eagler-teavm

Branch: eagler-r1

Fork of TeaVM for compiling EaglercrafX's WASM GC runtime

Changes in this fork:

• Implemented malloc/free in TeaVM's WASM GC backend for allocating direct buffers from a WebAssembly.Memory
• Implemented memset and memcpy intrinsic functions
• Made TeaVM's Address class work in the WASM GC backend
• Added support for the @Unmanaged annotation in the WASM GC backend

New API Additions

org.teavm.interop.DirectMalloc

• public static native Address malloc(int sizeBytes); - Allocates sizeBytes of memory from the WebAssembly memory object, if the integer value of the returned address is 0 then the program has run out of memory
• public static native Address calloc(int sizeBytes); - Allocates sizeBytes of memory from the WebAssembly memory object and fills it with zeros, returns 0 if out of memory
• public static native void free(Address ptr); - Frees an address that was previously allocated with malloc or calloc, bad things will happen if you free an address that was never allocated
• public static native void memcpy(Address dst, Address src, int count); - Intrinsic, uses the memory.copy instruction to efficiently copy count bytes from src address to dst address
• public static native void memset(Address ptr, int val, int count); - Intrinsic, uses the memory.fill instruction to fill count bytes at ptr address with bytes of val value
• public static native void zmemset(Address ptr, int count); - Intrinsic, uses the memory.fill instruction to fill count bytes at ptr address with zeros

build.gradle: teavm.wasmGC section

• directMallocSupport - Set to true to enable the DirectMalloc class in your build
• minHeapSize - Initial DirectMalloc heap size in megabytes
• maxHeapSize - Maximum DirectMalloc heap size in megabytes

You will not recieve support from the developer of TeaVM regarding any issues caused by this fork!

TeaVM

See documentation at the project web site.

Useful links:

• Getting started
• Gallery
• Site source code repository
• Discussion on Google Groups

Building TeaVM

Simply clone source code (git clone https://github.com/konsoletyper/teavm.git) and run Gradle build (./gradlew publishToMavenLocal or gradlew.bat publishToMavenLocal). You should build samples separately, as described in corresponding readme file.

Useful Gradle tasks

• :tools:classlib-comparison-gen:build – build Java class library compatibility report. result is available at: tools/classlib-comparison-gen/build/jcl-support

Embedding TeaVM

If you are not satisfied with Maven, you can embed TeaVM in your program or even create your own plugin for any build tool, like Ant or Gradle. The starting point for you may be org.teavm.tooling.TeaVMTool class from teavm-tooling artifact. You may want to go deeper and use org.teavm.vm.TeaVM from teavm-core artifact, learn how TeaVMTool initializes it. To learn how to use TeaVMTool class itself, find its usages across project source code. You most likely encounter Maven and IDEA plugins.

Please, notice that these APIs for embedding are still unstable and may change between versions.

WebAssembly

WebAssembly support is in experimental status. It may lack major features available in JavaScript backend. There's no documentation yet, and you should do many things by hands (like embedding generated wasm file into your page, importing JavaScript objects, etc). Look at samples/benchmark module. You should first examine pom.xml file to learn how to build wasm file from Java. Then you may want to examine index-teavm.html and index-teavm.js to learn how to embed WebAssembly into your web page.

License

TeaVM is distributed under Apache License 2.0. TeaVM does not rely on OpenJDK or code or other (L)GPL code. TeaVM has its own reimplementation of Java class library, which is either implemented from scratch or based on non-(L)GPL projects:

• Apache Harmony (Apache 2.0)
• Joda-Time (Apache 2.0)
• jzlib (BSD style license)

If you want to contribute code to implementation of Java class library, please make sure it's not based on OpenJDK or other code licensed under (L)GPL.

Feedback

More information is available at the official site: https://teavm.org.

Ask your questions by email: info@teavm.org. Also, you can report issues on a project's issue tracker.