Source and licences

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Icarus Verilog 12.0

The simulator files ivlpp.wasm, ivl.wasm and vvp.wasm are Icarus Verilog version 12.0 by Stephen Williams and contributors, compiled to WebAssembly with the WASI SDK 25. Icarus Verilog is free software under the GNU General Public License, version 2 or later.

Original source: github.com/steveicarus/iverilog, tag v12_0
Changes made for the browser build: icarus-wasm.patch (removes subprocess calls and resource-usage statistics) and static_dl.c (links the VPI modules and code generator into the same binary instead of loading them at run time)
Full licence text: GNU GPL v2

To rebuild: configure Icarus with the WASI SDK as the C and C++ compiler (--host=wasm32-unknown-none, with the WASI emulated signal, process-clock, mman, getpid and pthread libraries), apply the patch, compile static_dl.c, and link ivl with the tgt-vvp objects and the system, v2005_math, va_math and v2009 VPI objects, renaming each module's vlog_startup_routines (and the code generator's target_design and target_query) to the names in static_dl.c. Link vvp the same way with the VPI objects.

browser_wasi_shim

WASI runtime for the browser by bjorn3, under the MIT or Apache-2.0 licence. MIT licence text.

CodeMirror 5

Code editor by Marijn Haverbeke and contributors, MIT licence, loaded from cdnjs.