NoC-aware packing optimization and NoC-biased centroid move type

libs/libvtrutil/src/vtr_error.h

@@ -3,6 +3,7 @@
 
 #include <stdexcept>
 #include <string>
+#include <utility>
 
 /**
  * @file
@@ -34,9 +35,9 @@ namespace vtr {
 class VtrError : public std::runtime_error {
   public:
     ///@brief VtrError constructor
-    VtrError(std::string msg = "", std::string new_filename = "", size_t new_linenumber = -1)
+    VtrError(const std::string& msg = "", std::string new_filename = "", size_t new_linenumber = -1)
         : std::runtime_error(msg)
-        , filename_(new_filename)
+        , filename_(std::move(new_filename))
         , linenumber_(new_linenumber) {}
 
     /**

libs/libvtrutil/src/vtr_expr_eval.cpp

@@ -58,13 +58,13 @@ static bool is_char_number(const char ch);
 static bool is_operator(const char ch);
 
 // returns true if the specified name is a known function operator
-static bool is_function(std::string name);
+static bool is_function(const std::string& name);
 
 // returns true if the specified name is a known compound operator
 t_compound_operator is_compound_op(const char* ch);
 
 // returns true if the specified name is a known variable
-static bool is_variable(std::string var);
+static bool is_variable(const std::string& var);
 
 // returns the length of any identifier (e.g. name, function) starting at the beginning of str
 static int identifier_length(const char* str);
@@ -76,14 +76,14 @@ static bool goto_next_char(int* str_ind, const string& pw_formula, char ch);
 bool same_string(std::string str1, std::string str2);
 
 //checks if the block indicated by the user was one of the moved blocks in the last perturbation
-int in_blocks_affected(std::string expression_left);
+int in_blocks_affected(const std::string& expression_left);
 
 //the function of += operator
 bool additional_assignment_op(int arg1, int arg2);
 
 /**** Function Implementations ****/
 /* returns integer result according to specified non-piece-wise formula and data */
-int FormulaParser::parse_formula(std::string formula, const t_formula_data& mydata, bool is_breakpoint) {
+int FormulaParser::parse_formula(const std::string& formula, const t_formula_data& mydata, bool is_breakpoint) {
     int result = -1;
 
     /* output in reverse-polish notation */
@@ -150,7 +150,7 @@ int FormulaParser::parse_piecewise_formula(const char* formula, const t_formula_
         }
         tmp_ind_count = str_ind - tmp_ind_start; /* range start is between { and : */
         substr = pw_formula.substr(tmp_ind_start, tmp_ind_count);
-        range_start = parse_formula(substr.c_str(), mydata);
+        range_start = parse_formula(substr, mydata);
 
         /* get the end of the range */
         tmp_ind_start = str_ind + 1;
@@ -160,7 +160,7 @@ int FormulaParser::parse_piecewise_formula(const char* formula, const t_formula_
         }
         tmp_ind_count = str_ind - tmp_ind_start; /* range end is between : and } */
         substr = pw_formula.substr(tmp_ind_start, tmp_ind_count);
-        range_end = parse_formula(substr.c_str(), mydata);
+        range_end = parse_formula(substr, mydata);
 
         if (range_start > range_end) {
             throw vtr::VtrError(vtr::string_fmt("parse_piecewise_formula: range_start, %d, is bigger than range end, %d\n", range_start, range_end), __FILE__, __LINE__);
@@ -287,8 +287,6 @@ static void formula_to_rpn(const char* formula, const t_formula_data& mydata, ve
         rpn_output.push_back(fobj_dummy);
         op_stack.pop();
     }
-
-    return;
 }
 
 /* Fills the formula object fobj according to specified character and mydata,
@@ -352,7 +350,7 @@ static void get_formula_object(const char* ch, int& ichar, const t_formula_data&
         }
         ichar--;
         fobj->type = E_FML_NUMBER;
-        fobj->data.num = vtr::atoi(ss.str().c_str());
+        fobj->data.num = vtr::atoi(ss.str());
     } else if (is_compound_op(ch) != E_COM_OP_UNDEFINED) {
         fobj->type = E_FML_OPERATOR;
         t_compound_operator comp_op_code = is_compound_op(ch);
@@ -415,8 +413,6 @@ static void get_formula_object(const char* ch, int& ichar, const t_formula_data&
                 break;
         }
     }
-
-    return;
 }
 
 /* returns integer specifying precedence of passed-in operator. higher integer
@@ -562,7 +558,6 @@ static void handle_bracket(const Formula_Object& fobj, vector<Formula_Object>& r
             }
         } while (keep_going);
     }
-    return;
 }
 
 /* used by the shunting-yard formula parser to deal with commas, ie ','. These occur in function calls*/
@@ -770,7 +765,7 @@ static bool is_operator(const char ch) {
 }
 
