# Phase A diff report

**This report is the output of Phase A's diff harness. Divergences
shown here are INPUT for Phase B (first-divergence localization),
not findings of Phase A.** Phase A's job is to make the harness
itself correct, not to analyze what it surfaces.

## Summary

| canary_tid | ours_tid | matched | canary_total | ours_total | first_divergence_at | floating_create (c/o) | floating_wait (c/o) |
|---|---|---|---|---|---|---|---|
| 4 | 11 | 11 | 20000 | 11 | — | 0/0 | 0/0 |
| 6 | 1 | 105286 | 250000 | 108507 | 105286 | 2/0 | 4/0 |
| 7 | 2 | 32 | 32 | 33 | — | 0/0 | 0/0 |
| 12 | 7 | 4 | 20000 | 5 | 4 | 0/0 | 0/0 |
| 14 | 9 | 41 | 20000 | 77 | 41 | 0/0 | 0/0 |
| 15 | 10 | 16 | 20000 | 17 | — | 0/1 | 0/0 |

*`floating_create (c/o)` counts shared-global `handle.create` events absorbed by Phase C+18 cross-tid SID matching. `floating_wait (c/o)` counts `wait.begin` events on shared-global dispatchers absorbed by Phase C+21 (scheduling-jitter window — canary's contention slow path may fire while ours fast-paths or vice versa). See schema-v1.md §"Shared-global SIDs" and §"Wait-begin floating absorb".*

## canary_tid=4 → ours_tid=11

No divergence within the 11 compared events (canary has 20000, ours has 11).

## canary_tid=6 → ours_tid=1

First divergence at matched-prefix position 105286 (canary raw tid_event_idx=105298, ours raw tid_event_idx=105286): payload.ord: canary=441 ours=77

**Pre-context (last 5 matching events):**
```
  canary: [105293] kernel.call VdGetSystemCommandBuffer
  ours:   [105281] kernel.call VdGetSystemCommandBuffer
  canary: [105294] kernel.return VdGetSystemCommandBuffer
  ours:   [105282] kernel.return VdGetSystemCommandBuffer
  canary: [105295] import.call VdSwap
  ours:   [105283] import.call VdSwap
  canary: [105296] kernel.call VdSwap
  ours:   [105284] kernel.call VdSwap
  canary: [105297] kernel.return VdSwap
  ours:   [105285] kernel.return VdSwap
```

**Divergent event:**
```
  canary: [105298] import.call VdGetCurrentDisplayGamma
  ours:   [105286] import.call KeAcquireSpinLockAtRaisedIrql
```

**Next event after the divergence (if any):**
```
  canary: [105299] kernel.call VdGetCurrentDisplayGamma
  ours:   [105287] kernel.call KeAcquireSpinLockAtRaisedIrql
```

**Raw events (JSON):**
```json
{"deterministic": true, "engine": "canary", "guest_cycle": 0, "host_ns": 1598870700, "kind": "import.call", "payload": {"module": "xboxkrnl.exe", "name": "VdGetCurrentDisplayGamma", "ord": 441}, "schema_version": 1, "tid": 6, "tid_event_idx": 105298}
{"deterministic": true, "engine": "ours", "guest_cycle": 5577370, "host_ns": 490268717, "kind": "import.call", "payload": {"module": "xboxkrnl.exe", "name": "KeAcquireSpinLockAtRaisedIrql", "ord": 77}, "schema_version": 1, "tid": 1, "tid_event_idx": 105286}
```

## canary_tid=7 → ours_tid=2

No divergence within the 32 compared events (canary has 32, ours has 33).

## canary_tid=12 → ours_tid=7

First divergence at matched-prefix position 4 (canary raw tid_event_idx=4, ours raw tid_event_idx=4): [return_value mismatch] kernel.return name=KeWaitForSingleObject: canary=258 ours=0

**Pre-context (last 5 matching events):**
```
  canary: [0] import.call KeWaitForSingleObject
  ours:   [0] import.call KeWaitForSingleObject
  canary: [1] kernel.call KeWaitForSingleObject
  ours:   [1] kernel.call KeWaitForSingleObject
  canary: [2] handle.create sid=c49d8f0ab90401ea
  ours:   [2] handle.create sid=9559797117e919f0
  canary: [3] wait.begin {'handles_semantic_ids': ['c49d8f0ab90401ea'], 'timeout_ns': -30000000, 'alertable': False, 'wait_type': 'any'}
  ours:   [3] wait.begin {'handles_semantic_ids': ['9559797117e919f0'], 'timeout_ns': -30000000, 'alertable': False, 'wait_type': 'any'}
```

**Divergent event:**
```
  canary: [4] kernel.return KeWaitForSingleObject
  ours:   [4] kernel.return KeWaitForSingleObject
```

**Next event after the divergence (if any):**
```
  canary: [5] import.call RtlEnterCriticalSection
  ours:   <end of stream>
```

**Raw events (JSON):**
```json
{"deterministic": true, "engine": "canary", "guest_cycle": 0, "host_ns": 1582904700, "kind": "kernel.return", "payload": {"name": "KeWaitForSingleObject", "return_value": 258, "side_effects": [], "status": "0x00000102"}, "schema_version": 1, "tid": 12, "tid_event_idx": 4}
{"deterministic": true, "engine": "ours", "guest_cycle": 30, "host_ns": 487797864, "kind": "kernel.return", "payload": {"name": "KeWaitForSingleObject", "return_value": 0, "side_effects": [], "status": "0x00000000"}, "schema_version": 1, "tid": 7, "tid_event_idx": 4}
```

## canary_tid=14 → ours_tid=9

First divergence at matched-prefix position 41 (canary raw tid_event_idx=41, ours raw tid_event_idx=41): payload.ord: canary=503 ours=293

**Pre-context (last 5 matching events):**
```
  canary: [36] kernel.call KeReleaseSpinLockFromRaisedIrql
  ours:   [36] kernel.call KeReleaseSpinLockFromRaisedIrql
  canary: [37] kernel.return KeReleaseSpinLockFromRaisedIrql
  ours:   [37] kernel.return KeReleaseSpinLockFromRaisedIrql
  canary: [38] import.call KfLowerIrql
  ours:   [38] import.call KfLowerIrql
  canary: [39] kernel.call KfLowerIrql
  ours:   [39] kernel.call KfLowerIrql
  canary: [40] kernel.return KfLowerIrql
  ours:   [40] kernel.return KfLowerIrql
```

**Divergent event:**
```
  canary: [41] import.call XAudioGetVoiceCategoryVolumeChangeMask
  ours:   [41] import.call RtlEnterCriticalSection
```

**Next event after the divergence (if any):**
```
  canary: [42] kernel.call XAudioGetVoiceCategoryVolumeChangeMask
  ours:   [42] kernel.call RtlEnterCriticalSection
```

**Raw events (JSON):**
```json
{"deterministic": true, "engine": "canary", "guest_cycle": 0, "host_ns": 1770114500, "kind": "import.call", "payload": {"module": "xboxkrnl.exe", "name": "XAudioGetVoiceCategoryVolumeChangeMask", "ord": 503}, "schema_version": 1, "tid": 14, "tid_event_idx": 41}
{"deterministic": true, "engine": "ours", "guest_cycle": 417, "host_ns": 717989594, "kind": "import.call", "payload": {"module": "xboxkrnl.exe", "name": "RtlEnterCriticalSection", "ord": 293}, "schema_version": 1, "tid": 9, "tid_event_idx": 41}
```

## canary_tid=15 → ours_tid=10

No divergence within the 16 compared events (canary has 20000, ours has 17).