crypto.createECDH returns a native ECDH handle backed by mbedTLS for
prime192v1, secp224r1, prime256v1, secp384r1, secp521r1, secp192k1,
secp224k1, secp256k1, brainpoolP256r1, brainpoolP384r1 and
brainpoolP512r1. generateKeys, computeSecret, getPublicKey,
getPrivateKey, setPrivateKey, setPublicKey and ECDH.convertKey follow
Node 24: compressed, uncompressed and hybrid points, input and output
encodings, the private key range, key pair validation, and Node's error
codes and messages.
Curve names follow OpenSSL's short-name lookup: names of other curves
from crypto.getCurves() are refused at compile time when literal and
throw a coded SC2020 error when computed, other OpenSSL short names
throw ERR_CRYPTO_OPERATION_FAILED, and unknown names throw
ERR_CRYPTO_INVALID_CURVE. Calls whose arguments no @types/node overload
accepts, and computeSecret(view, encoding), are refused at compile time.
The runtime unit scr_ecdh.c links, with the mbedTLS archive, only into
programs that use ECDH. wasm32-wasi builds refuse it.
ScrArr stores len and cap as 32-bit fields and no longer stores the
state pointer. The dense states share the values' allocation and run
backward from its end: the state of slot i is at
data + cap * (slot width + 1) - 1 - i. Removing slots from the front
(shift, splice(0, n)) advances data and lowers cap, which leaves every
remaining state at its address; the head room size, needed only to free
or reallocate the block, is kept in the vacated slot before data. On
64-bit targets the header goes from 64 to 48 bytes, and from 36 to 32
bytes on wasm32. Array lengths were already limited to 2^32 - 1.
The emitted code loads len and cap as i32 and zero-extends them, and
computes state addresses from data and cap. Runtime loops compute the
end of the states once per call. Local array reads load data once for
both the state and value paths. A local or strict element read whose
index is a loop's induction variable reads slots above the hole-free
prefix through the runtime: an inline state check there makes LLVM keep
-1 - i as a second induction variable, which costs a register in the
loop.
Bulk operations do not read back states they just wrote: an append to
an array whose hole-free prefix reaches its length moves the prefix bound
to the new length, a copy from below the source's prefix writes value
states without reading the source's, and releasing a string array skips
the state checks below the prefix. Copies of up to eight slots and of
short state runs use overlapping word moves instead of a call. Emitted
element access computes the state address only on the state-checked
path. Without these, programs that build many small arrays with split or
slice ran 2-4% slower than with the separate state pointer.
Integer loops over an array's length compare the counter with the i32
length field in 32 bits; the counter never exceeds 2^32 - 1 there. The
array-length stability proof accepts Map and Set reads (get, has, size)
and checked union extractions (`x!`), which run no user code, so loops
that look up maps keep the dense fast copy, which tests the hole-free
prefix once before the loop.
Small constructions with the small allocator request 6 slots, so their
blocks stay 112 bytes, now with 7 inline slots (6 after a collector
header). With 96-byte blocks of 5 slots, programs that free and reuse
many small arrays ran 15-20% slower.
RUNTIME_ABI_VERSION goes from 22 to 23.
The darwin-arm64 runtime pack matrix repeated the common matrix's base
and optional runtime source lists and its variantsFor table, so a new
runtime source needed the same line in both files. The common matrix
now exports BASE_RUNTIME_SOURCES, OPTIONAL_RUNTIME_SOURCES and
variantsFor, and the darwin-arm64 matrix imports them. A comment on the
lists notes that their order is the link order of an executable's
runtime units. Both matrices evaluate to the same objects as before.
crypto.subtle.importKey('raw', ...) for HMAC keys, HMAC sign and verify,
and the SHA-1/SHA-2 digests compile through the crypto global, with
CryptoKey values as native handles. scr_webcrypto.c is only the WebCrypto
layer (Web IDL conversion, algorithm normalization, the CryptoKey handle,
promise wrapping and Node's TypeErrors and DOMExceptions) over node:crypto's
digest core and deferred promise queue. It links only into programs that
call these methods (the new webcrypto link feature). Other algorithms, the
jwk format and the other SubtleCrypto methods are SC2020 refusals.
