add comments

Author: soheilshahrouz

vpr/src/base/vpr_api.cpp

@@ -462,7 +462,9 @@ void vpr_create_device_grid(const t_vpr_setup& vpr_setup, const t_arch& Arch) {
     float target_device_utilization = vpr_setup.PackerOpts.target_device_utilization;
     device_ctx.grid = create_device_grid(vpr_setup.device_layout, Arch.grid_layouts, num_type_instances, target_device_utilization);
 
-    VTR_ASSERT_MSG(device_ctx.grid.get_num_layers() <= MAX_NUM_LAYERS, "Number of layers should be less than MAX_NUM_LAYERS. If you need more layers, please increase the value of MAX_NUM_LAYERS in vpr_types.h");
+    VTR_ASSERT_MSG(device_ctx.grid.get_num_layers() <= MAX_NUM_LAYERS,
+                   "Number of layers should be less than MAX_NUM_LAYERS. "
+                   "If you need more layers, please increase the value of MAX_NUM_LAYERS in vpr_types.h");
 
     /*
      *Report on the device
@@ -1455,7 +1457,7 @@ void vpr_analysis(const Netlist<>& net_list,
         generate_setup_timing_stats(/*prefix=*/"", *timing_info,
                                     *analysis_delay_calc, vpr_setup.AnalysisOpts, vpr_setup.RouterOpts.flat_routing);
 
-        //Write the post-syntesis netlist
+        //Write the post-synthesis netlist
         if (vpr_setup.AnalysisOpts.gen_post_synthesis_netlist) {
             netlist_writer(atom_ctx.nlist.netlist_name().c_str(), analysis_delay_calc,
                            vpr_setup.AnalysisOpts);

vpr/src/route/router_lookahead_map_utils.cpp

@@ -18,6 +18,13 @@
 #include "route_common.h"
 #include "route_debug.h"
 
+/**
+ * We will profile delay/congestion using this many tracks for each wire type.
+ * Larger values increase the time to compute the lookahead, but may give
+ * more accurate lookahead estimates during routing.
+ */
+static constexpr int MAX_TRACK_OFFSET = 16;
+
 static void dijkstra_flood_to_wires(int itile, RRNodeId inode, util::t_src_opin_delays& src_opin_delays);
 
 static void dijkstra_flood_to_ipins(RRNodeId node, util::t_chan_ipins_delays& chan_ipins_delays);
@@ -51,13 +58,42 @@ static void expand_dijkstra_neighbours(util::PQ_Entry parent_entry,
                                        vtr::vector<RRNodeId, bool>& node_expanded,
                                        std::priority_queue<util::PQ_Entry>& pq);
 
-static std::pair<int, int> adjust_rr_position(const RRNodeId rr);
 
-static std::pair<int, int> adjust_rr_pin_position(const RRNodeId rr);
+/**
+ * @brief Computes the adjusted position of an RR graph node.
+ * This function does not modify the position of the given node.
+ * It only returns the computed adjusted position.
+ * @param rr The ID of the node whose adjusted position is desired.
+ * @return The adjusted position (x, y).
+ */
+static std::pair<int, int> get_adjusted_rr_position(RRNodeId rr);
+
+/**
+ * @brief Computes the adjusted location of a pin to match the position of
+ * the channel it can reach based on which side of the block it is at.
+ * @param rr The corresponding node of a pin whose adjusted positions
+ * is desired.
+ * @return The adjusted position (x, y).
+ */
+static std::pair<int, int> get_adjusted_rr_pin_position(RRNodeId rr);
 
-static std::pair<int, int> adjust_rr_wire_position(const RRNodeId rr);
+/**
+ * @brief Computed the adjusted position of a node of type
+ * CHANX or CHANY. For uni-directional wires, return the position
+ * of the driver, and for bi-directional wires, compute the middle point.
+ * @param rr The ID of the node whose adjusted position is desired.
+ * @return The adjusted position (x, y).
+ */
+static std::pair<int, int> get_adjusted_rr_wire_position(RRNodeId rr);
 
