Write d8 benchmark using the baseline compiler

codecs/rotate/benchmark.js

@@ -0,0 +1,37 @@
+// THIS IS NOT A NODE SCRIPT
+// This is a d8 script. Please install jsvu[1] and install v8.
+// Then run `npm run --silent benchmark`.
+// [1]: https://github.com/GoogleChromeLabs/jsvu
+async function init() {
+  //  Adjustable constants.
+  const imageDimensions = 4096;
+  const iterations = new Array(100);
+
+  // Constants. Don’t change.
+  const imageByteSize = imageDimensions * imageDimensions * 4;
+  const wasmPageSize = 64 * 1024;
+
+  const buffer = readbuffer("rotate.wasm");
+  const {instance} = await WebAssembly.instantiate(buffer);
+
+  const pagesAvailable = Math.floor(instance.exports.memory.buffer.byteLength / wasmPageSize);
+  const pagesNeeded = Math.floor((imageByteSize * 2 + 4) / wasmPageSize) + 1;
+  const additionalPagesNeeded = pagesNeeded - pagesAvailable;
+  if(additionalPagesNeeded > 0) {
+    instance.exports.memory.grow(additionalPagesNeeded)
+  }
+
+  for(let i = 0; i < 100; i++) {
+    const start = Date.now();
+    instance.exports.rotate(imageDimensions, imageDimensions, 90);
+    iterations[i] = Date.now() - start;
+  }
+  const average = iterations.reduce((sum, c) => sum + c) / iterations.length;
+  const stddev = Math.sqrt(iterations
+    .map(i => Math.pow(i - average, 2))
+    .reduce((sum, c) => sum + c) / iterations.length);
+  print(`n = ${iterations.length}`);
+  print(`Average: ${average}`)
+  print(`StdDev: ${stddev}`);
+}
+init().catch(e => console.error(e.stack));

codecs/rotate/package.json

@@ -2,6 +2,7 @@
   "name": "rotate",
   "scripts": {
     "build:image": "docker build -t squoosh-rotate .",
-    "build": "docker run --rm -v $(pwd):/src squoosh-rotate ./build.sh"
+    "build": "docker run --rm -v $(pwd):/src squoosh-rotate ./build.sh",
+    "benchmark": "v8 --liftoff --no-wasm-tier-up --no-opt ./benchmark.js"
   }
 }