The real jose@6.2.12 HS256 path (SignJWT, jwtVerify) now runs natively. It
also needed four compiler fixes: object patterns of positions and length
over arrays, the Uint8Array base64/hex feature probes, a compile-time
String.fromCharCode.apply, and structuredClone of a parameter whose default
is {}.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
The process.emitWarning replacement and the stdin encoding, string data
listener and stdio 'resize' support changed runtime functions every
program with the dyn-async or events unit links (the shared warning
paths, stdin delivery, the process stream object) and grew their
thread-local state. That code now compiles only into new runtime-pack
variants, SCR_WARNING_REPLACE of scr_async_dyn.c and SCR_STDIO_EXTENDED
of scr_events.c, which the link selects when the program assigns
process.emitWarning or reaches setEncoding, a string 'data' listener or
'resize'. The default objects are byte-identical to before, so other
executables do not change. The development and sanitizer builds pass the
same defines.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Stage S3 of the two-tier design: dynamic-tier functions compute with
jsval, a new IR type holding a 64-bit NaN-boxed word whose numbers,
booleans, undefined and null are immediates, so a number between two
dynamic operators is no longer a heap node.
- IR: the jsval type and js.* builtins (operators and the boundary
conversions fromDyn/toDyn/fromF64/fromBool/fromStr/fromBigInt/toF64).
The jsval pass rewrites dynamic-tier functions after tier assignment:
operator chains, comparisons, number checks and truthiness of operator
results run on jsvals; dyn locals become jsval locals when that saves
boxing; dynamic functions called only from dynamic functions return a
jsval. IR version 17 serializes each function's tier.
- Runtime: scr_js.h and scr_js_value.c behind the dynTier feature
(invariant I3); static runtime units never include scr_js.h.
- Backend: number cases inline (immediate doubles and NUM cells), always
inlined jsval retain/release; 32-bit targets keep boxed cells.
- Interprocedural analyses see jsval conversions as the dyn forms they
replace, so no fact about a static function changes.
Static functions are untouched: typed programs and the self-hosted
compiler's static functions compile to byte-identical LLVM.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
SCRIPTC_YOUNG_NURSERY=1 at compile time makes an executable allocate
traced, program-owned class instances and records young and link the
collector unit built with SCR_YIN (a runtime pack variant of
scr_cycle.c; libraries never get it). The emitted constructor lists the
object in a per-thread nursery and marks its header: generation
SCR_CYC_YOUNG and its nursery index under the buffered bit, so every
existing release path treats it as a buffered candidate (no call while it
stays alive; scr_cyc_on_dead takes it out of the nursery at its death).
A nursery collection (whenever 4096 young objects are live, at collection
points, before full sweeps and limited passes) counts each young object's
references from other young objects, marks from the objects whose count is
below their reference count (referenced from outside the nursery: stacks,
globals, older objects, runtime structures, FFI, fibers, coroutine
frames), frees what stays unmarked, and gives up the dead set's outgoing
edges after the teardowns. The counts are recomputed at every collection
instead of maintained by a store barrier, so soundness rests only on the
invariants trial deletion already needs. Survivors join trial deletion's
nursery and outside roots become candidates; trial deletion walks young
objects it reaches as nursery-level objects. Per-type admission statistics
send types that do not die in young cycles back to trial deletion for a
while. Publication takes young objects out of the nursery. The RC audit
build checks nursery membership and counts at every collection.
With the flag off, the compiler emits and links exactly what it did
before (249 programs and the self-hosted compiler compared
byte-identical). Measured with the flag on: cg-rings -38%, cg-pairs -27%,
the runtime suite geomean -0.3% (published-graphs +3.4%), the self-hosted
compiler neutral; shapes whose cycles go through arrays or closures
(phase 2) pay without gaining.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
ThreadSlots<K, V> holds one value per key and thread, like a WeakMap that
each thread has its own copy of; under Node.js it is a WeakMap per name
and thread. Setting a value never writes the key, so values can be set on
published keys.
