research: post-swept-tube near-ready cost account (L103, measurement only)

FI/TN LOD0-2 W12 worker CPU 13.9/12.2 s: passages 40/35%, far-shell refinement (HasDownwardHit/
HasUpwardHit ~1.7-1.9 s) in 'other' 27/30%, support 14/13%, dispatch 8%, base field 6%, bands 6%.
Workers 28%/24% idle during LOD0-1. Near-ready W12: SW 0.77, FI 1.51, TN 1.38, VS 0.96 s.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016dhxM43dnWvUu2B5Ph1iG1

Standalone/Research/WorldAssemblerM3/Linux103/AnalyzeL103Symbols.py

@@ -0,0 +1,119 @@
+#!/usr/bin/env python3
+"""Attribute FI/TN L77 sample PCs to current-source functions and work areas."""
+from __future__ import annotations
+
+import csv
+import json
+import re
+import subprocess
+from collections import Counter
+from pathlib import Path
+
+ROOT = Path(__file__).resolve().parents[4]
+OUT = ROOT / "Saved/Linux/l103/census"
+BINARY = ROOT / "Saved/Linux/l103/profile-bin/VoxelForgeCoreHeadless-l103-profile-clang"
+SAMPLE = re.compile(
+    r"^\[L77Sample\] pc=(0x\w+) lod=(\d+) stage=(\S+) route=(\S+) "
+    r"phase=(\S+) halo=(\d+) weight=(\d+)$", re.M)
+TARGETS = {
+    "sweep_base_prepare": "prepareSweptTubeBase",
+    "sweep_lookup": "sweptSample",
+    "exact_route_visit": "VisitNearestPassage",
+    "miss_reach_bound": "PassagePotentialWithinNode",
+    "far_shell_down_hit": "HasDownwardHit",
+    "far_shell_up_hit": "HasUpwardHit",
+}
+
+
+def load_samples() -> tuple[list[dict], set[str]]:
+    rows, pcs = [], set()
+    for stratum in ("FI", "TN"):
+        for replicate in (1, 2, 3):
+            log = OUT / f"{stratum.lower()}-r{replicate}.log"
+            content = log.read_text(encoding="utf-8", errors="replace")
+            for pc, lod, stage, route, phase, halo, weight in SAMPLE.findall(content):
+                if int(lod) > 2:
+                    continue
+                pcs.add(pc)
+                rows.append({"stratum": stratum, "replicate": replicate, "pc": pc,
+                             "lod": int(lod), "stage": stage, "route": route,
+                             "phase": phase, "weight": int(weight)})
+    return rows, pcs
+
+
+def symbolize(pcs: set[str]) -> dict[str, list[dict]]:
+    command = ["llvm-symbolizer-19", "--demangle", "--inlines", "--output-style=JSON",
+               f"--obj={BINARY}"]
+    result = subprocess.run(command, input="\n".join(sorted(pcs)) + "\n",
+                            capture_output=True, text=True, check=True)
+    decoder = json.JSONDecoder()
+    offset = 0
+    output = {}
+    while offset < len(result.stdout):
+        while offset < len(result.stdout) and result.stdout[offset].isspace():
+            offset += 1
+        if offset == len(result.stdout):
+            break
+        item, offset = decoder.raw_decode(result.stdout, offset)
+        output[item["Address"]] = item.get("Symbol", [])
+    if output.keys() != pcs:
+        raise RuntimeError(f"symbolizer resolved {len(output)}/{len(pcs)} sampled PCs")
+    return output
+
+
+def write_csv(path: Path, rows: list[dict]) -> None:
+    with path.open("w", encoding="utf-8", newline="") as stream:
+        writer = csv.DictWriter(stream, fieldnames=list(rows[0]))
+        writer.writeheader()
+        writer.writerows(rows)
+
+
+def main() -> int:
+    if not BINARY.is_file():
+        raise SystemExit(f"missing profile binary: {BINARY}")
+    samples, pcs = load_samples()
+    symbols = symbolize(pcs)
+    function_totals = Counter()
+    target_totals = Counter()
+    for sample in samples:
+        frames = symbols[sample["pc"]]
+        top_function = frames[0].get("FunctionName", "?") if frames else "?"
+        function_totals[(sample["stratum"], sample["stage"], sample["phase"],
+                         top_function)] += sample["weight"]
+        seen = set()
+        for name, token in TARGETS.items():
+            matches = [frame for frame in frames if token in frame.get("FunctionName", "")]
+            if not matches:
+                continue
+            frame = matches[0]
+            line = int(frame.get("Line", 0))
+            category = name
+            if name == "sweep_base_prepare":
+                category = ("sweep_prepare_base" if 14249 <= line <= 14435 else
+                            "sweep_prepare_detail" if 14436 <= line <= 14521 else
+                            "sweep_prepare_unlocated")
+            key = (sample["stratum"], sample["stage"], sample["phase"], category)
+            if key not in seen:
+                target_totals[key] += sample["weight"]
+                seen.add(key)
+
+    by_function = [
+        {"stratum": stratum, "stage": stage, "phase": phase,
+         "weighted_ticks": ticks, "top_function": function}
+        for (stratum, stage, phase, function), ticks in
+        sorted(function_totals.items(), key=lambda item: (item[0][:3], -item[1]))
+    ]
+    by_target = [
+        {"stratum": stratum, "stage": stage, "phase": phase,
+         "work_area": target, "weighted_ticks": ticks}
+        for (stratum, stage, phase, target), ticks in sorted(target_totals.items())
+    ]
+    write_csv(OUT / "symbol-function-totals.csv", by_function)
+    write_csv(OUT / "symbol-work-area-totals.csv", by_target)
+    print(f"[L103SymbolAnalysis] samples={len(samples)} unique_pcs={len(pcs)} "
+          f"functions={len(by_function)} work_areas={len(by_target)}")
+    return 0
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())