re: auto-label all opcode dispatch handlers from FUN_00413860
Extract op->real-handler map (handler(op)=ctx[0x26c93+op]) from the registration routine's override stores; ghidra_handler_map.py + build/op-handler-map.json (420 overrides). Cross-check vs opcodes.toml found 0 real drift. One-shot Ghidra pass then labeled the /v2 image: 281 raw FUN_/LAB_ handlers -> op_0xNN_handler, 107 bare VAs -> functions, 31 hand-named preserved, opcode plate comment on every handler. Includes the Task A spec + plan and the two-program (/v2 vs SMM) gotcha. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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# RE Tooling: Handler Labeling + IAT Reconstruction — Implementation Plan
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> **For agentic workers:** REQUIRED SUB-SKILL: Use superpowers:subagent-driven-development (recommended) or superpowers:executing-plans to implement this plan task-by-task. Steps use checkbox (`- [ ]`) syntax for tracking.
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**Goal:** Eliminate two recurring native-RE taxes — Kelebek VA-drift and unnamed imports — by (A) auto-labeling every opcode dispatch handler in the Ghidra image and (B) grafting reconstructed IAT names onto that same image.
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**Architecture:** Two independent workstreams against the existing annotated Ghidra program (`range_00400000.bin`, base `0x400000`), driven over the ghidra-mcp bridge. A is fully static (no running game). B needs a live `AGE.EXE` for `pe-sieve32`. A pure-Python parser does the mechanical work in both; MCP calls apply the results to the image; annotations are always preserved.
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**Tech Stack:** Python 3.11 (`py -3.11 -X utf8`), ghidra-mcp bridge (Ghidra 12.1.2), `bin/pe-sieve32.exe`, `pytest`.
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## Global Constraints
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- Run Python as `py -3.11 -X utf8 tools/<name>.py …` (utf8 mandatory on Windows).
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- Tools import `tools/paths.py`; never hard-code paths.
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- Engine image: Raw Binary, `x86:LE:32:default`, Image Base `0x400000`; VA→file offset = `VA − 0x400000`.
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- Dispatch identity: `handler(op) = ctx[0x26c93 + op] = *(ctx + 0x9b24c + op*4)`; overrides written in `FUN_00413860`; default handler = `FUN_004162b0`.
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- **Never hand-edit generated files** (`build/*`); rebuild via the owning tool.
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- **Preserve annotations** — never reimport the program in B; never rename an already-named handler in A.
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- End every image-mutating task with `save_program` (MCP `mcp__ghidra__save_program`).
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- `pe-sieve32.exe` runs from **PowerShell** (Git Bash mangles `/flags`).
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- Deferred / out of scope: outer-loop RE (wider dump / live debugger), STL/CRT demangling.
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---
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## Task A: Auto-label every dispatch handler
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**Files:**
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- Create: `tools/ghidra_handler_map.py` (parser + JSON emitter + opcodes.toml cross-check)
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- Create: `tools/test_ghidra_handler_map.py` (unit test for the parser)
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- Create: `build/op-handler-map.json` (generated — do not hand-edit)
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- Create: `scratchpad` fixture `FUN_00413860.disasm.txt` (captured disassembly, input to the parser)
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- Modify: `docs/engine-re.md` (dispatch-table section links the generated map)
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- Modify: `docs/tools-reference.md` (document `ghidra_handler_map.py`)
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**Interfaces:**
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- Produces: `parse_overrides(disasm_lines: list[str]) -> dict[int, int]` mapping `op → handler_va`, excluding the default handler `0x4162b0`.
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- Produces: `build/op-handler-map.json` shape `{ "0x1ac": {"handler": "0x427fb0"}, ... }`.
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- Consumes (Step A5): `vm-map/opcodes.toml` handler VAs for cross-check.
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- [ ] **Step A1: Capture `FUN_00413860` disassembly as a parser fixture**
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Via MCP against the open program, dump the registration routine's instructions to a fixture file:
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Run: `mcp__ghidra__disassemble_function` with `address="0x413860"` (or `get_function_pcode` if disasm is cleaner), save raw text to `scratchpad/FUN_00413860.disasm.txt`.