-static std::pair<int, int> adjust_rr_src_sink_position(const RRNodeId rr);
+/**
+ * @brief Computes the adjusted position and source and sink nodes.
+ * SOURCE/SINK nodes assume the full dimensions of their associated block/
+ * This function computes the average position for the given node.
+ * @param rr SOURCE or SINK node whose adjusted position is needed.
+ * @return The adjusted position (x, y).
+ */
+static std::pair<int, int> get_adjusted_rr_src_sink_position(RRNodeId rr);
 
 // Constants needed to reduce the bounding box when expanding CHAN wires to reach the IPINs.
 // These are used when finding all the delays to get to the IPINs of all the different tile types
@@ -549,7 +585,6 @@ RRNodeId get_start_node(int layer, int start_x, int start_y, int target_x, int t
     return result;
 }
 
-/* returns the absolute delta_x and delta_y offset required to reach to_node from from_node */
 std::pair<int, int> get_xy_deltas(RRNodeId from_node, RRNodeId to_node) {
     auto& device_ctx = g_vpr_ctx.device();
     const auto& rr_graph = device_ctx.rr_graph;
@@ -561,8 +596,8 @@ std::pair<int, int> get_xy_deltas(RRNodeId from_node, RRNodeId to_node) {
 
     if (!is_chan(from_type) && !is_chan(to_type)) {
         //Alternate formulation for non-channel types
-        auto [from_x, from_y] = adjust_rr_position(from_node);
-        auto [to_x, to_y] = adjust_rr_position(to_node);
+        auto [from_x, from_y] = get_adjusted_rr_position(from_node);
+        auto [to_x, to_y] = get_adjusted_rr_position(to_node);
 
         delta_x = to_x - from_x;
         delta_y = to_y - from_y;
@@ -757,7 +792,7 @@ t_routing_cost_map get_routing_cost_map(int longest_seg_length,
         routing_cost_map.fill(Expansion_Cost_Entry());
 
         // to avoid multiple memory allocation and de-allocations in run_dijkstra()
-        // dijkstra_data is created outside the for loop as passed by reference to dijkstra_data()
+        // dijkstra_data is created outside the for loop and passed by reference to dijkstra_data()
         t_dijkstra_data dijkstra_data;
 
         for (RRNodeId sample_node : sample_nodes) {
@@ -1375,23 +1410,23 @@ static void expand_dijkstra_neighbours(util::PQ_Entry parent_entry,
     }
 }
 
-static std::pair<int, int> adjust_rr_position(const RRNodeId rr) {
+static std::pair<int, int> get_adjusted_rr_position(const RRNodeId rr) {
     auto& device_ctx = g_vpr_ctx.device();
     const auto& rr_graph = device_ctx.rr_graph;
 
     e_rr_type rr_type = rr_graph.node_type(rr);
 
     if (is_chan(rr_type)) {
-        return adjust_rr_wire_position(rr);
+        return get_adjusted_rr_wire_position(rr);
     } else if (is_pin(rr_type)) {
-        return adjust_rr_pin_position(rr);
+        return get_adjusted_rr_pin_position(rr);
     } else {
         VTR_ASSERT_SAFE(is_src_sink(rr_type));
-        return adjust_rr_src_sink_position(rr);
+        return get_adjusted_rr_src_sink_position(rr);
     }
 }
 
-static std::pair<int, int> adjust_rr_pin_position(const RRNodeId rr) {
+static std::pair<int, int> get_adjusted_rr_pin_position(const RRNodeId rr) {
     /*
      * VPR uses a co-ordinate system where wires above and to the right of a block
      * are at the same location as the block:
@@ -1458,7 +1493,7 @@ static std::pair<int, int> adjust_rr_pin_position(const RRNodeId rr) {
     return {x, y};
 }
 
-static std::pair<int, int> adjust_rr_wire_position(const RRNodeId rr) {
+static std::pair<int, int> get_adjusted_rr_wire_position(const RRNodeId rr) {
     auto& device_ctx = g_vpr_ctx.device();
     const auto& rr_graph = device_ctx.rr_graph;
 
@@ -1481,7 +1516,7 @@ static std::pair<int, int> adjust_rr_wire_position(const RRNodeId rr) {
     }
 }
 
-static std::pair<int, int> adjust_rr_src_sink_position(const RRNodeId rr) {
+static std::pair<int, int> get_adjusted_rr_src_sink_position(const RRNodeId rr) {
     //SOURCE/SINK nodes assume the full dimensions of their
     //associated block
 

vpr/src/route/router_lookahead_map_utils.h

@@ -25,9 +25,6 @@
 #include "rr_node.h"
 #include "rr_graph_view.h"
 
