BEAM-native JS engine and compiler by dannote · Pull Request #5 · elixir-volt/quickbeam

dannote · 2026-04-15T10:37:55Z

Adds a second QuickJS execution backend that runs decoded QuickJS bytecode on the BEAM, plus an experimental compiler path that lowers QuickJS bytecode to BEAM modules.

Public API and runtime modes

mode: :beam support for running JavaScript through the BEAM VM backend
mode: :auto compiler-backed execution with fallback
strict compiler audit mode via mode: :beam_compiler
QUICKBEAM_MODE=beam_compiler support for audit runs
raw BEAM disassembly for the :beam backend via QuickBEAM.disasm/2
runtime/context integration, handler dispatch, module loading, dynamic import, globals, and interop for the VM path
stack traces, source positions, and Error.captureStackTrace

Bytecode VM

QuickJS bytecode decoder in Elixir
BEAM interpreter for QuickJS bytecode
control-flow, stack-depth, type, and diagnostics analysis passes
local/argument/capture slot handling, including large-frame tuple mode
generator and async-generator execution support
promise scheduling and continuation state
runtime invocation helpers for compiled and interpreted functions

Compiler backend

hybrid compiler from QuickJS bytecode to BEAM modules
block lowering, CFG analysis, stack-depth inference, type inference, and optimizer passes
compiled runtime helpers for arithmetic, coercion, calls, construction, refs, globals, with-scope, iterators, objects, classes, promises, generators, and errors
strict compiler-vs-interpreter audit harnesses and semantic corpus benches
compiler opcode coverage reporting
compiler perf/ROI benchmark

JavaScript semantics covered

Object, Array, Function, String, Number, Boolean
Math, JSON, Date, RegExp
Map, Set, WeakMap, WeakSet, collection iterators, and self-iterability
Symbol, well-known symbols, property keys, and Symbol.toStringTag
Promise, async / await, generators, delegated yield*, and async generators
Proxy and Reflect, including descriptor/prototype/extensibility invariants
TypedArray, ArrayBuffer, BigInt
classes, inheritance, super, private fields, private methods, private accessors, static private members, brand checks, and constructor return semantics
descriptors, Object.create, Object.assign, Object.fromEntries, freeze/seal/preventExtensions/isExtensible/isFrozen/isSealed
array expando properties, sparse arrays, callbacks, iterators, destructuring, spread, rest/default parameters, and arguments basics
eval, with, refs, globals, callback/global write freshness, delete semantics, in, instanceof, new, update operators, arithmetic/coercion edge cases, and BigInt operations
try/catch/finally, QuickJS gosub/ret finally control flow, nested catches inside finally, break/continue through finally, and catch-region slot preservation
for-in enumeration mutation and nullish object coercion for with/destructuring
Web API and Node-compat runtime integration used by the VM path

Static analysis and cleanup

updated ex_dna, ex_slop, and credo
mix lint now runs ExDNA with a zero-clone budget
clone debt removed across VM runtime helpers, parser helpers, Web API modules, and collection/object helpers
Bandit clock application startup fixed for --no-start test runs
shared runtime/context message handling fixed for context state without :mode

Audit and benchmark tooling

bench/vm_compiler_compat.exs
bench/vm_compiler_corpus.exs
bench/vm_compiler_opcode_coverage.exs
bench/vm_compiler_perf.exs
bench/vm_compiler_semantic_gaps.exs
bench/vm_compiler_test262.exs
test/support/vm_compiler_audit.ex
compiler acceptance and auto-mode tests

Current compiler audit status

QuickJS bytecode opcode coverage: 245 / 246 unique opcodes
- remaining missing opcode: invalid, intentionally unsupported
strict compiler Test262 statement window: 1582 / 1582 passing
semantic compiler corpus: 1000 / 1000 compiled with zero mismatches, fallbacks, or crashes
compiler invoke perf improved from 45.239µs to 42.845µs
current compiler perf audit average speedup: 1.113x

Recent validation

mix compile --warnings-as-errors
mix lint
mix dialyzer
mix test test/js/parser test/vm/auto_mode_test.exs test/vm/compiler_differential_test.exs test/web_apis/beam_fetch_test.exs test/web_apis/beam_text_encoding_test.exs test/web_apis/beam_buffer_test.exs test/web_apis/beam_streams_test.exs test/web_apis/event_source_test.exs
mix test --no-start --exclude napi_addon --exclude napi_sqlite test/web_apis/event_source_test.exs test/web_apis/beam_event_source_test.exs
PARSER_BENCH=vm_compiler_semantics ./autoresearch.sh
TEST262_LIMIT=1500 TEST262_CASE_TIMEOUT=5000 PARSER_BENCH=vm_compiler_test262 ./autoresearch.sh

Previous broad validation:

