Clean up cdef_compute_sb_list()

Change-Id: I6abe884340b5b4d186b8901a3c6d65c2f58be3ed
diff --git a/av1/common/cdef.c b/av1/common/cdef.c
index 67602dc..f4a8869 100644
--- a/av1/common/cdef.c
+++ b/av1/common/cdef.c
@@ -33,8 +33,8 @@
   return 1;
 }
 
-int cdef_compute_sb_list(const AV1_COMMON *const cm, int mi_row, int mi_col,
-                         cdef_list *dlist, BLOCK_SIZE bs) {
+int av1_cdef_compute_sb_list(const AV1_COMMON *const cm, int mi_row, int mi_col,
+                             cdef_list *dlist, BLOCK_SIZE bs) {
   MB_MODE_INFO **grid = cm->mi_grid_visible;
   int maxc = cm->mi_cols - mi_col;
   int maxr = cm->mi_rows - mi_row;
@@ -48,16 +48,11 @@
   else
     maxr = AOMMIN(maxr, MI_SIZE_64X64);
 
-  const int r_step = mi_size_high[BLOCK_8X8];
-  const int c_step = mi_size_wide[BLOCK_8X8];
-  const int r_shift = (r_step == 2);
-  const int c_shift = (c_step == 2);
-
-  assert(r_step == 1 || r_step == 2);
-  assert(c_step == 1 || c_step == 2);
-
+  const int r_step = 2;  // mi_size_high[BLOCK_8X8]
+  const int c_step = 2;  // mi_size_wide[BLOCK_8X8]
+  const int r_shift = 1;
+  const int c_shift = 1;
   int count = 0;
-
   for (int r = 0; r < maxr; r += r_step) {
     for (int c = 0; c < maxc; c += c_step) {
       if (!is_8x8_block_skip(grid, mi_row + r, mi_col + c, cm->mi_stride)) {
@@ -227,9 +222,9 @@
       uv_sec_strength += uv_sec_strength == 3;
       if ((level == 0 && sec_strength == 0 && uv_level == 0 &&
            uv_sec_strength == 0) ||
-          (cdef_count = cdef_compute_sb_list(cm, fbr * MI_SIZE_64X64,
-                                             fbc * MI_SIZE_64X64, dlist,
-                                             BLOCK_64X64)) == 0) {
+          (cdef_count = av1_cdef_compute_sb_list(cm, fbr * MI_SIZE_64X64,
+                                                 fbc * MI_SIZE_64X64, dlist,
+                                                 BLOCK_64X64)) == 0) {
         cdef_left = 0;
         continue;
       }
diff --git a/av1/common/cdef.h b/av1/common/cdef.h
index 138e1bf..70bdeaf 100644
--- a/av1/common/cdef.h
+++ b/av1/common/cdef.h
@@ -37,8 +37,8 @@
 extern "C" {
 #endif
 
-int cdef_compute_sb_list(const AV1_COMMON *const cm, int mi_row, int mi_col,
-                         cdef_list *dlist, BLOCK_SIZE bsize);
+int av1_cdef_compute_sb_list(const AV1_COMMON *const cm, int mi_row, int mi_col,
+                             cdef_list *dlist, BLOCK_SIZE bsize);
 void av1_cdef_frame(YV12_BUFFER_CONFIG *frame, AV1_COMMON *cm, MACROBLOCKD *xd);
 
 void av1_cdef_search(YV12_BUFFER_CONFIG *frame, const YV12_BUFFER_CONFIG *ref,
diff --git a/av1/encoder/pickcdef.c b/av1/encoder/pickcdef.c
index 06a4c98..8064bca 100644
--- a/av1/encoder/pickcdef.c
+++ b/av1/encoder/pickcdef.c
@@ -467,7 +467,7 @@
 
       // No filtering if the entire filter block is skipped
       if (sb_all_skip(cm, fbr * MI_SIZE_64X64, fbc * MI_SIZE_64X64)) continue;
-      const int cdef_count = cdef_compute_sb_list(
+      const int cdef_count = av1_cdef_compute_sb_list(
           cm, fbr * MI_SIZE_64X64, fbc * MI_SIZE_64X64, dlist, bs);
 
       int dirinit = 0;