From a93262428fbb89591faafceb82b21d608a06534c Mon Sep 17 00:00:00 2001
From: Rick Waldron <waldron.rick@gmail.com>
Date: Tue, 26 Jun 2018 13:22:30 -0400
Subject: [PATCH] Atomics: improvements to wake-*.js tests

---
 .../Atomics/wake/bigint/wake-all-on-loc.js    | 20 ++---
 .../built-ins/Atomics/wake/wake-all-on-loc.js | 24 ++---
 test/built-ins/Atomics/wake/wake-all.js       | 18 ++--
 .../Atomics/wake/wake-in-order-one-time.js    | 87 +++++++++++++++++++
 test/built-ins/Atomics/wake/wake-in-order.js  | 26 ++++--
 test/built-ins/Atomics/wake/wake-nan.js       |  9 +-
 test/built-ins/Atomics/wake/wake-one.js       | 12 +--
 test/built-ins/Atomics/wake/wake-two.js       | 19 ++--
 test/built-ins/Atomics/wake/wake-zero.js      | 54 +++++-------
 9 files changed, 181 insertions(+), 88 deletions(-)
 create mode 100644 test/built-ins/Atomics/wake/wake-in-order-one-time.js

diff --git a/test/built-ins/Atomics/wake/bigint/wake-all-on-loc.js b/test/built-ins/Atomics/wake/bigint/wake-all-on-loc.js
index 679be97e7f..a6efe40575 100644
--- a/test/built-ins/Atomics/wake/bigint/wake-all-on-loc.js
+++ b/test/built-ins/Atomics/wake/bigint/wake-all-on-loc.js
@@ -10,18 +10,18 @@ includes: [atomicsHelper.js]
 features: [Atomics, BigInt, SharedArrayBuffer, TypedArray]
 ---*/
 
-const WAKEUP = 0;                 // Waiters on this will be woken
-const DUMMY = 1;                  // Waiters on this will not be woken
+const WAIT_INDEX = 0;             // Waiters on this will be woken
+const WAIT_FAKE = 1;              // Waiters on this will not be woken
 const RUNNING = 2;                // Accounting of live agents
-const NUMELEM = 3;
 const NUMAGENT = 3;
+const BUFFER_SIZE = 4;
 
 for (var i = 0; i < NUMAGENT; i++) {
   $262.agent.start(`
     $262.agent.receiveBroadcast(function(sab) {
       const i64a = new BigInt64Array(sab);
       Atomics.add(i64a, ${RUNNING}, 1);
-      $262.agent.report("A " + Atomics.wait(i64a, ${WAKEUP}, 0));
+      $262.agent.report("A " + Atomics.wait(i64a, ${WAIT_INDEX}, 0));
       $262.agent.leaving();
     });
   `);
@@ -32,28 +32,28 @@ $262.agent.start(`
     const i64a = new BigInt64Array(sab);
     Atomics.add(i64a, ${RUNNING}, 1);
     // This will always time out.
-    $262.agent.report("B " + Atomics.wait(i64a, ${DUMMY}, 0, 10));
+    $262.agent.report("B " + Atomics.wait(i64a, ${WAIT_FAKE}, 0, 10));
     $262.agent.leaving();
   });
 `);
 
 const i64a = new BigInt64Array(
-  new SharedArrayBuffer(NUMELEM * BigInt64Array.BYTES_PER_ELEMENT)
+  new SharedArrayBuffer(BigInt64Array.BYTES_PER_ELEMENT * BUFFER_SIZE)
 );
 $262.agent.broadcast(i64a.buffer);
 
 // Wait for agents to be running.
-waitUntil(i64a, RUNNING, NUMAGENT + 1);
+waitUntil(i64a, RUNNING, BUFFER_SIZE);
 
 // Then wait some more to give the agents a fair chance to wait.  If we don't,
 // we risk sending the wakeup before agents are sleeping, and we hang.
 $262.agent.sleep(50);
 
