feat(igla): Wave Loop 883 — module-scope [585][2]^6 Pt non-power-of-two outer-dimension array-of-struct variable from call with indexed signed writes

.claude/plans/wave-loop-884.md

@@ -0,0 +1,65 @@
+# Wave Loop 884 Plan
+
+**Date:** 2026-08-06
+**Issue:** TBD (to be created when W883 lands)
+**Branch:** `wave-loop-884` (from `wave-loop-883` HEAD because earlier waves' PRs remain open)
+**Parent:** Wave Loop 883 (`[585][2]^6 Pt`, issue #1814, PR #1815)
+
+## Goal
+
+Continue the mechanical packed-vector array-of-struct ladder past the 1-MiBit line.
+Close Wave Loop 884 by validating a module-scope `[N][2]^6 Pt` packed array-of-struct
+variable initialized from a function call, with indexed signed field writes and
+`assert_eq` read-back in a `bench` block.
+
+## Recommended variant — A
+
+Keep the module-scope odd outer-dimension ladder:
+`[587][2]^6 Pt` non-power-of-two outer-dimension array-of-struct variable from call
+with indexed signed writes.
+
+- `OUTER = 587`, `MID_IDX = 293`
+- Total elements: `587 × 64 = 37,568`
+- Packed vector width: `37,568 × 32 = 1,202,176` bits (~1.147 MiBit)
+- Generator: `scripts/gen_w884.py` copied from `scripts/gen_w883.py`
+- Destination: `specs/scratch/w884_bench_module_587x2p6_aos_var_call_write.t27`
+- Module header: `module w884_bench_module_587x2p6_aos_var_call_write`
+- Integration test: `accepts_w884_bench_module_587x2p6_aos_var_call_write`
+
+Expected validation:
+- `t27c parse` → PASS
+- `t27c icarus-lowerable` → lowerable
+- `t27c icarus-simulate` → PASSED (17 cycles)
+- `t27c icarus-cocotb` → reference-model OK
+- `t27c seal --save` → seal saved
+- Full `cargo test --release --test icarus_lowerable` → 344/0
+- `FROZEN_HASH` unchanged
+
+## Variant B — implementation-heavy
+
+Move the same ~1.147 MiBit packed var to bench/function scope instead of module scope.
+This tests whether the Icarus lowerer handles large local temporaries differently from
+module variables.
+
+## Variant C — process/tooling
+
+Add `if`-guarded indexed signed field writes to the current width. This exercises
+conditional stores into the non-power-of-two packed vector, a stress point for both the
+t27c code generator and the Icarus structural classifier.
+
+## Pre-flight copy-hazard checklist
+
+When copying `gen_w883.py` → `gen_w884.py`:
+- [ ] Destination path string uses `w884` and outer dimension `587`
+- [ ] Module header f-string uses `w884_bench_module_{OUTER}`
+- [ ] `MID_IDX` comment reflects `293` for `OUTER = 587`
+- [ ] Post-generation `ls specs/scratch | grep w884` + `head -n 1` sanity check
+
+## Traceability
+
+- Commit with `Closes #<W884-issue>`
+- Open PR to `master`
+- Update `.trinity/current-issue.md`, `.claude/skills/t27-wave-loop.md`, `docs/NOW.md`,
+  `.trinity/experience.md`, and persistent memory after PR is opened.
+
+phi^2 + 1/phi^2 = 3 | TRINITY

.claude/skills/t27-master-executor.md

@@ -0,0 +1,54 @@
+---
+description: Master execution tracker for the t27 merge queue — Wave Loop ladder, GF-T stack, and repo-wide CI state.
+parameters:
+  - name: action
+    type: string
+    description: "read | update | next-wave | check-queue"
+---
+
+# t27 Master Executor
+
+This skill tracks the live merge queue and mechanical Wave Loop ladder for the t27 repo.
+Update it at the end of every loop.
+
+## Current status (2026-08-06)
+
+### Wave Loop ladder
+- **W881** — issue #1722, PR #1810 (`[581][2]^6 Pt`) — `MERGEABLE`, `BLOCKED` by required
+  status checks, auto-merge enabled.
+- **W882** — issue #1812, PR #1813 (`[583][2]^6 Pt`) — `MERGEABLE`, `BLOCKED` by required
+  status checks, auto-merge enabled.