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Expected: a long list of `MOV dword ptr [<reg> + 0x9b...], 0x4?????` stores plus a default-fill loop.
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- [ ] **Step A2: Write the failing parser test**
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```python
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# tools/test_ghidra_handler_map.py
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from ghidra_handler_map import parse_overrides
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def test_parses_known_override_anchors():
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# Minimal fixture lines in the exact shape captured in A1.
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lines = [
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"MOV dword ptr [EAX + 0x9b8fc],0x427fb0", # 0x9b8fc = 0x9b24c + 0x1ac*4 -> op 0x1ac
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"MOV dword ptr [EAX + 0x9b688],0x420ec0", # 0x9b688 = 0x9b24c + 0xc8*4 -> op 0xc8
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"MOV dword ptr [EAX + 0x100],0x4162b0", # not in table window -> ignored
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]
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m = parse_overrides(lines)
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assert m[0x1ac] == 0x427fb0
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assert m[0xc8] == 0x420ec0
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assert 0x4162b0 not in m.values() # default handler excluded
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def test_excludes_default_handler_writes():
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lines = ["MOV dword ptr [EAX + 0x9b24c],0x4162b0"] # op 0x0 default fill
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assert parse_overrides(lines) == {}
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```
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- [ ] **Step A3: Run the test to verify it fails**
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Run: `py -3.11 -X utf8 -m pytest tools/test_ghidra_handler_map.py -v`
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Expected: FAIL — `ModuleNotFoundError`/`cannot import name 'parse_overrides'`.
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- [ ] **Step A4: Implement the parser**
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```python
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# tools/ghidra_handler_map.py
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import json, re, sys
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import paths # path anchor
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TABLE_BASE = 0x9b24c # byte offset of ctx[0x26c93]
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TABLE_SPAN = 0x400 * 4 # 1024 word slots
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DEFAULT_HANDLER = 0x4162b0
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_STORE = re.compile(
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r"MOV\s+dword ptr\s+\[\w+\s*\+\s*(0x[0-9a-fA-F]+)\]\s*,\s*(0x[0-9a-fA-F]+)")
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def parse_overrides(lines):
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out = {}
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for ln in lines:
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m = _STORE.search(ln)
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if not m:
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continue
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disp = int(m.group(1), 16)
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va = int(m.group(2), 16)
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if not (TABLE_BASE <= disp < TABLE_BASE + TABLE_SPAN):
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continue
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if (disp - TABLE_BASE) % 4 != 0:
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continue
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op = (disp - TABLE_BASE) // 4
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if va == DEFAULT_HANDLER:
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continue
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out[op] = va
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return out
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def build(disasm_path, out_path):
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lines = disasm_path.read_text(encoding="utf-8").splitlines()
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m = parse_overrides(lines)
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data = {hex(op): {"handler": hex(va)} for op, va in sorted(m.items())}
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out_path.write_text(json.dumps(data, indent=2), encoding="utf-8")
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return m
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if __name__ == "__main__":
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from pathlib import Path
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disasm = Path(sys.argv[1])
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out = paths.BUILD / "op-handler-map.json"
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m = build(disasm, out)
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print(f"{len(m)} overrides -> {out}")
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```
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- [ ] **Step A5: Run the test to verify it passes**
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Run: `py -3.11 -X utf8 -m pytest tools/test_ghidra_handler_map.py -v`
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Expected: PASS (both tests).
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- [ ] **Step A6: Generate the real map and verify anchors**
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Run: `py -3.11 -X utf8 tools/ghidra_handler_map.py scratchpad/FUN_00413860.disasm.txt`
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Then inspect `build/op-handler-map.json` and assert the four known anchors:
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- `0x1ac → 0x427fb0`, `0x1a2 → 0x42d360`, `0x215 → 0x42a0b0`, `0xc8 → 0x420ec0`.