-// Wake all waiting on WAKEUP, should be 3 always, they won't time out.
+// Wake all waiting on WAIT_INDEX, should be 3 always, they won't time out.
 assert.sameValue(
-  Atomics.wake(i64a, WAKEUP),
+  Atomics.wake(i64a, WAIT_INDEX),
   NUMAGENT,
-  'Atomics.wake(i64a, WAKEUP) equals the value of `NUMAGENT` (3)'
+  'Atomics.wake(i64a, WAIT_INDEX) equals the value of `NUMAGENT` (3)'
 );
 
 var rs = [];
diff --git a/test/built-ins/Atomics/wake/wake-all-on-loc.js b/test/built-ins/Atomics/wake/wake-all-on-loc.js
index e094e8526f..cda0d96a94 100644
--- a/test/built-ins/Atomics/wake/wake-all-on-loc.js
+++ b/test/built-ins/Atomics/wake/wake-all-on-loc.js
@@ -10,19 +10,18 @@ includes: [atomicsHelper.js]
 features: [Atomics, SharedArrayBuffer, TypedArray]
 ---*/
 
-const WAKEUP = 0;                 // Waiters on this will be woken
-const DUMMY = 1;                  // Waiters on this will not be woken
+const WAIT_INDEX = 0;             // Waiters on this will be woken
+const WAIT_FAKE = 1;              // Waiters on this will not be woken
 const RUNNING = 2;                // Accounting of live agents
-const NUMELEM = 3;
-
 const NUMAGENT = 3;
+const BUFFER_SIZE = 4;
 
-for (var i=0; i < NUMAGENT; i++) {
+for (var i = 0; i < NUMAGENT; i++) {
   $262.agent.start(`
     $262.agent.receiveBroadcast(function(sab) {
       const i32a = new Int32Array(sab);
       Atomics.add(i32a, ${RUNNING}, 1);
-      $262.agent.report("A " + Atomics.wait(i32a, ${WAKEUP}, 0));
+      $262.agent.report("A " + Atomics.wait(i32a, ${WAIT_INDEX}, 0));
       $262.agent.leaving();
     });
   `);
@@ -33,28 +32,29 @@ $262.agent.start(`
     const i32a = new Int32Array(sab);
     Atomics.add(i32a, ${RUNNING}, 1);
     // This will always time out.
-    $262.agent.report("B " + Atomics.wait(i32a, ${DUMMY}, 0, 10));
+    $262.agent.report("B " + Atomics.wait(i32a, ${WAIT_FAKE}, 0, 10));
     $262.agent.leaving();
   });
 `);
 
 const i32a = new Int32Array(
-  new SharedArrayBuffer(NUMELEM * Int32Array.BYTES_PER_ELEMENT)
+  new SharedArrayBuffer(Int32Array.BYTES_PER_ELEMENT * BUFFER_SIZE)
 );
+
 $262.agent.broadcast(i32a.buffer);
 
 // Wait for agents to be running.
-waitUntil(i32a, RUNNING, NUMAGENT + 1);
+waitUntil(i32a, RUNNING, BUFFER_SIZE);
 
 // Then wait some more to give the agents a fair chance to wait.  If we don't,
 // we risk sending the wakeup before agents are sleeping, and we hang.
 $262.agent.sleep(50);
 
-// Wake all waiting on WAKEUP, should be 3 always, they won't time out.
+// Wake all waiting on WAIT_INDEX, should be 3 always, they won't time out.
 assert.sameValue(
-  Atomics.wake(i32a, WAKEUP),
+  Atomics.wake(i32a, WAIT_INDEX),
   NUMAGENT,
-  'Atomics.wake(i32a, WAKEUP) equals the value of `NUMAGENT` (3)'
+  'Atomics.wake(i32a, WAIT_INDEX) equals the value of `NUMAGENT` (3)'
 );
 
 const rs = [];
diff --git a/test/built-ins/Atomics/wake/wake-all.js b/test/built-ins/Atomics/wake/wake-all.js
index 1d6a3de1dd..0da7909479 100644
--- a/test/built-ins/Atomics/wake/wake-all.js
+++ b/test/built-ins/Atomics/wake/wake-all.js
@@ -9,18 +9,18 @@ includes: [atomicsHelper.js]
 features: [Atomics, SharedArrayBuffer, TypedArray]
 ---*/
 
