
+  assert(above_interp != -1);
+
+  if (left_interp == above_interp)
+    return left_interp;
+  else if (left_interp == VP9_SWITCHABLE_FILTERS &&
+           above_interp != VP9_SWITCHABLE_FILTERS)
+    return above_interp;
+  else if (left_interp != VP9_SWITCHABLE_FILTERS &&
+           above_interp == VP9_SWITCHABLE_FILTERS)
+    return left_interp;
+  else
+    return VP9_SWITCHABLE_FILTERS;
+}
+// Returns a context number for the given MB prediction signal
+unsigned char vp9_get_pred_context_intra_inter(const MACROBLOCKD *xd) {
   int pred_context;
   const MODE_INFO *const mi = xd->mode_info_context;
-  const MODE_INFO *const above_mi = mi - cm->mode_info_stride;
-  const MODE_INFO *const left_mi = mi - 1;
-  const int left_in_image = xd->left_available && left_mi->mbmi.mb_in_image;
-  const int above_in_image = xd->up_available && above_mi->mbmi.mb_in_image;
+  const MB_MODE_INFO *const above_mbmi = &mi[-xd->mode_info_stride].mbmi;
+  const MB_MODE_INFO *const left_mbmi = &mi[-1].mbmi;
+  const int left_in_image = xd->left_available && left_mbmi->mb_in_image;
+  const int above_in_image = xd->up_available && above_mbmi->mb_in_image;
   // Note:
   // The mode info data structure has a one element border above and to the
   // left of the entries correpsonding to real macroblocks.
   // The prediction flags in these dummy entries are initialised to 0.
-  switch (pred_id) {
-    case PRED_SEG_ID:
-      pred_context = above_mi->mbmi.seg_id_predicted;
-      if (xd->left_available)
-        pred_context += left_mi->mbmi.seg_id_predicted;
-      break;
-
-    case PRED_MBSKIP:
-      pred_context = above_mi->mbmi.mb_skip_coeff;
-      if (xd->left_available)
-        pred_context += left_mi->mbmi.mb_skip_coeff;
-      break;
-
-    case PRED_SWITCHABLE_INTERP: {
-      // left
-      const int left_mv_pred = is_inter_mode(left_mi->mbmi.mode);
-      const int left_interp = left_in_image && left_mv_pred ?
-                    vp9_switchable_interp_map[left_mi->mbmi.interp_filter] :
-                    VP9_SWITCHABLE_FILTERS;
-
-      // above
-      const int above_mv_pred = is_inter_mode(above_mi->mbmi.mode);
-      const int above_interp = above_in_image && above_mv_pred ?
-                    vp9_switchable_interp_map[above_mi->mbmi.interp_filter] :
-                    VP9_SWITCHABLE_FILTERS;
-
-      assert(left_interp != -1);
-      assert(above_interp != -1);
-
-      if (left_interp == above_interp)
-        pred_context = left_interp;
-      else if (left_interp == VP9_SWITCHABLE_FILTERS &&
-               above_interp != VP9_SWITCHABLE_FILTERS)
-         pred_context = above_interp;
-      else if (left_interp != VP9_SWITCHABLE_FILTERS &&
-               above_interp == VP9_SWITCHABLE_FILTERS)
-        pred_context = left_interp;
-      else
-        pred_context = VP9_SWITCHABLE_FILTERS;
-
-      break;
+  if (above_in_image && left_in_image) {  // both edges available
+    if (left_mbmi->ref_frame[0] == INTRA_FRAME &&
+        above_mbmi->ref_frame[0] == INTRA_FRAME) {  // intra/intra (3)
+      pred_context = 3;
+    } else {  // intra/inter (1) or inter/inter (0)
+      pred_context = left_mbmi->ref_frame[0] == INTRA_FRAME ||
+                     above_mbmi->ref_frame[0] == INTRA_FRAME;
     }
+  } else if (above_in_image || left_in_image) {  // one edge available
+    const MB_MODE_INFO *edge_mbmi = above_in_image ? above_mbmi : left_mbmi;
 