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Expected: all four present and exact; total override count is reported and plausible (record it in the doc). If any anchor is missing, the A1 capture missed stores (e.g. non-`MOV`/computed writes) — re-capture with `get_function_pcode` and widen the regex before proceeding.
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- [ ] **Step A7: Cross-check against `opcodes.toml` (report only, no auto-edit)**
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Extend `ghidra_handler_map.py` with a `--check` mode that loads each opcode's recorded handler VA from `vm-map/opcodes.toml` (where present) and prints every op where `toml_handler != derived_handler`.
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Run: `py -3.11 -X utf8 tools/ghidra_handler_map.py scratchpad/FUN_00413860.disasm.txt --check`
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Expected: a (possibly empty) disagreement list. **Do not edit opcodes.toml here** — capture the list in the task notes for human reconciliation (each disagreement is a latent VA-drift bug).
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- [ ] **Step A8: Apply annotations to the image (preserve good names)**
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For each `(op, va)` in the map, drive MCP:
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1. `get_function_by_address(va)` — read the current name.
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2. If the name is missing or matches `^(FUN_|LAB_)` → `create_function` (if absent) then `rename_function_by_address(va, f"op_0x{op:x}_handler")`.
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3. If the name is already descriptive (e.g. `gfx_op_*`, `sleep_op_*`, `call_script*`) → **do not rename**.
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4. Either way `set_plate_comment(va, f"opcode 0x{op:x} dispatch handler; ctx[0x26c93+op] in FUN_00413860")` — appending, not replacing an existing decode comment.
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Expected: every raw handler gets an `op_0xNN_handler` name; every previously-named handler keeps its name.
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- [ ] **Step A9: Verify no clobbers, then save**
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Re-read the four anchors and 3 previously-named handlers via `get_function_by_address`; confirm named ones are unchanged and raw ones now carry `op_0x…`.
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Run: `mcp__ghidra__save_program`.
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Expected: save succeeds; spot-checks pass.
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- [ ] **Step A10: Update docs and commit**
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Edit `docs/engine-re.md` dispatch-table section to reference `build/op-handler-map.json` (the full op→handler map, generated) instead of listing ops by hand; note the total override count and any A7 disagreements. Add `ghidra_handler_map.py` to `docs/tools-reference.md`.
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```bash
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git add tools/ghidra_handler_map.py tools/test_ghidra_handler_map.py build/op-handler-map.json docs/engine-re.md docs/tools-reference.md
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git commit -m "re: auto-label all opcode dispatch handlers from FUN_00413860"
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```
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---
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## Task B: Reconstruct the IAT and graft named imports
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**Prerequisite:** a running `AGE.EXE` instance (needed by `pe-sieve32`).
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**Files:**
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- Create: `tools/apply_imports.py` (parse pe-sieve import report → `{thunk_addr: "dll!Func"}`)
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- Create: `tools/test_apply_imports.py` (unit test for the report parser)
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- Create: `build/pe-sieve/` (pe-sieve output dir — reconstructed module + import report)
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- Modify: `docs/engine-re.md` (IAT-reconstruction runbook + fallback usage, if taken)
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- Modify: `docs/tools-reference.md` (document `apply_imports.py`)
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**Interfaces:**
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- Consumes: pe-sieve's import report text.
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- Produces: `parse_import_report(text: str) -> dict[int, str]` mapping `thunk_va → "dll!Function"`.
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- [ ] **Step B1: Run pe-sieve against the live game**
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Find the PID, then from **PowerShell**:
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```powershell
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$p = Get-Process AGE
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bin\pe-sieve32.exe /pid $p.Id /imp 3 /dmode 3 /dir build\pe-sieve
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```
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Expected: `build/pe-sieve/` contains the reconstructed module and an import report (`*.imports.txt`/tag file). Note the report's exact format for B2.
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- [ ] **Step B2: Write the failing import-report parser test**
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```python
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# tools/test_apply_imports.py
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from apply_imports import parse_import_report
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def test_parses_thunk_to_named_import():
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# Fixture lines in the EXACT shape observed in B1 (adjust to pe-sieve's real format).