-const WAKEUP = 0;                 // Waiters on this will be woken
-const DUMMY = 1;                  // Waiters on this will not be woken
+const WAIT_INDEX = 0;             // Waiters on this will be woken
+const WAIT_FAKE = 1;              // Waiters on this will not be woken
 const RUNNING = 2;                // Accounting of live agents
-const NUMELEM = 3;
 const NUMAGENT = 3;
+const BUFFER_SIZE = 4;
 
 for (var i = 0; i < NUMAGENT; i++) {
   $262.agent.start(`
     $262.agent.receiveBroadcast(function(sab) {
       const i32a = new Int32Array(sab);
       Atomics.add(i32a, ${RUNNING}, 1);
-      $262.agent.report("A " + Atomics.wait(i32a, ${WAKEUP}, 0));
+      $262.agent.report("A " + Atomics.wait(i32a, ${WAIT_INDEX}, 0));
       $262.agent.leaving();
     });
   `);
@@ -31,13 +31,13 @@ $262.agent.start(`
     const i32a = new Int32Array(sab);
     Atomics.add(i32a, ${RUNNING}, 1);
     // This will always time out.
-    $262.agent.report("B " + Atomics.wait(i32a, ${DUMMY}, 0, 10));
+    $262.agent.report("B " + Atomics.wait(i32a, ${WAIT_FAKE}, 0, 10));
     $262.agent.leaving();
   });
 `);
 
 const i32a = new Int32Array(
-  new SharedArrayBuffer(NUMELEM * Int32Array.BYTES_PER_ELEMENT)
+  new SharedArrayBuffer(Int32Array.BYTES_PER_ELEMENT * BUFFER_SIZE)
 );
 
 $262.agent.broadcast(i32a.buffer);
@@ -49,11 +49,11 @@ waitUntil(i32a, RUNNING, NUMAGENT + 1);
 // we risk sending the wakeup before agents are sleeping, and we hang.
 $262.agent.sleep(50);
 
-// Wake all waiting on WAKEUP, should be 3 always, they won't time out.
+// Wake all waiting on WAIT_INDEX, should be 3 always, they won't time out.
 assert.sameValue(
-  Atomics.wake(i32a, WAKEUP),
+  Atomics.wake(i32a, WAIT_INDEX),
   NUMAGENT,
-  'Atomics.wake(i32a, WAKEUP) equals the value of `NUMAGENT` (3)'
+  'Atomics.wake(i32a, WAIT_INDEX) equals the value of `NUMAGENT` (3)'
 );
 
