Phase 2, S35. Two real defects from one root cause, both confirmed by trace
rather than taken from the audit:
1. Divergence. WasmIML built its TS Dataset mirror with a cap of 100 while
every addExample() ALSO pushed into the C++ FIFO ring, capped at 128. Since
train() reads the C++ ring and trainAsync() reads the TS mirror, past 100
examples the two trained on different datasets — silently.
2. Latent OOB read. nisps_ml_train sizes its sample-weight span by the C++
side's example_count() (up to 128), but wasm-iml.ts allocates that heap
buffer from the TS dataset's size (<=100). Once the ring exceeds the mirror,
the span reads past the end of the caller's allocation.
Fix: name the capacity ONCE as nisps::ml::kDefaultMaxExamples = 128, used by
FixedStorage's default template arg, DynamicStorage's default ctor arg, and the
MLP<> alias (which is the only real FixedStorage instantiation path and carried
its own independent 128 literal — the last copy of this dual truth). Expose it
through nisps_ml_describe and have the TS side read it instead of hardcoding.
Dataset's constructor default is removed entirely: a default was what invited
this bug class, and the sole call site now always supplies the describe() value.
ABI NOTE: this extends nisps_ml_describe from a 6-int to a 7-int descriptor.
nisps_ml_describe always writes 7 ints regardless of the caller's buffer, so
every call site had to grow in the same change or it would overflow the WASM
heap by 4 bytes per call. All five sites updated: three in wasm-iml.ts (init
defaults, init per-instance, reshape re-describe — the finding said there were
two), one in wasm-worker.ts, one in tests/cpp/parity_wasm.mjs. The parity
harness's expected-dims check now also pins the new max_examples slot.
Regression test: tests/cpp/test_mlp_storage_defaults.cpp — pins the two storage
policies to one constant, and drives MLPCore<DynamicStorage> exactly as
bindings.cpp does past the old TS cap, asserting it saturates at 128 and not at
100. Fail-before/pass-after confirmed by temporarily setting the constant to
100: 2 failures, named. Reverted: green.
Audit correction: the cited dataset.ts:81 is the FIFO eviction check; the
hardcoded default was at dataset.ts:45.
Gates: run-all-tests.sh ALL GREEN, parity PASS.
Phase 1 group 2 (L27, L26, L28, S21, L13, ST6, S20).
- L27: fixed_buffer.hpp + its test + the CMake entry — no consumers.
- L26: dislike_multiplier_ and its doubling/halving bookkeeping — upstream
InterfaceRL residue that drove nothing. The audit pointed at the wrong test
file for the surviving reference; the actual assert was in
test_mlp_geo_dislike.cpp:211, removed here.
- L28: added copy_weights_to(std::span<float>) to FixedStorage and
DynamicStorage and switched feedback.hpp's take_snapshot/push_undo/nudge to
it. Drops the permanent whole-net flat_ scratch buffer from FixedStorage and
the per-gesture double copy. Behaviour-identical: same source values, same
write order, same RNG draw order in nudge().
- S21 + L13: deleted NISPS_AUDIO_MEM / NISPS_APP_SRAM / NISPS_AUDIO_FUNC —
zero use sites outside perf.hpp and comments — and rewrote midi_io.hpp's one
misshapen NISPS_AUDIO_FUNC use as a plain `inline void`. perf.hpp now
documents only the inlining/hotness macros that actually exist, and
audio_driver.hpp no longer claims an SRAM discipline the code never had.
- ST6: feedback.hpp's header now describes the four current modes and the
Geometric default, dropping the retracted "geometric push NOT ported" claim.
S20 — OPERATOR DECISION (§7.1): the four legacy feedback behaviours
(RandomiseOutputs, RandomiseMlp, AvoidStyle::Diffuse, the RandomiseMlp branch of
on_drag) are KEPT, not deleted. They are wanted as building blocks for
experimenting with how different instruments feel under different behaviours.
Each is now marked at its definition as deliberately-retained research reserve
so future audits stop flagging it as dead code.
L25 (the 16 KB firmware loss-history buffer) is NOT done here — see the phase
report; it turned out to be coupled into the shared mlp.hpp, and its fate
belongs with the browser telemetry build (§7.3 / plan §6.5e).
Gates: run-all-tests.sh ALL GREEN.
Replace the vendored runtime MLP in vcv/src/iml.hpp (DetRng + 3D-weight-store
MLP + Dataset + IML) with a THIN, Rack-free adapter over the shared core:
nisps::ml::MLPCore<nisps::ml::DynamicStorage> (8->[16,24,16]->16, the P2 dynamic
case), nisps::Rng, and the core MLP's own FIFO dataset. Behaviour changes from
the vendored approximation to core-exact firmware/WASM semantics.
- MEMLNaut.cpp: staged/pending weight buffers and patch JSON now use the core's
flat [weights..][biases..] vector (nisps::IML<float>::Weights); patch version
bumped to 3. Double-buffer / single-writer threading discipline unchanged.
- New ctest tests/cpp/test_vcv_iml_parity.cpp: seeded train/infer/move_weights
session through the adapter is memcmp-equal to a bare MLPCore<DynamicStorage>.
- Docs: vcv-module.md delta #5 marked CLOSED (2026-07-18); MAP.md vcv/ updated.
Closes vcv-module.md delta #5.