 //returns true if string signifies a function e.g max, min
-static bool is_function(std::string name) {
+static bool is_function(const std::string& name) {
     if (name == "min"
         || name == "max"
         || name == "gcd"
@@ -801,7 +796,7 @@ t_compound_operator is_compound_op(const char* ch) {
 }
 
 //checks if the entered string is a known variable name
-static bool is_variable(std::string var_name) {
+static bool is_variable(const std::string& var_name) {
     if (same_string(var_name, "from_block") || same_string(var_name, "temp_count") || same_string(var_name, "move_num") || same_string(var_name, "route_net_id") || same_string(var_name, "in_blocks_affected") || same_string(var_name, "router_iter")) {
         return true;
     }
@@ -849,11 +844,11 @@ bool same_string(std::string str1, std::string str2) {
     str1.erase(remove(str1.begin(), str1.end(), ' '), str1.end());
     str2.erase(remove(str2.begin(), str2.end(), ' '), str2.end());
 
-    //converting both strings to lower case to eliminate case sensivity
+    //converting both strings to lower case to eliminate case sensitivity
     std::transform(str1.begin(), str1.end(), str1.begin(), ::tolower);
     std::transform(str2.begin(), str2.end(), str2.begin(), ::tolower);
 
-    return (str1.compare(str2) == 0);
+    return (str1 == str2);
 }
 
 //the += operator
@@ -870,7 +865,7 @@ bool additional_assignment_op(int arg1, int arg2) {
 //recognizes the block_id to look for (entered by the user)
 //then looks for that block_id in all the blocks moved in the last perturbation.
 //returns the block id if found, else just -1
-int in_blocks_affected(std::string expression_left) {
+int in_blocks_affected(const std::string& expression_left) {
     int wanted_block = -1;
     int found_block;
     std::stringstream ss;

libs/libvtrutil/src/vtr_expr_eval.h

@@ -214,7 +214,7 @@ class FormulaParser {
     FormulaParser& operator=(const FormulaParser&) = delete;
 
     ///@brief returns integer result according to specified formula and data
-    int parse_formula(std::string formula, const t_formula_data& mydata, bool is_breakpoint = false);
+    int parse_formula(const std::string& formula, const t_formula_data& mydata, bool is_breakpoint = false);
 
     ///@brief returns integer result according to specified piece-wise formula and data
     int parse_piecewise_formula(const char* formula, const t_formula_data& mydata);

vpr/src/base/CheckSetup.cpp

@@ -12,7 +12,7 @@ void CheckSetup(const t_packer_opts& PackerOpts,
                 const t_router_opts& RouterOpts,
                 const t_det_routing_arch& RoutingArch,
                 const std::vector<t_segment_inf>& Segments,
-                const t_timing_inf Timing,
+                const t_timing_inf& Timing,
                 const t_chan_width_dist Chans) {
     int i;
     int Tmp;
@@ -31,7 +31,7 @@ void CheckSetup(const t_packer_opts& PackerOpts,
             "This is allowed, but strange, and circuit speed will suffer.\n");
     }
 
-    if ((false == Timing.timing_analysis_enabled)
+    if (!Timing.timing_analysis_enabled
         && (PlacerOpts.place_algorithm.is_timing_driven())) {
         /* May work, not tested */
         VPR_FATAL_ERROR(VPR_ERROR_OTHER,
@@ -72,7 +72,7 @@ void CheckSetup(const t_packer_opts& PackerOpts,
     for (i = 0; i < (int)Segments.size(); ++i) {
         Tmp = Segments[i].arch_opin_switch;
         auto& device_ctx = g_vpr_ctx.device();
-        if (false == device_ctx.arch_switch_inf[Tmp].buffered()) {
+        if (!device_ctx.arch_switch_inf[Tmp].buffered()) {
             VPR_FATAL_ERROR(VPR_ERROR_OTHER,
                             "arch_opin_switch (#%d) of segment type #%d is not buffered.\n", Tmp, i);
         }

vpr/src/base/CheckSetup.h

@@ -7,7 +7,7 @@ void CheckSetup(const t_packer_opts& PackerOpts,
                 const t_router_opts& RouterOpts,
                 const t_det_routing_arch& RoutingArch,
                 const std::vector<t_segment_inf>& Segments,
-                const t_timing_inf Timing,
+                const t_timing_inf& Timing,
                 const t_chan_width_dist Chans);
 
 #endif

vpr/src/base/SetupGrid.cpp

@@ -46,7 +46,7 @@ static void set_grid_block_type(int priority,
                                 const t_metadata_dict* meta);
 
