From 23103781431dac4859b0631c86b8eec3784cf908 Mon Sep 17 00:00:00 2001
From: Kanellopoulos Konstantinos <konkanello@gmail.com>
Date: Wed, 10 Dec 2025 16:34:27 +0100
Subject: [PATCH] Fix warmup phase statistics and multicore CPU handling

- Fix ROI stats reporting: use roi_instr/roi_cycle for simulation phases
  and sim_instr/sim_cycle for warmup phases
- Fix end_phase() to only update roi_stats during simulation (not warmup)
- Only call end_phase for the CPU that actually finished
- Add trace file extensions to .gitignore (*.xz, *.gz, *.trace)
- Update default config to 2 cores for testing multicore scenarios
---
 .gitignore           |  5 +++++
 champsim_config.json |  2 +-
 src/champsim.cc      | 32 +++++++++++++++++++++++++-------
 src/ooo_cpu.cc       | 12 ++++++++----
 4 files changed, 39 insertions(+), 12 deletions(-)

diff --git a/.gitignore b/.gitignore
index 63df0656db..3c57b7b9c8 100644
--- a/.gitignore
+++ b/.gitignore
@@ -30,3 +30,8 @@ compile_commands.json
 
 .vscode/
 **/.DS_Store
+
+# Large trace files
+*.xz
+*.gz
+*.trace
diff --git a/champsim_config.json b/champsim_config.json
index d8a33e13c6..248267442b 100644
--- a/champsim_config.json
+++ b/champsim_config.json
@@ -3,7 +3,7 @@
   "block_size": 64,
   "page_size": 4096,
   "heartbeat_frequency": 10000000,
-  "num_cores": 1,
+  "num_cores": 2,
 
   "ooo_cpu": [
     {
diff --git a/src/champsim.cc b/src/champsim.cc
index 405cb93273..ed11fe37a8 100644
--- a/src/champsim.cc
+++ b/src/champsim.cc
@@ -145,8 +145,8 @@ phase_stats do_phase(const phase_info& phase, environment& env, std::vector<trac
       // Phase complete
       next_phase_complete[cpu.cpu] = next_phase_complete[cpu.cpu] || (cpu.sim_instr() >= length);
 
-      //halt cpu if warmup
-      if(next_phase_complete[cpu.cpu] && is_warmup && !cpu.halt) {
+      // Halt CPUs during warmup once their instruction budget is met
+      if (next_phase_complete[cpu.cpu] && is_warmup && !cpu.halt) {
         cpu.halt = true;
         fmt::print("{} halting CPU {} at instruction {} cycle {} for remainder of phase\n", phase_name, cpu.cpu, cpu.sim_instr(), cpu.sim_cycle());
       }
@@ -158,8 +158,21 @@ phase_stats do_phase(const phase_info& phase, environment& env, std::vector<trac
           op.end_phase(cpu.cpu);
         }
 
-        fmt::print("{} finished CPU {} instructions: {} cycles: {} cumulative IPC: {:.4g} (Simulation time: {:%H hr %M min %S sec})\n", phase_name, cpu.cpu,
-                   cpu.sim_instr(), cpu.sim_cycle(), std::ceil(cpu.sim_instr()) / std::ceil(cpu.sim_cycle()), elapsed_time());
+        if (!is_warmup) {
+          // Simulation phase: true ROI, from roi_stats
+          auto roi_instr = cpu.roi_instr();
+          auto roi_cycle = cpu.roi_cycle();
+          auto roi_ipc = std::ceil(roi_instr) / std::ceil(roi_cycle);
+          fmt::print("{} finished CPU {} instructions: {} cycles: {} cumulative IPC: {:.4g} (Simulation time: {:%H hr %M min %S sec})\n",
+                    phase_name, cpu.cpu, roi_instr, roi_cycle, roi_ipc, elapsed_time());
+        } else {
+          // Warmup phase: just print using sim_instr/sim_cycle (per-phase progress)
+          auto w_instr = cpu.sim_instr();
+          auto w_cycle = cpu.sim_cycle();
+          auto w_ipc = std::ceil(w_instr) / std::ceil(w_cycle);
+          fmt::print("{} finished CPU {} instructions: {} cycles: {} cumulative IPC: {:.4g} (Simulation time: {:%H hr %M min %S sec})\n",
+                    phase_name, cpu.cpu, w_instr, w_cycle, w_ipc, elapsed_time());
+        }
       }
     }
 
@@ -167,9 +180,14 @@ phase_stats do_phase(const phase_info& phase, environment& env, std::vector<trac
   }
 
   for (O3_CPU& cpu : env.cpu_view()) {
-    fmt::print("{} complete CPU {} instructions: {} cycles: {} cumulative IPC: {:.4g} (Simulation time: {:%H hr %M min %S sec})\n", phase_name, cpu.cpu,
-               cpu.sim_instr(), cpu.sim_cycle(), std::ceil(cpu.sim_instr()) / std::ceil(cpu.sim_cycle()), elapsed_time());
-  }
+    if (!is_warmup) {
+      auto roi_instr = cpu.roi_instr();
+      auto roi_cycle = cpu.roi_cycle();
+      auto roi_ipc = std::ceil(roi_instr) / std::ceil(roi_cycle);
+      fmt::print("{} complete CPU {} instructions: {} cycles: {} cumulative IPC: {:.4g} (Simulation time: {:%H hr %M min %S sec})\n",
+                phase_name, cpu.cpu, roi_instr, roi_cycle, roi_ipc, elapsed_time());
+    }
+}
 
   phase_stats stats;
   stats.name = phase.name;
diff --git a/src/ooo_cpu.cc b/src/ooo_cpu.cc
index 76055330e2..f0a68e36fd 100644
--- a/src/ooo_cpu.cc
+++ b/src/ooo_cpu.cc
@@ -91,14 +91,18 @@ void O3_CPU::begin_phase()
 
 void O3_CPU::end_phase(unsigned finished_cpu)
 {
-  // Record where the phase ended (overwrite if this is later)
+  if (finished_cpu != this->cpu) {
+    return;
+  }
+
+  // Record where the phase ended for this CPU
   sim_stats.end_instrs = num_retired;
   sim_stats.end_cycles = current_time.time_since_epoch() / clock_period;
 
-  if (finished_cpu == this->cpu) {
-    finish_phase_instr = num_retired;
-    finish_phase_time = current_time;
+  finish_phase_instr = num_retired;
+  finish_phase_time = current_time;
 
+  if (!warmup) {
     roi_stats = sim_stats;
   }
 }