-    case PRED_INTRA_INTER: {
-      if (above_in_image && left_in_image) {  // both edges available
-        if (left_mi->mbmi.ref_frame[0] == INTRA_FRAME &&
-            above_mi->mbmi.ref_frame[0] == INTRA_FRAME) {  // intra/intra (3)
-          pred_context = 3;
-        } else {  // intra/inter (1) or inter/inter (0)
-          pred_context = left_mi->mbmi.ref_frame[0] == INTRA_FRAME ||
-                         above_mi->mbmi.ref_frame[0] == INTRA_FRAME;
-        }
-      } else if (above_in_image || left_in_image) {  // one edge available
-        const MODE_INFO *edge = above_in_image ? above_mi : left_mi;
-
-        // inter: 0, intra: 2
-        pred_context = 2 * (edge->mbmi.ref_frame[0] == INTRA_FRAME);
-      } else {
-        pred_context = 0;
-      }
-      assert(pred_context >= 0 && pred_context < INTRA_INTER_CONTEXTS);
-      break;
-    }
+    // inter: 0, intra: 2
+    pred_context = 2 * (edge_mbmi->ref_frame[0] == INTRA_FRAME);
+  } else {
+    pred_context = 0;
+  }
+  assert(pred_context >= 0 && pred_context < INTRA_INTER_CONTEXTS);
+  return pred_context;
+}
+// Returns a context number for the given MB prediction signal
+unsigned char vp9_get_pred_context_comp_inter_inter(const VP9_COMMON *cm,
+                                                    const MACROBLOCKD *xd) {
+  int pred_context;
+  const MODE_INFO *const mi = xd->mode_info_context;
+  const MB_MODE_INFO *const above_mbmi = &mi[-cm->mode_info_stride].mbmi;
+  const MB_MODE_INFO *const left_mbmi = &mi[-1].mbmi;
+  const int left_in_image = xd->left_available && left_mbmi->mb_in_image;
+  const int above_in_image = xd->up_available && above_mbmi->mb_in_image;
+  // Note:
+  // The mode info data structure has a one element border above and to the
+  // left of the entries correpsonding to real macroblocks.
+  // The prediction flags in these dummy entries are initialised to 0.
+  if (above_in_image && left_in_image) {  // both edges available
+    if (above_mbmi->ref_frame[1] <= INTRA_FRAME &&
+        left_mbmi->ref_frame[1] <= INTRA_FRAME)
+      // neither edge uses comp pred (0/1)
+      pred_context = (above_mbmi->ref_frame[0] == cm->comp_fixed_ref) ^
+                     (left_mbmi->ref_frame[0] == cm->comp_fixed_ref);
+    else if (above_mbmi->ref_frame[1] <= INTRA_FRAME)
+      // one of two edges uses comp pred (2/3)
+      pred_context = 2 + (above_mbmi->ref_frame[0] == cm->comp_fixed_ref ||
+                          above_mbmi->ref_frame[0] == INTRA_FRAME);
+    else if (left_mbmi->ref_frame[1] <= INTRA_FRAME)
+      // one of two edges uses comp pred (2/3)
+      pred_context = 2 + (left_mbmi->ref_frame[0] == cm->comp_fixed_ref ||
+                          left_mbmi->ref_frame[0] == INTRA_FRAME);
+    else  // both edges use comp pred (4)
+      pred_context = 4;
+  } else if (above_in_image || left_in_image) {  // one edge available
+    const MB_MODE_INFO *edge_mbmi = above_in_image ? above_mbmi : left_mbmi;
+
+    if (edge_mbmi->ref_frame[1] <= INTRA_FRAME)
+      // edge does not use comp pred (0/1)
+      pred_context = edge_mbmi->ref_frame[0] == cm->comp_fixed_ref;
+    else
+      // edge uses comp pred (3)
+      pred_context = 3;
+  } else {  // no edges available (1)
+    pred_context = 1;
+  }
+  assert(pred_context >= 0 && pred_context < COMP_INTER_CONTEXTS);
+  return pred_context;
+}
 