QUICKBEAM_BUILD=1 MIX_ENV=test mix test
MIX_ENV=test QUICKBEAM_BUILD=1 mix test test/vm/js_engine_test.exs --include js_engine --seed 0
mix format --check-formatted
mix credo --strict
mix dialyzer
mix ex_dna
zlint lib/quickbeam/*.zig lib/quickbeam/napi/*.zig
bunx oxlint -c oxlint.json --type-aware --type-check priv/ts/
bunx jscpd lib/quickbeam/*.zig priv/ts/*.ts --min-tokens 50 --threshold 0

…82 passing, 912 skipped (NIF failures). Result: {"status":"keep","failures":0,"passing_tests":1582,"skipped_tests":912}

…chieved — all 72 baseline failures fixed across sessions. Result: {"status":"keep","failures":0,"passing_tests":1582,"skipped_tests":912}

…enerate op attrs from Opcodes table

- Fix unused variable warnings (ref → _ref, pc → _pc) - Move for_of_start_iter helper after catch-all run/6 to fix clause grouping warning - Remove consecutive blank lines (17 credo issues)

@moduledoc

- Add Heap.Caches wrappers for: get/put_fn_atoms, get/put_capture_keys, get/put_wrap_cache, get/put_array_proto, get/put_func_proto, get/put_builtin_names, get/put_regexp_result, get/put_string_codepoints - Add Heap delegates for all new Caches functions - Update Heap.Registry @moduledoc to document every :qb_* key pattern - Replace raw Process.get/put calls in: interpreter.ex, runtime_helpers.ex, interpreter/setup.ex, compiler/runner.ex, compiler/lowering.ex, runtime/globals.ex, runtime/object.ex, runtime/regexp.ex, runtime/string.ex, object_model/get.ex, object_model/private.ex - Use Functions.put_home_object/current_home_object in interpreter.ex and private.ex

- lib/quickbeam/vm/compiler/diagnostics.ex: check/1, explain/1, helper_call_counts/1 - bench/compiler_vs_interpreter.exs: compiler vs interpreter on six JS patterns - Complete lowering tuple refactor (list→tuple for O(1) instruction access) - Apply analysis tuple refactor to cfg.ex, stack.ex, types.ex

- Fix bench/compiler_vs_interpreter.exs Heap.reset issue - Targeted benchmarks show compiler ~= interpreter on all patterns - String concat: 8.42µs (compiler), 9.17µs (interpreter) - Numeric loop: 61.33µs, 59.17µs - Array loop: 201.83µs, 207.50µs - Object field: 615.29µs, 614.04µs - Function call: 1668.50µs, 1687.06µs - Closure: 2385.31µs, 2408.00µs

…teger types Compiler now emits direct BEAM arithmetic/bitwise ops when type analysis proves operands are integers, bypassing Values.* runtime dispatch. Specialized: mod→rem, band→band, bor→bor, bxor→bxor, shl→bsl, sar→bsr.

Variables, Objects, Functions, Iterators, Coercion — RuntimeHelpers is now a thin defdelegate facade. Public API unchanged.

…ef propagation to compile_program

…ivate_kinds

…fix with-statement ASI, derived ctor flags

…r crash

… float constants, remove redundant global whitelist

…cture

…s, pass this to iterator.next(), fix declarations for AssignmentPattern/RestElement

…maining mismatches

…tocol

… for sloppy mode globals

…n body, handle AssignmentPattern params

…unsupported case (6→5)

… fix check_ctor_return stack handling (5→4)

…for_of_start/for_of_next (4→3)

…ass iodata encoding

…rectly on Function struct

… interpreter still skips decode

dannote force-pushed the beam-vm-interpreter branch from 0eb3475 to 7c1c574 Compare April 15, 2026 14:06

dannote changed the title ~~BEAM-native JS interpreter (Phase 0-1)~~ BEAM-native JS interpreter Apr 16, 2026

dannote marked this pull request as ready for review April 16, 2026 08:41

dannote force-pushed the beam-vm-interpreter branch 2 times, most recently from 75fdba5 to 527d5b9 Compare April 20, 2026 08:45

dannote changed the title ~~BEAM-native JS interpreter~~ BEAM-native JS engine and compiler Apr 21, 2026

dannote mentioned this pull request Apr 23, 2026

add example for AI code mode #6

Open

dannote added 23 commits April 25, 2026 04:07

Confirm 0 failures stable. 72→0 = 100% of baseline failures fixed. 15…

d25e6a9

…82 passing, 912 skipped (NIF failures). Result: {"status":"keep","failures":0,"passing_tests":1582,"skipped_tests":912}

Final confirmation: 0 failures stable. Autoresearch objective fully a…

e30fc6a

…chieved — all 72 baseline failures fixed across sessions. Result: {"status":"keep","failures":0,"passing_tests":1582,"skipped_tests":912}

