default layer range when the layer is not specified

Author: soheilshahrouz

vpr/src/base/region.cpp

@@ -29,7 +29,7 @@ void RegionRectCoord::set_rect(const vtr::Rect<int>& rect) {
 Region::Region()
     : region_bounds_({std::numeric_limits<int>::max(), std::numeric_limits<int>::max(),
                       std::numeric_limits<int>::min(), std::numeric_limits<int>::min()},
-                      -1, -1)    //these values indicate an empty rectangle
+                      0, 0)    //these values indicate an empty rectangle
     , sub_tile_(NO_SUBTILE) {}
 
 const RegionRectCoord& Region::get_region_bounds() const {

vpr/src/pack/constraints_report.cpp

@@ -44,8 +44,7 @@ bool floorplan_constraints_regions_overfull() {
         const auto [layer_low, layer_high] = region.get_region_bounds().get_layer_range();
         for (const auto & block_type : block_types) {
             int num_assigned_blocks = block_type_counts[block_type.index];
-            int num_tiles = 0;
-            num_tiles = grid_tiles.region_tile_count(region, &block_type);
+            int num_tiles = grid_tiles.region_tile_count(region, &block_type);
             if (num_assigned_blocks > num_tiles) {
                 floorplan_regions_overfull = true;
                 floorplanning_ctx.overfull_regions.push_back(region);