-    case PRED_COMP_INTER_INTER: {
-      if (above_in_image && left_in_image) {  // both edges available
-        if (above_mi->mbmi.ref_frame[1] <= INTRA_FRAME &&
-            left_mi->mbmi.ref_frame[1] <= INTRA_FRAME) {
-          // neither edge uses comp pred (0/1)
-          pred_context = ((above_mi->mbmi.ref_frame[0] == cm->comp_fixed_ref) ^
-                          (left_mi->mbmi.ref_frame[0] == cm->comp_fixed_ref));
-        } else if (above_mi->mbmi.ref_frame[1] <= INTRA_FRAME) {
-          // one of two edges uses comp pred (2/3)
-          pred_context = 2 +
-              (above_mi->mbmi.ref_frame[0] == cm->comp_fixed_ref ||
-               above_mi->mbmi.ref_frame[0] == INTRA_FRAME);
-        } else if (left_mi->mbmi.ref_frame[1] <= INTRA_FRAME) {
-          // one of two edges uses comp pred (2/3)
-          pred_context = 2 +
-              (left_mi->mbmi.ref_frame[0] == cm->comp_fixed_ref ||
-               left_mi->mbmi.ref_frame[0] == INTRA_FRAME);
-        } else {  // both edges use comp pred (4)
+// Returns a context number for the given MB prediction signal
+unsigned char vp9_get_pred_context_comp_ref_p(const VP9_COMMON *cm,
+                                              const MACROBLOCKD *xd) {
+  int pred_context;
+  const MODE_INFO *const mi = xd->mode_info_context;
+  const MB_MODE_INFO *const above_mbmi = &mi[-cm->mode_info_stride].mbmi;
+  const MB_MODE_INFO *const left_mbmi = &mi[-1].mbmi;
+  const int left_in_image = xd->left_available && left_mbmi->mb_in_image;
+  const int above_in_image = xd->up_available && above_mbmi->mb_in_image;
+  // Note:
+  // The mode info data structure has a one element border above and to the
+  // left of the entries correpsonding to real macroblocks.
+  // The prediction flags in these dummy entries are initialised to 0.
+  const int fix_ref_idx = cm->ref_frame_sign_bias[cm->comp_fixed_ref];
+  const int var_ref_idx = !fix_ref_idx;
+
+  if (above_in_image && left_in_image) {  // both edges available
+    if (above_mbmi->ref_frame[0] == INTRA_FRAME &&
+        left_mbmi->ref_frame[0] == INTRA_FRAME) {  // intra/intra (2)
+      pred_context = 2;
+    } else if (above_mbmi->ref_frame[0] == INTRA_FRAME ||
+               left_mbmi->ref_frame[0] == INTRA_FRAME) {  // intra/inter
+      const MB_MODE_INFO *edge_mbmi = above_mbmi->ref_frame[0] == INTRA_FRAME ?
+                                          left_mbmi : above_mbmi;
+
+      if (edge_mbmi->ref_frame[1] <= INTRA_FRAME)  // single pred (1/3)
+        pred_context = 1 + 2 * (edge_mbmi->ref_frame[0] != cm->comp_var_ref[1]);
+      else  // comp pred (1/3)
+        pred_context = 1 + 2 * (edge_mbmi->ref_frame[var_ref_idx]
+                                    != cm->comp_var_ref[1]);
+    } else {  // inter/inter
+      int l_sg = left_mbmi->ref_frame[1] <= INTRA_FRAME;
+      int a_sg = above_mbmi->ref_frame[1] <= INTRA_FRAME;
+      MV_REFERENCE_FRAME vrfa = a_sg ? above_mbmi->ref_frame[0]
+                                     : above_mbmi->ref_frame[var_ref_idx];
+      MV_REFERENCE_FRAME vrfl = l_sg ? left_mbmi->ref_frame[0]
+                                     : left_mbmi->ref_frame[var_ref_idx];
+
+      if (vrfa == vrfl && cm->comp_var_ref[1] == vrfa) {
+        pred_context = 0;
+      } else if (l_sg && a_sg) {  // single/single
+        if ((vrfa == cm->comp_fixed_ref && vrfl == cm->comp_var_ref[0]) ||
+            (vrfl == cm->comp_fixed_ref && vrfa == cm->comp_var_ref[0]))
           pred_context = 4;
-        }
-      } else if (above_in_image || left_in_image) {  // one edge available
-        const MODE_INFO *edge = above_in_image ? above_mi : left_mi;
-
-        if (edge->mbmi.ref_frame[1] <= INTRA_FRAME) {
-          // edge does not use comp pred (0/1)
-          pred_context = edge->mbmi.ref_frame[0] == cm->comp_fixed_ref;
-        } else {  // edge uses comp pred (3)
+        else if (vrfa == vrfl)
           pred_context = 3;
-        }
-      } else {  // no edges available (1)
-        pred_context = 1;
-      }
-      assert(pred_context >= 0 && pred_context < COMP_INTER_CONTEXTS);
-      break;
-    }
-
-    case PRED_COMP_REF_P: {
-      const int fix_ref_idx = cm->ref_frame_sign_bias[cm->comp_fixed_ref];
