Cesarus85--mjolnir-vr/docs/object_matching_logs

Object exact-match strategy logs

Every object that receives implementation or matching work must maintain one Markdown ledger in this directory. The filename is the object name with _obj.md, for example players_obj.md.

General techniques that apply across translation units belong in docs/exact_match_acceleration_playbook.md; object-specific measurements stay in the individual ledger.

The purpose is to make matching work cumulative. A new lane must be able to distinguish an untried evidence-backed source shape from a spelling that has already compiled to the same bytes.

Required contents

Each ledger must include:

1. Scope and provenance
   • source translation unit and target object;
   • exact compiler identity and flags;
   • target-build provenance used for names, layouts, or source topology.
2. Validated baseline
   • exact/total function count and padded code bytes;
   • exact/total data sections and bytes;
   • for every residual: target/base size, relocation count, normalized hash, and first meaningful divergence.
3. Accepted controls
   • the source shapes retained in production;
   • why each shape is supported by binary or provenance evidence.
4. Experiment matrix
   • every meaningful source shape tested;
   • resulting size, relocations, normalized hash, first divergence, and sibling-regression result;
   • whether it was retained or reverted.
5. Do-not-repeat list
   • equivalent spellings or compiler-control attempts already exhausted;
   • unsafe or prohibited techniques.
6. Residual classification
   • source/topology, ABI/register, scheduling, ownership/relocation, data, or unresolved;
   • clearly separate measured fact from inference.
7. Reopen criteria
   • the exact new evidence that would justify spending another lane.
8. Disposition
   • strict exact and eligible for Matching, still active, or rigorously parked;
   • never grant credit from a fuzzy percentage, equal size alone, or semantic plausibility.

Lane rules

• Update the ledger after every bounded experiment batch, not only at handoff.
• Rebuild with XDK 3911 and the repository flags after each retained change.
• Gate every function and owned data section with the hardened comparator.
• Run the whole-translation-unit regression sweep before committing.
• Revert failed source shapes immediately.
• Do not use inline assembly, volatile byte forcing, undefined behavior, object-byte patches, or compiler-flag changes.
• A parked residual must preserve enough evidence for another agent to reproduce the classification without redoing the full search.
• Label a defect BUG (original) only when January binary/source evidence proves the defective behavior belongs to the original game. A mistake or omission in our reconstruction is not an original bug. Preserve proven original behavior in the matching build and document the corrected-build alternative in a comment without changing the matching token/line shape.
• When retroactively documenting an old lane, state which experiment details were not preserved. Never manufacture source variants, hashes, or outcomes to make a historical matrix look complete.

Minimal experiment row

| ID | Source shape | Size T/B | Relocs T/B | Base hash | First divergence | Siblings | Decision |
|---|---|---:|---:|---|---|---|---|
| E01 | ... | `0x.../0x...` | `N/N` | `...` | `+0x...: ...` | `K/K exact` | reverted |