add compute_non_3d_sg_link_geometry() function

Author: soheilshahrouz

vpr/src/route/rr_graph_generation/build_scatter_gathers.cpp

@@ -393,3 +393,40 @@ void convert_interposer_cuts_to_sg_patterns(const std::vector<t_layer_def>& inte
         }
     }
 }
+
+void compute_non_3d_sg_link_geometry(const t_physical_tile_loc& src_loc,
+                                     const t_physical_tile_loc& dst_loc,
+                                     e_rr_type& chan_type,
+                                     int& xlow, int& xhigh,
+                                     int& ylow, int& yhigh,
+                                     Direction& direction) {
+    VTR_ASSERT_SAFE(src_loc.layer_num == dst_loc.layer_num);
+
+    if (dst_loc.x > src_loc.x) {
+        chan_type = e_rr_type::CHANX;
+        ylow = yhigh = dst_loc.y;
+        xlow = src_loc.x + 1;
+        xhigh = dst_loc.x;
+        direction = Direction::INC;
+    } else if (dst_loc.x < src_loc.x) {
+        chan_type = e_rr_type::CHANX;
+        ylow = yhigh = dst_loc.y;
+        xlow = dst_loc.x + 1;
+        xhigh = src_loc.x;
+        direction = Direction::DEC;
+    } else if (dst_loc.y > src_loc.y) {
+        chan_type = e_rr_type::CHANY;
+        xlow = xhigh = dst_loc.x;
+        ylow = src_loc.y + 1;
+        yhigh = dst_loc.y;
+        direction = Direction::INC;
+    } else if (dst_loc.y < src_loc.y) {
+        chan_type = e_rr_type::CHANY;
+        xlow = xhigh = dst_loc.x;
+        ylow = dst_loc.y + 1;
+        yhigh = src_loc.y;
+        direction = Direction::DEC;
+    } else {
+        VTR_ASSERT_MSG(false, "Source and destination locations cannot be identical");
+    }
+}

vpr/src/route/rr_graph_generation/build_scatter_gathers.h

@@ -74,3 +74,14 @@ std::vector<t_bottleneck_link> alloc_and_load_scatter_gather_connections(const s
  */
 void convert_interposer_cuts_to_sg_patterns(const std::vector<t_layer_def>& interposer_inf,
                                             std::vector<t_scatter_gather_pattern>& sg_patterns);
+
+/**
+* @brief Computes the channel type, direction, and coordinate span between two locations
+*        on the same layer. Used by SG link construction routines to determine geometry.
+*/
+void compute_non_3d_sg_link_geometry(const t_physical_tile_loc& src_loc,
+                                     const t_physical_tile_loc& dst_loc,
+                                     e_rr_type& chan_type,
+                                     int& xlow, int& xhigh,
+                                     int& ylow, int& yhigh,
+                                     Direction& direction);

vpr/src/route/rr_graph_generation/rr_graph.cpp

@@ -2074,37 +2074,15 @@ static void add_and_connect_non_3d_sg_links(RRGraphBuilder& rr_graph_builder,
 
         int xlow, xhigh, ylow, yhigh;
         Direction direction;
+        e_rr_type chan_type;
         const t_physical_tile_loc& src_loc = link.gather_loc;
         const t_physical_tile_loc& dst_loc = link.scatter_loc;
 
         // Step 1: Determine the link’s direction and its spatial span.
         // SG links are confined to one layer (non-3D), but can run in X or Y.
         VTR_ASSERT_SAFE(src_loc.layer_num == dst_loc.layer_num);
         const int layer = src_loc.layer_num;
-
-        if (dst_loc.x > src_loc.x) {
-            direction = Direction::INC;
-            ylow = yhigh = dst_loc.y;
-            xlow = src_loc.x + 1;
-            xhigh = dst_loc.x;
-        } else if (dst_loc.x < src_loc.x) {
-            direction = Direction::DEC;
-            ylow = yhigh = dst_loc.y;
-            xlow = dst_loc.x + 1;
-            xhigh = src_loc.x;
-        } else if (dst_loc.y > src_loc.y) {
-            direction = Direction::INC;
-            xlow = xhigh = dst_loc.x;
-            ylow = src_loc.y + 1;
-            yhigh = dst_loc.y;
-        } else if (dst_loc.y < src_loc.y) {
-            direction = Direction::DEC;
-            xlow = xhigh = dst_loc.x;
-            ylow = dst_loc.y + 1;
-            yhigh = src_loc.y;
-        } else {
-            VTR_ASSERT(false);
-        }
+        compute_non_3d_sg_link_geometry(src_loc, dst_loc, chan_type, xlow, xhigh, ylow, yhigh,direction);
 
         // Retrieve the node ID and track number allocated earlier
         const RRNodeId node_id = sg_node_indices[i].first;

vpr/src/route/rr_graph_generation/rr_node_indices.cpp

@@ -380,36 +380,13 @@ std::vector<std::pair<RRNodeId, int>> alloc_and_load_non_3d_sg_pattern_rr_node_i
     for (const t_bottleneck_link& link : bottleneck_links) {
         int xlow, xhigh, ylow, yhigh;
         e_rr_type chan_type;
+        Direction direction;
         const t_physical_tile_loc& src_loc = link.gather_loc;
         const t_physical_tile_loc& dst_loc = link.scatter_loc;
 
-        VTR_ASSERT_SAFE(src_loc.layer_num == dst_loc.layer_num);
-        const int layer = src_loc.layer_num;
-
         // Step 1: Determine the channel type (CHANX/CHANY) and span coordinates
-        if (dst_loc.x > src_loc.x) {
-            chan_type = e_rr_type::CHANX;
-            ylow = yhigh = dst_loc.y;
-            xlow = src_loc.x + 1;
-            xhigh = dst_loc.x;
-        } else if (dst_loc.x < src_loc.x) {
-            chan_type = e_rr_type::CHANX;
-            ylow = yhigh = dst_loc.y;
-            xlow = dst_loc.x + 1;
-            xhigh = src_loc.x;
-        } else if (dst_loc.y > src_loc.y) {
-            chan_type = e_rr_type::CHANY;
-            xlow = xhigh = dst_loc.x;
-            ylow = src_loc.y + 1;
-            yhigh = dst_loc.y;
-        } else if (dst_loc.y < src_loc.y) {
-            chan_type = e_rr_type::CHANY;
-            xlow = xhigh = dst_loc.x;
-            ylow = dst_loc.y + 1;
-            yhigh = src_loc.y;
-        } else {
-            VTR_ASSERT(false);
-        }
+        const int layer = src_loc.layer_num;
+        compute_non_3d_sg_link_geometry(src_loc, dst_loc, chan_type, xlow, xhigh, ylow, yhigh,direction);
 
         // Select the appropriate ptc matrix for this channel type
         vtr::NdMatrix<int, 3>& ptc_matrix = (chan_type == e_rr_type::CHANX) ? chanx_ptc : chany_ptc;