-      const int var_ref_idx = !fix_ref_idx;
-
-      if (above_in_image && left_in_image) {  // both edges available
-        if (above_mi->mbmi.ref_frame[0] == INTRA_FRAME &&
-            left_mi->mbmi.ref_frame[0] == INTRA_FRAME) {  // intra/intra (2)
-          pred_context = 2;
-        } else if (above_mi->mbmi.ref_frame[0] == INTRA_FRAME ||
-                   left_mi->mbmi.ref_frame[0] == INTRA_FRAME) {  // intra/inter
-          const MODE_INFO *edge = above_mi->mbmi.ref_frame[0] == INTRA_FRAME ?
-                                  left_mi : above_mi;
-
-          if (edge->mbmi.ref_frame[1] <= INTRA_FRAME) {  // single pred (1/3)
-            pred_context = 1 +
-                2 * edge->mbmi.ref_frame[0] != cm->comp_var_ref[1];
-          } else {  // comp pred (1/3)
-            pred_context = 1 +
-                2 * edge->mbmi.ref_frame[var_ref_idx] != cm->comp_var_ref[1];
-          }
-        } else {  // inter/inter
-          int l_sg = left_mi->mbmi.ref_frame[1] <= INTRA_FRAME;
-          int a_sg = above_mi->mbmi.ref_frame[1] <= INTRA_FRAME;
-          MV_REFERENCE_FRAME vrfa = a_sg ? above_mi->mbmi.ref_frame[0] :
-              above_mi->mbmi.ref_frame[var_ref_idx];
-          MV_REFERENCE_FRAME vrfl = l_sg ? left_mi->mbmi.ref_frame[0] :
-              left_mi->mbmi.ref_frame[var_ref_idx];
-
-          if (vrfa == vrfl && cm->comp_var_ref[1] == vrfa) {
-            pred_context = 0;
-          } else if (l_sg && a_sg) {  // single/single
-            if ((vrfa == cm->comp_fixed_ref && vrfl == cm->comp_var_ref[0]) ||
-                (vrfl == cm->comp_fixed_ref && vrfa == cm->comp_var_ref[0])) {
-              pred_context = 4;
-            } else if (vrfa == vrfl) {
-              pred_context = 3;
-            } else {
-              pred_context = 1;
-            }
-          } else if (l_sg || a_sg) {  // single/comp
-            MV_REFERENCE_FRAME vrfc = l_sg ? vrfa : vrfl;
-            MV_REFERENCE_FRAME rfs = a_sg ? vrfa : vrfl;
-
-            if (vrfc == cm->comp_var_ref[1] && rfs != cm->comp_var_ref[1]) {
-              pred_context = 1;
-            } else if (rfs == cm->comp_var_ref[1] &&
-                       vrfc != cm->comp_var_ref[1]) {
-              pred_context = 2;
-            } else {
-              pred_context = 4;
-            }
-          } else if (vrfa == vrfl) {  // comp/comp
-            pred_context = 4;
-          } else {
-            pred_context = 2;
-          }
-        }
-      } else if (above_in_image || left_in_image) {  // one edge available
-        const MODE_INFO *edge = above_in_image ? above_mi : left_mi;
-
-        if (edge->mbmi.ref_frame[0] == INTRA_FRAME) {
+        else
+          pred_context = 1;
+      } else if (l_sg || a_sg) {  // single/comp
+        MV_REFERENCE_FRAME vrfc = l_sg ? vrfa : vrfl;
+        MV_REFERENCE_FRAME rfs = a_sg ? vrfa : vrfl;
+        if (vrfc == cm->comp_var_ref[1] && rfs != cm->comp_var_ref[1])
+          pred_context = 1;
+        else if (rfs == cm->comp_var_ref[1] && vrfc != cm->comp_var_ref[1])
           pred_context = 2;
-        } else if (edge->mbmi.ref_frame[1] > INTRA_FRAME) {
-          pred_context =
-              4 * edge->mbmi.ref_frame[var_ref_idx] != cm->comp_var_ref[1];
-        } else {
-          pred_context = 3 * edge->mbmi.ref_frame[0] != cm->comp_var_ref[1];
-        }
-      } else {  // no edges available (2)
+        else
+          pred_context = 4;
+      } else if (vrfa == vrfl) {  // comp/comp
+        pred_context = 4;
+      } else {
         pred_context = 2;
       }
-      assert(pred_context >= 0 && pred_context < REF_CONTEXTS);
-      break;
     }
+  } else if (above_in_image || left_in_image) {  // one edge available
+    const MB_MODE_INFO *edge_mbmi = above_in_image ? above_mbmi : left_mbmi;
+
+    if (edge_mbmi->ref_frame[0] == INTRA_FRAME)
+      pred_context = 2;
+    else if (edge_mbmi->ref_frame[1] > INTRA_FRAME)
+      pred_context = 4 * (edge_mbmi->ref_frame[var_ref_idx]
+                              != cm->comp_var_ref[1]);
+    else
+      pred_context = 3 * (edge_mbmi->ref_frame[0] != cm->comp_var_ref[1]);
+  } else {  // no edges available (2)
+    pred_context = 2;
+  }
+  assert(pred_context >= 0 && pred_context < REF_CONTEXTS);
 
