test: fix test-hash-seed for new V8 versions

The test relied on V8 not optimizing functions that use `set.has()`. Force V8 to not optimize it now that TurboFan knows about this method. PR-URL: #44741 Reviewed-By: Ben Noordhuis <[email protected]> Reviewed-By: Jiawen Geng <[email protected]> Reviewed-By: James M Snell <[email protected]>
nodejs · Oct 11, 2022 · 1acf033 · 1acf033
1 parent c9602ce
commit 1acf033
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Showing 2 changed files with 11 additions and 4 deletions.
diff --git a/test/fixtures/guess-hash-seed.js b/test/fixtures/guess-hash-seed.js
@@ -67,9 +67,6 @@ function hash_to_bucket(hash, numBuckets) {
 function time_set_lookup(set, value) {
   const t1 = process.hrtime();
   for (let i = 0; i < 100; i++) {
-    // annoyingly, SetHas() is JS code and therefore potentially optimizable.
-    // However, SetHas() looks up the table using native code, and it seems like
-    // that's sufficient to prevent the optimizer from doing anything?
     set.has(value);
   }
   const t = process.hrtime(t1);
@@ -78,6 +75,9 @@ function time_set_lookup(set, value) {
   return secs * 1e9 + nanos;
 }
 
+// Prevent optimization of SetHas().
+%NeverOptimizeFunction(time_set_lookup);
+
 // Set with 256 buckets; bucket 0 full, others empty
 const tester_set_buckets = 256;
 const tester_set = new Set();

diff --git a/test/pummel/test-hash-seed.js b/test/pummel/test-hash-seed.js
@@ -24,7 +24,14 @@ const requiredCallback = common.mustCall((results) => {
   assert.strictEqual(seeds.length, kRepetitions);
 });
 
-const generateSeed = () => execFilePromise(process.execPath, [targetScript]);
+function generateSeed() {
+  return execFilePromise(process.execPath, [
+    // Needed for %NeverOptimizeFunction.
+    '--allow-natives-syntax',
+    targetScript,
+  ]);
+}
+
 const subprocesses = [...new Array(kRepetitions)].map(generateSeed);
 
 Promise.all(subprocesses)