1 files changed, 44 insertions, 0 deletions
diff --git a/js/src/jit-test/tests/atomics/store-does-not-truncate-returnval.js b/js/src/jit-test/tests/atomics/store-does-not-truncate-returnval.js
new file mode 100644
index 0000000000..f689511ba4
--- /dev/null
+++ b/js/src/jit-test/tests/atomics/store-does-not-truncate-returnval.js
@@ -0,0 +1,44 @@
+function test(SharedOrUnsharedArrayBuffer) {
+var ia = new Int32Array(new SharedOrUnsharedArrayBuffer(4));
+
+// Atomics.store() returns the input value converted to integer as if
+// by ToInteger.
+//
+// JIT and interpreter have different paths here, so loop a little to
+// trigger the JIT properly.
+
+function f() {
+    assertEq(Atomics.store(ia, 0, 3.5), 3);
+    assertEq(ia[0], 3);
+
+    assertEq(Atomics.store(ia, 0, -0), +0);
+    assertEq(ia[0], 0);
+
+    assertEq(Atomics.store(ia, 0, '4.6'), 4);
+    assertEq(ia[0], 4);
+
+    assertEq(Atomics.store(ia, 0, '-4.6'), -4);
+    assertEq(ia[0], -4);
+
+    assertEq(Atomics.store(ia, 0, undefined), 0);
+    assertEq(ia[0], 0);
+
+    assertEq(Atomics.store(ia, 0, Infinity), Infinity);
+    assertEq(ia[0], 0);
+
+    assertEq(Atomics.store(ia, 0, -Infinity), -Infinity);
+    assertEq(ia[0], 0);
+
+    assertEq(Atomics.store(ia, 0, Math.pow(2, 32)+5), Math.pow(2, 32)+5);
+    assertEq(ia[0], 5);
+
+    assertEq(Atomics.store(ia, 0, { valueOf: () => 3.7 }), 3);
+    assertEq(ia[0], 3);
+}
+
+for ( var i=0 ; i < 10 ; i++ )
+    f();
+}
+
+test(SharedArrayBuffer);
+test(ArrayBuffer);