 ///@brief Create the device grid based on resource requirements
-DeviceGrid create_device_grid(std::string layout_name, const std::vector<t_grid_def>& grid_layouts, const std::map<t_logical_block_type_ptr, size_t>& minimum_instance_counts, float target_device_utilization) {
+DeviceGrid create_device_grid(const std::string& layout_name, const std::vector<t_grid_def>& grid_layouts, const std::map<t_logical_block_type_ptr, size_t>& minimum_instance_counts, float target_device_utilization) {
     if (layout_name == "auto") {
         //Auto-size the device
         //
@@ -78,9 +78,9 @@ DeviceGrid create_device_grid(std::string layout_name, const std::vector<t_grid_
 }
 
 ///@brief Create the device grid based on dimensions
-DeviceGrid create_device_grid(std::string layout_name, const std::vector<t_grid_def>& grid_layouts, size_t width, size_t height) {
+DeviceGrid create_device_grid(const std::string& layout_name, const std::vector<t_grid_def>& grid_layouts, size_t width, size_t height) {
     if (layout_name == "auto") {
-        VTR_ASSERT(grid_layouts.size() > 0);
+        VTR_ASSERT(!grid_layouts.empty());
         //Auto-size
         if (grid_layouts[0].grid_type == GridDefType::AUTO) {
             //Auto layout of the specified dimensions
@@ -145,7 +145,7 @@ DeviceGrid create_device_grid(std::string layout_name, const std::vector<t_grid_
  * If an auto grid layouts are specified, the smallest dynamicly sized grid is picked
  */
 static DeviceGrid auto_size_device_grid(const std::vector<t_grid_def>& grid_layouts, const std::map<t_logical_block_type_ptr, size_t>& minimum_instance_counts, float maximum_device_utilization) {
-    VTR_ASSERT(grid_layouts.size() > 0);
+    VTR_ASSERT(!grid_layouts.empty());
 
     DeviceGrid grid;
 
@@ -281,6 +281,7 @@ static std::vector<t_logical_block_type_ptr> grid_overused_resources(const Devic
 
     //Sort so we allocate logical blocks with the fewest equivalent sites first (least flexible)
     std::vector<const t_logical_block_type*> logical_block_types;
+    logical_block_types.reserve(device_ctx.logical_block_types.size());
     for (auto& block_type : device_ctx.logical_block_types) {
         logical_block_types.push_back(&block_type);
     }

vpr/src/base/SetupGrid.h

@@ -13,13 +13,16 @@
 #include "physical_types.h"
 
 ///@brief Find the device satisfying the specified minimum resources
-DeviceGrid create_device_grid(std::string layout_name,
+DeviceGrid create_device_grid(const std::string& layout_name,
                               const std::vector<t_grid_def>& grid_layouts,
                               const std::map<t_logical_block_type_ptr, size_t>& minimum_instance_counts,
                               float target_device_utilization);
 
 ///@brief Find the device close in size to the specified dimensions
-DeviceGrid create_device_grid(std::string layout_name, const std::vector<t_grid_def>& grid_layouts, size_t min_width, size_t min_height);
+DeviceGrid create_device_grid(const std::string& layout_name,
+                              const std::vector<t_grid_def>& grid_layouts,
+                              size_t min_width,
+                              size_t min_height);
 
 /**
  * @brief Calculate the device utilization

vpr/src/base/SetupVPR.cpp

@@ -399,7 +399,7 @@ static void SetupRoutingArch(const t_arch& Arch,
     RoutingArch->R_minW_pmos = Arch.R_minW_pmos;
     RoutingArch->Fs = Arch.Fs;
     RoutingArch->directionality = BI_DIRECTIONAL;
-    if (Arch.Segments.size()) {
+    if (!Arch.Segments.empty()) {
         RoutingArch->directionality = Arch.Segments[0].directionality;
     }
 
@@ -740,6 +740,7 @@ static void SetupNocOpts(const t_options& Options, t_noc_opts* NocOpts) {
     NocOpts->noc_latency_weighting = Options.noc_latency_weighting;
     NocOpts->noc_congestion_weighting = Options.noc_congestion_weighting;
     NocOpts->noc_swap_percentage = Options.noc_swap_percentage;
+    NocOpts->noc_centroid_weight = Options.noc_centroid_weight;
     NocOpts->noc_placement_file_name = Options.noc_placement_file_name;
 }
 

vpr/src/base/atom_netlist.cpp

@@ -115,7 +115,7 @@ AtomBlockId AtomNetlist::find_atom_pin_driver(const AtomBlockId blk_id, const t_
     return AtomBlockId::INVALID();
 }
 
-std::unordered_set<std::string> AtomNetlist::net_aliases(const std::string net_name) const {
+std::unordered_set<std::string> AtomNetlist::net_aliases(const std::string& net_name) const {
     auto net_id = find_net(net_name);
     VTR_ASSERT(net_id != AtomNetId::INVALID());
 
