An instance of a compiled class reaches untyped code as a capsule, which
a property site sent to its helper on every read: the helper normalizes
the capsule, tests each class's key in turn, and loads the field.
A read site now emits the helper's plain field branches inline. A
capsule whose key pointer is one of those classes' keys loads the field
from its instance and shares the inline hits' conversion. A branch is
emitted only when its field holds a plain dyn cell and every subclass
the helper's normalization can rebox the key to reads the same field
from the same slot. Getters, bag properties, unset fields and other
capsules keep the helper.
The static hello binary grew past the 96 KiB ceiling of the runtime
tree-shaking test on Linux hosts that link with GNU ld (99,040 B). CI does
not see it: its pinned LLVM ships ld.lld, which the compiler prefers, and
hello links to about 65 KB there. The Sandbox gate installs Ubuntu's
clang-22 without lld, so it links with GNU ld.
dd418b067 crossed the ceiling (98,032 -> 98,960 B). Its scr_glibc_math.c
defines floor, fmod, frexp and other glibc names as hidden functions so a
program can start without libm. With GNU ld that cannot work: ld decides
--as-needed before section GC, so the runtime's unreachable code keeps
libm needed, and it keeps every regular definition of a name a needed
shared library defines, hidden or not. Every executable carried the whole
unit (about 2.5 KB of code and unwind data) and still loaded libm. Links
without lld now leave the unit out; its functions answer what glibc's do.
192ea3247 installed scr_gen_tag_reader from a load-time constructor in
scr_async.c. A constructor is a link root on every format, so each
executable kept scr_gen_tag and, with GNU ld, all of scr_async.c's string
literals (about 1.1 KB). The generator runtime now installs the reader
when it creates a generator, the only time a reader can be needed.
Hello is now 93,928 B with GNU ld and 65,472 B with lld.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
An Array subclass's type maps to its element array type, so a field such
as TreeNode.kids holds a Kids instance in a slot typed as an array of
TreeNode. The collector visits such a slot as an array, which has a
collector header when its element ops trace, but the class only got a
header when its own class unit was on a cycle, and the collector read a
header the instance did not have. An Array subclass now carries a header
whenever an array of its element type does, and its collector descriptor
visits its elements instead of naming no children.
An element read of an array of Array subclass instances is a union with
undefined, and 'instanceof' against the class answered false for it. A
union now tests its array arms' class at run time.
The implicit toolchain probe preprocesses every system header that the
runtime and vendored sources spell in one source file. When the compiler
rejected one of them, the whole probe failed, and the build continued
without the native cache and without program sharding.
When the compiler rejects the probe source, each header is now
preprocessed on its own, and a header that the compiler rejects on its
own is left out of the dependency set, as an absent header is. The probe
still fails when the compiler rejects every header.
fields.generated.ts reads IR nodes' fields by name, so a field ir.ts gains
after the last `pnpm generate:ir-fields` is skipped by the walkers until
someone regenerates the file; `--check` in CI reports it, but only on the
run that looks.
The generator now ends the file with type-level checks, one per node kind
and per nested record the walkers enumerate: a field outside the list the
file was generated from fails type checking with the field's name, and so
does a field read as a scalar (no string, no object) that can now hold a
string or an object. Fields the file reads already fail type checking when
they are removed or change type. The checks are types only and emit no
code.
A template literal of strings and numbers reserved 32 bytes for each
number, the longest number text, and kept that capacity for the result's
lifetime: an 8-byte name built from two numbers used a 96-byte block. The
numbers now format into a stack buffer first, so the result is allocated
once at its exact length.
A dynamic-tier property site tested only the first entry of its cache
inline and called scr_js_get_probe (or scr_js_store_probe) for anything
else. A site that sees two layouts, such as object literals of one
record built in two key orders, then took the out-of-line probe on
every access to objects of its second layout.
Sites now test the first two entries inline, own or prototype, for
reads and replacing writes. The probe still answers the third and fourth
entries, misses and everything that is not plain data.
A typed-array loop version runs a checked copy and one or two fast copies
of the loop, and each copy repeats every nested loop together with the
nested loop's own version. A loop whose guard proves only accesses outside
its nested loops, which run once per pass, now runs as written when a
nested loop accesses typed arrays; the nested loops still version their own
accesses. The loop versions as before when the guard proves the bounds of
an access inside a nested loop, or, in a worker program, the ownership of
an access inside a nested while loop, which never versions for ownership
alone.
Spectral-norm's paired row sums no longer copy their column loop for the
row loop's two stores. The worker program's au and atu functions are
102 KB of LLVM text instead of 236 KB each, and the program 519 KB instead
of 786 KB.
Corpus typed-array-nested-loop-versions covers row loops that store past
the end or at negative, fractional and NaN rows, views the nested loop
writes, and a nested while loop.
