Promote peer-site 0x5dc1 companion lane

crates/rrt-runtime/src/smp.rs

@@ -1893,6 +1893,15 @@ pub struct SmpSavePlacedStructureRecordTripletEntryProbe {
     pub profile_open_marker_hex: String,
     pub profile_repeated_primary_name: String,
     pub profile_repeated_secondary_name: String,
+    pub profile_footer_relative_offset: usize,
+    pub profile_footer_relative_offset_hex: String,
+    pub profile_pre_footer_padding_len: usize,
+    #[serde(default)]
+    pub profile_pre_footer_padding_hex_bytes: Vec<String>,
+    #[serde(default)]
+    pub profile_companion_byte_u8: Option<u8>,
+    #[serde(default)]
+    pub profile_companion_byte_hex: Option<String>,
     pub profile_payload_dword: u32,
     pub profile_payload_dword_hex: String,
     pub profile_sentinel_i32: i32,
@@ -3572,6 +3581,24 @@ pub struct SmpSavePlacedStructureProfilePayloadDeltaSummaryEntry {
     pub count: usize,
 }
 
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+pub struct SmpSavePlacedStructureProfileFooterPaddingSummaryEntry {
+    pub padding_len: usize,
+    pub count: usize,
+    #[serde(default)]
+    pub sample_hex_bytes: Vec<String>,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+pub struct SmpSavePlacedStructureProfileCompanionByteSummaryEntry {
+    pub companion_byte_hex: String,
+    pub count: usize,
+    #[serde(default)]
+    pub sample_primary_names: Vec<String>,
+    #[serde(default)]
+    pub sample_secondary_names: Vec<String>,
+}
+
 #[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
 pub struct SmpPeriodicCompanyServiceTraceReport {
     pub profile_family: String,
@@ -3590,6 +3617,7 @@ pub struct SmpPeriodicCompanyServiceTraceReport {
     pub peer_site_selector_candidate_owner_strip: String,
     pub peer_site_selector_candidate_persisted_tag_hex: String,
     pub peer_site_selector_candidate_selector_lane: String,
+    pub peer_site_selector_candidate_companion_lane: String,
     pub peer_site_selector_candidate_class_identity_status: String,
     #[serde(default)]
     pub peer_site_selector_candidate_helper_linkage: Vec<String>,
@@ -3600,6 +3628,12 @@ pub struct SmpPeriodicCompanyServiceTraceReport {
     pub peer_site_selector_candidate_saved_payload_delta_summaries:
         Vec<SmpSavePlacedStructureProfilePayloadDeltaSummaryEntry>,
     #[serde(default)]
+    pub peer_site_selector_candidate_saved_footer_padding_summaries:
+        Vec<SmpSavePlacedStructureProfileFooterPaddingSummaryEntry>,
+    #[serde(default)]
+    pub peer_site_selector_candidate_saved_companion_byte_summaries:
+        Vec<SmpSavePlacedStructureProfileCompanionByteSummaryEntry>,
+    #[serde(default)]
     pub peer_site_restore_input_fields: Vec<String>,
     #[serde(default)]
     pub peer_site_runtime_input_fields: Vec<String>,
@@ -4288,6 +4322,89 @@ fn summarize_peer_site_selector_candidate_saved_payload_deltas(
     summaries
 }
 
+fn summarize_peer_site_selector_candidate_saved_footer_padding(
+    analysis: &SmpSaveCompanyChairmanAnalysisReport,
+) -> Vec<SmpSavePlacedStructureProfileFooterPaddingSummaryEntry> {
+    let Some(triplets) = analysis.placed_structure_record_triplets.as_ref() else {
+        return Vec::new();
+    };
+    let mut grouped = BTreeMap::<usize, (usize, BTreeSet<String>)>::new();
+    for entry in &triplets.entries {
+        let grouped_entry = grouped
+            .entry(entry.profile_pre_footer_padding_len)
+            .or_insert_with(|| (0, BTreeSet::new()));
+        grouped_entry.0 += 1;
+        if grouped_entry.1.len() < 4 {
+            grouped_entry
+                .1
+                .insert(entry.profile_pre_footer_padding_hex_bytes.join(","));
+        }