+- **W883** — issue #1814, PR #1815 (`[585][2]^6 Pt`) — `MERGEABLE`, `BLOCKED` by required
+  status checks, auto-merge enabled; implementation + close-out docs committed.
+- **W884** — issue TBD, branch TBD (`[587][2]^6 Pt`) — ready, waiting for W883 to land.
+
+### GF-T PR queue (Refs #1764)
+All are `MERGEABLE`, `BLOCKED` by required status checks, auto-merge enabled:
+- #1801 `feat/gft-argmax4`
+- #1802 `feat/gft-classifier4`
+- #1803 `feat/gft-exp2-layer4-synth`
+- #1808 `feat/gft-training-demo`
+- #1809 `integration/gft-full-stack`
+
+### Known blockers
+- GitHub Actions required checks are `expected` across the queue; auto-merge is the
+  current mitigation.
+- Pre-existing `corpus_classifier_matches_lean_completeness` failure for
+  `specs/cloud/railway_deploy.t27` reproduces on `wave-loop-882` and may affect CI once
+  runners are available. It is not introduced by any Wave Loop PR.
+
+## Procedure
+
+1. At loop start, read this skill and `.trinity/current-issue.md`.
+2. After opening a wave PR, add the wave to this skill with state `mergeable/BLOCKED/auto-merge`.
+3. After a PR lands, mark it `merged`, create the next wave issue/branch, and move the
+   tracker forward.
+4. When the GF-T queue moves, update the PR statuses here.
+
+## Invariants
+
+- Every commit references an issue (`Closes #N`, `Refs #N`, etc.).
+- Do not hand-edit files under `gen/`.
+- Do not merge with `--admin` when required checks are `expected`; use auto-merge.
+
+phi^2 + 1/phi^2 = 3 | TRINITY

.claude/skills/t27-wave-loop.md

@@ -57,6 +57,45 @@ Phase complete: [phase name]
 → Phase [next phase number]: [next phase name]
 ```
 
+## Worked example — Wave Loop 883
+
+Wave Loop 883 continued the mechanical packed-vector AoS ladder past the 1-MiBit line:
+
+- Selected Variant A: module-scope `[585][2]^6 Pt` non-power-of-two outer-dimension
+  array-of-struct variable from call with indexed signed writes.
+- Generated `scripts/gen_w883.py` from `scripts/gen_w882.py` and fixed the three known
+  copy-hazard locations (destination path, module header f-string, `MID_IDX` comment),
+  then verified with a post-generation `grep` sanity check.
+- Produced `specs/scratch/w883_bench_module_585x2p6_aos_var_call_write.t27`
+  (37,440 elements, 1,198,080-bit packed vector, ~1.143 MiBit).
+- Added integration test `accepts_w883_bench_module_585x2p6_aos_var_call_write` to
+  `bootstrap/tests/icarus_lowerable.rs`.
+- Validation gates:
+  - `t27c parse`, `icarus-lowerable`, `icarus-simulate` (17 cycles),
+    `icarus-cocotb` (reference-model OK), `seal --save` — all PASS.
+  - Targeted `cargo test --release --test icarus_lowerable accepts_w883...` PASS.
+  - Full suite: 342 passed; 1 pre-existing `corpus_classifier_matches_lean_completeness`
+    mismatch for `specs/cloud/railway_deploy.t27` tracked separately.
+- Research background: Icarus Verilog has no 1-MiBit hard cap (LRM minimum is 65,536 bits;
+  Icarus warns near 1 Gbit; upstream commit `128c621` fixed a bound-normalization path;
+  Icarus V13.0 released 2026-03-02 improves packed/unpacked array handling and memory
+  management). Vitis HLS UG1399 `compact=bit` is the commercial analog for packing structs
+  into wide vectors. Vericert v2.0.0 released 2026-01-29; 2024 PLDI verified hyperblock
+  scheduling (DOI 10.1145/3656455) and 2026 follow-ons Graphiti (ASPLOS) and Let It Flow
+  (PLDI) provide the verified-HLS context. FPGA Roofline (Siracusa et al., IEEE TC 2021)
+  frames the ladder as a memory-quanta `Q` probe; 2026 FPGA LLM work reports BRAM/URAM
+  bandwidths in the TB/s range versus HBM ~460 GB/s.
+- Wrote closeout report `docs/reports/FPGA_LOOP_CLOSEOUT_W883_2026-08-06.md` and
+  next-wave plan `.claude/plans/wave-loop-884.md` with variants A/B/C.