Classes used as keys carry a 32-bit slot word after their header words,
assigned on the first set for a key (with a compare-and-swap for a
published key) and never reused. Each family has one block per thread
that maps slot indices to values through pages of 1024 entries. get and
has are inline reads of the slot word, the page and the entry; set and
delete call scr_slots.c, which holds one reference to each value. A key
class's free paths release the key's values, and thread exit releases the
rest.
fs.cpSync, fs.cp and fs/promises cp compile with every option:
dereference, errorOnExist, filter, force, mode, preserveTimestamps,
recursive and verbatimSymlinks. They follow Node's two implementations.
cpSync follows cp-sync.js over the fs binding: copy errors are plain
Errors with a code, std::error_code failures throw an ErrnoException,
and links inside a copied directory point at their canonical targets.
fs.cp and fs/promises cp follow cp.js, whose copy errors are
SystemErrors with code, info, errno, syscall and path.
Options and paths validate in Node's order with Node's errors. filter
runs for the top-level paths and each entry in Node's order; an async
filter must return a promise that is already settled, and a pending one
throws SC2020. The callback and promise forms complete the copy before
the callback runs or the promise settles. Windows builds throw SC2020.
The copy lives in the new scr_fs_cp.c. Directory walks keep their frames
on the heap, so deep trees also copy on a fiber's stack. File contents
copy with sendfile on Linux, and COPYFILE_FICLONE uses FICLONE
where it exists. ScrError gains the SystemError context and the
ErrnoException key order, with matching fields in the compiler's Error
layout. The stored fs.cp callback uses the same implementation.
Corpus 5567-5571 cover the sync, callback and promise forms, errors,
symlinks and 1500-level trees.
Release executables now import small runtime functions from runtime
bitcode, as speed executables do, so LLVM can inline them into program
code. Release units keep the runtime compiler's own objects, unchanged,
and additionally ship the bitcode of the same compilation reduced by the
helper's prune-import. Their unit-local symbols stay local, so only
bodies that need none of them can be imported, which keeps the import
small: about 1.3 MB per program.
Only unsanitized programs small enough for one codegen partition import.
Every partition reads the bitcode again; on the Effect fixtures (64
partitions) import cost +2..18% compile time and +4.3..4.9% size, so
partitioned release builds stay exactly as before. Speed is unchanged.
Measured against main in Linux Vercel Sandboxes, same-VM interleaved
medians (bench-runtime --layouts=4 --runs=16), on two VMs:
- bench-runtime (31 workloads): -1.3% (8 faster, 0 slower) and -1.0%
(1 slower, typed-array-scan-workers +3.2%); size +0.0%
- js-compiled suite (22 programs): -2.2% and -1.8%; size -0.1%
- cold builds of all 53 programs, interleaved: +3.1%; helper time per
build +40..235 ms
- Effect fixtures: byte-identical to main
fs.createReadStream, fs.createWriteStream and FileHandle
createReadStream, createWriteStream and readLines return runtime
Readable and Writable streams (scr_fs_stream.c), as do new fs.ReadStream
and new fs.WriteStream in JavaScript sources. They follow
lib/internal/fs/streams.js on the stream engine:
- _construct opens the file, then emits 'open' (with the fd) and
'ready'; _read reads up to end; _write retries short writes as
writeAll does; _destroy waits for I/O in flight, then closes (with
fsync first for the flush option). Every open, read, write, fsync and
close runs on the shared worker pool.
- Options are checked in Node's order: getOptions, options.fd or the
path, start, end, then highWaterMark, encoding, emitClose and
autoClose. flags and mode are checked when the file opens, so their
errors arrive as 'error' events.