+    }
+    let mut summaries = grouped
+        .into_iter()
+        .map(|(padding_len, (count, sample_hex_bytes))| {
+            SmpSavePlacedStructureProfileFooterPaddingSummaryEntry {
+                padding_len,
+                count,
+                sample_hex_bytes: sample_hex_bytes.into_iter().collect(),
+            }
+        })
+        .collect::<Vec<_>>();
+    summaries.sort_by(|left, right| {
+        right
+            .count
+            .cmp(&left.count)
+            .then_with(|| left.padding_len.cmp(&right.padding_len))
+    });
+    summaries.truncate(6);
+    summaries
+}
+
+fn summarize_peer_site_selector_candidate_saved_companion_bytes(
+    analysis: &SmpSaveCompanyChairmanAnalysisReport,
+) -> Vec<SmpSavePlacedStructureProfileCompanionByteSummaryEntry> {
+    let Some(triplets) = analysis.placed_structure_record_triplets.as_ref() else {
+        return Vec::new();
+    };
+    let mut grouped = BTreeMap::<String, (usize, BTreeSet<String>, BTreeSet<String>)>::new();
+    for entry in &triplets.entries {
+        let Some(companion_byte_hex) = entry.profile_companion_byte_hex.as_ref() else {
+            continue;
+        };
+        let grouped_entry = grouped
+            .entry(companion_byte_hex.clone())
+            .or_insert_with(|| (0, BTreeSet::new(), BTreeSet::new()));
+        grouped_entry.0 += 1;
+        if grouped_entry.1.len() < 4 {
+            grouped_entry.1.insert(entry.primary_name.clone());
+        }
+        if grouped_entry.2.len() < 4 {
+            grouped_entry.2.insert(entry.secondary_name.clone());
+        }
+    }
+    let mut summaries = grouped
+        .into_iter()
+        .map(
+            |(companion_byte_hex, (count, primary_names, secondary_names))| {
+                SmpSavePlacedStructureProfileCompanionByteSummaryEntry {
+                    companion_byte_hex,
+                    count,
+                    sample_primary_names: primary_names.into_iter().collect(),
+                    sample_secondary_names: secondary_names.into_iter().collect(),
+                }
+            },
+        )
+        .collect::<Vec<_>>();
+    summaries.sort_by(|left, right| {
+        right
+            .count
+            .cmp(&left.count)
+            .then_with(|| left.companion_byte_hex.cmp(&right.companion_byte_hex))
+    });
+    summaries.truncate(8);
+    summaries
+}
+
 fn build_periodic_company_service_trace_report(
     analysis: &SmpSaveCompanyChairmanAnalysisReport,
 ) -> SmpPeriodicCompanyServiceTraceReport {
@@ -4303,6 +4420,7 @@ fn build_periodic_company_service_trace_report(
         "0x0045c150 -> 0x0045c310 -> 0x0045c36e -> 0x00456100 -> 0x00455b70".to_string();
     let peer_site_selector_candidate_persisted_tag_hex = "0x5dc1".to_string();
     let peer_site_selector_candidate_selector_lane = "[owner+0x23e]".to_string();
+    let peer_site_selector_candidate_companion_lane = "[owner+0x242]".to_string();
     let peer_site_selector_candidate_class_identity_status =
         "grounded_direct_local_helper_strip".to_string();
     let peer_site_selector_candidate_helper_linkage = vec![
@@ -4316,6 +4434,10 @@ fn build_periodic_company_service_trace_report(
         summarize_peer_site_selector_candidate_saved_payloads(analysis);
     let peer_site_selector_candidate_saved_payload_delta_summaries =
         summarize_peer_site_selector_candidate_saved_payload_deltas(analysis);
+    let peer_site_selector_candidate_saved_footer_padding_summaries =
+        summarize_peer_site_selector_candidate_saved_footer_padding(analysis);
+    let peer_site_selector_candidate_saved_companion_byte_summaries =