String.prototype.indexOf took its byte-search fast path on a proven-ASCII
receiver only when the start index was not positive. A positive start went
through the general path: ToIntegerOrInfinity, the surrogate-needle check,
and UTF-16 to byte conversions in both directions, although byte offsets
are UTF-16 indexes in an ASCII string. The fast path now covers every start
index: a positive start truncates and clamps to the length, where only the
empty needle is found, and the search runs from that byte offset.
The implicit toolchain probe includes every system header that the
runtime and vendored sources spell, under __has_include. clang ships
<riscv_vector.h> for every target, and through clang 18 including it
without the RISC-V vector extension is an #error. Since the vendored
zlib's adler32_simd.c spells it, the probe failed with clang 18, which
disabled the native cache and program sharding: a sanitized dev build
then compiled the whole program as one translation unit.
The probe now includes <riscv_vector.h> only where __riscv_vector is
defined, and the probe's header test covers it and a riscv64 target.
Every unbounded recursion repeats some cycle of the call graph, so a
stack check in one function of each cycle bounds it. stackCheckedFunctions
now picks a feedback vertex set of the stack-check graph greedily (the
function with the most caller-callee pairs first) instead of checking
every function on a cycle, and adds a check where a run of unchecked cycle
functions would exceed 32 calls, so the stack used between two checks
stays of the same order as before.
Worker entry polls follow: a synchronous function on a cycle that may
throw needs no entry poll, since a descent that never returns ends at a
checked function of its cycle. NoThrow contracts keep the model in which
every function on a cycle checks, a superset that does not depend on the
choice.
A small helper called once per element, such as
function pick(list: Gene[], rand: number): number {
for (const gene of list) if (rand < gene.c) return gene.sc;
return list[list.length - 1]!.sc;
}
called from a loop over the elements, is often past LLVM's inline cost
threshold once its loop versions and checks are emitted (fasta's
randomCode costs 430 against a threshold of 225), so every element pays a
call, the spills around it, and checks the caller's loop cannot hoist.
findLoopCallees (loop-callees.ts) finds functions that are synchronous,
non-generator, capture nothing, call nothing (no call, callValue,
virtualCall, dynCall, dynInvoke, new, newValue, newPromise, ffiCall or
await), have at most 12 statements and one loop, and have one or two
direct call sites in the module, each inside a loop of its caller. The
emitter marks those calls `alwaysinline` (a call-site attribute, so the
function's definition is unchanged). Library modules and debug builds
keep LLVM's cost decision.
stableFileName used node:path's relative(), which returns paths with `\`
separators on Windows. The module tags hash that name, so Windows builds
named the functions of every non-entry module differently from Linux
builds, and a profile or layout collected on Linux no longer matched them.
Structural positions used the same name.
portableRelativePath computes the relative path with the platform's rules
and writes it with `/` separators, as tsgoPath does for checker paths.
Linux and macOS names are unchanged.
`skip || (flag ? warnA() : warnB())`, with void calls in both arms, as
React's development warnings write it, failed with SC9001 "ternary must
not be void": the statement lowered the logical as a value, and a
conditional of void calls has none. A logical whose result is discarded
now lowers as `if (!skip) ...` (or `if (skip) ...` for `&&`) when its
right operand needs no value: its type maps to void, or it is a logical
or comma expression whose last operand needs none. This holds in
statements and in a for loop's initializer and update, and for a
generic callback's conditional whose type parameter maps to void.
Closes#2322
Co-authored-by: MathurAditya724 <57684218+MathurAditya724@users.noreply.github.com>
The runtime vendored zlib 1.3.1 and archived it at -Os, and host C-lane
builds linked the system libz, so deflate, raw deflate and gzip output
differed from Node's at every level. The vendored copy is now Node
v24.22.0's deps/zlib (Chromium's zlib, 1.3.2.1-motley-285e94b), built at
-O3 with the units and defines Node's zlib.gyp selects per target: the
SSSE3 Adler-32 and SSE2 inflate and slide-hash code on x86-64, the NEON
and ARMv8 CRC-32 code on arm64, and the portable code on wasm32. The SIMD
units check the CPU at run time and give the same output, so compressed
bytes match Node's on every target.
zlibInputs (runtime-pack-common/scripts/zlib-inputs.mjs for the runtime
packs, vendor-inputs.ts for Zig cross builds and the sanitized runtime)
holds the per-target table, and a unit test keeps the two identical.
Every C-lane driver now links the vendored objects instead of -lz.
Chromium's BSD license ships beside zlib's in the runtime packs.
Corpus 8405 compares compressed bytes with Node across levels,
strategies, memLevel, windowBits, dictionaries and flushing streams;
8406 covers chunked inflation with small input pieces and output chunks.
An integer clone reads a number array's element as an 8-byte double. A
number array proven to hold only int32s keeps 4-byte int32 slots
(SCR_ELEM_I32), so the clone read such an array at the wrong width: it
returned wrong values, and near the array's end it read past the slots.
The clone now tests the array's element kind: int32 slots load as 4-byte
int32s, double slots load as doubles and keep the exact-int32 test, and
any other storage bails to the ordinary body.
New corpus program: integer-clone-int32-slots.ts.
Chris Tate