Add Atomics.notify instead of Atomics.wake according to revised spec.

- Keep .wake as an alias until we're certain it can be removed.
- Enable SAB memory

5 files changed, 30 insertions, 34 deletions

diff --git a/js/src/builtin/AtomicsObject.cpp b/js/src/builtin/AtomicsObject.cpp
index 2551f3b7d..3de3f5f4c 100644
--- a/js/src/builtin/AtomicsObject.cpp
+++ b/js/src/builtin/AtomicsObject.cpp
@@ -834,7 +834,7 @@ js::atomics_wait(JSContext* cx, unsigned argc, Value* vp)
 }
 
 bool
-js::atomics_wake(JSContext* cx, unsigned argc, Value* vp)
+js::atomics_notify(JSContext* cx, unsigned argc, Value* vp)
 {
     CallArgs args = CallArgsFromVp(argc, vp);
     HandleValue objv = args.get(0);
@@ -874,7 +874,7 @@ js::atomics_wake(JSContext* cx, unsigned argc, Value* vp)
             iter = iter->lower_pri;
             if (c->offset != offset || !c->rt->fx.isWaiting())
                 continue;
-            c->rt->fx.wake(FutexRuntime::WakeExplicit);
+            c->rt->fx.notify(FutexRuntime::NotifyExplicit);
             ++woken;
             --count;
         } while (count > 0 && iter != waiters);
@@ -950,7 +950,7 @@ js::FutexRuntime::isWaiting()
     // When a worker is awoken for an interrupt it goes into state
     // WaitingNotifiedForInterrupt for a short time before it actually
     // wakes up and goes into WaitingInterrupted.  In those states the
-    // worker is still waiting, and if an explicit wake arrives the
+    // worker is still waiting, and if an explicit notify arrives the
     // worker transitions to Woken.  See further comments in
     // FutexRuntime::wait().
     return state_ == Waiting || state_ == WaitingInterrupted || state_ == WaitingNotifiedForInterrupt;
@@ -1029,14 +1029,14 @@ js::FutexRuntime::wait(JSContext* cx, js::UniqueLock<js::Mutex>& locked,
             //   should be woken when the interrupt handler returns.
             //   To that end, we flag the thread as interrupted around
             //   the interrupt and check state_ when the interrupt
-            //   handler returns.  A wake() call that reaches the
+            //   handler returns.  A notify() call that reaches the
             //   runtime during the interrupt sets state_ to Woken.
             //
             // - It is in principle possible for wait() to be
             //   reentered on the same thread/runtime and waiting on the
             //   same location and to yet again be interrupted and enter
             //   the interrupt handler.  In this case, it is important
-            //   that when another agent wakes waiters, all waiters using
+            //   that when another agent notifies waiters, all waiters using
             //   the same runtime on the same location are woken in LIFO
             //   order; FIFO may be the required order, but FIFO would
             //   fail to wake up the innermost call.  Interrupts are
@@ -1073,25 +1073,25 @@ finished:
 }
 
 void
-js::FutexRuntime::wake(WakeReason reason)
+js::FutexRuntime::notify(NotifyReason reason)
 {
     MOZ_ASSERT(isWaiting());
 
-    if ((state_ == WaitingInterrupted || state_ == WaitingNotifiedForInterrupt) && reason == WakeExplicit) {
+    if ((state_ == WaitingInterrupted || state_ == WaitingNotifiedForInterrupt) && reason == NotifyExplicit) {
         state_ = Woken;
         return;
     }
     switch (reason) {
-      case WakeExplicit:
+      case NotifyExplicit:
         state_ = Woken;
         break;
-      case WakeForJSInterrupt:
+      case NotifyForJSInterrupt:
         if (state_ == WaitingNotifiedForInterrupt)
             return;
         state_ = WaitingNotifiedForInterrupt;
         break;
       default:
-        MOZ_CRASH("bad WakeReason in FutexRuntime::wake()");
+        MOZ_CRASH("bad NotifyReason in FutexRuntime::notify()");
     }
     cond_->notify_all();
 }
@@ -1108,7 +1108,8 @@ const JSFunctionSpec AtomicsMethods[] = {
     JS_INLINABLE_FN("xor",                atomics_xor,                3,0, AtomicsXor),
     JS_INLINABLE_FN("isLockFree",         atomics_isLockFree,         1,0, AtomicsIsLockFree),
     JS_FN("wait",                         atomics_wait,               4,0),
-    JS_FN("wake",                         atomics_wake,               3,0),
+    JS_FN("notify",                       atomics_notify,             3,0),
+    JS_FN("wake",                         atomics_notify,             3,0), //Legacy name
     JS_FS_END
 };
 
diff --git a/js/src/builtin/AtomicsObject.h b/js/src/builtin/AtomicsObject.h
index adb6fb986..6511dc8bf 100644
--- a/js/src/builtin/AtomicsObject.h
+++ b/js/src/builtin/AtomicsObject.h
@@ -36,7 +36,7 @@ MOZ_MUST_USE bool atomics_or(JSContext* cx, unsigned argc, Value* vp);
 MOZ_MUST_USE bool atomics_xor(JSContext* cx, unsigned argc, Value* vp);
 MOZ_MUST_USE bool atomics_isLockFree(JSContext* cx, unsigned argc, Value* vp);
 MOZ_MUST_USE bool atomics_wait(JSContext* cx, unsigned argc, Value* vp);
-MOZ_MUST_USE bool atomics_wake(JSContext* cx, unsigned argc, Value* vp);
+MOZ_MUST_USE bool atomics_notify(JSContext* cx, unsigned argc, Value* vp);
 