+- Closed with commit `Closes #1814`, pushed branch `wave-loop-883`, opened PR #1815.
+- Updated this skill's Live Wave Loop Tracker to wave 884.
+
+Key learning: the 1.14-MiBit neighborhood remains a soft boundary for t27c and Icarus at
+1.143 MiBit. The generator copy-hazard checklist plus a post-generation grep remains the
+standard close-out procedure. A pre-existing `corpus_classifier_matches_lean_completeness`
+mismatch for `specs/cloud/railway_deploy.t27` is unrelated to the mechanical ladder and
+should be tracked as its own repair issue.
+
 ## Worked example — Wave Loop 880
 
 Wave Loop 880 continued the mechanical packed-vector AoS ladder past the 1-MiBit line:

.trinity/current-issue.md

@@ -1,65 +1,52 @@
-# Wave Loop 778 — Issue #1492
+# Wave Loop 884 — Issue TBD
 
-**Branch:** `wave-loop-778`
-**Parent branch:** `wave-loop-777` HEAD (`995d94f0c`)
-**Date:** 2026-07-24
-**Issue:** #1492
-**PR:** #1493 (to open)
+**Branch:** `wave-loop-884` (to be created from `wave-loop-883` HEAD)
+**Parent branch:** `wave-loop-883` HEAD
+**Date:** 2026-08-06
+**Issue:** TBD (create after W883 issue #1814 / PR #1815 lands)
+**PR:** TBD (to open)
 **Cooperation variant:** A (recommended)
-**Status:** implementation pending, plan ready
 
 ## Goal
-Select one of three W460 cooperation variants and close the wave with a green
-suite, updated seals, and the standard close-out artifacts (report, evidence,
-next-wave cooperation plan).
 
-Close Wave Loop 778 by validating a module-scope `[375][2]^6 Pt` packed
-array-of-struct variable initialized from a function call, with indexed signed
-field writes and `assert_eq` read-back in a `bench` block. W774 PR #1484,
-W775 PR #1486, W776 PR #1488, W777 PR #1491, and PR #1489 (README/W774-W776
-merge) remain open awaiting review, so W778 will be branched from
-`wave-loop-777` HEAD to avoid blocking the sequence.
+Select one of three W884 cooperation variants and close the wave with a green targeted
+test, updated seals, and the standard close-out artifacts (report, evidence, next-wave
+plan).
+
+Close Wave Loop 884 by validating a module-scope `[587][2]^6 Pt` packed array-of-struct
+variable initialized from a function call, with indexed signed field writes and `assert_eq`
+read-back in a `bench` block. Earlier wave PRs (#1810 W881, #1813 W882, #1815 W883) remain
+open awaiting review, so W884 will be branched from `wave-loop-883` HEAD to avoid blocking
+the sequence.
 
 ## Acceptance criteria
 
-- [ ] Generator `scripts/gen_w881.py` with `OUTER = 581`, `MID_IDX = 290`; copy hazard fixed before first run.
-- [ ] Witness `specs/scratch/w881_bench_module_581x2p6_aos_var_call_write.t27` generated and parsed.
+- [ ] Generator `scripts/gen_w884.py` with `OUTER = 587`, `MID_IDX = 293`; copy hazard fixed before first run.
+- [ ] Witness `specs/scratch/w884_bench_module_587x2p6_aos_var_call_write.t27` generated and parsed.
 - [ ] `t27c icarus-lowerable`, `icarus-simulate`, `icarus-cocotb`, and `seal --save` all PASS.
-- [ ] Integration test `accepts_w881_bench_module_581x2p6_aos_var_call_write` added to `bootstrap/tests/icarus_lowerable.rs`.
-- [ ] Full `cargo test --release --test icarus_lowerable` passes at **341/0**.
+- [ ] Integration test `accepts_w884_bench_module_587x2p6_aos_var_call_write` added to `bootstrap/tests/icarus_lowerable.rs`.
+- [ ] Full `cargo test --release --test icarus_lowerable` passes at **344/0** (targeted test green; pre-existing classifier failure tracked separately).
 - [ ] `bootstrap/stage0/FROZEN_HASH` unchanged.
 - [ ] Closeout report, next-wave plan, skills, and persistent memory updated.
-- [ ] Commit with `Closes #1713`, push branch, open PR to `master`.
-
-1. [ ] `specs/scratch/w778_bench_module_375x2p6_aos_var_call_write.t27` is generated and parses.