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text = "\n".join([
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"0x00456120: kernel32.dll.CreateFileA",
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"0x00456124: kernel32.dll.ReadFile",
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])
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m = parse_import_report(text)
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assert m[0x456120] == "kernel32.dll!CreateFileA"
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assert m[0x456124] == "kernel32.dll!ReadFile"
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```
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- [ ] **Step B3: Run the test to verify it fails**
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Run: `py -3.11 -X utf8 -m pytest tools/test_apply_imports.py -v`
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Expected: FAIL — import error.
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- [ ] **Step B4: Implement the report parser**
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Implement `parse_import_report(text)` in `tools/apply_imports.py` to match the real B1 format (the fixture above is a placeholder shape — reconcile the regex to pe-sieve's actual columns). Return `{thunk_va: "dll!Func"}`.
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Run: `py -3.11 -X utf8 -m pytest tools/test_apply_imports.py -v`
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Expected: PASS.
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- [ ] **Step B5: Graft names onto the existing program**
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For each `(thunk_va, "dll!Func")`, drive MCP against the current annotated program (do **not** reimport): apply the name at the IAT thunk via the appropriate label/reference/external-location API (try `create_label`; if the thunk should be an external function, use the external-location API). Verify one call site reads as a named call:
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- Save-path handler (`0x1ac` region) → named `CreateFileA`/`SetFilePointer`.
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Expected: at least the save/resolver-chain sites (`FUN_0040e980`/`FUN_0044f390`) show named `CreateFileA`/`SetFilePointer`/`ReadFile`; the `sleep` timer source shows a `timeGetTime`-class name.
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- [ ] **Step B6: Fallback branch (only if B5 is an ordeal)**
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If thunk addresses don't line up or MCP can't set externals cleanly, stop grafting: import `build/pe-sieve/<module>` as a **second, clean Ghidra program** (Format PE), keep it open alongside ours, and use it purely as a name-lookup reference — port import names into our annotated program by hand as each function is touched. Document the two-program workflow in `docs/engine-re.md`'s runbook. (This preserves all annotations either way.)
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- [ ] **Step B7: Apply the Win32 data-type archive**
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Apply Ghidra's bundled Win32 type archive so named imports carry signatures (via the Data Type Manager / MCP `import_data_types` if exposed). Verify `CreateFileA` shows a typed prototype at a call site.
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Expected: named imports carry parameter types.
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- [ ] **Step B8: Save, verify annotations intact, update docs, commit**
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Confirm a sample of pre-existing renames/plate comments still present (`get_function_by_address` on `gfx_op_0x215_register_query`, `sleep_op_0xc8`). Run `mcp__ghidra__save_program`.
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Edit `docs/engine-re.md` (runbook: IAT reconstruction is done; note graft vs fallback) and `docs/tools-reference.md` (`apply_imports.py`).
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```bash
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git add tools/apply_imports.py tools/test_apply_imports.py docs/engine-re.md docs/tools-reference.md
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git commit -m "re: reconstruct IAT via pe-sieve and graft named imports"
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```
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---
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## Self-Review
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**Spec coverage:**
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- A (handler labeling): Task A1–A10 — parser, cross-check (A7), preserve-names (A8), anchors (A6), docs (A10). ✓
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- B (IAT graft + fallback + type lib): B1–B8, fallback = B6, type archive = B7. ✓
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- Sequencing (A first, static; B needs game): task order + B prerequisite. ✓
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- Deferred outer-loop RE: Global Constraints. ✓
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**Placeholder scan:** The B4/B2 note "reconcile regex to pe-sieve's actual format" is intentional — the exact report columns are only knowable after B1 runs; the fixture shows the target shape and B4 adjusts it. Not a hidden TODO. No other placeholders.
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**Type consistency:** `parse_overrides(list[str]) -> dict[int,int]` and `parse_import_report(str) -> dict[int,str]` are each used consistently by their `build`/graft consumers. Handler-name pattern `op_0xNN_handler` used identically in A8/A9.
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