Chris Tate 33be2a80ee Store a table entry for if/else chains that store literals to one element
An if/else-if chain that compares one number local with integer literals
and stores a number literal to the same typed-array element in every arm,
including a final else, such as

    if (x === 97) a[i] = 0;
    else if (x === 116) a[i] = 1;
    else if (x === 99) a[i] = 2;
    else a[i] = 3;

is now emitted as one store of an entry of a constant table indexed by
the local's value (constant-choices.ts). On input whose cases do not
repeat in a pattern, such as the bases of a DNA sequence, the branches
mispredict; LLVM keeps them, because cases this far apart are too sparse
for its own switch tables.

The chain needs at least three distinct values within 256 of each other.
The table covers the cases' span, or the local's proven integer range
when that range has at most 256 values, in which case no test is
emitted. Otherwise a value that is not an exact integer in the table's
span (NaN, a fraction, or a value outside it) stores the final else's
literal, chosen with a select. The first arm wins for a repeated
value, and -0 selects the arm for 0, as strict equality does. The store
is the arms' own (the same receiver and index), converted to the
element's type as each arm's would be. Debug builds keep the arms.

k-nucleotide's transform of the input sequence uses this form: its
median wall time drops from 2.71 s to 2.21 s.
2026-10-26 01:04:42 -05:00
2026-10-16 10:33:14 -05:00
2026-10-25 06:38:44 -05:00
2026-10-14 17:27:02 -05:00
2026-10-25 11:26:13 -05:00
2026-07-22 18:08:04 -05:00
2026-10-22 04:10:59 -05:00
2026-10-25 21:21:26 -05:00
2026-10-25 21:21:26 -05:00
2026-07-22 18:08:04 -05:00

scriptc

Vercel Labs Experiment npm version: scriptc License: Apache-2.0 npm downloads per month: scriptc

scriptc compiles TypeScript and JavaScript to native executables and WebAssembly. It uses the types checked by the TypeScript compiler to generate machine code, and the output runs without Node.js installed. npm packages your program imports compile along with it. Code scriptc can't compile is reported at build time with a diagnostic and, where available, a rewrite hint.

scriptc is experimental and supports a subset of JavaScript, TypeScript, and Node.js APIs. Run scriptc coverage on an existing program to see how much of it compiles, and see the limitations and Node.js compatibility reference for details.

Installation

Install with Node.js 24 or later and npm:

$ npm install -g scriptc

The installed compiler runs natively on macOS, Linux, and Windows. Node.js is needed only to install it and to run WASI modules with scriptc run. Standalone compiler archives are also available from GitHub Releases.

Building executables requires a linker and the platform SDK or sysroot. See the quickstart for prerequisites and platform support for host requirements, cross-compilation, and WebAssembly.

Build a program

Create hello.ts:

const who = process.argv.length > 2 ? process.argv[2] : "world";
console.log(`hello, ${who}`);

scriptc run compiles the file and runs the result:

$ scriptc run hello.ts
hello, world

scriptc build writes an executable:

$ scriptc build hello.ts -o hello >/dev/null
$ ./hello scriptc
hello, scriptc

These examples use POSIX shell syntax. On Windows, build hello.exe and run it with .\hello.exe.

Use scriptc coverage hello.ts to check what compiles before you build. See coverage reports for details.

Use Node APIs

Supported Node APIs compile to the native runtime. For example, server.ts:

import { createServer } from "node:http";

const server = createServer((req, res) => {
  res.setHeader("content-type", "application/json");
  res.end(JSON.stringify({ path: req.url }));
});

server.listen(8080, () => {
  console.log("listening on http://localhost:8080");
});
$ scriptc build server.ts -o server >/dev/null
$ ./server
listening on http://localhost:8080

Use npm packages

npm packages compile into the executable with your code, so it doesn't read node_modules at runtime.

Create cli.ts:

import pc from "picocolors";

console.log(pc.green("hello from scriptc"));
$ npm install picocolors
$ scriptc build cli.ts -o cli >/dev/null
$ ./cli
hello from scriptc

Package support is partial. See npm dependencies for which packages compile and how to check them.

Documentation

Contributing

See CONTRIBUTING.md for source setup, testing, native artifact builds, and docs development.

S
Description
GitHub Trending: vercel-labs/scriptc
Readme Apache-2.0
180 MiB
Languages
TypeScript 68%
C 23.4%
JavaScript 7.9%
C++ 0.6%