0xmozak · supragya · Jun 19, 2024
diff --git a/.gitignore b/.gitignore
@@ -4,6 +4,7 @@ debug/
 target/
 target-tarpaulin/
 target-custom/
+venv/
 
 # These are backup files generated by rustfmt
 **/*.rs.bk

diff --git a/Cargo.toml b/Cargo.toml
@@ -15,7 +15,7 @@
 # the part of this workspace
 
 [workspace]
-exclude = ["sdk"]
+exclude = ["sdk", "ws2riscvtest"]
 members = [
   "circuits",
   "cli",
@@ -32,6 +32,7 @@ resolver = "2"
 [profile.dev]
 lto = "thin"
 # We are running our tests with optimizations turned on to make them faster.
+
 # Please turn optimizations off, when you want accurate stack traces for debugging.
 opt-level = 2
 

diff --git a/ws2riscvtest/Cargo.toml b/ws2riscvtest/Cargo.toml
@@ -0,0 +1,10 @@
+[package]
+edition = "2021"
+name = "ws2riscvtest"
+version = "0.1.0"
+
+[lib]
+crate-type = ["cdylib"]
+
+[dependencies]
+wasm-bindgen = "0.2"
diff --git a/ws2riscvtest/README.md b/ws2riscvtest/README.md
@@ -0,0 +1,27 @@
+# What
+This directory aims at testing if we can convert a WASM binary to RISC-V target and make it run well on `mozak-vm`. We simulate a naive implementation of Fibonacci for this.
+
+## Building and testing a WASM module
+We need `wasm-pack` via
+```
+cargo install wasm-pack
+```
+
+Inside the directory `wasmtest`, we build a WASM module via:
+```
+wasm-pack build --target web
+```
+This builds binary for the target `wasm-unknown-unknown`
+
+This would build artifacts accessible in the directory `./pkg`. Most importantly, these files would be generated:
+1. `pkg/ws2riscvtest_bg.wasm`, the WASM binary file.
+2. `pkg/ws2riscvtest.js`, the JS file required to run WASM code in browser
+
+Run a dummy testing server (on port 8000 by default) via:
+```
+python3 -m http.server
+```
+and load up `http://localhost:8000/` in the browser. The correct run should output:
+```
+WASM TESTER! Function result: 34
+```
diff --git a/ws2riscvtest/index.html b/ws2riscvtest/index.html
@@ -0,0 +1,9 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <meta charset="UTF-8" />
+    <title>WASM Tester</title>
+    <script type="module" src="index.js"></script>
+  </head>
+  <body></body>
+</html>
diff --git a/ws2riscvtest/index.js b/ws2riscvtest/index.js
@@ -0,0 +1,15 @@
+// Import our outputted wasm ES6 module
+// Which, export default's, an initialization function
+import init from "./pkg/ws2riscvtest.js";
+
+const runWasm = async () => {
+  // Instantiate our wasm module
+  const module = await init("./pkg/ws2riscvtest_bg.wasm");
+
+  // Call the function exported from wasm, save the result
+  const funcResult = module.fibonacci(BigInt("8"));
+
+  // Set the result onto the body
+  document.body.textContent = `WASM TESTER! Function result: ${funcResult}`;
+};
+runWasm();
diff --git a/ws2riscvtest/src/lib.rs b/ws2riscvtest/src/lib.rs
@@ -0,0 +1,14 @@
+// The wasm-pack uses wasm-bindgen to build and generate JavaScript binding file.
+// Import the wasm-bindgen crate.
+use wasm_bindgen::prelude::*;
+
+// Our fibonacci function
+// wasm-pack requires "exported" functions
+// to include #[wasm_bindgen]
+#[wasm_bindgen]
+pub fn fibonacci(a: u64) -> u64 {
+    if a == 0 || a == 1 {
+        return 1;
+    }
+    return fibonacci(a-1) + fibonacci(a - 2);
+}