feat: memory runtime, fixed collections & low-level stdlib primitives

[BlobMaster41]

Dep upgrades, memory runtime, fixed collections & low-level stdlib primitives

This branch builds on top of v0.29 with four things: bumped dev deps, a new GC-free memory runtime, fixed-capacity collections, and a set of zero-overhead low-level primitives for the standard library.

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Dev dependency upgrades

Bumped all the dev tooling to current versions and regenerated every .wat test fixture to match the new output.

Package	Old	New
@eslint/js	(new)	^10.0.1
eslint	^8.x	^10.0.3
@typescript-eslint/*	^5.62.0	^8.56.1
@types/node	^18.x	^25.3.5
esbuild	^0.25.0	^0.27.3
typescript-eslint	(new)	^8.56.1
globals	(new)	^17.4.0

Also tweaked .eslintrc.cjs and eslint.config.js to work with the new ESLint, and fixed 4 lint issues in the UMD bundles (indentation in lib/loader/umd/index.js, unused vars in both loader and rtrace UMD files).

Renamed the loader package from @assemblyscript/loader to @btc-vision/as-loader and updated the rtrace package metadata to match.

The .wat fixture regeneration accounts for the bulk of the diff (~300 files, ~400k lines changed). The actual code changes are about +1,800 lines.

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Memory runtime (--runtime memory)

A new runtime option that gives you allocation without any garbage collector. Designed for blockchain contracts and embedded use cases where you want predictable memory behavior and zero GC overhead.

New files:

• std/assembly/rt/memory-runtime.ts — bump allocator with alignment, auto memory.grow, no-op __free/__link/__visit
• std/assembly/rt/index-memory.ts — entry point
• std/assembly/shared/runtime.ts — added Runtime.Memory = 3

Compiler changes (src/compiler.ts, src/program.ts, src/passes/shadowstack.ts):

• CLI accepts --runtime memory
• Skips exporting runtime functions in this mode
• Safer instance lookups
• Shadow stack uses unreachable() when exception handling is on
• Default stackSize: 65536 in asconfig.json

Stdlib conditional GC — seven modules now skip __link and __visit calls when ASC_RUNTIME == Runtime.Memory:

• array.ts, map.ts, set.ts, staticarray.ts, typedarray.ts, string.ts, function.ts

Also changed the abort feature check in builtins.ts to use the ASC_FEATURE_EXCEPTION_HANDLING flag directly.

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Fixed collections

Pre-allocated, fixed-capacity data structures. No dynamic growth, no GC pressure. They use __alloc under the memory runtime and __new otherwise.

FixedArray<T> (std/assembly/fixedarray.ts)

Contiguous buffer, manual length tracking. push/pop/swapDelete/indexOf/includes/fill/clear. Bounds-checked [], unchecked {}.

FixedMap<K,V> (std/assembly/fixedmap.ts)

Open-addressing hash map with linear probing and fixed bucket count. has/get/set/delete/clear/keys/values.

FixedSet<T> (std/assembly/fixedset.ts)

Same probing strategy as FixedMap. has/add/delete/clear/values.

All three have proper __visit implementations that only traverse managed elements when GC is active. Added E_CAPACITYEXCEEDED error constant.

Tests: tests/compiler/std/fixedarray.ts, fixedmap.ts, fixedset.ts with full fixture files.

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Low-level primitives

Five new stdlib modules. All zero-overhead — inline functions and unmanaged types, no allocations, no GC.

Pointer<T> (std/assembly/pointer.ts)

Promoted from the old experiment in tests/compiler/std/pointer.ts. An @final @unmanaged class that IS a usize via changetype. Supports arithmetic (+, -, ++, --), indexing ([]), dereferencing (.value), plus new methods: isNull(), equals(), copyTo(), Pointer.null<T>().

Endian (std/assembly/endian.ts)

Inline wrappers for endian-aware memory access. loadBE/storeBE do bswap(load(...)), loadLE/storeLE are identity since wasm is LE. toBE/fromBE/toLE/fromLE for value conversion.

ByteSlice (std/assembly/byteslice.ts)

A (ptr, length) pair with bounds-checked, endian-aware reads and writes. Like DataView but doesn't own an ArrayBuffer — it views raw memory. Big-endian by default (matches protocol conventions). Constructor validates length >= 0, copyTo guards against negative count. Has getU8/16/32/64, signed variants, slice(), copyTo(), fill(), equals(), toPointer<T>().

BitFlags (std/assembly/bitflags.ts)

Inline generic functions for bit manipulation: has, hasAny, test, set, clear, toggle, popcount, isEmpty. Each compiles to 1-2 wasm instructions. Constrained to integer types via <T extends number> + compile-time isInteger<T>() guard — using BitFlags.has<f32>(...) gives you a clear error.

Encoding (std/assembly/encoding.ts)

Hex and varint codecs:

• Hex: encode/decode (multi-byte), encodeByte/decodeByte (single), handles both upper and lowercase input
• LEB128: encodeU32/decodeU32/encodeU64/decodeU64 with max byte guards (5 for u32, 10 for u64) to prevent infinite loops on malformed data
• Bitcoin CompactSize: encodeCompact/decodeCompact, little-endian payloads per spec

All type declarations added to std/assembly/index.d.ts with JSDoc. Pointer gets operator overload declarations, ByteSlice documents be parameter defaulting to true.

Tests for all five in tests/compiler/std/ with debug + release WAT fixtures.

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Other changes

• Updated test.yml workflow
• Loader/rtrace package.json metadata updates
• lib/loader and lib/rtrace UMD bundles regenerated
• rt.ts minor annotation cleanup

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Numbers

What	Count
Files changed	363
Actual source changes	+1,789 / -102 (26 files)
Test fixtures regenerated	~320 .wat files
New stdlib modules	8
New compiler/runtime files	3

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Testing

• npm run build passes
• All new tests pass — pointer, endian, bitflags, byteslice, encoding, fixedarray, fixedmap, fixedset (debug + release compile, fixture match, wasm instantiation)
• No regressions on existing stdlib tests (array, map, set, string)
• Lint clean (eslint --max-warnings 0)
• BitFlags correctly rejects float types at compile time
• Full npm test suite
• Memory runtime integration with --runtime memory