@@ -137,7 +137,7 @@ std::unordered_set<std::string> AtomNetlist::net_aliases(const std::string net_n
  * Mutators
  *
  */
-AtomBlockId AtomNetlist::create_block(const std::string name, const t_model* model, const TruthTable truth_table) {
+AtomBlockId AtomNetlist::create_block(const std::string& name, const t_model* model, const TruthTable& truth_table) {
     AtomBlockId blk_id = Netlist::create_block(name);
 
     //Initialize the data
@@ -205,7 +205,7 @@ AtomPinId AtomNetlist::create_pin(const AtomPortId port_id, BitIndex port_bit, c
     return pin_id;
 }
 
-AtomNetId AtomNetlist::create_net(const std::string name) {
+AtomNetId AtomNetlist::create_net(const std::string& name) {
     AtomNetId net_id = Netlist::create_net(name);
 
     //Check post-conditions: size
@@ -214,11 +214,11 @@ AtomNetId AtomNetlist::create_net(const std::string name) {
     return net_id;
 }
 
-AtomNetId AtomNetlist::add_net(const std::string name, AtomPinId driver, std::vector<AtomPinId> sinks) {
+AtomNetId AtomNetlist::add_net(const std::string& name, AtomPinId driver, std::vector<AtomPinId> sinks) {
     return Netlist::add_net(name, driver, sinks);
 }
 
-void AtomNetlist::add_net_alias(const std::string net_name, const std::string alias_net_name) {
+void AtomNetlist::add_net_alias(const std::string& net_name, const std::string& alias_net_name) {
     auto net_id = find_net(net_name);
     VTR_ASSERT(net_id != AtomNetId::INVALID());
 

vpr/src/base/atom_netlist.h

@@ -157,7 +157,7 @@ class AtomNetlist : public Netlist<AtomBlockId, AtomPortId, AtomPinId, AtomNetId
      *
      *   @param net_name   name of the net from which the aliases are extracted
      */
-    std::unordered_set<std::string> net_aliases(const std::string net_name) const;
+    std::unordered_set<std::string> net_aliases(const std::string& net_name) const;
 
   public: //Public Mutators
     /*
@@ -173,7 +173,7 @@ class AtomNetlist : public Netlist<AtomBlockId, AtomPortId, AtomPinId, AtomNetId
      *                        The truth_table is optional and only relevant for LUTs (where it describes the logic function)
      *                        and Flip-Flops/latches (where it consists of a single entry defining the initial state).
      */
-    AtomBlockId create_block(const std::string name, const t_model* model, const TruthTable truth_table = TruthTable());
+    AtomBlockId create_block(const std::string& name, const t_model* model, const TruthTable& truth_table = TruthTable());
 
     /**
      * @brief Create or return an existing port in the netlist
@@ -199,7 +199,7 @@ class AtomNetlist : public Netlist<AtomBlockId, AtomPortId, AtomPinId, AtomNetId
      *
      *   @param name   The unique name of the net
      */
-    AtomNetId create_net(const std::string name); //An empty or existing net
+    AtomNetId create_net(const std::string& name); //An empty or existing net
 
     /**
      * @brief Create a completely specified net from specified driver and sinks
@@ -208,7 +208,7 @@ class AtomNetlist : public Netlist<AtomBlockId, AtomPortId, AtomPinId, AtomNetId
      *   @param driver     The net's driver pin
      *   @param sinks      The net's sink pins
      */
-    AtomNetId add_net(const std::string name, AtomPinId driver, std::vector<AtomPinId> sinks);
+    AtomNetId add_net(const std::string& name, AtomPinId driver, std::vector<AtomPinId> sinks);
 
     /**
      * @brief Adds a value to the net aliases set for a given net name in the net_aliases_map.
@@ -218,7 +218,7 @@ class AtomNetlist : public Netlist<AtomBlockId, AtomPortId, AtomPinId, AtomNetId
      *   @param net_name        The net to be added to the map
      *   @param alias_net_name  The alias of the assigned clock net id
      */
-    void add_net_alias(const std::string net_name, std::string alias_net_name);
+    void add_net_alias(const std::string& net_name, const std::string& alias_net_name);
 
   private: //Private members
     /*

vpr/src/base/constraints_load.cpp

@@ -1,6 +1,6 @@
 #include "constraints_load.h"
 
-void echo_constraints(char* filename, VprConstraints constraints) {
+void echo_constraints(char* filename, const VprConstraints& constraints) {
     FILE* fp;
     fp = vtr::fopen(filename, "w");
 

vpr/src/base/constraints_load.h

@@ -8,6 +8,6 @@
 #include "vtr_vector.h"
 
 ///@brief Used to print vpr's floorplanning constraints to an echo file "vpr_constraints.echo"
-void echo_constraints(char* filename, VprConstraints constraints);
+void echo_constraints(char* filename, const VprConstraints& constraints);
 
 #endif