 const rs = [];
diff --git a/test/built-ins/Atomics/wake/wake-in-order-one-time.js b/test/built-ins/Atomics/wake/wake-in-order-one-time.js
new file mode 100644
index 0000000000..1ab2223be2
--- /dev/null
+++ b/test/built-ins/Atomics/wake/wake-in-order-one-time.js
@@ -0,0 +1,87 @@
+// Copyright (C) 2017 Mozilla Corporation.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-atomics.wake
+description: >
+  Test that Atomics.wake wakes agents in the order they are waiting.
+includes: [atomicsHelper.js]
+features: [Atomics, SharedArrayBuffer, TypedArray]
+---*/
+
+const NUMAGENT = 3;
+const WAIT_INDEX = 0;             // Waiters on this will be woken
+const SPIN = 1;                   // Worker i (zero-based) spins on location SPIN+i
+const RUNNING = SPIN + NUMAGENT;  // Accounting of live agents
+const BUFFER_SIZE = RUNNING + 1;
+
+// Create workers and start them all spinning.  We set atomic slots to make
+// them go into a wait, thus controlling the waiting order.  Then we wake them
+// one by one and observe the wakeup order.
+
+for (var i = 0; i < NUMAGENT; i++) {
+  $262.agent.start(`
+    $262.agent.receiveBroadcast(function(sab) {
+      const i32a = new Int32Array(sab);
+      Atomics.add(i32a, ${RUNNING}, 1);
+      while (Atomics.load(i32a, ${SPIN + i}) === 0) {
+        /* nothing */
+      }
+      $262.agent.report(${i});
+      Atomics.wait(i32a, ${WAIT_INDEX}, 0);
+      $262.agent.report(${i});
+      $262.agent.leaving();
+    });
+  `);
+}
+
+const i32a = new Int32Array(
+  new SharedArrayBuffer(Int32Array.BYTES_PER_ELEMENT * BUFFER_SIZE)
+);
+
+$262.agent.broadcast(i32a.buffer);
+
+// Wait for agents to be running.
+waitUntil(i32a, RUNNING, NUMAGENT);
+
+// Sleep to allow the agents a fair chance to wait. If we don't,
+// we risk sending the wakeup before agents are sleeping, and we hang.
+$262.agent.sleep(50);
+
+var waiterlist = [];
+assert.sameValue(Atomics.store(i32a, SPIN + 0, 1), 1);
+waiterlist.push(getReport());
+
+assert.sameValue(Atomics.store(i32a, SPIN + 1, 1), 1);
+waiterlist.push(getReport());
+
+assert.sameValue(Atomics.store(i32a, SPIN + 2, 1), 1);
+waiterlist.push(getReport());
+
+var notified = [];
+assert.sameValue(
+  Atomics.wake(i32a, WAIT_INDEX, 1),
+  1,
+  `Notification #0: on WAIT_INDEX (0) of i32a must notify 1 waiter.`
+);
+notified.push(getReport());
+
+assert.sameValue(
+  Atomics.wake(i32a, WAIT_INDEX, 1),
+  1,
+  `Notification #1: on WAIT_INDEX (0) of i32a must notify 1 waiter.`
+);
+notified.push(getReport());
+
+assert.sameValue(
+  Atomics.wake(i32a, WAIT_INDEX, 1),
+  1,
+  `Notification #2: on WAIT_INDEX (0) of i32a must notify 1 waiter.`
+);
+notified.push(getReport());
+
+assert.sameValue(
+  notified.join(''),
+  waiterlist.join(''),
+  `notified and waiterlist order do not match.`
+);
diff --git a/test/built-ins/Atomics/wake/wake-in-order.js b/test/built-ins/Atomics/wake/wake-in-order.js
index 0b81dda43f..25df57db54 100644
--- a/test/built-ins/Atomics/wake/wake-in-order.js
+++ b/test/built-ins/Atomics/wake/wake-in-order.js
@@ -10,10 +10,10 @@ features: [Atomics, SharedArrayBuffer, TypedArray]
 ---*/
 
 const NUMAGENT = 3;
-const WAKEUP = 0;                 // Waiters on this will be woken
+const WAIT_INDEX = 0;             // Waiters on this will be woken
 const SPIN = 1;                   // Worker i (zero-based) spins on location SPIN+i
 const RUNNING = SPIN + NUMAGENT;  // Accounting of live agents
-const NUMELEM = RUNNING + 1;
+const BUFFER_SIZE = RUNNING + 1;
 
 // Create workers and start them all spinning.  We set atomic slots to make
 // them go into a wait, thus controlling the waiting order.  Then we wake them
@@ -29,7 +29,7 @@ for (var attempt = 0; attempt < 10; attempt++) {
           /* nothing */
         }
         $262.agent.report(${i});
-        Atomics.wait(i32a, ${WAKEUP}, 0);
+        Atomics.wait(i32a, ${WAIT_INDEX}, 0);
         $262.agent.report(${i});
         $262.agent.leaving();
       });
@@ -37,7 +37,7 @@ for (var attempt = 0; attempt < 10; attempt++) {
   }
 
   const i32a = new Int32Array(
-    new SharedArrayBuffer(NUMELEM * Int32Array.BYTES_PER_ELEMENT)
+    new SharedArrayBuffer(Int32Array.BYTES_PER_ELEMENT * BUFFER_SIZE)
   );
 