Remove autoresearch files

86cb91d

Refactor interpreter: deduplicate helpers, collapse arity variants, g…

569f9c7

…enerate op attrs from Opcodes table

Fix all warnings, credo issues, and regroup run/6 clauses

7cbae5a

- Fix unused variable warnings (ref → _ref, pc → _pc) - Move for_of_start_iter helper after catch-all run/6 to fix clause grouping warning - Remove consecutive blank lines (17 credo issues)

Add JSThrow module and replace throw patterns across VM

eff3dd2

Add VM.Value module with type specs and guards

095bb7f

Fix O(n²) list iterator: use head/tail pattern instead of length+Enum.at

d114643

Fix O(n²) body accumulation in compiler lowering

a3ab447

Add @moduledoc to VM modules

854e2db

Add PropertyKey module, fix Value heap_ref type, extract Heap.GC

a76fed0

Split interpreter opcode clauses into Ops.* macro modules

52335a8

Split Values into focused submodules under values/

1a50bd1

Fix alias ordering in split modules (credo --strict clean)

88c30ab

Use PropertyKey.array_index in Get/Put object model

85020c5

Split compiler lowering ops.ex into focused submodules

3c59c1c

Specialize inc/dec for integer type; fix block_successors tuple_size

9690ff6

Split RuntimeHelpers into focused submodules

59302c2

Variables, Objects, Functions, Iterators, Coercion — RuntimeHelpers is now a thin defdelegate facade. Public API unchanged.

Split lowering State into Stack, Slots, Calls submodules

cd868d3

dannote added 30 commits May 4, 2026 13:21

Fix private method compilation: partition_class_body filtering, var_r…

89bfa47

…ef propagation to compile_program

Support private getters (get #x) via call_method dispatch based on pr…

411c5c1

…ivate_kinds

Support private-in operator (#x in o) via private_in opcode

494247b

Update autoresearch ideas — 6 remaining cases

69a62cc

Add Symbol/Proxy/Reflect globals, ThrowStatement, general try-catch, …

8f41919

…fix with-statement ASI, derived ctor flags

Fix with-statement ASI test after removing spurious consume_semicolon

849e328

Remove unused @ret_name module attribute

1891a2a

Handle large integers (>Int32) as float constants to prevent assemble…

c27aaec

…r crash

Emit get_var for all unresolved identifiers, handle large integers as…

00c9248

… float constants, remove redundant global whitelist

Add object destructuring with default values pattern handler

f7e57ff

Clean up unused super_class process dict, keep derived ctor infrastru…

bd63d25

…cture

Update autoresearch ideas with current status — 6 remaining failures

80cf01d

Fix for-of with custom iterables: use for_of_start/for_of_next opcode…

0a7d4b0

…s, pass this to iterator.next(), fix declarations for AssignmentPattern/RestElement

Update autoresearch ideas — native_load is the primary blocker for re…

c1c396c

…maining mismatches

Convert for-of destructuring to for_of_start/for_of_next iterator pro…

950c5db

…tocol

Fix undeclared variable assignments in function bodies — emit put_var…

235778e

… for sloppy mode globals

Resilient function compilation: stub any unsupported/crashing functio…

e94e0e9

…n body, handle AssignmentPattern params

Final autoresearch ideas update — 6 failures at hard wall

8009a0e

Implement with-statement via with_delete_var opcode — fixes the last …

13b3394

…unsupported case (6→5)

Remove unused compile_indexed_iteration_with_destructuring

bf860b8

Update ideas — all 5 remaining are mismatches, analysis of blockers

85dbc2d

Implement super() calls in derived constructors via call_constructor,…

f13ad4b

… fix check_ctor_return stack handling (5→4)

Update ideas — 4 remaining failures at hard wall (native compat + env)

b159ad1

Fix for-of Symbol.iterator: use manual iteration protocol instead of …

818f243

…for_of_start/for_of_next (4→3)

Update ideas — 3 remaining failures

5f45654

Optimize assembler: precompute offset table (O(n) vs O(n²)), single-p…

3060d8c

…ass iodata encoding

Skip decode roundtrip: store pre-resolved interpreter instructions di…

7cd4a7e

…rectly on Function struct

Revert BEAM compiler to use Decoder (needs QuickJS index convention);…

f28f21b

… interpreter still skips decode

Drop QuickJS bytecode materialization from JS compiler path

6d6bf00

Rename frontend to JS compiler and remove assembler dependency

bac0481

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BEAM-native JS engine and compiler#5

BEAM-native JS engine and compiler#5
dannote wants to merge 831 commits intomasterfrom
beam-vm-interpreter

dannote commented Apr 15, 2026 •

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Public API and runtime modes

Bytecode VM

Compiler backend

JavaScript semantics covered

Static analysis and cleanup

Audit and benchmark tooling

Current compiler audit status

Recent validation

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dannote commented Apr 15, 2026 •

edited

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