[mip] Fix error which caused asan CI test to fail. Was caused by an uninitialized intra CU mip value.

src/search.c

@@ -161,6 +161,8 @@ static void lcu_fill_cu_info(lcu_t *lcu, int x_local, int y_local, int width, in
         to->intra.mode        = cu->intra.mode;
         to->intra.mode_chroma = cu->intra.mode_chroma;
         to->intra.multi_ref_idx = cu->intra.multi_ref_idx;
+        to->intra.mip_flag = cu->intra.mip_flag;
+        to->intra.mip_is_transposed = cu->intra.mip_is_transposed;
       } else {
         to->skipped   = cu->skipped;
         to->merged    = cu->merged;
@@ -728,8 +730,8 @@ static double search_cu(encoder_state_t * const state, int x, int y, int depth,
       int8_t intra_trafo;
       double intra_cost;
       uint8_t multi_ref_index = 0;
-      bool mip_flag;
+      bool mip_flag = false;
-      bool mip_transposed;
+      bool mip_transposed = false;
       kvz_search_cu_intra(state, x, y, depth, lcu,
                           &intra_mode, &intra_trafo, &intra_cost, &multi_ref_index, &mip_flag, &mip_transposed);
       if (intra_cost < cost) {
@@ -754,7 +756,10 @@ static double search_cu(encoder_state_t * const state, int x, int y, int depth,
     // mode search of adjacent CUs.
     if (cur_cu->type == CU_INTRA) {
       assert(cur_cu->part_size == SIZE_2Nx2N || cur_cu->part_size == SIZE_NxN);
+      // Chroma mode must be planar if mip_flag is set.
+      if (!cur_cu->intra.mip_flag) {
         cur_cu->intra.mode_chroma = cur_cu->intra.mode;
+      }
       lcu_fill_cu_info(lcu, x_local, y_local, cu_width, cu_width, cur_cu);
       kvz_intra_recon_cu(state,
                          x, y,

src/search_intra.c

@@ -829,10 +829,15 @@ static int8_t search_intra_rdo(encoder_state_t * const state,
   }
 
   // Update order according to new costs
+  kvz_sort_modes_intra_luma(modes, trafo, costs, modes_to_check);
+  bool use_mip = false;
   if (num_mip_modes) {
     kvz_sort_modes_intra_luma(mip_modes, mip_trafo, mip_costs, num_mip_modes);
+    if (costs[0] > mip_costs[0]) {
+      use_mip = true;
     }
-  kvz_sort_modes_intra_luma(modes, trafo, costs, modes_to_check);
+  }
+  
 
   // The best transform split hierarchy is not saved anywhere, so to get the
   // transform split hierarchy the search has to be performed again with the
@@ -842,9 +847,25 @@ static int8_t search_intra_rdo(encoder_state_t * const state,
     pred_cu.depth = depth;
     pred_cu.type = CU_INTRA;
     pred_cu.part_size = ((depth == MAX_PU_DEPTH) ? SIZE_NxN : SIZE_2Nx2N);
+    if (use_mip) {
+      pred_cu.intra.mode = mip_modes[0];
+      pred_cu.intra.mode_chroma = 0;
+      pred_cu.intra.multi_ref_idx = 0;
+      int transp_off = num_mip_modes >> 1;
+      bool is_transposed = (mip_modes[0] >= transp_off ? true : false);
+      int8_t pred_mode = (is_transposed ? mip_modes[0] - transp_off : mip_modes[0]);
+      pred_cu.intra.mode = pred_mode;
+      pred_cu.intra.mode_chroma = 0;
+      pred_cu.intra.mip_flag = true;
+      pred_cu.intra.mip_is_transposed = is_transposed;
+    }
+    else {
       pred_cu.intra.mode = modes[0];
       pred_cu.intra.mode_chroma = modes[0];
       pred_cu.intra.multi_ref_idx = multi_ref_idx;
+      pred_cu.intra.mip_flag = false;
+      pred_cu.intra.mip_is_transposed = false;
+    }
     FILL(pred_cu.cbf, 0);
     search_intra_trdepth(state, x_px, y_px, depth, tr_depth, modes[0], MAX_INT, &pred_cu, lcu, NULL, trafo[0]);
   }
@@ -1170,36 +1191,36 @@ void kvz_search_cu_intra(encoder_state_t * const state,
   double costs[MAX_REF_LINE_IDX][67];
 
   bool enable_mip = state->encoder_control->cfg.mip;
-  int8_t mip_modes[32]; // Modes [0, 15] are non-transposed. Modes [16,31] are transposed.
+  // The maximum number of mip modes is 32. Max modes can be less depending on block size.
+  // Half of the possible modes are transposed, which is indicated by a separate transpose flag
+  int8_t mip_modes[32]; 
   int8_t mip_trafo[32];
   double mip_costs[32];
 
+  // The maximum number of possible MIP modes depend on block size & shape
+  int width = LCU_WIDTH >> depth;
+  int height = width; // TODO: proper height for non-square blocks.
+  int num_mip_modes = 0;
+
   if (enable_mip) {
     for (int i = 0; i < 32; ++i) {
       mip_modes[i] = i;
       mip_costs[i] = MAX_INT;
     }
-  }
-
-  // The maximum number of possible MIP modes depend on block size & shape
-  int width = LCU_WIDTH >> depth;
-  int height = width; // TODO: proper height for non-square blocks.
-  int tmp_modes;
     // MIP_TODO: check for illegal block sizes.
     if (width == 4 && height == 4) {
       // Mip size_id = 0. Num modes = 32
-    tmp_modes = 32;
+      num_mip_modes = 32;
     }
     else if (width == 4 || height == 4 || (width == 8 && height == 8)) {
       // Mip size_id = 0. Num modes = 16
-    tmp_modes = 16;
+      num_mip_modes = 16;
     }
     else {
       // Mip size_id = 0. Num modes = 12
-    tmp_modes = 12;
+      num_mip_modes = 12;
+    }
   }
-  
-  uint8_t num_mip_modes = enable_mip ? tmp_modes : 0;
 
   // Find best intra mode for 2Nx2N.
   kvz_pixel *ref_pixels = &lcu->ref.y[lcu_px.x + lcu_px.y * LCU_WIDTH];