-    case PRED_SINGLE_REF_P1: {
-      if (above_in_image && left_in_image) {  // both edges available
-        if (above_mi->mbmi.ref_frame[0] == INTRA_FRAME &&
-            left_mi->mbmi.ref_frame[0] == INTRA_FRAME) {
-          pred_context = 2;
-        } else if (above_mi->mbmi.ref_frame[0] == INTRA_FRAME ||
-                   left_mi->mbmi.ref_frame[0] == INTRA_FRAME) {
-          const MODE_INFO *edge = above_mi->mbmi.ref_frame[0] == INTRA_FRAME ?
-                                  left_mi : above_mi;
-
-          if (edge->mbmi.ref_frame[1] <= INTRA_FRAME) {
-            pred_context = 4 * (edge->mbmi.ref_frame[0] == LAST_FRAME);
-          } else {
-            pred_context = 1 + (edge->mbmi.ref_frame[0] == LAST_FRAME ||
-                                edge->mbmi.ref_frame[1] == LAST_FRAME);
-          }
-        } else if (above_mi->mbmi.ref_frame[1] <= INTRA_FRAME &&
-                   left_mi->mbmi.ref_frame[1] <= INTRA_FRAME) {
-          pred_context = 2 * (above_mi->mbmi.ref_frame[0] == LAST_FRAME) +
-                         2 * (left_mi->mbmi.ref_frame[0] == LAST_FRAME);
-        } else if (above_mi->mbmi.ref_frame[1] > INTRA_FRAME &&
-                   left_mi->mbmi.ref_frame[1] > INTRA_FRAME) {
-          pred_context = 1 + (above_mi->mbmi.ref_frame[0] == LAST_FRAME ||
-                              above_mi->mbmi.ref_frame[1] == LAST_FRAME ||
-                              left_mi->mbmi.ref_frame[0] == LAST_FRAME ||
-                              left_mi->mbmi.ref_frame[1] == LAST_FRAME);
-        } else {
-          MV_REFERENCE_FRAME rfs = above_mi->mbmi.ref_frame[1] <= INTRA_FRAME ?
-              above_mi->mbmi.ref_frame[0] : left_mi->mbmi.ref_frame[0];
-          MV_REFERENCE_FRAME crf1 = above_mi->mbmi.ref_frame[1] > INTRA_FRAME ?
-              above_mi->mbmi.ref_frame[0] : left_mi->mbmi.ref_frame[0];
-          MV_REFERENCE_FRAME crf2 = above_mi->mbmi.ref_frame[1] > INTRA_FRAME ?
-              above_mi->mbmi.ref_frame[1] : left_mi->mbmi.ref_frame[1];
-
-          if (rfs == LAST_FRAME) {
-            pred_context = 3 + (crf1 == LAST_FRAME || crf2 == LAST_FRAME);
-          } else {
-            pred_context = crf1 == LAST_FRAME || crf2 == LAST_FRAME;
-          }
-        }
-      } else if (above_in_image || left_in_image) {  // one edge available
-        const MODE_INFO *edge = above_in_image ? above_mi : left_mi;
-
-        if (edge->mbmi.ref_frame[0] == INTRA_FRAME) {
-          pred_context = 2;
-        } else if (edge->mbmi.ref_frame[1] <= INTRA_FRAME) {
-          pred_context = 4 * (edge->mbmi.ref_frame[0] == LAST_FRAME);
-        } else {
-          pred_context = 1 + (edge->mbmi.ref_frame[0] == LAST_FRAME ||
-                              edge->mbmi.ref_frame[1] == LAST_FRAME);
-        }
-      } else {  // no edges available (2)
-        pred_context = 2;
-      }
-      assert(pred_context >= 0 && pred_context < REF_CONTEXTS);
-      break;
+  return pred_context;
+}
+unsigned char vp9_get_pred_context_single_ref_p1(const MACROBLOCKD *xd) {
+  int pred_context;
+  const MODE_INFO *const mi = xd->mode_info_context;
+  const MB_MODE_INFO *const above_mbmi = &mi[-xd->mode_info_stride].mbmi;
+  const MB_MODE_INFO *const left_mbmi = &mi[-1].mbmi;
+  const int left_in_image = xd->left_available && left_mbmi->mb_in_image;
+  const int above_in_image = xd->up_available && above_mbmi->mb_in_image;
+  // Note:
+  // The mode info data structure has a one element border above and to the
+  // left of the entries correpsonding to real macroblocks.
+  // The prediction flags in these dummy entries are initialised to 0.
+  if (above_in_image && left_in_image) {  // both edges available
+    if (above_mbmi->ref_frame[0] == INTRA_FRAME &&
+        left_mbmi->ref_frame[0] == INTRA_FRAME) {
+      pred_context = 2;
+    } else if (above_mbmi->ref_frame[0] == INTRA_FRAME ||
+               left_mbmi->ref_frame[0] == INTRA_FRAME) {
+      const MB_MODE_INFO *edge_mbmi = above_mbmi->ref_frame[0] == INTRA_FRAME ?
+                                          left_mbmi : above_mbmi;
+
+      if (edge_mbmi->ref_frame[1] <= INTRA_FRAME)
+        pred_context = 4 * (edge_mbmi->ref_frame[0] == LAST_FRAME);
+      else
+        pred_context = 1 + (edge_mbmi->ref_frame[0] == LAST_FRAME ||
+                            edge_mbmi->ref_frame[1] == LAST_FRAME);
+    } else if (above_mbmi->ref_frame[1] <= INTRA_FRAME &&
+               left_mbmi->ref_frame[1] <= INTRA_FRAME) {
+      pred_context = 2 * (above_mbmi->ref_frame[0] == LAST_FRAME) +
+                     2 * (left_mbmi->ref_frame[0] == LAST_FRAME);
+    } else if (above_mbmi->ref_frame[1] > INTRA_FRAME &&
+               left_mbmi->ref_frame[1] > INTRA_FRAME) {
+      pred_context = 1 + (above_mbmi->ref_frame[0] == LAST_FRAME ||
+                          above_mbmi->ref_frame[1] == LAST_FRAME ||
+                          left_mbmi->ref_frame[0] == LAST_FRAME ||
+                          left_mbmi->ref_frame[1] == LAST_FRAME);
+    } else {
+      MV_REFERENCE_FRAME rfs = above_mbmi->ref_frame[1] <= INTRA_FRAME ?
+              above_mbmi->ref_frame[0] : left_mbmi->ref_frame[0];
+      MV_REFERENCE_FRAME crf1 = above_mbmi->ref_frame[1] > INTRA_FRAME ?
+              above_mbmi->ref_frame[0] : left_mbmi->ref_frame[0];
+      MV_REFERENCE_FRAME crf2 = above_mbmi->ref_frame[1] > INTRA_FRAME ?
+              above_mbmi->ref_frame[1] : left_mbmi->ref_frame[1];
+
+      if (rfs == LAST_FRAME)
+        pred_context = 3 + (crf1 == LAST_FRAME || crf2 == LAST_FRAME);
+      else
+        pred_context = crf1 == LAST_FRAME || crf2 == LAST_FRAME;
     }
+  } else if (above_in_image || left_in_image) {  // one edge available
+    const MB_MODE_INFO *edge_mbmi = above_in_image ? above_mbmi : left_mbmi;
+
+    if (edge_mbmi->ref_frame[0] == INTRA_FRAME)
+      pred_context = 2;
+    else if (edge_mbmi->ref_frame[1] <= INTRA_FRAME)
+      pred_context = 4 * (edge_mbmi->ref_frame[0] == LAST_FRAME);
+    else
+      pred_context = 1 + (edge_mbmi->ref_frame[0] == LAST_FRAME ||
+                          edge_mbmi->ref_frame[1] == LAST_FRAME);
+  } else {  // no edges available (2)
+    pred_context = 2;
+  }
+  assert(pred_context >= 0 && pred_context < REF_CONTEXTS);
+  return pred_context;
+}
 