-/* we will profile delay/congestion using this many tracks for each wire type */
-static constexpr int MAX_TRACK_OFFSET = 16;
-
 namespace util {
 
 class Cost_Entry;
@@ -330,6 +327,14 @@ t_ipin_primitive_sink_delays compute_intra_tile_dijkstra(const RRGraphView& rr_g
 /* returns index of a node from which to start routing */
 RRNodeId get_start_node(int layer, int start_x, int start_y, int target_x, int target_y, t_rr_type rr_type, int seg_index, int track_offset);
 
+/**
+ * @brief Computes the absolute delta_x and delta_y offset
+ * required to reach to_node from from_node
+ * @param from_node The starting node
+ * @param to_node The destination node
+ * @return (delta_x, delta_y) offset required to reach to
+ * to_node from from_node.
+ */
 std::pair<int, int> get_xy_deltas(RRNodeId from_node, RRNodeId to_node);
 
 t_routing_cost_map get_routing_cost_map(int longest_seg_length,

vpr/src/route/rr_graph.cpp

@@ -336,14 +336,14 @@ static void add_intra_tile_edges_rr_graph(RRGraphBuilder& rr_graph_builder,
  * @brief Add the intra-cluster edges
  * @param rr_graph_builder
  * @param num_collapsed_nodes Return the number of nodes that are removed due to collapsing
- * @param cluster_blk_id Cluser block id of the cluster that its edges are being added
+ * @param cluster_blk_id Cluster block id of the cluster that its edges are being added
  * @param i
  * @param j
  * @param cap Capacity number of the location that cluster is being mapped to
  * @param R_minW_nmos
  * @param R_minW_pmos
  * @param rr_edges_to_create
- * @param nodes_to_collapse Sotre the nodes in the cluster that needs to be collapsed
+ * @param nodes_to_collapse Store the nodes in the cluster that needs to be collapsed
  * @param grid
  * @param is_flat
  * @param load_rr_graph
@@ -407,7 +407,7 @@ static int add_edges_for_collapsed_nodes(RRGraphBuilder& rr_graph_builder,
                                          int j,
                                          bool load_rr_graph);
 /**
- * @note This funtion is used to add the fan-in edges of the given chain node to the chain's sink with the modified delay
+ * @note This function is used to add the fan-in edges of the given chain node to the chain's sink with the modified delay
  * @param rr_graph_builder
  * @param rr_edges_to_create
  * @param num_collapsed_pins
@@ -773,7 +773,7 @@ void create_rr_graph(const t_graph_type graph_type,
 
     // Write out rr graph file if needed - Currently, writing the flat rr-graph is not supported since loading from a flat rr-graph is not supported.
     // When this function is called in any stage other than routing, the is_flat flag passed to this function is false, regardless of the flag passed
-    // through command line. So, the graph conrresponding to global resources will be created and written down to file if needed. During routing, if flat-routing
+    // through command line. So, the graph corresponding to global resources will be created and written down to file if needed. During routing, if flat-routing
     // is enabled, intra-cluster resources will be added to the graph, but this new bigger graph will not be written down.
     if (!det_routing_arch->write_rr_graph_filename.empty() && !is_flat) {
         write_rr_graph(&mutable_device_ctx.rr_graph_builder,
@@ -4465,7 +4465,7 @@ static std::vector<bool> alloc_and_load_perturb_opins(const t_physical_tile_type
         }
 
         n = step_size / prime_factors[i];
-        n = n - (float)vtr::nint(n); /* fractinal part */
+        n = n - (float)vtr::nint(n); /* fractional part */
         if (fabs(n) < threshold) {
             perturb_opins[0] = true;
             break;
@@ -4512,7 +4512,7 @@ static RRNodeId pick_best_direct_connect_target_rr_node(const RRGraphView& rr_gr
                 }
 
                 //Include a partial unit of distance based on side alignment to ensure
-                //we preferr facing sides
+                //we prefer facing sides
                 if ((from_side == RIGHT && to_side == LEFT)
                     || (from_side == LEFT && to_side == RIGHT)
                     || (from_side == TOP && to_side == BOTTOM)