1 files changed, 40 insertions, 0 deletions
diff --git a/js/src/jit-test/tests/wasm/spectre-mask.js b/js/src/jit-test/tests/wasm/spectre-mask.js
new file mode 100644
index 0000000000..76e91d778e
--- /dev/null
+++ b/js/src/jit-test/tests/wasm/spectre-mask.js
@@ -0,0 +1,40 @@
+// |jit-test| skip-if: !hasDisassembler() || !(wasmCompileMode() == "baseline" || wasmCompileMode() == "ion") || !(getBuildConfiguration().x64 && !getBuildConfiguration()["arm64-simulator"] && !getBuildConfiguration()["mips64-simulator"])
+
+// What we can't test here is the direct-call-from-JIT path, as the generated
+// code is not available to wasmDis.
+
+var ins = wasmEvalText(`
+(module
+  (import "" "wasm2import" (func $g (result i32)))
+  (memory 1)
+  (type $ty (func (result i32)))
+  (table $t 1 1 funcref)
+  (func $f (result i32)
+    (i32.const 37))
+  (func (export "wasm2wasm") (result i32)
+    (call $f))
+  (func (export "wasm2import") (result i32)
+    (call $g))
+  (func (export "wasmIndirect") (result i32)
+    (call_indirect (type $ty) $t (i32.const 0)))
+  (func (export "instanceCall") (result i32)
+    (memory.size))
+)`, {'':{'wasm2import': function() {}}});
+
+switch (wasmCompileMode()) {
+case "ion":
+    assertEq(wasmDis(ins.exports.wasm2wasm, 'stable', true).match(/call.*\n.*mov %eax, %eax/).length, 1);
+    assertEq(wasmDis(ins.exports.wasm2import, 'stable', true).match(/call.*\n(?:.*movq.*\n)*.*mov %eax, %eax/).length, 1);
+    assertEq(wasmDis(ins.exports.wasmIndirect, 'stable', true).match(/call.*\n(?:.*movq.*\n)*.*mov %eax, %eax/).length, 1);
+    assertEq(wasmDis(ins.exports.instanceCall, 'stable', true).match(/call.*\n(?:.*movq.*\n)*.*mov %eax, %eax/).length, 1);
+    break;
+case "baseline":
+    assertEq(wasmDis(ins.exports.wasm2wasm, 'stable', true).match(/call.*\n.*add.*%rsp\n.*mov %eax, %eax/).length, 1);
+    assertEq(wasmDis(ins.exports.wasm2import, 'stable', true).match(/call.*\n.*add.*%rsp\n(?:.*movq.*\n)*.*mov %eax, %eax/).length, 1);
+    assertEq(wasmDis(ins.exports.wasmIndirect, 'stable', true).match(/call.*\n.*add.*%rsp\n(?:.*movq.*\n)*.*mov %eax, %eax/).length, 1);
+    assertEq(wasmDis(ins.exports.instanceCall, 'stable', true).match(/call.*\n.*add.*%rsp\n(?:.*movq.*\n)*.*mov %eax, %eax/).length, 1);
+    break;
+default:
+    throw "Unexpected compile mode";
+}
+