-    case PRED_SINGLE_REF_P2: {
-      if (above_in_image && left_in_image) {  // both edges available
-        if (above_mi->mbmi.ref_frame[0] == INTRA_FRAME &&
-            left_mi->mbmi.ref_frame[0] == INTRA_FRAME) {
-          pred_context = 2;
-        } else if (above_mi->mbmi.ref_frame[0] == INTRA_FRAME ||
-                   left_mi->mbmi.ref_frame[0] == INTRA_FRAME) {
-          const MODE_INFO *edge = above_mi->mbmi.ref_frame[0] == INTRA_FRAME ?
-                                  left_mi : above_mi;
-
-          if (edge->mbmi.ref_frame[1] <= INTRA_FRAME) {
-            if (edge->mbmi.ref_frame[0] == LAST_FRAME) {
-              pred_context = 3;
-            } else {
-              pred_context = 4 * (edge->mbmi.ref_frame[0] == GOLDEN_FRAME);
-            }
-          } else {
-            pred_context = 1 + 2 * (edge->mbmi.ref_frame[0] == GOLDEN_FRAME ||
-                                    edge->mbmi.ref_frame[1] == GOLDEN_FRAME);
-          }
-        } else if (above_mi->mbmi.ref_frame[1] <= INTRA_FRAME &&
-                   left_mi->mbmi.ref_frame[1] <= INTRA_FRAME) {
-          if (above_mi->mbmi.ref_frame[0] == LAST_FRAME &&
-              left_mi->mbmi.ref_frame[0] == LAST_FRAME) {
-            pred_context = 3;
-          } else if (above_mi->mbmi.ref_frame[0] == LAST_FRAME ||
-                     left_mi->mbmi.ref_frame[0] == LAST_FRAME) {
-            const MODE_INFO *edge = above_mi->mbmi.ref_frame[0] == LAST_FRAME ?
-                                    left_mi : above_mi;
-
-            pred_context = 4 * (edge->mbmi.ref_frame[0] == GOLDEN_FRAME);
-          } else {
-            pred_context = 2 * (above_mi->mbmi.ref_frame[0] == GOLDEN_FRAME) +
-                           2 * (left_mi->mbmi.ref_frame[0] == GOLDEN_FRAME);
-          }
-        } else if (above_mi->mbmi.ref_frame[1] > INTRA_FRAME &&
-                   left_mi->mbmi.ref_frame[1] > INTRA_FRAME) {
-          if (above_mi->mbmi.ref_frame[0] == left_mi->mbmi.ref_frame[0] &&
-              above_mi->mbmi.ref_frame[1] == left_mi->mbmi.ref_frame[1]) {
-            pred_context = 3 * (above_mi->mbmi.ref_frame[0] == GOLDEN_FRAME ||
-                                above_mi->mbmi.ref_frame[1] == GOLDEN_FRAME ||
-                                left_mi->mbmi.ref_frame[0] == GOLDEN_FRAME ||
-                                left_mi->mbmi.ref_frame[1] == GOLDEN_FRAME);
-          } else {
-            pred_context = 2;
-          }
-        } else {
-          MV_REFERENCE_FRAME rfs = above_mi->mbmi.ref_frame[1] <= INTRA_FRAME ?
-              above_mi->mbmi.ref_frame[0] : left_mi->mbmi.ref_frame[0];
-          MV_REFERENCE_FRAME crf1 = above_mi->mbmi.ref_frame[1] > INTRA_FRAME ?
-              above_mi->mbmi.ref_frame[0] : left_mi->mbmi.ref_frame[0];
-          MV_REFERENCE_FRAME crf2 = above_mi->mbmi.ref_frame[1] > INTRA_FRAME ?
-              above_mi->mbmi.ref_frame[1] : left_mi->mbmi.ref_frame[1];
-
-          if (rfs == GOLDEN_FRAME) {
-            pred_context = 3 + (crf1 == GOLDEN_FRAME || crf2 == GOLDEN_FRAME);
-          } else if (rfs == ALTREF_FRAME) {
-            pred_context = crf1 == GOLDEN_FRAME || crf2 == GOLDEN_FRAME;
-          } else {
-            pred_context =
-                1 + 2 * (crf1 == GOLDEN_FRAME || crf2 == GOLDEN_FRAME);
-          }
-        }
-      } else if (above_in_image || left_in_image) {  // one edge available
-        const MODE_INFO *edge = above_in_image ? above_mi : left_mi;
-
-        if (edge->mbmi.ref_frame[0] == INTRA_FRAME ||
-            (edge->mbmi.ref_frame[0] == LAST_FRAME &&
-             edge->mbmi.ref_frame[1] <= INTRA_FRAME)) {
-          pred_context = 2;
-        } else if (edge->mbmi.ref_frame[1] <= INTRA_FRAME) {
-          pred_context = 4 * (edge->mbmi.ref_frame[0] == GOLDEN_FRAME);
-        } else {
-          pred_context = 3 * (edge->mbmi.ref_frame[0] == GOLDEN_FRAME ||
-                              edge->mbmi.ref_frame[1] == GOLDEN_FRAME);
-        }
-      } else {  // no edges available (2)
-        pred_context = 2;
-      }
-      assert(pred_context >= 0 && pred_context < REF_CONTEXTS);
-      break;
-    }
+unsigned char vp9_get_pred_context_single_ref_p2(const MACROBLOCKD *xd) {
+  int pred_context;
+  const MODE_INFO *const mi = xd->mode_info_context;
+  const MB_MODE_INFO *const above_mbmi = &mi[-xd->mode_info_stride].mbmi;
+  const MB_MODE_INFO *const left_mbmi = &mi[-1].mbmi;
+  const int left_in_image = xd->left_available && left_mbmi->mb_in_image;
+  const int above_in_image = xd->up_available && above_mbmi->mb_in_image;
 