Algorithms (forward, backprop/SGD, init, move_weights, diagnostics) now live
once in MLPCore<Storage> (nisps/ml/mlp.hpp). Storage models:
- FixedStorage (storage.hpp): template-sized std::array, zero heap. The
classic MLP<NIn,H1,H2,H3,NOut,...> is an alias preserving kInput/kHidden*/
kOutput/kNumLayers/weight_count() constexpr — firmware + bindings + modes
compile unchanged.
- DynamicStorage (dynamic_storage.hpp): runtime dims, ONE arena allocation
at construction, nothing per-call. #error under NISPS_TARGET_EMBEDDED
(new macro in core/perf.hpp); sole lint-cpp.sh heap-allowlist entry, plus
a lint check that fails if the #error guard disappears.
Verification:
- new ctest test_mlp_storage_parity: fixed↔dynamic BIT-identical across
init/draw/inference/train(FIFO)/move_weights(pin mask)/eval_loss/
layer_stats/set_weights/infer_batch/reset; invalid+moved-from inert
- golden ML vectors (pre-refactor constants) pass → bit-stable refactor
- native↔WASM parity PASS, max delta unchanged (2.4e-7)
- chokepoint B compile: PAFSynth .text 122324→122692 (+0.30%, ±1% budget);
RAM +416B (eval scratch)
- fix: firmware-common.sh used bare 'python' (absent here) → ${PYTHON:-python3}
Part of one-core-engine-refactor P2. nisps_ml_create ABI untouched (P2.2 is
an operator stop-point).
New SLP-Workshop firmware variant (Synth Library Portland), built on the
MEMLCelium engine + MLP shape. Ports the two post-fork learning-algorithm
changes from upstream memllib InterfaceRL into the shared nisps/ml core,
runtime-configurable (no compile-time switch), inert by default:
- nisps/ml/jolt.hpp: Jolt — held continuous weight morph over the flat
weight buffer + post-release LR ramp (kJolt* constants verbatim).
- nisps/ml/ou_noise.hpp: OUNoise<N> — Ornstein-Uhlenbeck exploration walk
on the output vector (theta=0.02, dt=0.001, kMaxAmplitude=0.65).
Both wired into ModeBase so every mode gains jolt_press/jolt_release/
jolt_lr_scale + set_explore_intensity; gated so existing modes stay
bit-identical (parity + golden tests green). Firmware surfaces them on
TogB1 (Jolt) and RVX1 (explore). New SLPWorkshopMode mode + schema +
codegen; firmware alias + .ino variant; playground mode registration.
Tests: jolt + OU unit tests, ModeBase learning integration incl. an
inert-parity test proving SLP-Workshop == MEMLCelium with features off.
Verified: cpp tests, wasm build, native↔wasm parity, lint, codegen
golden, playground typecheck. Firmware compile/e2e/hardware are
environment-bound (no arduino-cli/submodules/browser here).
Refs ergo 019f0fca.
Wire the modular input layer into the Console and reshape the browser
engine so input axes are genuine independent dimensions.
Inputs (manifold/src/inputs/):
- gamepad-source: emit press+release edges with standard-mapping labels
(enables hold-and-move); single/double-stick already present.
- midi-input-source: single-device selection + batch "MIDI Learn"
(every CC swept while armed becomes an axis); notes stay discrete.
- input-layer: compose() forwards each axis 1:1 (no mean-blend);
add onReducedInput so the manifold tracks gamepad/MIDI position.
- types: InputAction.phase, InputMode.
Console (manifold/src/console/):
- ConsoleApp: bind gamepad buttons to verdicts (RB up / LB down /
X randomise / Y nudge / B undo / A-hold reposition); mirror composed
position onto the manifold.
- Drawers: rebuilt Inputs drawer (source picker, gamepad legend, MIDI
device picker + batch-learn flow, learned-control meters).
Engine (nisps/wasm, manifold/src/engine):
- DefaultMLP widened MLP<2,..> -> MLP<32,..> (32 = MAX_AXES); each
active axis gets a dedicated slot, unused slots held at 0 (inert).
Rebuilt nisps.wasm (playground + manifold).
- spine/engine-api: setInputs writes the full N-D vector (was dropping
arr[2+]); primary pair keeps the 2-D pipeline; process() re-ticks the
whole vector via spine.reprocess().
Tests:
- parity_check/parity_wasm: ParityMLP -> 32 inputs, widen example bufs.
- CMakeLists: build parity binary with -ffp-contract=off so native
matches FMA-free WASM (training amplified the gap past 1e-5).
Inputs dock is still an exclusive picker; mixing toggles, reshape modal,
and the >2-D slider view (inputs-spec.md) are groundwork-laid but not
yet wired. See docs/redesign/midi-gamepad-inputs-worklog.md.
CMakeLists.txt:
- Native host build by default; Emscripten-target detection plumbed but
WASM emit deferred to stream 7 (playground build script).
- Header-only INTERFACE library `nisps_core`.
- Host test executable `nisps_core_tests` compiled with -Wall -Wextra
-Werror -Wpedantic (Chris's rules: clean build is non-negotiable).
tests/cpp/test_helpers.hpp:
- Minimal NISPS_TEST / NISPS_EXPECT / NISPS_EXPECT_NEAR macros, no external
deps. Rationale documented in-file: Catch2/doctest would add ~10MB and 30s
for what is currently <100 LOC of test runtime.
22 unit tests covering FixedBuffer (5), RingBuffer (5), Rng (7), math (5).
All green; verified via `cmake --build nisps/build && ./nisps/build/nisps_core_tests`.