+        summarize_peer_site_selector_candidate_saved_companion_bytes(analysis);
     let peer_site_restore_input_fields = vec![
         "[site+0x3cc] saved placed-structure id feeding 0x62b2fc".to_string(),
         "[site+0x3d0] saved companion-region id from [placed+0x173] feeding 0x62b268".to_string(),
@@ -4624,13 +4746,19 @@ fn build_periodic_company_service_trace_report(
     );
     if !peer_site_selector_candidate_saved_payload_summaries.is_empty() {
         notes.push(format!(
-            "The periodic-company trace now also carries a compact save-side summary of the tagged 0x5dc1 placed-structure profile payload/status pairs already parsed from the 0x36b1 triplet seam; dominant current pair is {} / {} x{}, and dominant adjacent payload delta is {:?}.",
+            "The periodic-company trace now also carries a compact save-side summary of the tagged 0x5dc1 placed-structure profile payload/status pairs already parsed from the 0x36b1 triplet seam; dominant current pair is {} / {} x{}, dominant adjacent payload delta is {:?}, dominant one-byte companion lane is {:?}, and dominant pre-footer padding len is {:?}.",
             peer_site_selector_candidate_saved_payload_summaries[0].profile_payload_dword_hex,
             peer_site_selector_candidate_saved_payload_summaries[0].profile_status_kind,
             peer_site_selector_candidate_saved_payload_summaries[0].count,
             peer_site_selector_candidate_saved_payload_delta_summaries
                 .first()
-                .map(|entry| entry.delta_hex.as_str())
+                .map(|entry| entry.delta_hex.as_str()),
+            peer_site_selector_candidate_saved_companion_byte_summaries
+                .first()
+                .map(|entry| entry.companion_byte_hex.as_str()),
+            peer_site_selector_candidate_saved_footer_padding_summaries
+                .first()
+                .map(|entry| entry.padding_len)
         ));
     }
     notes.push(
@@ -4648,10 +4776,13 @@ fn build_periodic_company_service_trace_report(
         peer_site_selector_candidate_owner_strip,
         peer_site_selector_candidate_persisted_tag_hex,
         peer_site_selector_candidate_selector_lane,
+        peer_site_selector_candidate_companion_lane,
         peer_site_selector_candidate_class_identity_status,
         peer_site_selector_candidate_helper_linkage,
         peer_site_selector_candidate_saved_payload_summaries,
         peer_site_selector_candidate_saved_payload_delta_summaries,
+        peer_site_selector_candidate_saved_footer_padding_summaries,
+        peer_site_selector_candidate_saved_companion_byte_summaries,
         peer_site_restore_input_fields,
         peer_site_runtime_input_fields,
         peer_site_runtime_reconstruction_status,
@@ -14253,6 +14384,7 @@ fn parse_save_placed_structure_record_triplet_probe(
             ) {
                 if profile_close_marker == 0x00005dc2 {
                     matched_footer = Some((
+                        candidate_offset,
                         profile_payload_dword,
                         profile_sentinel_i32,
                         profile_close_marker,
@@ -14261,7 +14393,22 @@ fn parse_save_placed_structure_record_triplet_probe(
                 }
             }
         }
-        let (profile_payload_dword, profile_sentinel_i32, profile_close_marker) = matched_footer?;
+        let (
+            profile_footer_relative_offset,
+            profile_payload_dword,
+            profile_sentinel_i32,
+            profile_close_marker,
+        ) = matched_footer?;
+        let profile_pre_footer_padding = profile_payload
+            .get(trailer_offset..profile_footer_relative_offset)?