- bytesRead, bytesWritten, pending, path and close(cb) compile, also
through untyped values (close() there).
A FileHandle stream holds a reference on the handle; closing the stream
releases it and closes the handle unless autoClose is false.
FileHandle.close() follows Node's reference count: it waits for the
streams over the handle and runs their close(). readLines is a readline
Interface over createReadStream with crlfDelay: Infinity.
The stream engine gains Node's _construct (reads, buffered writes,
finish and _destroy wait for construction; destroy errors combine with
aggregateTwoErrors) and _writev, both internal. Writable.destroy() now
runs the buffered write callbacks and end() callbacks (errorBuffer),
which it dropped before. highWaterMark in a dynamic options record is
checked as getHighWaterMark does, and for await over a constructing
stream waits for construction.
Numeric flags, the fs, signal and windowsHandle options, non-UTF-8
write encodings, option functions that replace the file implementation,
and instanceof fs.ReadStream/WriteStream are refused.
Corpus 5546, 5547 and 5554 cover both lanes against Node 24.22.
@scriptc/experimental exports InternTable<K, V>: a named table that every
thread of a scriptc program shares and that each thread has its own copy
of under Node.js. Keys are strings or numbers with Map equality; values are
published (@scriptc/threads) when stored, and the first stored value of a
key is kept. Members are get, has, size, getOrInsert and
getOrInsertComputed.
The runtime table (scr_itable.c) splits each table into 64 segments.
Lookups take no lock and do not write; inserts take a segment's spin lock
for a probe and a few stores, and callbacks run without a lock. Number
tables keep keys and values in the index; string tables keep entries in
segment-owned chunks behind tagged slots. Replaced indexes are kept.
The compiler lowers the class to a synthetic class with one f64 handle
field and five intrinsics, with interned helpers per member and type and
an in-place lowering of getOrInsertComputed that creates a function
expression callback only on a miss. Stored values go through the publish
intrinsic, so their types get the write guard. scriptc refuses names that
are not string literals, one name opened with different type arguments,
and key or value types a table cannot store.
scr_publish walks small graphs in inline buffers and reads
SCRIPTC_PUBLISH_TRACE once, instead of allocating and calling getenv on
every call.
Release builds now emit the string retain and the dyn retain and release
fast paths inline. The dyn release decides the cases scr_dyn_release
decides by kind and calls scr_dyn_release_survivor for capsules and
handles. String releases and the other families stay runtime calls, as
string-heavy programs have many release sites. The speed posture keeps
every fast path and gains the dyn release. The runtime ABI version moves
to 21 because program objects call the new runtime entry point.
createHash, createHmac, crypto.hash, pbkdf2, pbkdf2Sync, hkdf and hkdfSync
accept every digest crypto.getHashes() lists in Node 24: SHA-512/224,
SHA-512/256, SHA-256/192, SHA3-224 to SHA3-512, Keccak-224 to Keccak-512,
SHAKE128, SHAKE256, KECCAK-KMAC-128, KECCAK-KMAC-256, RIPEMD-160,
BLAKE2b-512, BLAKE2s-256, SM3 and MD5-SHA1. The new runtime unit
scr_hash.c implements Keccak, RIPEMD-160, BLAKE2b, BLAKE2s and SM3, and
is registered in both runtime pack matrices and the C-compile path.
Names resolve as Node 24.22 resolves them: case-insensitively, with
OpenSSL's provider aliases and object identifiers, ending at the first
NUL, and with trailing spaces allowed except on the RSA signature
aliases. "dss1" and "DSS1" are SHA-1, and createHash and crypto.hash
accept "dss1" in any case. The compiler no longer refuses literal digest
names outside SHA-1/SHA-2 and MD5; unknown names throw Node's errors at
run time.
SHAKE and KMAC digests use their default output lengths. createHmac
rejects them with Node's OpenSSL error, pbkdf2 with "xof digests not
allowed", and hkdf with "Deriving bits failed". pbkdf2 with a key length
of 0 now fails with "Deriving bits failed" as in Node 24.22, and the
callback forms pass these failures to the callback.