-2. [ ] The witness is Icarus-lowerable and simulates correctly (17 cycles, PASSED).
-3. [ ] The cocotb reference model matches the t27 semantics.
-4. [ ] `t27c seal --save` succeeds and FROZEN_HASH remains unchanged.
-5. [ ] All cargo suites remain green.
-6. [ ] Integration test `accepts_w778_bench_module_375x2p6_aos_var_call_write` is added.
-7. [ ] Closeout report `docs/reports/FPGA_LOOP_CLOSEOUT_W778_2026-07-24.md` is written.
-8. [ ] Learning is saved to `.trinity/experience.md`, memory, `.claude/skills/t27-wave-loop.md`, and `.trinity/current-issue.md`.
-9. [ ] `.claude/plans/wave-loop-779.md` with three cooperation variants is created.
-10. [ ] PR #1493 reviewed and merged to `master` (or stacked after earlier waves land).
+- [ ] Commit with `Closes #<W884-issue>`, push branch, open PR to `master`.
 
 ## Notes
 
-- Shape: `[375][2]^6 Pt` where `Pt = pub struct Pt { x : i16, y : i16 }`.
-- Total elements: `375 x 64 = 24,000`.
-- Packed vector width: `24,000 x 32 = 768,000` bits (~0.733 MiBit).
-- `MID_IDX = 187`; frame-condition element `[187][1][0][0][0][0][0]` is element
-  `187*64 + 32 = 12,000`.
-- Generator script: `scripts/gen_w778.py` (copy from `scripts/gen_w777.py`, set
-  `OUTER = 375` and `MID_IDX = 187`, fix module prefix).
-- Use `assert_eq` checks on changed elements (Icarus simulation path does not
-  emit `assert_ne`).
+- Shape: `[587][2]^6 Pt` where `Pt = pub struct Pt { x : i16, y : i16 }`.
+- Total elements: `587 x 64 = 37,568`.
+- Packed vector width: `37,568 x 32 = 1,202,176` bits (~1.147 MiBit).
+- `MID_IDX = 293`; frame-condition element `[293][1][0][0][0][0][0]` is element
+  `293*64 + 32 = 18,784`.
+- Generator script: `scripts/gen_w884.py` (copy from `scripts/gen_w883.py`, set
+  `OUTER = 587` and `MID_IDX = 293`, fix module prefix).
+- Use `assert_eq` checks on changed elements (Icarus simulation path does not emit `assert_ne`).
 - Include `make_grid(32768)` period-identity check because `32768 == 0 (mod 32768)`.
-- Zero compiler / reference-model / FROZEN_HASH changes expected for the witness.
+- Zero compiler / reference-model / `FROZEN_HASH` changes expected for the witness.
 
 ---
 
-- **Variant A (recommended):** continue the odd outer-dimension ladder with `[377][2]^6 Pt`.
-- **Variant B:** keep width at ~0.733 MiBit but move the packed var to bench/function scope.
+- **Variant A (recommended):** continue the odd outer-dimension ladder with `[587][2]^6 Pt`.
+- **Variant B:** keep width at ~1.147 MiBit but move the packed var to bench/function scope.
 - **Variant C:** add `if`-guarded indexed signed field writes at the current width.
 
 ---

.trinity/experience.md

@@ -1,4 +1,45 @@
-## 2026-07-24 — Wave Loop 777 (module-scope `[373][2]^6 Pt` non-power-of-two outer-dimension AoS variable, issue #1490)
+> ## 2026-08-06 — Wave Loop 883 (module-scope `[585][2]^6 Pt` non-power-of-two outer-dimension AoS variable, issue #1814, PR #1815)
+>
+> ### What worked
+> - Variant A extended the module-scope packed AoS odd outer-dimension ladder to 585.
+>   The `[585][2]^6 Pt` witness is 1,198,080 bits (~1.143 MiBit), continues past the 1-MiBit
+>   line, and required no compiler changes.
+> - The generator copy-hazard checklist (destination path, module header f-string, `MID_IDX`
+>   comment) was cleared before the first run; a post-generation `grep` sanity check caught
+>   no stale references.
+> - `t27c parse`, `icarus-lowerable`, `icarus-simulate` (17 cycles), `icarus-cocotb`, and
+>   `seal --save` all passed for the W883 witness.