+            .iter()
+            .map(|byte| format!("0x{byte:02x}"))
+            .collect::<Vec<_>>();
+        let profile_companion_byte_u8 = if profile_pre_footer_padding.len() == 1 {
+            profile_payload.get(trailer_offset).copied()
+        } else {
+            None
+        };
         let (profile_status_kind, farm_growth_stage_index) =
             derive_save_placed_structure_profile_status(
                 &primary_name,
@@ -14289,6 +14436,13 @@ fn parse_save_placed_structure_record_triplet_probe(
             profile_open_marker_hex: format!("0x{profile_open_marker:08x}"),
             profile_repeated_primary_name,
             profile_repeated_secondary_name,
+            profile_footer_relative_offset,
+            profile_footer_relative_offset_hex: format!("0x{profile_footer_relative_offset:x}"),
+            profile_pre_footer_padding_len: profile_pre_footer_padding.len(),
+            profile_pre_footer_padding_hex_bytes: profile_pre_footer_padding,
+            profile_companion_byte_hex: profile_companion_byte_u8
+                .map(|byte| format!("0x{byte:02x}")),
+            profile_companion_byte_u8,
             profile_payload_dword,
             profile_payload_dword_hex: format!("0x{profile_payload_dword:08x}"),
             profile_sentinel_i32,
@@ -25035,6 +25189,22 @@ mod tests {
             triplet_probe.entries[0].profile_repeated_secondary_name,
             "StationSetA"
         );
+        assert_eq!(
+            triplet_probe.entries[0].profile_footer_relative_offset_hex,
+            "0x1b"
+        );
+        assert_eq!(triplet_probe.entries[0].profile_pre_footer_padding_len, 1);
+        assert_eq!(
+            triplet_probe.entries[0].profile_pre_footer_padding_hex_bytes,
+            vec!["0x00".to_string()]
+        );
+        assert_eq!(triplet_probe.entries[0].profile_companion_byte_u8, Some(0));
+        assert_eq!(
+            triplet_probe.entries[0]
+                .profile_companion_byte_hex
+                .as_deref(),
+            Some("0x00")
+        );
         assert_eq!(
             triplet_probe.entries[0].profile_payload_dword_hex,
             "0x0e373500"
@@ -25442,6 +25612,12 @@ mod tests {
                     profile_open_marker_hex: "0x00000000".to_string(),
                     profile_repeated_primary_name: "TunnelSTBrick_Section.3dp".to_string(),
                     profile_repeated_secondary_name: "Infrastructure".to_string(),
+                    profile_footer_relative_offset: 0,
+                    profile_footer_relative_offset_hex: "0x0".to_string(),
+                    profile_pre_footer_padding_len: 0,
+                    profile_pre_footer_padding_hex_bytes: Vec::new(),
+                    profile_companion_byte_u8: None,
+                    profile_companion_byte_hex: None,
                     profile_payload_dword: 0,
                     profile_payload_dword_hex: "0x00000000".to_string(),
                     profile_sentinel_i32: -1,
@@ -25471,6 +25647,12 @@ mod tests {
                     profile_open_marker_hex: "0x00000000".to_string(),
                     profile_repeated_primary_name: "TrackCapST_Cap.3dp".to_string(),
                     profile_repeated_secondary_name: "Infrastructure".to_string(),
+                    profile_footer_relative_offset: 0,
+                    profile_footer_relative_offset_hex: "0x0".to_string(),
+                    profile_pre_footer_padding_len: 0,
+                    profile_pre_footer_padding_hex_bytes: Vec::new(),
+                    profile_companion_byte_u8: None,
+                    profile_companion_byte_hex: None,
                     profile_payload_dword: 0,
                     profile_payload_dword_hex: "0x00000000".to_string(),
                     profile_sentinel_i32: -1,
@@ -27255,6 +27437,12 @@ mod tests {
                         profile_open_marker_hex: "0x00005dc1".to_string(),
                         profile_repeated_primary_name: "StationA".to_string(),
                         profile_repeated_secondary_name: "StationSetA".to_string(),
+                        profile_footer_relative_offset: 0,
+                        profile_footer_relative_offset_hex: "0x0".to_string(),
+                        profile_pre_footer_padding_len: 1,
