gHashTag · gHashTag · Aug 21, 2026 · Aug 21, 2026
@@ -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
@@ -558,6 +558,45 @@ standard close-out procedure. When the upstream `master` GF-T stack moves concur
 rebuilding the wave branch from `master` with only the implementation commits (and
 re-applying close-out docs) resolves merge conflicts while preserving the PR.
 
+## 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:

@@ -574,6 +574,47 @@
 >   branch from `master` with only the wave implementation commits and re-apply the
 >   close-out docs.
 >
+> ## 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

@@ -0,0 +1,11 @@
+# NOW -- the Wave Loop 883 record lands, ten sibling PRs close (2026-08-21)
+
+## docs(igla): land Wave Loop 883 close-out record (Refs #1814)
+
+- Rebuilt PR #1815 on top of `master` (`10e3d5e`): **5 files, +244/-0**, down from the 15 files it showed against a merge base 848 commits old. Every dropped file was content `master` already carried, or scratch material that is now gitignored
+- **Recovers three files that exist nowhere on `master`**: `.claude/plans/wave-loop-884.md`, `docs/reports/FPGA_LOOP_CLOSEOUT_W883_2026-08-06.md`, `docs/reports/FPGA_LOOP_COOPERATION_W884_2026-08-06.md`. `master` holds plans `wave-loop-880`, `881`, `885`..`899` but not `882`..`884`, and closeouts `W880`, `W884`..`W889` but not `W881`..`W883`. This closes the W883/W884 half of that gap; the W881/W882 half was never written by any PR and stays open
+- `.trinity/experience.md`: the W883 entry is inserted between W884 and W777, where the log jumped from 2026-08-06 straight back to 2026-07-24
+- `.claude/skills/t27-wave-loop.md`: the "Worked example -- Wave Loop 883" section is inserted between the W884 and W880 examples
+- **Dropped deliberately**: `specs/scratch/w883_*.t27` and `.trinity/seals/scratch_w88{2,3}_*.json` -- gitignored since #2283, and a scratch seal is exactly the `phantom` class `check_seal_coverage.py` says to resolve by dropping the seal; `docs/NOW.md` -- frozen archive since #2298, this entry is the replacement for that hunk (which was also written in Russian); `scripts/gen_w882.py`, `scripts/gen_w883.py` and the `bootstrap/tests/icarus_lowerable.rs` hunk -- already on `master`, byte-identical; and the live-status pointers superseded by wave 898
+- **Ten sibling PRs closed rather than merged**: #1810, #1813, #1842, #1844, #1847, #1850, #1852, #1854, #1856, #1858. Measured against `master` each had zero durable unique content -- their `.claude/plans/`, `docs/reports/FPGA_LOOP_CLOSEOUT_W*`, `scripts/gen_w*.py` are all SAME-BLOB with `master` (the W890..W898 record landed via #1900, `e756e8c`), and `master` already carries all 352 `accepts_w*` tests including `accepts_w881`..`accepts_w898`. What remained was ten `specs/scratch/` witnesses and ten phantom seals
+- **No test was deleted.** The `accepts_w*` tests that assert `p.exists()` on gitignored `specs/scratch/` witnesses are left exactly as they are on `master`; that defect is repo-wide, pre-existing, and recorded in `docs/now/2026-08-21-wave-loop-898.md`. The ten closed branches are left in place, so their scratch witnesses stay reachable
@@ -0,0 +1,59 @@
+# Wave Loop 883 Close-Out Report
+
+**Date:** 2026-08-06
+**Issue:** #1814
+**Branch:** `wave-loop-883`
+**Parent branch:** `wave-loop-882` HEAD (`85e2db7c`)
+**PR:** #1815 (to `master`)
+**Cooperation variant:** A (recommended)
+
+## What was done
+
+Wave Loop 883 continued the mechanical packed-vector array-of-struct ladder past the
+1-MiBit line with the recommended Variant A:
+
+- Module-scope `[585][2]^6 Pt` non-power-of-two outer-dimension array-of-struct variable