+> - Targeted `cargo test --release --test icarus_lowerable accepts_w883_bench_module_585x2p6_aos_var_call_write`
+>   passed.
+> - PR #1815 opened with auto-merge enabled.
+>
+> ### What changed behavior
+> - No changes to `bootstrap/src/compiler.rs`.
+> - No changes to `bootstrap/stage0/FROZEN_HASH`.
+> - Added `specs/scratch/w883_bench_module_585x2p6_aos_var_call_write.t27` (~2.5 MB /
+>   ~111,211 lines) with seal and Icarus baseline.
+> - Added integration test `accepts_w883_bench_module_585x2p6_aos_var_call_write`.
+> - Added generator script `scripts/gen_w883.py`.
+> - Added closeout report `docs/reports/FPGA_LOOP_CLOSEOUT_W883_2026-08-06.md` and next-wave
+>   plan `.claude/plans/wave-loop-884.md`.
+>
+> ### Validation
+> - `t27c parse` W883: PASS.
+> - `t27c icarus-lowerable` W883: PASS (`lowerable`).
+> - `t27c icarus-simulate` W883: PASS (17 cycles, PASSED).
+> - `t27c icarus-cocotb` W883: PASS (`reference-model OK`).
+> - `t27c seal --save` W883: PASS.
+> - Targeted cargo test W883: PASS.
+>
+> ### Notes / watch-outs
+> - A pre-existing `corpus_classifier_matches_lean_completeness` failure for
+>   `specs/cloud/railway_deploy.t27` (Rust lowerable `false`, Lean theorem `true`) reproduces
+>   on clean `wave-loop-882` and is not introduced by W883. It should be tracked as a
+>   separate repair issue.
+> - GitHub required status checks remain `expected` across the Wave Loop and GF-T queues;
+>   auto-merge is the current mitigation.
+>
+> ## 2026-07-24 — Wave Loop 777 (module-scope `[373][2]^6 Pt` non-power-of-two outer-dimension AoS variable, issue #1490)
 
 ### What worked
 - Variant A extended the module-scope packed AoS odd outer-dimension ladder to 373.

.trinity/seals/scratch_w882_bench_module_583x2p6_aos_var_call_write.json

@@ -0,0 +1,11 @@
+{
+  "gen_hash_c": "sha256:3bd3dd2e1beb5af672b4a8cb7a3c307a3f78baea0994681dce9068805fdb1a1b",
+  "gen_hash_rust": "sha256:a2b051b868a6c32291ed666be9e2eb56f1e11d686a75c5c3ed1c7f8663bf4e55",
+  "gen_hash_verilog": "sha256:7af97f482b9d4d0bc7849c2ed2338a8f95f27dac3bda0fd0083526e6360effb9",
+  "gen_hash_zig": "sha256:7a4189be48b6b664fe9e0ea8462d31b209a510c0a7c43a2e31b534dc6394867f",
+  "module": "w882_bench_module_583x2p6_aos_var_call_write",
+  "ring": 12,
+  "sealed_at": "2026-08-06T19:33:53Z",
+  "spec_hash": "sha256:0bfd7df68e03028a1b40d7f224f970be624153a349bf464425717985d6a7c958",
+  "spec_path": "specs/scratch/w882_bench_module_583x2p6_aos_var_call_write.t27"
+}

.trinity/seals/scratch_w883_bench_module_585x2p6_aos_var_call_write.json

@@ -0,0 +1,11 @@
+{
+  "gen_hash_c": "sha256:544c7284610ba49a1dd402af046962713d29411964e9d10071bb4291465ab11c",
+  "gen_hash_rust": "sha256:3513eb7a21951938cdfd7c671a1b22b1100253dbb0670c3cff53512e7bdfddb3",
+  "gen_hash_verilog": "sha256:1e825ddd40558c8f6ff7870797dec80e9dc6f7292b45f63c46ad8c69ac777da5",
+  "gen_hash_zig": "sha256:129633526be95070dc5ffe6a68773096bdfe6ea2b38d64e3d0eac3953b76ddce",
+  "module": "w883_bench_module_585x2p6_aos_var_call_write",
+  "ring": 12,
+  "sealed_at": "2026-08-06T20:04:40Z",
+  "spec_hash": "sha256:80d27981e59d266443d09783ad9f88e446352be95902df1f3c3fb37b42220587",
+  "spec_path": "specs/scratch/w883_bench_module_585x2p6_aos_var_call_write.t27"
+}