[wasm] Fix serialization after instantiation

test/mjsunit/wasm/compiled-module-serialization.js

 // Copyright 2015 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: --expose-wasm --allow-natives-syntax --expose-gc
 
 load("test/mjsunit/wasm/wasm-constants.js");
 load("test/mjsunit/wasm/wasm-module-builder.js");
 
 (function SerializeAndDeserializeModule() {
@@ skipping 19 matching lines @@
   // writer(mem[i]);
   // return mem[i] + some_value();
   builder.addFunction("_wrap_writer", signature)
     .addBody([
       kExprGetLocal, 0,
       kExprCallFunction, 1]);
   builder.appendToTable([2, 3]);
 
   var wire_bytes = builder.toBuffer();
   var module = new WebAssembly.Module(wire_bytes);
-  var buff = %SerializeWasmModule(module);
-  module = null;
-  gc();
-  module = %DeserializeWasmModule(buff, wire_bytes);
-
   var mem_1 = new WebAssembly.Memory({initial: 1});
   var view_1 = new Int32Array(mem_1.buffer);
-
   view_1[0] = 42;
-
   var outval_1;
   var i1 = new WebAssembly.Instance(module, {"":
                                              {some_value: () => 1,
                                               writer: (x) => outval_1 = x ,
                                               memory: mem_1}
                                             });
 
   assertEquals(43, i1.exports.main(0));
 
   assertEquals(42, outval_1);
+  var buff = %SerializeWasmModule(module);
+  module = null;
+  gc();
+  module = %DeserializeWasmModule(buff, wire_bytes);
+
+  var mem_2 = new WebAssembly.Memory({initial: 2});
+  var view_2 = new Int32Array(mem_2.buffer);
+
+  view_2[0] = 50;
+
+  var outval_2;
+  var i2 = new WebAssembly.Instance(module, {"":
+                                             {some_value: () => 1,
+                                              writer: (x) => outval_2 = x ,
+                                              memory: mem_2}
+                                            });
+
+  assertEquals(51, i2.exports.main(0));
+
+  assertEquals(50, outval_2);
+  // The instances don't share memory through deserialization.
+  assertEquals(43, i1.exports.main(0));
 })();
 
 (function DeserializeInvalidObject() {
   var invalid_buffer = new ArrayBuffer(10);
 
   module = %DeserializeWasmModule(invalid_buffer, invalid_buffer);
   assertEquals(module, undefined);
 })();
 
 (function RelationBetweenModuleAndClone() {
@@ skipping 26 matching lines @@
   var serialized = %SerializeWasmModule(compiled_module);
   var clone = %DeserializeWasmModule(serialized, wire_bytes);
 
   assertNotNull(clone);
   assertFalse(clone == undefined);
   assertFalse(clone == compiled_module);
   assertEquals(clone.constructor, compiled_module.constructor);
   var instance3 = new WebAssembly.Instance(clone);
   assertFalse(instance3 == undefined);
 })();
+
+
+(function SerializeAfterInstantiationWithMemory() {
+  let builder = new WasmModuleBuilder();
+  builder.addImportedMemory("", "memory", 1);
+  builder.addFunction("main", kSig_i_v)
+    .addBody([kExprI32Const, 42])
+    .exportFunc();
+
+  var wire_bytes = builder.toBuffer()
+  var compiled_module = new WebAssembly.Module(wire_bytes);
+  var mem_1 = new WebAssembly.Memory({initial: 1});
+  var ffi =  {"":{memory:mem_1}};
+  var instance1 = new WebAssembly.Instance(compiled_module, ffi);
+  var serialized = %SerializeWasmModule(compiled_module);
+  var clone = %DeserializeWasmModule(serialized, wire_bytes);
+
+  assertNotNull(clone);
+  assertFalse(clone == undefined);
+  assertFalse(clone == compiled_module);
+  assertEquals(clone.constructor, compiled_module.constructor);
+  var instance2 = new WebAssembly.Instance(clone, ffi);
+  assertFalse(instance2 == undefined);
+})();
+
+(function GlobalsArePrivateBetweenClones() {
+  var builder = new WasmModuleBuilder();
+  builder.addGlobal(kWasmI32, true);
+  builder.addFunction("read", kSig_i_v)
+    .addBody([
+      kExprGetGlobal, 0])
+    .exportFunc();
+
+  builder.addFunction("write", kSig_v_i)
+    .addBody([
+      kExprGetLocal, 0,
+      kExprSetGlobal, 0])
+    .exportFunc();
+
+  var wire_bytes = builder.toBuffer();
+  var module = new WebAssembly.Module(wire_bytes);
+  var i1 = new WebAssembly.Instance(module);
+  // serialize and replace module
+  var buff = %SerializeWasmModule(module);
+  module = %DeserializeWasmModule(buff, wire_bytes);

