Cleaning up vp9_diamond_search_sad_c() function.

Change-Id: I0816ec12ec0a6f21d0f25f10c214b5fd327afc6c

vp9/encoder/vp9_mcomp.c

@@ -981,66 +981,49 @@ int vp9_diamond_search_sad_c(const MACROBLOCK *x,
                              const vp9_variance_fn_ptr_t *fn_ptr,
                              int *mvjcost, int *mvcost[2],
                              const MV *center_mv) {
-  int i, j, step;
-
   const MACROBLOCKD *const xd = &x->e_mbd;
-  const uint8_t *what = x->plane[0].src.buf;
-  const int what_stride = x->plane[0].src.stride;
-  const uint8_t *in_what;
-  const int in_what_stride = xd->plane[0].pre[0].stride;
-  const uint8_t *best_address;
-
-  int bestsad = INT_MAX;
-  int best_site = 0;
-  int last_site = 0;
-
-  int ref_row, ref_col;
-
+  const struct buf_2d *const what = &x->plane[0].src;
+  const struct buf_2d *const in_what = &xd->plane[0].pre[0];
   // search_param determines the length of the initial step and hence the number
   // of iterations
   // 0 = initial step (MAX_FIRST_STEP) pel : 1 = (MAX_FIRST_STEP/2) pel, 2 =
   // (MAX_FIRST_STEP/4) pel... etc.
   const search_site *const ss = &x->ss[search_param * x->searches_per_step];
   const int tot_steps = (x->ss_count / x->searches_per_step) - search_param;
-
   const MV fcenter_mv = {center_mv->row >> 3, center_mv->col >> 3};
-
   const int *mvjsadcost = x->nmvjointsadcost;
   int *mvsadcost[2] = {x->nmvsadcost[0], x->nmvsadcost[1]};
+  const uint8_t *best_address;
+  int best_sad = INT_MAX;
+  int best_site = 0;
+  int last_site = 0;
+  int i, j, step;
 
   clamp_mv(ref_mv, x->mv_col_min, x->mv_col_max, x->mv_row_min, x->mv_row_max);
-  ref_row = ref_mv->row;
-  ref_col = ref_mv->col;
+  best_address = get_buf_from_mv(in_what, ref_mv);
   *num00 = 0;
-  best_mv->row = ref_row;
-  best_mv->col = ref_col;
-
-  // Work out the start point for the search
-  in_what = xd->plane[0].pre[0].buf + ref_row * in_what_stride + ref_col;
-  best_address = in_what;
+  *best_mv = *ref_mv;
 
   // Check the starting position
-  bestsad = fn_ptr->sdf(what, what_stride, in_what, in_what_stride, 0x7fffffff)
-                + mvsad_err_cost(best_mv, &fcenter_mv,
-                                 mvjsadcost, mvsadcost, sad_per_bit);
+  best_sad = fn_ptr->sdf(what->buf, what->stride,
+                        in_what->buf, in_what->stride, 0x7fffffff) +
+      mvsad_err_cost(best_mv, &fcenter_mv, mvjsadcost, mvsadcost, sad_per_bit);
 
   i = 1;
 
   for (step = 0; step < tot_steps; step++) {
     for (j = 0; j < x->searches_per_step; j++) {
-      const MV this_mv = {best_mv->row + ss[i].mv.row,
-                          best_mv->col + ss[i].mv.col};
-      if (is_mv_in(x, &this_mv)) {
-        const uint8_t *const check_here = ss[i].offset + best_address;
-        int thissad = fn_ptr->sdf(what, what_stride, check_here, in_what_stride,
-                              bestsad);
-
-        if (thissad < bestsad) {
-          thissad += mvsad_err_cost(&this_mv, &fcenter_mv,
-                                    mvjsadcost, mvsadcost, sad_per_bit);
-
-          if (thissad < bestsad) {
-            bestsad = thissad;
+      const MV mv = {best_mv->row + ss[i].mv.row,
+                     best_mv->col + ss[i].mv.col};
+      if (is_mv_in(x, &mv)) {
+       int sad = fn_ptr->sdf(what->buf, what->stride,
+                             best_address + ss[i].offset, in_what->stride,
+                             best_sad);
+        if (sad < best_sad) {
+          sad += mvsad_err_cost(&mv, &fcenter_mv, mvjsadcost, mvsadcost,
+                                sad_per_bit);
+          if (sad < best_sad) {
+            best_sad = sad;
             best_site = i;
           }
         }
@@ -1059,14 +1042,14 @@ int vp9_diamond_search_sad_c(const MACROBLOCK *x,
         const MV this_mv = {best_mv->row + ss[best_site].mv.row,
                             best_mv->col + ss[best_site].mv.col};
         if (is_mv_in(x, &this_mv)) {
-          const uint8_t *const check_here = ss[best_site].offset + best_address;
-          int thissad = fn_ptr->sdf(what, what_stride, check_here,
-                                    in_what_stride, bestsad);
-          if (thissad < bestsad) {
-            thissad += mvsad_err_cost(&this_mv, &fcenter_mv,
-                                      mvjsadcost, mvsadcost, sad_per_bit);
-            if (thissad < bestsad) {
-              bestsad = thissad;
+          int sad = fn_ptr->sdf(what->buf, what->stride,
+                                best_address + ss[best_site].offset,
+                                in_what->stride, best_sad);
+          if (sad < best_sad) {
+            sad += mvsad_err_cost(&this_mv, &fcenter_mv,
+                                  mvjsadcost, mvsadcost, sad_per_bit);
+            if (sad < best_sad) {
+              best_sad = sad;
               best_mv->row += ss[best_site].mv.row;
               best_mv->col += ss[best_site].mv.col;
               best_address += ss[best_site].offset;
@@ -1077,11 +1060,11 @@ int vp9_diamond_search_sad_c(const MACROBLOCK *x,
         break;
       };
 #endif
-    } else if (best_address == in_what) {
+    } else if (best_address == in_what->buf) {
       (*num00)++;
     }
   }
-  return bestsad;
+  return best_sad;
 }
 
 int vp9_diamond_search_sadx4(const MACROBLOCK *x,