#!/usr/bin/env bash
set -euo pipefail

# perf-stat triad (HAKMEM/System/mimalloc) for bench_tiny_hot at a single size/batch/cycles
# Collects cycles/instructions/branches/branch-misses/L1-dcache-load-misses (CSV via perf -x ,)
# Usage: scripts/run_perf_hot_triad.sh [size] [batch] [cycles] [reps]
#   size  : bytes (default 32)
#   batch : batch size (default 100)
#   cycles: loop cycles per op (default 50000)
#   reps  : perf repetitions (default 3)

ROOT_DIR=$(cd "$(dirname "$0")/.." && pwd)
cd "$ROOT_DIR"

size=${1:-32}
batch=${2:-100}
cycles=${3:-50000}
reps=${4:-3}

echo "[build] benches (fast + mi)"
make -s bench_fast bench_tiny_hot_mi >/dev/null

# Ensure LD_LIBRARY_PATH is defined (set -u safety)
export LD_LIBRARY_PATH="${LD_LIBRARY_PATH:-}"
MI_LIBDIR="$ROOT_DIR/mimalloc-bench/extern/mi/out/release"

TS=$(date +%Y%m%d_%H%M%S)
OUTDIR="bench_results/perf_hot_triad_${TS}"
mkdir -p "$OUTDIR"

echo "[info] size=$size batch=$batch cycles=$cycles reps=$reps"
echo "[info] results → $OUTDIR"

run_perf() {
  local alloc="$1"; shift
  local bin="$1"; shift
  local tag="$alloc"_s${size}_b${batch}_c${cycles}
  local log="$OUTDIR/${tag}.perf.csv"
  echo "[perf] $tag"
  if [[ "$alloc" == "mimalloc" ]]; then
    LD_LIBRARY_PATH="$LD_LIBRARY_PATH:$MI_LIBDIR" \
      perf stat -x , -r "$reps" -e cycles,instructions,branches,branch-misses,L1-dcache-load-misses \
        "$bin" "$size" "$batch" "$cycles" 1>/dev/null 2>"$log" || true
  else
    perf stat -x , -r "$reps" -e cycles,instructions,branches,branch-misses,L1-dcache-load-misses \
      "$bin" "$size" "$batch" "$cycles" 1>/dev/null 2>"$log" || true
  fi
}

run_perf hakmem ./bench_tiny_hot_hakmem
run_perf system ./bench_tiny_hot_system
run_perf mimalloc ./bench_tiny_hot_mi

echo "[done] perf CSVs under: $OUTDIR"
ls -1 "$OUTDIR" | sed -n '1,20p'