Difference between revisions of "WebAssembly/Compiler"

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=== Using the compiler ===
=== Using the compiler ===
You need a system.pas unit. It can be found here:
[https://github.com/skalogryz/wasm-demo wasm-demo]
You'll also need the wasm bin tools:
[https://github.com/WebAssembly/wabt/releases wasm bin tools]
Extract the binaries and put them somewhere in your PATH.
You'll also need the wasmtool:
[https://github.com/skalogryz/wasmbin wasmtool]
* Compile wasmtool.lpi
Put wasmtool somewhere in your PATH
And finally you need ''wasm-ld'' (don't confuse it with ''wasmld'').
* Download the [http://releases.llvm.org/download.html llvm-9 release], and put the '''bin/ldd''' as '''wasmld''' in your PATH.
Hint: If your fpc.cfg has
Hint: If your fpc.cfg has

Revision as of 06:08, 31 January 2021



The llvm-mc assembler and wasm-ld linker. These are the assembler and linker from the LLVM project.

Compiling the compiler

Get the sources:

svn checkout https://svn.freepascal.org/svn/fpc/branches/wasm/ fpc-wasm

enter the directory:

cd fpc-wasm

WASI target

make all OS_TARGET=wasi CPU_TARGET=wasm32 BINUTILSPREFIX= OPT="-O-" PP=fpc

Embedded target

make all OS_TARGET=embedded CPU_TARGET=wasm32 BINUTILSPREFIX= OPT="-O-" PP=fpc

Using the compiler

Hint: If your fpc.cfg has


Enclose it in #IFNDEF CPUWASM :

#ifndef cpuwasm

Otherwise, you have to create symlinks wasm-wasm-wasmld to wasmld, and wasm-wasm-wasmtool to wasmtool.


Wasm-demo is a Pascal WebAssembly demo project, ported Google's C WebAssembly example (https://codelabs.developers.google.com/codelabs/web-assembly-intro)

You follow these steps in order to get the demo project working:

1. Get the project sources: https://github.com/skalogryz/wasm-demo

Using in webassembly.studio

2. Run the wasm compiler against lyff.pas, but request the assembler file to be kept

 pp -a lyff.pas

Webassembly.studio accepts the assembler file and would compile it on the server side.

3. open up https://webassembly.studio and select "Create empty Wat Project". The project will consist of:


All files of the project can be edited through the web interface.

4. Copy and paste the contents of the following files:

(compiled) lyff.wat to main.wat.
wasm-demo\webassembly.studio\main.html to main.html
wasm-demo\webassembly.studio\main.js to main.js

Note: every time you copy and paste, don't forget to press "SAVE" button (on the right side of the web interface)

5. once all files are update, hit "Build and Run"

See Also