feat: performance builtin support (#150)

Author: Guy Bedford

CMakeLists.txt

@@ -3,5 +3,6 @@ cmake_minimum_required(VERSION 3.27)
 include("StarlingMonkey/cmake/add_as_subproject.cmake")
 
 add_builtin(componentize::embedding SRC embedding/embedding.cpp)
+include_directories("StarlingMonkey")
 
 project(ComponentizeJS)

Makefile

@@ -27,7 +27,7 @@ lib/starlingmonkey_embedding.wasm: StarlingMonkey/cmake/* embedding/* StarlingMo
 	@cp build-release/starling-raw.wasm/starling-raw.wasm $@
 
 lib/starlingmonkey_embedding_weval.wasm: StarlingMonkey/cmake/* embedding/* StarlingMonkey/runtime/* StarlingMonkey/builtins/* StarlingMonkey/builtins/*/* StarlingMonkey/builtins/*/*/* StarlingMonkey/include/* | lib
-	cmake -B build-release-weval -DCMAKE_BUILD_TYPE=Release -DWEVAL=ON
+	cmake -B build-release-weval -DCMAKE_BUILD_TYPE=Release -DUSE_WASM_OPT=OFF -DWEVAL=ON
 	make -j16 -C build-release-weval
 	@cp build-release-weval/starling-raw.wasm/starling-raw.wasm $@
 

embedding/embedding.cpp

@@ -1,4 +1,5 @@
 #include "embedding.h"
+#include "builtins/web/performance.h"
 
 namespace builtins::web::console {
 
@@ -65,7 +66,8 @@ from_bigint64(JS::MutableHandleValue handle) {
   JS::BigInt *arg0 = handle.toBigInt();
   uint64_t arg0_uint64;
   if (!JS::detail::BigIntIsUint64(arg0, &arg0_uint64)) {
-    Runtime.engine->abort("Internal bindgen error in coreabi_from_bigint64 validation");
+    Runtime.engine->abort(
+        "Internal bindgen error in coreabi_from_bigint64 validation");
   }
   return arg0_uint64;
 }
@@ -148,6 +150,10 @@ __attribute__((export_name("call"))) uint32_t call(uint32_t fn_idx,
   if (Runtime.first_call) {
     js::ResetMathRandomSeed(Runtime.cx);
     Runtime.first_call = false;
+    if (Runtime.clocks) {
+      builtins::web::performance::Performance::timeOrigin.emplace(
+          std::chrono::high_resolution_clock::now());
+    }
   }
   if (Runtime.cur_fn_idx != -1) {
     LOG("(call) unexpected call state, post_call was not called after last "
@@ -350,6 +356,11 @@ componentize_initialize() {
     Runtime.debug = true;
   }
 
+  uint32_t feature_clocks = atoi(getenv("FEATURE_CLOCKS"));
+  if (feature_clocks) {
+    Runtime.clocks = true;
+  }
+
   __wizer_initialize();
   char env_name[100];
   LOG("(wizer) retrieve and generate the export bindings");

embedding/embedding.h

@@ -46,6 +46,8 @@ namespace componentize::embedding
     bool debug = false;
     bool first_call = true;
 
+    bool clocks = false;
+
     JSContext *cx;
 
     InitError init_err = InitError::OK;

src/componentize.js

@@ -173,6 +173,7 @@ export async function componentize(jsSource, witWorld, opts) {
     SOURCE_NAME: sourceName,
     IMPORT_WRAPPER_CNT: Object.keys(importWrappers).length.toString(),
     EXPORT_CNT: exports.length.toString(),
+    FEATURE_CLOCKS: features.includes('clocks') ? '1' : '',
   };
 
   for (const [idx, [export_name, expt]] of exports.entries()) {

test/builtins/performance-disabled.js

@@ -0,0 +1,19 @@
+import { ok, strictEqual } from 'node:assert';
+
+export const source = `
+  export function run () {
+    performance.now();
+  };
+`;
+
+export const disableFeatures = ['clocks'];
+
+export async function test (run) {
+  try {
+    const { stdout, stderr } = await run();
+    ok(false);
+  } catch {
+    // performance builtin just panics
+    // (yes we can and should do better...)
+  }
+}

test/builtins/performance.js

@@ -0,0 +1,28 @@
+import { ok, strictEqual } from 'node:assert';
+
+export const source = `
+  export function run () {
+    const start = performance.now();
+    let previous = 0, cur = 1;
+    for (let i = 1; i < 1000; i++) {
+      const tmp = cur;
+      cur = previous + cur;
+      previous = tmp;
+    }
+    const end = performance.now();
+    console.log('Calculated fib 1000: ' + cur);
+    console.error((end - start) + ' ms');
+  };
+`;
+
+export async function test (run) {
+  const { stdout, stderr } = await run();
+  strictEqual(stdout, 'Calculated fib 1000: 4.346655768693743e+208\n');
+
+  ok(stderr.includes(' ms'));
+  const time = Number(stderr.split(' ms')[0]);
+  // TODO: fix back to half a millisecond when Weval fix is added
+  if (time > 3) {
+    throw new Error('took more than half a millisecond - ' + time + ' ms');
+  }
+}