[Analysis] Printing Nets timing Information

vpr/src/analysis/timing_reports.cpp

@@ -1,7 +1,13 @@
 #include "timing_reports.h"
 
+#include <fstream>
+#include <sstream>
+
+#include "timing_reports.h"
+
 #include "tatum/TimingReporter.hpp"
 
+#include "vtr_version.h"
 #include "vpr_types.h"
 #include "globals.h"
 
@@ -61,3 +67,69 @@ void generate_hold_timing_stats(const std::string& prefix,
 
     timing_reporter.report_unconstrained_hold(prefix + "report_unconstrained_timing.hold.rpt", *timing_info.hold_analyzer());
 }
+
+void generate_net_timing_report(const std::string& prefix,
+                                const SetupHoldTimingInfo& timing_info,
+                                const AnalysisDelayCalculator& delay_calc) {
+    /* Create a report file for net timing information */
+    std::ofstream os(prefix + "report_net_timing.rpt");
+    const auto& atom_netlist = g_vpr_ctx.atom().netlist();
+    const auto& atom_lookup = g_vpr_ctx.atom().lookup();
+
+    const auto& timing_ctx = g_vpr_ctx.timing();
+    const auto& timing_graph = timing_ctx.graph;
+
+    os << "# This file is generated by VTR" << std::endl;
+    os << "# Version: " << vtr::VERSION << std::endl;
+    os << "# Revision: " << vtr::VCS_REVISION << std::endl;
+    os << "# For each net, the timing information is reported in the following format:" << std::endl;
+    os << "# netname : Fanout : source_instance <slack_on source pin> : "
+       << "<load pin name1> <slack on load pin name1> <net delay for this net> : "
+       << "<load pin name2> <slack on load pin name2> <net delay for this net> : ..."
+       << std::endl;
+
+    os << std::endl;
+
+    for (const auto& net : atom_netlist.nets()) {
+        /* Skip constant nets */
+        if (atom_netlist.net_is_constant(net)) {
+            continue;
+        }
+
+        const auto& net_name = atom_netlist.net_name(net);
+
+        /* Get source pin and its timing information */
+        const auto& source_pin = *atom_netlist.net_pins(net).begin();
+        auto source_pin_slack = timing_info.setup_pin_slack(source_pin);
+        /* Timing graph node id corresponding to the net's source pin */
+        auto tg_source_node = atom_lookup.atom_pin_tnode(source_pin);
+        VTR_ASSERT(tg_source_node.is_valid());
+
+        const size_t fanout = atom_netlist.net_sinks(net).size();
+        os << net_name << " : " << fanout << " : " << atom_netlist.pin_name(source_pin).c_str() << " " << source_pin_slack << " : ";
+
+        /* Iterate over all fanout pins and print their timing information */
+        for (size_t net_pin_index = 1; net_pin_index <= fanout; ++net_pin_index) {
+            const auto& pin = *(atom_netlist.net_pins(net).begin() + net_pin_index);
+
+            /* Get timing graph node id corresponding to the fanout pin */
+            const auto& tg_sink_node = atom_lookup.atom_pin_tnode(pin);
+            VTR_ASSERT(tg_sink_node.is_valid());
+
+            /* Get timing graph edge id between atom pins */
+            const auto& tg_edge_id = timing_graph->find_edge(tg_source_node, tg_sink_node);
+            VTR_ASSERT(tg_edge_id.is_valid());
+
+            /* Get timing information for the fanout pin */
+            const auto& pin_setup_slack = timing_info.setup_pin_slack(pin);
+            const auto& pin_delay = delay_calc.max_edge_delay(*timing_graph, tg_edge_id);
+
+            const auto& pin_name = atom_netlist.pin_name(pin);
+            os << pin_name << " " << std::scientific << pin_setup_slack << " " << pin_delay;
+            if (net_pin_index < fanout) {
+                os << " : ";
+            }
+        }
+        os << "," << std::endl;
+    }
+}

vpr/src/analysis/timing_reports.h

@@ -21,4 +21,19 @@ void generate_hold_timing_stats(const std::string& prefix,
                                 bool is_flat,
                                 const BlkLocRegistry& blk_loc_registry);
 
+/**
+ * @brief Generates timing information for each net in atom netlist. For each net, the timing information
+ * is reported in the following format:
+ * netname : Fanout : source_instance <slack_on source pin> : 
+ * <load pin name1> <slack on load pin name1> <net delay for this net> : 
+ * <load pin name2> <slack on load pin name2> <net delay for this net> : ...
+ * 
+ * @param prefix The prefix for the report file to be added to filename: report_net_timing.rpt
+ * @param timing_info Updated timing information
+ * @param delay_calc Delay calculator
+ */
+void generate_net_timing_report(const std::string& prefix,
+                                const SetupHoldTimingInfo& timing_info,
+                                const AnalysisDelayCalculator& delay_calc);
+
 #endif

vpr/src/base/SetupVPR.cpp

@@ -716,6 +716,7 @@ static void SetupAnalysisOpts(const t_options& Options, t_analysis_opts& analysi
 
     analysis_opts.timing_update_type = Options.timing_update_type;
     analysis_opts.write_timing_summary = Options.write_timing_summary;
+    analysis_opts.generate_net_timing_report = Options.generate_net_timing_report;
 }
 
 static void SetupPowerOpts(const t_options& Options, t_power_opts* power_opts, t_arch* Arch) {

vpr/src/base/read_options.cpp

@@ -3078,6 +3078,11 @@ argparse::ArgumentParser create_arg_parser(const std::string& prog_name, t_optio
         .help("Writes implemented design final timing summary to the specified JSON, XML or TXT file.")
         .show_in(argparse::ShowIn::HELP_ONLY);
 
+    analysis_grp.add_argument<bool, ParseOnOff>(args.generate_net_timing_report, "--generate_net_timing_report")
+        .help("Generates a net timing report for each net in the design.")
+        .default_value("off")
+        .show_in(argparse::ShowIn::HELP_ONLY);
+
     auto& power_grp = parser.add_argument_group("power analysis options");
 
     power_grp.add_argument<bool, ParseOnOff>(args.do_power, "--power")

vpr/src/base/read_options.h

@@ -271,6 +271,7 @@ struct t_options {
     argparse::ArgValue<e_post_synth_netlist_unconn_handling> post_synth_netlist_unconn_output_handling;
     argparse::ArgValue<bool> post_synth_netlist_module_parameters;
     argparse::ArgValue<std::string> write_timing_summary;
+    argparse::ArgValue<bool> generate_net_timing_report;
 };
 
 argparse::ArgumentParser create_arg_parser(const std::string& prog_name, t_options& args);

vpr/src/base/vpr_api.cpp

@@ -1475,6 +1475,10 @@ void vpr_analysis(const Netlist<>& net_list,
             merged_netlist_writer(atom_ctx.netlist().netlist_name(), analysis_delay_calc, Arch.models, vpr_setup.AnalysisOpts);
         }
 
+        if (vpr_setup.AnalysisOpts.generate_net_timing_report) {
+            generate_net_timing_report(/*prefix=*/"", *timing_info, *analysis_delay_calc);
+        }
+
         //Do power analysis
         // TODO: Still assumes that cluster net list is used
         if (vpr_setup.PowerOpts.do_power) {

vpr/src/base/vpr_types.h

@@ -1351,6 +1351,7 @@ struct t_analysis_opts {
     bool timing_report_skew;
     std::string echo_dot_timing_graph_node;
     std::string write_timing_summary;
+    bool generate_net_timing_report;
 
     e_timing_update_type timing_update_type;
 };