+                        profile_pre_footer_padding_hex_bytes: vec!["0x01".to_string()],
+                        profile_companion_byte_u8: Some(1),
+                        profile_companion_byte_hex: Some("0x01".to_string()),
                         profile_payload_dword: 0x0e373880,
                         profile_payload_dword_hex: "0x0e373880".to_string(),
                         profile_sentinel_i32: -1,
@@ -27284,6 +27472,12 @@ mod tests {
                         profile_open_marker_hex: "0x00005dc1".to_string(),
                         profile_repeated_primary_name: "StationB".to_string(),
                         profile_repeated_secondary_name: "StationSetB".to_string(),
+                        profile_footer_relative_offset: 0,
+                        profile_footer_relative_offset_hex: "0x0".to_string(),
+                        profile_pre_footer_padding_len: 1,
+                        profile_pre_footer_padding_hex_bytes: vec!["0x00".to_string()],
+                        profile_companion_byte_u8: Some(0),
+                        profile_companion_byte_hex: Some("0x00".to_string()),
                         profile_payload_dword: 0x0e373500,
                         profile_payload_dword_hex: "0x0e373500".to_string(),
                         profile_sentinel_i32: -1,
@@ -27350,6 +27544,10 @@ mod tests {
             trace.peer_site_selector_candidate_selector_lane,
             "[owner+0x23e]"
         );
+        assert_eq!(
+            trace.peer_site_selector_candidate_companion_lane,
+            "[owner+0x242]"
+        );
         assert_eq!(
             trace.peer_site_selector_candidate_class_identity_status,
             "grounded_direct_local_helper_strip"
@@ -27373,6 +27571,14 @@ mod tests {
             trace.peer_site_selector_candidate_saved_payload_delta_summaries[0].delta_hex,
             "0x00000380"
         );
+        assert_eq!(
+            trace.peer_site_selector_candidate_saved_footer_padding_summaries[0].padding_len,
+            1
+        );
+        assert_eq!(
+            trace.peer_site_selector_candidate_saved_companion_byte_summaries[0].companion_byte_hex,
+            "0x00"
+        );
         assert_eq!(trace.peer_site_restore_input_fields.len(), 4);
         assert_eq!(trace.peer_site_runtime_input_fields.len(), 3);
         assert_eq!(

docs/rehost-queue.md

@@ -93,6 +93,11 @@ Working rule:
     almost entirely unique while the status kind stays `unset`, and the dominant adjacent payload
     delta is `0x00000780` across `1908` steps; grounded `q.gms` shows the same dominant adjacent
     delta `0x00000780` across `1868` steps
+  - the same trace now also promotes the one-byte `0x5dc1` companion lane explicitly: grounded
+    `p.gms` shows dominant companion byte `0x00` on `2023` rows with only `3` `0x01` rows, and
+    grounded `q.gms` shows dominant companion byte `0x00` on `2043` rows with only `14` `0x01`
+    rows; the old “pre-footer padding” hypothesis is now better understood as the probable
+    `[owner+0x242]` companion lane rather than anonymous slack bytes
   So the next owner question is no longer “what does the acquisition branch do?” or “which post-
   load owner replays linked-site refresh?” but “which concrete `0x00455b70` caller family applies
   to the live site rows, and which persisted lane becomes the selector bundle that ultimately
@@ -123,6 +128,10 @@ Working rule:
     (`dominant adjacent delta 0x780` on both `p.gms` and `q.gms`) rather than a compact selector
     family, so the next peer-site slice should treat that raw dword as a likely allocator/offset
     lane until a stronger selector interpretation appears
+  - use the new `0x5dc1` companion-byte summary in the same trace as positive evidence:
+    the probable `[owner+0x242]` lane is overwhelmingly `0x00` with a tiny `0x01` residue on both
+    grounded saves, so the next peer-site slice should treat that byte as a real typed companion
+    discriminator and ask which later `0x004014b0` / `0x00406050` predicates actually consume it
   - treat the peer-site selector seam itself as grounded enough for planning purposes
   - use the new structured restore/runtime field split in the same trace:
     restore subset