Difference between revisions of "WebAssembly/Compiler"

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(Using the compiler)
(WASI - The WebAssembly System Interface)
 
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== Instructions ==
 
== Instructions ==
=== Compiling the compiler ===
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 +
=== Prerequisites ===
 +
 
 +
The ''llvm-mc'' assembler and ''wasm-ld'' linker. These are the assembler and linker from the LLVM project.
 +
 
 +
LLVM 11.0 is known to work. Development was done, using the Fedora packages llvm-11.0.0-1.fc33.x86_64 and lld-11.0.0-1.fc33.x86_64. Initial tests on MacOS used llvm-11 installed with MacPorts (https://www.macports.org) and according symlinks in /opt/local/bin (wasm32-wasi-llvm-mc -> llvm-mc-mp-11 and wasm32-embedded-llvm-mc -> llvm-mc-mp-11).
 +
 
 +
=== Obtaining the compiler sources ===
 +
 
 +
The WebAssembly target was merged into FPC SVN trunk in r48955 on 2021-03-14.
  
 
Get the sources:
 
Get the sources:
  
  git clone https://github.com/skalogryz/freepascal fpc-wasm
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  svn checkout https://svn.freepascal.org/svn/fpc/trunk fpc-wasm
+
 
switch to correct branch:
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enter the directory:
 
  cd fpc-wasm
 
  cd fpc-wasm
git checkout webasm
 
  
compile:
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=== Supported targets ===
cd compiler
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==== WASI - The WebAssembly System Interface ====
====Using Lazarus====
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  open ppcwasm.lpi
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[https://wasi.dev/ WASI] is a modular system interface for WebAssembly. It allows creating portable and secure programs that can run in a sandboxed command-line environment. See the WASI website for more information.
hit the "compile" button.
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 +
To build the compiler for the WASI target:
 +
 
 +
make all OS_TARGET=wasi CPU_TARGET=wasm32 BINUTILSPREFIX= OPT="-O-" PP=fpc
  
=====Using command-line=====
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The following units have been ported for the WASI target:
fpc -dnoopt -dwasm -Fiwasm -Fuwasm -Fusystems -S2 pp.pas
 
  
the compiler can be renamed
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* system
mv pp ppwasm
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* objpas
or, on windows:
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* ctypes
mv pp.exe ppwasm.exe
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* strings
 +
* wasiapi - interface for the WASI API
  
=== Using the compiler ===
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Compiled WASI binaries work with wasmtime version 0.23.0 or in the browser by opening:
 +
 
 +
https://webassembly.sh/
 +
 
 +
and drag and dropping the .wasm binary directly into the browser window.
  
You need a system.pas unit. It can be found here:
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==== Embedded target ====
  
[https://github.com/skalogryz/wasm-demo wasm-demo]
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The [[TARGET_Embedded|Embedded target]] is primarily used for embedded systems, without an operating system. However, it also happens to be a perfect fit for creating WebAssembly modules that don't use any particular operating system-like API.
  
You'll also need the wasm tools:
+
make all OS_TARGET=embedded CPU_TARGET=wasm32 BINUTILSPREFIX= OPT="-O-" PP=fpc
  
[https://github.com/WebAssembly/wabt/releases wasm tools]
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=== Using the compiler ===
  
Extract the binaries and put them somewhere in your PATH.
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Hint: If your fpc.cfg has
 +
<pre>
 +
#IFDEF FPC_CROSSCOMPILING
 +
#IFDEF NEEDCROSSBINUTILS
 +
  -XP$FPCTARGET-
 +
#ENDIF
 +
#ENDIF
 +
</pre>
  
And you'll need some more wasm tools:
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Enclose it in '''#IFNDEF CPUWASM32''' :
 +
<pre>
 +
#IFDEF FPC_CROSSCOMPILING
 +
#IFDEF NEEDCROSSBINUTILS
 +
#ifndef cpuwasm32
 +
  -XP$FPCTARGET-
 +
#endif
 +
#ENDIF
 +
#ENDIF
 +
</pre>
  
[https://github.com/skalogryz/wasmbin]
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Otherwise, you have to create symlinks wasm32-wasi-llvm-mc to llvm-mc, and wasm32-wasi-wasm-ld to wasm-ld.
  
* Compile wasmtool.lpi
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==outdated: wasm-demo==
* Compile wasmld.lpi and rename wasmld to wasm-ld
 
  
Put wasmtool and wasm-ld somewhere in your PATH
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Note: this section is outdated.
  
==wasm-demo==
 
 
Wasm-demo is a Pascal WebAssembly demo project, ported Google's C WebAssembly example (https://codelabs.developers.google.com/codelabs/web-assembly-intro)
 
Wasm-demo is a Pascal WebAssembly demo project, ported Google's C WebAssembly example (https://codelabs.developers.google.com/codelabs/web-assembly-intro)
  

Latest revision as of 07:23, 19 March 2021

Instructions

Prerequisites

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

LLVM 11.0 is known to work. Development was done, using the Fedora packages llvm-11.0.0-1.fc33.x86_64 and lld-11.0.0-1.fc33.x86_64. Initial tests on MacOS used llvm-11 installed with MacPorts (https://www.macports.org) and according symlinks in /opt/local/bin (wasm32-wasi-llvm-mc -> llvm-mc-mp-11 and wasm32-embedded-llvm-mc -> llvm-mc-mp-11).

Obtaining the compiler sources

The WebAssembly target was merged into FPC SVN trunk in r48955 on 2021-03-14.

Get the sources:

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

enter the directory:

cd fpc-wasm

Supported targets

WASI - The WebAssembly System Interface

WASI is a modular system interface for WebAssembly. It allows creating portable and secure programs that can run in a sandboxed command-line environment. See the WASI website for more information.

To build the compiler for the WASI target:

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

The following units have been ported for the WASI target:

  • system
  • objpas
  • ctypes
  • strings
  • wasiapi - interface for the WASI API

Compiled WASI binaries work with wasmtime version 0.23.0 or in the browser by opening:

https://webassembly.sh/

and drag and dropping the .wasm binary directly into the browser window.

Embedded target

The Embedded target is primarily used for embedded systems, without an operating system. However, it also happens to be a perfect fit for creating WebAssembly modules that don't use any particular operating system-like API.

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

Using the compiler

Hint: If your fpc.cfg has

#IFDEF FPC_CROSSCOMPILING
#IFDEF NEEDCROSSBINUTILS
  -XP$FPCTARGET-
#ENDIF
#ENDIF

Enclose it in #IFNDEF CPUWASM32 :

#IFDEF FPC_CROSSCOMPILING
#IFDEF NEEDCROSSBINUTILS
#ifndef cpuwasm32
  -XP$FPCTARGET-
#endif
#ENDIF
#ENDIF

Otherwise, you have to create symlinks wasm32-wasi-llvm-mc to llvm-mc, and wasm32-wasi-wasm-ld to wasm-ld.

outdated: wasm-demo

Note: this section is outdated.

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:

main.html
main.js
main.wat

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