Files
OpenMaidEngine/engine/Age.Engine/Diagnostics/JsonOffsetTraceSink.cs
gamer147 f2936cbf36 feat(engine): --trace-json emitter for the differential oracle
JsonOffsetTraceSink records every executed instruction offset (bytecode word
index) of one target script, in order, filtered to the scene's own frame
(call-script subroutines excluded) to match the Frida engine tracer's
per-codebase filter. Wired as 'trace <SCENE.BIN> [--boot] --trace-json <out>'.
Observe-only; sweep path and trace parity untouched. +2 xUnit tests.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-07-09 11:20:23 -04:00

31 lines
1.4 KiB
C#

using System.Collections.Generic;
namespace Age.Engine.Diagnostics;
/// <summary>Records the script-relative offset of every instruction executed in one target script, in
/// execution order — the VM side of the differential offset-path oracle (docs/engine-re.md). Offsets are
/// the instruction's <see cref="Model.Instruction.Offset"/> (the bytecode WORD index, same unit the engine
/// tracer emits as <c>(pc-codebase)/4</c>), so the two sequences are directly comparable.
///
/// Filters to the target frame: only Step events whose innermost running script is the target are recorded,
/// so call-script subroutines into OTHER scripts are excluded — matching the engine trace's per-codebase
/// filter, which isolates the scene from boot/system scripts. Observe-only (emits nothing, touches no VM
/// state) so trace parity is preserved.</summary>
public sealed class JsonOffsetTraceSink : TraceSinkBase
{
private readonly string _target;
private readonly List<int> _offsets = new();
public JsonOffsetTraceSink(string targetScript) { _target = targetScript; }
/// <summary>Executed offsets of the target script, in order.</summary>
public IReadOnlyList<int> Offsets => _offsets;
public override bool TracingSteps => true;
protected override void OnEvent(in TraceEvent e)
{
if (e.Kind == TraceEventKind.Step && CurrentScript == _target && e.Ins is { } ins)
_offsets.Add(ins.Offset);
}
}