-    case PRED_TX_SIZE: {
-      int above_context, left_context;
-      int max_tx_size;
-      if (mi->mbmi.sb_type < BLOCK_SIZE_SB8X8)
-        max_tx_size = TX_4X4;
-      else if (mi->mbmi.sb_type < BLOCK_SIZE_MB16X16)
-        max_tx_size = TX_8X8;
-      else if (mi->mbmi.sb_type < BLOCK_SIZE_SB32X32)
-        max_tx_size = TX_16X16;
-      else
-        max_tx_size = TX_32X32;
-      above_context = left_context = max_tx_size;
-      if (above_in_image) {
-        above_context = (above_mi->mbmi.mb_skip_coeff ?
-                         max_tx_size : above_mi->mbmi.txfm_size);
-      }
-      if (left_in_image) {
-        left_context = (left_mi->mbmi.mb_skip_coeff ?
-                        max_tx_size : left_mi->mbmi.txfm_size);
-      }
-      if (!left_in_image) {
-        left_context = above_context;
+  // Note:
+  // The mode info data structure has a one element border above and to the
+  // left of the entries correpsonding to real macroblocks.
+  // The prediction flags in these dummy entries are initialised to 0.
+  if (above_in_image && left_in_image) {  // both edges available
+    if (above_mbmi->ref_frame[0] == INTRA_FRAME &&
+        left_mbmi->ref_frame[0] == INTRA_FRAME) {
+      pred_context = 2;
+    } else if (above_mbmi->ref_frame[0] == INTRA_FRAME ||
+               left_mbmi->ref_frame[0] == INTRA_FRAME) {
+      const MB_MODE_INFO *edge_mbmi = above_mbmi->ref_frame[0] == INTRA_FRAME ?
+                                          left_mbmi : above_mbmi;
+
+      if (edge_mbmi->ref_frame[1] <= INTRA_FRAME) {
+        if (edge_mbmi->ref_frame[0] == LAST_FRAME)
+          pred_context = 3;
+        else
+          pred_context = 4 * (edge_mbmi->ref_frame[0] == GOLDEN_FRAME);
+      } else {
+        pred_context = 1 + 2 * (edge_mbmi->ref_frame[0] == GOLDEN_FRAME ||
+                                edge_mbmi->ref_frame[1] == GOLDEN_FRAME);
       }
-      if (!above_in_image) {
-        above_context = left_context;
+    } else if (above_mbmi->ref_frame[1] <= INTRA_FRAME &&
+               left_mbmi->ref_frame[1] <= INTRA_FRAME) {
+      if (above_mbmi->ref_frame[0] == LAST_FRAME &&
+          left_mbmi->ref_frame[0] == LAST_FRAME) {
+        pred_context = 3;
+      } else if (above_mbmi->ref_frame[0] == LAST_FRAME ||
+                 left_mbmi->ref_frame[0] == LAST_FRAME) {
+        const MB_MODE_INFO *edge_mbmi = above_mbmi->ref_frame[0] == LAST_FRAME ?
+                                           left_mbmi : above_mbmi;
+
+        pred_context = 4 * (edge_mbmi->ref_frame[0] == GOLDEN_FRAME);
+      } else {
+        pred_context = 2 * (above_mbmi->ref_frame[0] == GOLDEN_FRAME) +
+                       2 * (left_mbmi->ref_frame[0] == GOLDEN_FRAME);
       }
-      pred_context = (above_context + left_context > max_tx_size);
-      break;
+    } else if (above_mbmi->ref_frame[1] > INTRA_FRAME &&
+               left_mbmi->ref_frame[1] > INTRA_FRAME) {
+      if (above_mbmi->ref_frame[0] == left_mbmi->ref_frame[0] &&
+          above_mbmi->ref_frame[1] == left_mbmi->ref_frame[1])
+        pred_context = 3 * (above_mbmi->ref_frame[0] == GOLDEN_FRAME ||
+                            above_mbmi->ref_frame[1] == GOLDEN_FRAME ||
+                            left_mbmi->ref_frame[0] == GOLDEN_FRAME ||
+                            left_mbmi->ref_frame[1] == GOLDEN_FRAME);
+      else
+        pred_context = 2;
+    } else {
+      MV_REFERENCE_FRAME rfs = above_mbmi->ref_frame[1] <= INTRA_FRAME ?
+              above_mbmi->ref_frame[0] : left_mbmi->ref_frame[0];
+      MV_REFERENCE_FRAME crf1 = above_mbmi->ref_frame[1] > INTRA_FRAME ?
+              above_mbmi->ref_frame[0] : left_mbmi->ref_frame[0];
+      MV_REFERENCE_FRAME crf2 = above_mbmi->ref_frame[1] > INTRA_FRAME ?
+              above_mbmi->ref_frame[1] : left_mbmi->ref_frame[1];
+
+      if (rfs == GOLDEN_FRAME)
+        pred_context = 3 + (crf1 == GOLDEN_FRAME || crf2 == GOLDEN_FRAME);
+      else if (rfs == ALTREF_FRAME)
+        pred_context = crf1 == GOLDEN_FRAME || crf2 == GOLDEN_FRAME;
+      else
+        pred_context = 1 + 2 * (crf1 == GOLDEN_FRAME || crf2 == GOLDEN_FRAME);
     }
-
-    default:
-      assert(0);
-      pred_context = 0;  // *** add error trap code.
-      break;
+  } else if (above_in_image || left_in_image) {  // one edge available
+    const MB_MODE_INFO *edge_mbmi = above_in_image ? above_mbmi : left_mbmi;
+
+    if (edge_mbmi->ref_frame[0] == INTRA_FRAME ||
+        (edge_mbmi->ref_frame[0] == LAST_FRAME &&
+         edge_mbmi->ref_frame[1] <= INTRA_FRAME))
+      pred_context = 2;
+    else if (edge_mbmi->ref_frame[1] <= INTRA_FRAME)
+      pred_context = 4 * (edge_mbmi->ref_frame[0] == GOLDEN_FRAME);
+    else
+      pred_context = 3 * (edge_mbmi->ref_frame[0] == GOLDEN_FRAME ||
+                          edge_mbmi->ref_frame[1] == GOLDEN_FRAME);
+  } else {  // no edges available (2)
+    pred_context = 2;
   }
-
+  assert(pred_context >= 0 && pred_context < REF_CONTEXTS);
   return pred_context;
 }
-
-// This function returns a context probability for coding a given
-// prediction signal
-vp9_prob vp9_get_pred_prob(const VP9_COMMON *const cm,
-                          const MACROBLOCKD *const xd,
-                          PRED_ID pred_id) {
-  const int pred_context = vp9_get_pred_context(cm, xd, pred_id);
-
-  switch (pred_id) {
-    case PRED_SEG_ID:
-      return cm->segment_pred_probs[pred_context];
-    case PRED_MBSKIP:
-      return cm->fc.mbskip_probs[pred_context];
-    case PRED_INTRA_INTER:
-      return cm->fc.intra_inter_prob[pred_context];
-    case PRED_COMP_INTER_INTER:
-      return cm->fc.comp_inter_prob[pred_context];
-    case PRED_COMP_REF_P:
-      return cm->fc.comp_ref_prob[pred_context];
-    case PRED_SINGLE_REF_P1:
-      return cm->fc.single_ref_prob[pred_context][0];
-    case PRED_SINGLE_REF_P2:
-      return cm->fc.single_ref_prob[pred_context][1];
-    default:
-      assert(0);
-      return 128;  // *** add error trap code.
-  }
-}
-
-// This function returns a context probability ptr for coding a given
-// prediction signal
-const vp9_prob *vp9_get_pred_probs(const VP9_COMMON *const cm,
-                                   const MACROBLOCKD *const xd,
-                                   PRED_ID pred_id) {
+// Returns a context number for the given MB prediction signal
+// The mode info data structure has a one element border above and to the
+// left of the entries corresponding to real blocks.
+// The prediction flags in these dummy entries are initialized to 0.
+unsigned char vp9_get_pred_context_tx_size(const MACROBLOCKD *xd) {
   const MODE_INFO *const mi = xd->mode_info_context;
-  const int pred_context = vp9_get_pred_context(cm, xd, pred_id);
+  const MB_MODE_INFO *const above_mbmi = &mi[-xd->mode_info_stride].mbmi;
+  const MB_MODE_INFO *const left_mbmi = &mi[-1].mbmi;
+  const int left_in_image = xd->left_available && left_mbmi->mb_in_image;
+  const int above_in_image = xd->up_available && above_mbmi->mb_in_image;
+  const int max_tx_size = max_txsize_lookup[mi->mbmi.sb_type];
+  int above_context = max_tx_size;
+  int left_context = max_tx_size;
 