+  initialized from a function call, with indexed signed field writes and `assert_eq`
+  read-back in a `bench` block.
+- Generator `scripts/gen_w883.py` copied from `scripts/gen_w882.py` and updated:
+  `OUTER = 585`, `MID_IDX = 292`, destination path, module header, and `MID_IDX` comment.
+- 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`.
+- Sealed witness: `.trinity/seals/scratch_w883_bench_module_585x2p6_aos_var_call_write.json`
+  (`sha256:80d27981...`).
+
+## Validation matrix
+
+| Gate | Result |
+|------|--------|
+| `t27c parse` | PASS |
+| `t27c icarus-lowerable` | lowerable |
+| `t27c icarus-simulate` | PASSED (17 cycles) |
+| `t27c icarus-cocotb` | reference-model OK |
+| `t27c seal --save` | saved |
+| Targeted cargo test `accepts_w883...` | PASS |
+| Full `cargo test --release --test icarus_lowerable` | 342 passed; 1 pre-existing failure¹ |
+| `bootstrap/stage0/FROZEN_HASH` | unchanged |
+
+¹ The pre-existing `corpus_classifier_matches_lean_completeness` mismatch 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 is being tracked separately.
+
+## Process notes
+
+- PR #1815 was opened with auto-merge enabled. GitHub required status checks are currently
+  `expected`, so merge is blocked pending Actions runner availability — the same pattern as
+  W881 (#1810) and W882 (#1813).
+- The wave branch was created from `wave-loop-882` HEAD because earlier wave PRs remain open.
+- The generator copy-hazard checklist was cleared before the first run; no stale references
+  required a second pass.
+
+## Next wave
+
+- Wave Loop 884: module-scope `[587][2]^6 Pt` (Variant A).
+- Plan: `.claude/plans/wave-loop-884.md`.
+- Cooperation variants: `docs/reports/FPGA_LOOP_COOPERATION_W884_2026-08-06.md`.
+
+phi^2 + 1/phi^2 = 3 | TRINITY
@@ -0,0 +1,40 @@
+# Wave Loop 884 Cooperation Variants
+
+**Date:** 2026-08-06
+**Issue:** TBD (to be created after W883 lands)
+**Context:** Wave Loop 883 successfully validated `[585][2]^6 Pt` (~1.143 MiBit). The mechanical
+ladder remains healthy; the next step is to keep probing width growth while preserving the
+zero-compiler-change invariant.
+
+## Variant A — Recommended: continue the module-scope odd outer-dimension ladder
+
+Validate a module-scope `[587][2]^6 Pt` non-power-of-two outer-dimension array-of-struct
+variable from a function 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)
+- Smallest, most predictable increment. Keeps generator/test/code footprint identical to
+  prior waves and gives another clean data point on the width-vs-lowerability curve.
+
+## Variant B — Implementation-heavy: move the packed var to bench/function scope
+
+Keep the same ~1.147 MiBit width (`[585][2]^6 Pt` or push to `[587][2]^6 Pt`) but place the
+variable inside a `bench` or function scope rather than at module scope. This tests whether
+the Icarus lowerer handles large local packed temporaries differently from module-level
+state.
+
+## Variant C — Process/tooling: add `if`-guarded indexed signed field writes
+
+At the current width (`[585][2]^6 Pt` or `[587][2]^6 Pt`), replace unconditional signed writes
+with conditional writes (`if (cond) dst[i].x = ...`). This exercises control-flow interaction
+with the non-power-of-two packed-vector store path, a stress point for both t27c code
+generation and the Icarus structural classifier.
+
+## Recommendation
+
+Select **Variant A** for Wave Loop 884. It preserves the mechanical ladder, requires zero
+compiler changes, and adds another 4,096-bit step past the 1-MiBit line before considering
+scope or control-flow variants.
+
+phi^2 + 1/phi^2 = 3 | TRINITY