 /* asm.js callouts */
 namespace wasm { class Instance; }
@@ -63,10 +63,10 @@ public:
     MOZ_MUST_USE bool initInstance();
     void destroyInstance();
 
-    // Parameters to wake().
-    enum WakeReason {
-        WakeExplicit,           // Being asked to wake up by another thread
-        WakeForJSInterrupt      // Interrupt requested
+    // Parameters to notify().
+    enum NotifyReason {
+        NotifyExplicit,           // Being asked to wake up by another thread
+        NotifyForJSInterrupt      // Interrupt requested
     };
 
     // Result code from wait().
@@ -83,29 +83,27 @@ public:
     // times allowed; specify mozilla::Nothing() for an indefinite
     // wait.
     //
-    // wait() will not wake up spuriously.  It will return true and
-    // set *result to a return code appropriate for
-    // Atomics.wait() on success, and return false on error.
+    // wait() will not wake up spuriously.
     MOZ_MUST_USE bool wait(JSContext* cx, js::UniqueLock<js::Mutex>& locked,
                            mozilla::Maybe<mozilla::TimeDuration>& timeout, WaitResult* result);
 
-    // Wake the thread represented by this Runtime.
+    // Notify the thread represented by this Runtime.
     //
     // The futex lock must be held around this call.  (The sleeping
-    // thread will not wake up until the caller of Atomics.wake()
+    // thread will not wake up until the caller of Atomics.notify()
     // releases the lock.)
     //
     // If the thread is not waiting then this method does nothing.
     //
     // If the thread is waiting in a call to wait() and the
-    // reason is WakeExplicit then the wait() call will return
+    // reason is NotifyExplicit then the wait() call will return
     // with Woken.
     //
     // If the thread is waiting in a call to wait() and the
-    // reason is WakeForJSInterrupt then the wait() will return
+    // reason is NotifyForJSInterrupt then the wait() will return
     // with WaitingNotifiedForInterrupt; in the latter case the caller
     // of wait() must handle the interrupt.
-    void wake(WakeReason reason);
+    void notify(NotifyReason reason);
 
     bool isWaiting();
 
@@ -128,7 +126,7 @@ public:
                                      //   interrupt handler
         WaitingInterrupted,          // We are waiting, but have been interrupted
                                      //   and are running the interrupt handler
-        Woken                        // Woken by a script call to Atomics.wake
+        Woken                        // Woken by a script call to Atomics.notify
     };
 
     // Condition variable that this runtime will wait on.
diff --git a/js/src/tests/shell/futex.js b/js/src/tests/shell/futex.js
index b0951f12e..8ba61d71c 100644
--- a/js/src/tests/shell/futex.js
+++ b/js/src/tests/shell/futex.js
@@ -67,6 +67,8 @@ if (helperThreadCount() === 0) {
   quit();
 }
 
+var mem = new Int32Array(new SharedArrayBuffer(1024));
+
 ////////////////////////////////////////////////////////////
 
 // wait() returns "not-equal" if the value is not the expected one.
@@ -102,7 +104,7 @@ dprint("Sleeping for 2 seconds");
 sleep(2);
 dprint("Waking the main thread now");
 setSharedArrayBuffer(null);
-assertEq(Atomics.wake(mem, 0, 1), 1); // Can fail spuriously but very unlikely
+assertEq(Atomics.notify(mem, 0, 1), 1); // Can fail spuriously but very unlikely
 `);
 
 var then = Date.now();
@@ -113,14 +115,14 @@ assertEq(getSharedArrayBuffer(), null); // The worker's clearing of the mbx is v
 
 ////////////////////////////////////////////////////////////
 
-// Test the default argument to atomics.wake()
+// Test the default argument to atomics.notify()
 
 setSharedArrayBuffer(mem.buffer);
 
 evalInWorker(`
 var mem = new Int32Array(getSharedArrayBuffer());
 sleep(2);				// Probably long enough to avoid a spurious error next
-assertEq(Atomics.wake(mem, 0), 1);	// Last argument to wake should default to +Infinity
+assertEq(Atomics.notify(mem, 0), 1);	// Last argument to wake should default to +Infinity
 `);
 
 var then = Date.now();
diff --git a/js/src/vm/Runtime.cpp b/js/src/vm/Runtime.cpp
index 8eb997c71..5fc8e0e17 100644
--- a/js/src/vm/Runtime.cpp
+++ b/js/src/vm/Runtime.cpp
@@ -589,7 +589,7 @@ JSRuntime::requestInterrupt(InterruptMode mode)
         // Atomics.wait().
         fx.lock();
         if (fx.isWaiting())
-            fx.wake(FutexRuntime::WakeForJSInterrupt);
+            fx.notify(FutexRuntime::NotifyForJSInterrupt);
         fx.unlock();
         InterruptRunningJitCode(this);
     }
diff --git a/modules/libpref/init/all.js b/modules/libpref/init/all.js
index d5005cbdd..f761c70b9 100644
--- a/modules/libpref/init/all.js
+++ b/modules/libpref/init/all.js
@@ -1319,12 +1319,7 @@ pref("javascript.options.mem.gc_max_empty_chunk_count", 30);
 
 pref("javascript.options.showInConsole", false);
 
-#ifdef RELEASE_OR_BETA
-// Disabled in Beta and Release for now, see bug 1225406
-pref("javascript.options.shared_memory", false);
-#else
 pref("javascript.options.shared_memory", true);
-#endif
 
 pref("javascript.options.throw_on_debuggee_would_run", false);
 pref("javascript.options.dump_stack_on_debuggee_would_run", false);