PBKDF2 computes the keyed HMAC states once instead of on every
iteration, and digest contexts are cleared with memset and a compiler
barrier instead of a byte loop. The Keccak permutation, the RIPEMD-160
and BLAKE2 compression functions and the SM3 rounds are unrolled with
constant indices.
Blob and File (globals and node:buffer exports) compile to native
handles in the new scr_blob.c, following Node 24.22's
lib/internal/blob.js and file.js. A Blob is a window over a shared,
immutable byte store plus the byte length of each part. Sources (strings,
typed arrays, DataView, ArrayBuffer, Buffer, other Blobs, Set and Map)
convert as a Web IDL sequence, with each non-buffer part converted to a
string, before the options are read, and are copied when the Blob is
built. The constructors throw Node's Web IDL TypeErrors and its
ERR_INVALID_ARG_TYPE, ERR_INVALID_ARG_VALUE and ERR_MISSING_ARGS errors,
and read and convert their options in Node's order. The type is
lowercased, or cleared when it holds a character outside U+0020..U+007E.
endings: "native" rewrites CRLF, CR and LF to the platform's line break.
File takes its name with lone surrogates replaced and lastModified as a
number (Date.now() when absent).
slice() converts its offsets as a [Clamp] long long (rounded half to
even) and keeps the parts Node's data queue keeps. text(), bytes() and
arrayBuffer() settle on the same microtask turn as in Node, which depends
on the part count. util.inspect prints Node's `Blob { size, type }` and
`File { ..., name, lastModified }` forms, with `[Blob]` past the depth
limit. String() and toString() give the class tag, JSON.stringify gives
{}, and structuredClone returns a new Blob or File over the same bytes.
instanceof works for both spellings. stream(), textStream() and the
Object.prototype members other than toString() fail at compile time.
Non-array iterables other than Set and Map throw SC2020.
Three handle-table additions support this: a structuredClone hook, a
JSON `{}` flag, and a bracketed past-depth inspect flag. scr_blob.c is an
optional unit selected by dynAsync, because the dynamic dispatch path
boxes its reads as dyn promises through scr_async_dyn.c.
Corpus 5285-5290 and a node-types fixture check the behavior against
Node.
Deflate, Inflate, Gzip, Gunzip, DeflateRaw, InflateRaw and Unzip, from
createGzip() and the other factories or new zlib.Gzip(options), are
runtime Transform streams over zlib.
- scr_zlib.c gains a step engine that follows Node's ZlibContext: lazy
init, Unzip's gzip-magic detection, the dictionary retry, Gunzip's
multi-member loop, and Node's error messages, codes and errno.
- scr_zlib_stream.c, linked when a program uses zlib and streams, runs
each write as engine steps on the worker pool with Node's output
chunking, the finish flush from 'prefinish', read-side backpressure,
flush(), params(), close(), reset() and bytesWritten, and validates
options in Node's order.
- The fallback declarations add the classes, factories and a
literal-typed ZlibConstants; zlib.constants and the module-level Z_*
copies bake as literals. Brotli streams and their factories are refused
by name.
Corpus programs 5370-5377 cover round trips, chunking and event order,
errors, options, flush and params, stream/promises, constants and
backpressure.
The Readable operators (map, filter, forEach, toArray, some, find, every,
flatMap, drop, take, reduce) run over string and Buffer chunk streams with
Node's ordering, errors, and concurrency, highWaterMark and signal options.
Readable.from reads arrays lazily and accepts the objectMode and
highWaterMark options, and its JavaScript form follows from.js's checks.
stream.compose returns a Duplex over a pipeline of stream instances.
pipeline now follows pipeline.js: per-stream destroyers and eos watchers,
and the callback on a tick once every watcher finished. 'finish' waits for
a pending _final or _flush callback, and a failed synchronous write emits
'error' one tick later, as in Node.
Chris Tate