   $262.agent.broadcast(i32a.buffer);
@@ -60,13 +60,25 @@ for (var attempt = 0; attempt < 10; attempt++) {
   waiterlist.push(getReport());
 
   var notified = [];
-  assert.sameValue(Atomics.wake(i32a, WAKEUP, 1), 1);
+  assert.sameValue(
+    Atomics.wake(i32a, WAIT_INDEX, 1),
+    1,
+    `Attempt #${attempt}, Notification #0: on WAIT_INDEX (0) of i32a must notify 1 waiter.`
+  );
   notified.push(getReport());
 
-  assert.sameValue(Atomics.wake(i32a, WAKEUP, 1), 1);
+  assert.sameValue(
+    Atomics.wake(i32a, WAIT_INDEX, 1),
+    1,
+    `Attempt #${attempt}, Notification #1: on WAIT_INDEX (0) of i32a must notify 1 waiter.`
+  );
   notified.push(getReport());
 
-  assert.sameValue(Atomics.wake(i32a, WAKEUP, 1), 1);
+  assert.sameValue(
+    Atomics.wake(i32a, WAIT_INDEX, 1),
+    1,
+    `Attempt #${attempt}, Notification #2: on WAIT_INDEX (0) of i32a must notify 1 waiter.`
+  );
   notified.push(getReport());
 
   assert.sameValue(
diff --git a/test/built-ins/Atomics/wake/wake-nan.js b/test/built-ins/Atomics/wake/wake-nan.js
index 1c9a99dea0..972853e1ef 100644
--- a/test/built-ins/Atomics/wake/wake-nan.js
+++ b/test/built-ins/Atomics/wake/wake-nan.js
@@ -12,7 +12,7 @@ features: [ArrayBuffer, DataView, let, arrow-function, for-of, Atomics, BigInt,
 $262.agent.start(`
   $262.agent.receiveBroadcast(function(sab) {
     const i32a = new Int32Array(sab);
-    $262.agent.report(Atomics.wait(i32a, 0, 0, 1000)); // We will timeout eventually
+    $262.agent.report(Atomics.wait(i32a, 0, 0, 200)); // We will timeout eventually
     $262.agent.leaving();
   });
 `);
@@ -22,6 +22,9 @@ const i32a = new Int32Array(
 );
 
 $262.agent.broadcast(i32a.buffer);
-$262.agent.sleep(500); // Give the agent a chance to wait
-assert.sameValue(Atomics.wake(i32a, 0, NaN), 0, 'Atomics.wake(i32a, 0, NaN) returns 0'); // Don't actually wake it
+$262.agent.sleep(10); // Give the agent a chance to wait
+assert.sameValue(Atomics.wake(i32a, 0, NaN), 0, 'Atomics.wake(i32a, 0, NaN) returns 0, and will not actually notify any waiters.');
+
+// Sleep past the timeout
+$262.agent.sleep(300);
 assert.sameValue(getReport(), 'timed-out', 'getReport() returns "timed-out"');
diff --git a/test/built-ins/Atomics/wake/wake-one.js b/test/built-ins/Atomics/wake/wake-one.js
index 11b74ce861..a4fba02930 100644
--- a/test/built-ins/Atomics/wake/wake-one.js
+++ b/test/built-ins/Atomics/wake/wake-one.js
@@ -9,11 +9,11 @@ includes: [atomicsHelper.js]
 features: [Atomics, SharedArrayBuffer, TypedArray]
 ---*/
 
