string-wasm

A simple implementation of some string functions from libc in WebAssembly.

Modules

string.wasm

Contains a simple implementation of strcat, strcmp, strcpy and strlen functions from libc.

string_opt.wasm

For now, contains only an optimized version of strlen function, that reads four bytes per iteration.

Building and Testing

Prerequisites:

• wat2wasm (from WebAssembly Binary Toolkit)
• Node.js (only for running tests)

Build .wasm files

To build string.wasm:

$ wat2wasm -o build/string.wasm src/string.wat

To build string_opt.wasm:

$ wat2wasm -o build/string_opt.wasm src/string_opt.wat

Or build the two using Makefile:

$ make all

Test the .wasm modules

First, build the tests.wasm module:

$ wat2wasm -o tests/tests.wasm tests/tests.wat

Then, run the tests with Node.js:

$ node tests/tests.js

Note: For now, only string.wasm is tested.

Build .wasm files and run tests (using Makefile)

$ make tests