-  switch (pred_id) {
-    case PRED_SWITCHABLE_INTERP:
-      return &cm->fc.switchable_interp_prob[pred_context][0];
+  if (above_in_image)
+    above_context = above_mbmi->mb_skip_coeff ? max_tx_size
+                                              : above_mbmi->txfm_size;
 
-    case PRED_TX_SIZE:
-      if (mi->mbmi.sb_type < BLOCK_SIZE_MB16X16)
-        return cm->fc.tx_probs_8x8p[pred_context];
-      else if (mi->mbmi.sb_type < BLOCK_SIZE_SB32X32)
-        return cm->fc.tx_probs_16x16p[pred_context];
-      else
-        return cm->fc.tx_probs_32x32p[pred_context];
+  if (left_in_image)
+    left_context = left_mbmi->mb_skip_coeff ? max_tx_size
+                                            : left_mbmi->txfm_size;
 
-    default:
-      assert(0);
-      return NULL;  // *** add error trap code.
-  }
-}
+  if (!left_in_image)
+    left_context = above_context;
 
-// This function returns the status of the given prediction signal.
-// I.e. is the predicted value for the given signal correct.
-unsigned char vp9_get_pred_flag(const MACROBLOCKD *const xd,
-                                PRED_ID pred_id) {
-  switch (pred_id) {
-    case PRED_SEG_ID:
-      return xd->mode_info_context->mbmi.seg_id_predicted;
-    case PRED_MBSKIP:
-      return xd->mode_info_context->mbmi.mb_skip_coeff;
-    default:
-      assert(0);
-      return 0;  // *** add error trap code.
-  }
+  if (!above_in_image)
+    above_context = left_context;
+
+  return above_context + left_context > max_tx_size;
 }
 
-// This function sets the status of the given prediction signal.
-// I.e. is the predicted value for the given signal correct.
-void vp9_set_pred_flag(MACROBLOCKD *const xd,
-                       PRED_ID pred_id,
-                       unsigned char pred_flag) {
-  const int mis = xd->mode_info_stride;
-  BLOCK_SIZE_TYPE bsize = xd->mode_info_context->mbmi.sb_type;
-  const int bh = 1 << mi_height_log2(bsize);
+void vp9_set_pred_flag_seg_id(VP9_COMMON *cm, BLOCK_SIZE_TYPE bsize,
+                              int mi_row, int mi_col, uint8_t pred_flag) {
+  MODE_INFO *mi = &cm->mi[mi_row * cm->mode_info_stride + mi_col];
   const int bw = 1 << mi_width_log2(bsize);
-#define sub(a, b) (b) < 0 ? (a) + (b) : (a)
-  const int x_mis = sub(bw, xd->mb_to_right_edge >> (3 + LOG2_MI_SIZE));
-  const int y_mis = sub(bh, xd->mb_to_bottom_edge >> (3 + LOG2_MI_SIZE));
-#undef sub
+  const int bh = 1 << mi_height_log2(bsize);
+  const int xmis = MIN(cm->mi_cols - mi_col, bw);
+  const int ymis = MIN(cm->mi_rows - mi_row, bh);
   int x, y;
 
-  switch (pred_id) {
-    case PRED_SEG_ID:
-      for (y = 0; y < y_mis; y++) {
-        for (x = 0; x < x_mis; x++) {
-          xd->mode_info_context[y * mis + x].mbmi.seg_id_predicted = pred_flag;
-        }
-      }
-      break;
-
-    case PRED_MBSKIP:
-      for (y = 0; y < y_mis; y++) {
-        for (x = 0; x < x_mis; x++) {
-          xd->mode_info_context[y * mis + x].mbmi.mb_skip_coeff = pred_flag;
-        }
-      }
-      break;
-
-    default:
-      assert(0);
-      // *** add error trap code.
-      break;
-  }
+  for (y = 0; y < ymis; y++)
+    for (x = 0; x < xmis; x++)
+      mi[y * cm->mode_info_stride + x].mbmi.seg_id_predicted = pred_flag;
 }
 
+void vp9_set_pred_flag_mbskip(VP9_COMMON *cm, BLOCK_SIZE_TYPE bsize,
+                              int mi_row, int mi_col, uint8_t pred_flag) {
+  MODE_INFO *mi = &cm->mi[mi_row * cm->mode_info_stride + mi_col];
+  const int bw = 1 << mi_width_log2(bsize);
+  const int bh = 1 << mi_height_log2(bsize);
+  const int xmis = MIN(cm->mi_cols - mi_col, bw);
+  const int ymis = MIN(cm->mi_rows - mi_row, bh);
+  int x, y;
 
-// The following contain the guts of the prediction code used to
-// peredict various bitstream signals.
+  for (y = 0; y < ymis; y++)
+    for (x = 0; x < xmis; x++)
+      mi[y * cm->mode_info_stride + x].mbmi.mb_skip_coeff = pred_flag;
+}
 
-// Macroblock segment id prediction function
-int vp9_get_pred_mi_segid(VP9_COMMON *cm, BLOCK_SIZE_TYPE sb_type,
-                          int mi_row, int mi_col) {
-  const int mi_index = mi_row * cm->mi_cols + mi_col;
-  const int bw = 1 << mi_width_log2(sb_type);
-  const int bh = 1 << mi_height_log2(sb_type);
-  const int ymis = MIN(cm->mi_rows - mi_row, bh);
+int vp9_get_segment_id(VP9_COMMON *cm, const uint8_t *segment_ids,
+                       BLOCK_SIZE_TYPE bsize, int mi_row, int mi_col) {
+  const int mi_offset = mi_row * cm->mi_cols + mi_col;
+  const int bw = 1 << mi_width_log2(bsize);
+  const int bh = 1 << mi_height_log2(bsize);
   const int xmis = MIN(cm->mi_cols - mi_col, bw);
-  int segment_id = INT_MAX;
-  int x, y;
+  const int ymis = MIN(cm->mi_rows - mi_row, bh);
+  int x, y, segment_id = INT_MAX;
 
-  for (y = 0; y < ymis; y++) {
-    for (x = 0; x < xmis; x++) {
-      const int index = mi_index + (y * cm->mi_cols + x);
-      segment_id = MIN(segment_id, cm->last_frame_seg_map[index]);
-    }
-  }
+  for (y = 0; y < ymis; y++)
+    for (x = 0; x < xmis; x++)
+      segment_id = MIN(segment_id,
+                       segment_ids[mi_offset + y * cm->mi_cols + x]);
+
+  assert(segment_id >= 0 && segment_id < MAX_SEGMENTS);
   return segment_id;
 }