-const NUMAGENT = 3;
-const WAKEUP = 0;                 // Agents wait here
+const WAIT_INDEX = 0;             // Agents wait here
 const RUNNING = 1;                // Accounting of live agents here
-const NUMELEM = 2;
 const WAKECOUNT = 1;
+const NUMAGENT = 3;
+const BUFFER_SIZE = 4;
 
 for (var i = 0; i < NUMAGENT; i++ ) {
   $262.agent.start(`
@@ -21,14 +21,14 @@ for (var i = 0; i < NUMAGENT; i++ ) {
       const i32a = new Int32Array(sab);
       Atomics.add(i32a, ${RUNNING}, 1);
       // Waiters that are not woken will time out eventually.
-      $262.agent.report(Atomics.wait(i32a, ${WAKEUP}, 0, 2000));
+      $262.agent.report(Atomics.wait(i32a, ${WAIT_INDEX}, 0, 2000));
       $262.agent.leaving();
     });
   `);
 }
 
 const i32a = new Int32Array(
-  new SharedArrayBuffer(NUMELEM * Int32Array.BYTES_PER_ELEMENT)
+  new SharedArrayBuffer(Int32Array.BYTES_PER_ELEMENT * BUFFER_SIZE)
 );
 
 $262.agent.broadcast(i32a.buffer);
@@ -38,7 +38,7 @@ waitUntil(i32a, RUNNING, NUMAGENT);
 
 // Then wait some more to give the agents a fair chance to wait.  If we don't,
 // we risk sending the wakeup before agents are sleeping, and we hang.
-$262.agent.sleep(50);
+$262.agent.sleep(10);
 
 // There's a slight risk we'll fail to wake the desired count, if the preceding
 // sleep() took much longer than anticipated and workers have started timing
diff --git a/test/built-ins/Atomics/wake/wake-two.js b/test/built-ins/Atomics/wake/wake-two.js
index 6829f8f1d2..5cc398816f 100644
--- a/test/built-ins/Atomics/wake/wake-two.js
+++ b/test/built-ins/Atomics/wake/wake-two.js
@@ -10,11 +10,11 @@ features: [Atomics, SharedArrayBuffer, TypedArray]
 ---*/
 
 
-var NUMAGENT = 3;
-var WAKEUP = 0;                 // Agents wait here
-var RUNNING = 1;                // Accounting of live agents here
-var NUMELEM = 2;
-var WAKECOUNT = 2;
+const WAIT_INDEX = 0;             // Agents wait here
+const RUNNING = 1;                // Accounting of live agents here
+const WAKECOUNT = 2;
+const NUMAGENT = 3;
+const BUFFER_SIZE = 4;
 
 for (var i = 0; i < NUMAGENT; i++ ) {
   $262.agent.start(`
@@ -22,14 +22,14 @@ for (var i = 0; i < NUMAGENT; i++ ) {
       const i32a = new Int32Array(sab);
       Atomics.add(i32a, ${RUNNING}, 1);
       // Waiters that are not woken will time out eventually.
-      $262.agent.report(Atomics.wait(i32a, ${WAKEUP}, 0, 2000));
+      $262.agent.report(Atomics.wait(i32a, ${WAIT_INDEX}, 0, 200));
       $262.agent.leaving();
     })
   `);
 }
 
 const i32a = new Int32Array(
-  new SharedArrayBuffer(Int32Array.BYTES_PER_ELEMENT * 4)
+  new SharedArrayBuffer(Int32Array.BYTES_PER_ELEMENT * BUFFER_SIZE)
 );
 
 $262.agent.broadcast(i32a.buffer);
@@ -39,7 +39,7 @@ waitUntil(i32a, RUNNING, NUMAGENT);
 
 // Then wait some more to give the agents a fair chance to wait.  If we don't,
 // we risk sending the wakeup before agents are sleeping, and we hang.
-$262.agent.sleep(500);
+$262.agent.sleep(10);
 
 // There's a slight risk we'll fail to wake the desired count, if the preceding
 // sleep() took much longer than anticipated and workers have started timing
@@ -50,6 +50,9 @@ assert.sameValue(
   'Atomics.wake(i32a, 0, WAKECOUNT) equals the value of `WAKECOUNT` (2)'
 );
 
