1 files changed, 61 insertions, 0 deletions
diff --git a/js/src/jit-test/tests/wasm/ref-types/externref-global-prebarrier.js b/js/src/jit-test/tests/wasm/ref-types/externref-global-prebarrier.js
new file mode 100644
index 0000000000..139f71e758
--- /dev/null
+++ b/js/src/jit-test/tests/wasm/ref-types/externref-global-prebarrier.js
@@ -0,0 +1,61 @@
+// Do not run the test if we're jit-compiling JS, since it's the wasm frames
+// we're interested in and eager JS compilation can upset the test.
+
+opts = getJitCompilerOptions();
+if (opts['ion.enable'] || opts['baseline.enable'])
+  quit();
+
+const { startProfiling, endProfiling, assertEqPreciseStacks, isSingleStepProfilingEnabled } = WasmHelpers;
+
+let e = wasmEvalText(`(module
+    (global $g (mut externref) (ref.null extern))
+    (func (export "set") (param externref) local.get 0 global.set $g)
+)`).exports;
+
+let obj = { field: null };
+
+// GCZeal mode 4 implies that prebarriers are being verified at many
+// locations in the interpreter, during interrupt checks, etc. It can be ultra
+// slow, so disable it with gczeal(0) when it's not strictly needed.
+gczeal(4, 1);
+e.set(obj);
+e.set(null);
+gczeal(0);
+
+if (!isSingleStepProfilingEnabled) {
+    quit(0);
+}
+
+enableGeckoProfiling();
+startProfiling();
+gczeal(4, 1);
+e.set(obj);
+gczeal(0);
+assertEqPreciseStacks(
+    endProfiling(),
+    [
+        // Expected output for (simulator+via-Ion/baseline).
+        ['', '!>', '0,!>', '<,0,!>', 'GC postbarrier,0,!>',
+         '<,0,!>', '0,!>', '!>', ''],
+
+        // Expected output for other configurations.
+        ['', '!>', '0,!>', '!>', ''],
+    ]);
+
+startProfiling();
+gczeal(4, 1);
+e.set(null);
+gczeal(0);
+
+// We're losing stack info in the prebarrier code.
+assertEqPreciseStacks(
+    endProfiling(),
+    [
+        // Expected output for (simulator+via-Ion/baseline).
+        ['', '!>', '0,!>', '', '0,!>', '<,0,!>', 'GC postbarrier,0,!>',
+         '<,0,!>', '0,!>', '!>', ''],
+
+        // Expected output for other configurations.
+        ['', '!>', '0,!>', '', '0,!>', '!>', ''],
+    ]);
+