1 files changed, 78 insertions, 0 deletions
diff --git a/deps/v8/test/js-perf-test/Strings/string-startswith.js b/deps/v8/test/js-perf-test/Strings/string-startswith.js
new file mode 100644
index 0000000000..4b0379b3a3
--- /dev/null
+++ b/deps/v8/test/js-perf-test/Strings/string-startswith.js
@@ -0,0 +1,78 @@
+// Copyright 2019 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+function createSuite(name, count, fn) {
+  new BenchmarkSuite(name, [count], [new Benchmark(name, true, false, 0, fn)]);
+}
+
+const inputs = [
+  'Lorem ipsum dolor sit amet, consectetur adipiscing elit.',
+  'Integer eu augue suscipit, accumsan ipsum nec, sagittis sem.',
+  'In vitae pellentesque dolor. Curabitur leo nunc, luctus vitae',
+  'risus eget, fermentum hendrerit justo.',
+  'hello'.repeat(1024),
+  'h',
+  ''
+];
+const firsts = ['I', 'Integer', 'Lorem', 'risus', 'hello'];
+
+function simpleHelper() {
+  let sum = 0;
+  for (const input of inputs) {
+    for (const first of firsts) {
+      sum += input.startsWith(first);
+    }
+  }
+  return sum;
+}
+
+function consInputHelper() {
+  let sum = 0;
+  for (const inputOne of inputs) {
+    for (const inputTwo of inputs) {
+      for (const first of firsts) {
+        // Skip if the length is too small for %ConstructConsString
+        if (inputOne.length + inputTwo.length < 13) break;
+        sum += %ConstructConsString(inputOne, inputTwo).startsWith(first);
+      }
+    }
+  }
+  return sum;
+}
+
+function consFirstHelper() {
+  let sum = 0;
+  for (const input of inputs) {
+    for (const firstOne of firsts) {
+      for (const firstTwo of firsts) {
+        // Skip if the length is too small for %ConstructConsString
+        if (firstOne.length + firstTwo.length < 13) break;
+        sum += input.startsWith(%ConstructConsString(firstOne, firstTwo));
+      }
+    }
+  }
+  return sum;
+}
+
+function doubleConsHelper() {
+  let sum = 0;
+  for (const inputOne of inputs) {
+    for (const inputTwo of inputs) {
+      for (const firstOne of firsts) {
+        for (const firstTwo of firsts) {
+          // Skip if the length is too small for %ConstructConsString
+          if (inputOne.length + inputTwo.length < 13 || firstOne.length + firstTwo.length) break;
+          sum += % ConstructConsString(inputOne, inputTwo).startsWith(
+            % ConstructConsString(firstOne, firstTwo)
+          );
+        }
+      }
+    }
+  }
+}
+
+createSuite('DirectStringsDirectSearch', 1000, simpleHelper);
+createSuite('ConsStringsDirectSearch', 1000, consInputHelper);
+createSuite('DirectStringsConsSearch', 1000, consFirstHelper);
+createSuite('ConsStringsConsSearch', 1000, doubleConsHelper);