+// Sleep past the timeout
+$262.agent.sleep(300);
+
 // Collect and check results
 var rs = [];
 for (var i = 0; i < NUMAGENT; i++) {
diff --git a/test/built-ins/Atomics/wake/wake-zero.js b/test/built-ins/Atomics/wake/wake-zero.js
index f4c6066496..b9725e3a00 100644
--- a/test/built-ins/Atomics/wake/wake-zero.js
+++ b/test/built-ins/Atomics/wake/wake-zero.js
@@ -9,26 +9,26 @@ includes: [atomicsHelper.js]
 features: [Atomics, SharedArrayBuffer, TypedArray]
 ---*/
 
-var NUMAGENT = 3;
-var WAKEUP = 0;                 // Agents wait here
-var RUNNING = 1;                // Accounting of live agents here
-var NUMELEM = 2;
-var WAKECOUNT = 0;
+const WAKECOUNT = 0;
+const WAIT_INDEX = 0;             // Agents wait here
+const RUNNING = 1;                // Accounting of live agents here
+const NUMAGENT = 3;
+const BUFFER_SIZE = 4;
 
 for (var i = 0; i < NUMAGENT; i++) {
-$262.agent.start(`
-  $262.agent.receiveBroadcast(function(sab) {
-    const i32a = new Int32Array(sab);
-    Atomics.add(i32a, ${RUNNING}, 1);
-    // Waiters that are not woken will time out eventually.
-    $262.agent.report(Atomics.wait(i32a, ${WAKEUP}, 0, 200));
-    $262.agent.leaving();
-  });
-`);
+  $262.agent.start(`
+    $262.agent.receiveBroadcast(function(sab) {
+      const i32a = new Int32Array(sab);
+      Atomics.add(i32a, ${RUNNING}, 1);
+      // Waiters that are not woken will time out eventually.
+      $262.agent.report(Atomics.wait(i32a, ${WAIT_INDEX}, 0, 200));
+      $262.agent.leaving();
+    });
+  `);
 }
 
 const i32a = new Int32Array(
-  new SharedArrayBuffer(NUMELEM * Int32Array.BYTES_PER_ELEMENT)
+  new SharedArrayBuffer(Int32Array.BYTES_PER_ELEMENT * BUFFER_SIZE)
 );
 
 $262.agent.broadcast(i32a.buffer);
@@ -36,30 +36,18 @@ $262.agent.broadcast(i32a.buffer);
 // Wait for agents to be running.
 waitUntil(i32a, RUNNING, NUMAGENT);
 
-// Then wait some more to give the agents a fair chance to wait.  If we don't,
-// we risk sending the wakeup before agents are sleeping, and we hang.
-$262.agent.sleep(50);
-
 // There's a slight risk we'll fail to wake the desired count, if the preceding
 // sleep() took much longer than anticipated and workers have started timing
 // out.
 assert.sameValue(
-  Atomics.wake(i32a, 0, WAKECOUNT),
+  Atomics.wake(i32a, WAIT_INDEX, WAKECOUNT),
   WAKECOUNT,
-  'Atomics.wake(i32a, 0, WAKECOUNT) equals the value of `WAKECOUNT` (0)'
+  'Atomics.wake(i32a, WAIT_INDEX, WAKECOUNT) equals the value of `WAKECOUNT` (0)'
 );
 
-// Collect and check results
-var rs = [];
+// Sleep past the timeout
+$262.agent.sleep(300);
+
 for (var i = 0; i < NUMAGENT; i++) {
-  rs.push(getReport());
+  assert.sameValue(getReport(), 'timed-out', `Report #${i}: must equal "timed-out"`);
 }
-rs.sort();
-
-for (var i = 0; i < WAKECOUNT; i++) {
-  assert.sameValue(rs[i], 'ok', 'The value of rs[i] is "ok"');
-}
-for (var i = WAKECOUNT; i < NUMAGENT; i++) {
-  assert.sameValue(rs[i], 'timed-out', 'The value of rs[i] is "timed-out"');
-}
-