Package Exports

@webassemblyjs/wasm-edit

This package does not declare an exports field, so the exports above have been automatically detected and optimized by JSPM instead. If any package subpath is missing, it is recommended to post an issue to the original package (@webassemblyjs/wasm-edit) to support the "exports" field. If that is not possible, create a JSPM override to customize the exports field for this package.

Readme

@webassemblyjs/wasm-edit

Rewrite a WASM binary

Replace in-place an AST node in the binary.

Installation

yarn add @webassemblyjs/wasm-edit

Usage

Update:

import { edit } from "@webassemblyjs/wasm-edit";

const binary = [/*...*/];

const visitors = {
  ModuleImport({ node }) {
    node.module = "foo";
    node.name = "bar";
  }
};

const newBinary = edit(binary, visitors);

Replace:

import { edit } from "@webassemblyjs/wasm-edit";

const binary = [/*...*/];

const visitors = {
  Instr(path) {
    const newNode = t.callInstruction(t.indexLiteral(0));
    path.replaceWith(newNode);
  }
};

const newBinary = edit(binary, visitors);

Remove:

import { edit } from "@webassemblyjs/wasm-edit";

const binary = [/*...*/];

const visitors = {
  ModuleExport({ node }) {
    path.remove()
  }
};

const newBinary = edit(binary, visitors);

Insert:

import { add } from "@webassemblyjs/wasm-edit";

const binary = [/*...*/];

const newBinary = add(actualBinary, [
  t.moduleImport("env", "mem", t.memory(t.limit(1)))
]);

Providing the AST

Providing an AST allows you to handle the decoding yourself, here is the API:

addWithAST(Program, ArrayBuffer, Array<Node>): ArrayBuffer;
editWithAST(Program, ArrayBuffer, visitors): ArrayBuffer;

Note that the AST will be updated in-place.