[wasm-gc] JS interop: Test import/export of wasm objects

Bug: v8:7748
Change-Id: I1d4d951b67546e0403854b96b04b681ce101deaf
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3902053
Auto-Submit: Matthias Liedtke <mliedtke@chromium.org>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Matthias Liedtke <mliedtke@chromium.org>
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/main@{#83321}

test/mjsunit/mjsunit.status

@@ -35,6 +35,7 @@
   'regress/modules-skip*': [SKIP],
   'wasm/exceptions-utils': [SKIP],
   'wasm/gc-js-interop-helpers': [SKIP],
+  'wasm/gc-js-interop-export': [SKIP],
   'wasm/wasm-module-builder': [SKIP],
   'compiler/fast-api-helpers': [SKIP],
   'typedarray-helpers': [SKIP],

test/mjsunit/wasm/gc-js-interop-export.mjs

+// Copyright 2022 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+d8.file.execute('test/mjsunit/wasm/gc-js-interop-helpers.js');
+export let {struct, array} = CreateWasmObjects();

test/mjsunit/wasm/gc-js-interop-helpers.js

@@ -8,6 +8,7 @@ d8.file.execute('test/mjsunit/wasm/wasm-module-builder.js');
 
 function CreateWasmObjects() {
   let builder = new WasmModuleBuilder();
+  builder.setSingletonRecGroups();
   let struct_type = builder.addStruct([makeField(kWasmI32, true)]);
   let array_type = builder.addArray(kWasmI32, true);
   builder.addFunction('MakeStruct', makeSig([], [kWasmExternRef]))

test/mjsunit/wasm/gc-js-interop-import.mjs

+// Copyright 2022 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Flags: --experimental-wasm-gc --wasm-gc-js-interop --allow-natives-syntax
+
+import {struct, array} from 'gc-js-interop-export.mjs';
+
+// Read struct and array with new wasm module.
+let builder = new WasmModuleBuilder();
+builder.setSingletonRecGroups();
+let struct_type = builder.addStruct([makeField(kWasmI32, true)]);
+let array_type = builder.addArray(kWasmI32, true);
+builder.addFunction('readStruct', makeSig([kWasmExternRef], [kWasmI32]))
+    .exportFunc()
+    .addBody([
+      kExprLocalGet, 0,                           // --
+      kGCPrefix, kExprExternInternalize,          // --
+      kGCPrefix, kExprRefAsData,                  // --
+      kGCPrefix, kExprRefCast, struct_type,       // --
+      kGCPrefix, kExprStructGet, struct_type, 0,  // --
+    ]);
+builder.addFunction('readArrayLength', makeSig([kWasmExternRef], [kWasmI32]))
+    .exportFunc()
+    .addBody([
+      kExprLocalGet, 0,                           // --
+      kGCPrefix, kExprExternInternalize,          // --
+      kGCPrefix, kExprRefAsArray,                 // --
+      kGCPrefix, kExprArrayLen,
+    ]);
+
+let instance = builder.instantiate();
+let wasm = instance.exports;
+assertEquals(42, wasm.readStruct(struct));
+assertEquals(2, wasm.readArrayLength(array));
+assertTraps(kTrapIllegalCast, () => wasm.readStruct(array));
+assertTraps(kTrapIllegalCast, () => wasm.readArrayLength(struct));

test/mjsunit/wasm/gc-js-interop.js

@@ -275,12 +275,6 @@ for (const wasm_obj of [struct, array]) {
     assertThrows(() => gen().next(), TypeError);
   });
 
-  // FIXME(mliedtke): Should we repeat the same testing for async generator
-  // functions as for the synchronous ones?
-
   // Ensure no statement re-assigned wasm_obj by accident.
   assertTrue(wasm_obj == struct || wasm_obj == array);
 }
-
-// TODO(mliedtke): What about `export {struct, array}`?
-// d8 doesn't seem to accept exports (as the file isn't a module?)