[bradnelson, 2017/03/29 20:49:07]

Any reason to drop the link to the old one here? I.e. now a collect might drop
the old one.

[Mircea Trofin, 2017/03/29 20:56:30]

Done.

+  var i2 = new WebAssembly.Instance(module);
+  i1.exports.write(1);
+  i2.exports.write(2);
+  assertEquals(1, i1.exports.read());
+  assertEquals(2, i2.exports.read());
+})();
+

[bradnelson, 2017/03/29 20:49:07]

You're inconsistent with lines skipped between tests here and above, maybe match
the file?

[Mircea Trofin, 2017/03/29 20:56:30]

Done.

+
+(function SharedTableTest() {
+  let kTableSize = 3;
+  var sig_index1;
+
+  function MakeTableExportingModule(constant) {

[bradnelson, 2017/03/29 20:49:07]

Indent weird here.

[Mircea Trofin, 2017/03/29 20:56:30]

Done.

+  // A module that defines a table and exports it.
+    var builder = new WasmModuleBuilder();
+    builder.addType(kSig_i_i);
+    builder.addType(kSig_i_ii);
+    sig_index1 = builder.addType(kSig_i_v);
+    var f1 = builder.addFunction("f1", sig_index1)
+        .addBody([kExprI32Const, constant]);
+
+    builder.addFunction("main", kSig_i_ii)
+      .addBody([
+        kExprGetLocal, 0,   // --
+        kExprCallIndirect, sig_index1, kTableZero])  // --
+      .exportAs("main");
+
+    builder.setFunctionTableLength(kTableSize);
+    builder.addFunctionTableInit(0, false, [f1.index]);
+    builder.addExportOfKind("table", kExternalTable, 0);
+
+    return new WebAssembly.Module(builder.toBuffer());
+  }
+  var m1 = MakeTableExportingModule(11);
+
+  // Module {m2} imports the table and adds {f2}.
+  var builder = new WasmModuleBuilder();
+  builder.addType(kSig_i_ii);
+  var sig_index2 = builder.addType(kSig_i_v);
+  var f2 = builder.addFunction("f2", sig_index2)
+    .addBody([kExprI32Const, 22]);
+
+  builder.addFunction("main", kSig_i_ii)
+    .addBody([
+      kExprGetLocal, 0,   // --
+      kExprCallIndirect, sig_index2, kTableZero])  // --
+    .exportAs("main");
+
+  builder.addImportedTable("z", "table", kTableSize, kTableSize);
+  builder.addFunctionTableInit(1, false, [f2.index], true);
+  var m2_bytes = builder.toBuffer();
+  var m2 = new WebAssembly.Module(m2_bytes);
+
+  assertFalse(sig_index1 == sig_index2);
+
+  var i1 = new WebAssembly.Instance(m1);
+  var i2 = new WebAssembly.Instance(m2, {z: {table: i1.exports.table}});
+
+  var serialized_m2 = %SerializeWasmModule(m2);
+  var m2_clone = %DeserializeWasmModule(serialized_m2, m2_bytes);

[bradnelson, 2017/03/29 20:49:07]

Worth a variant where you force a GC to ensure links to the old one are gone?

[Mircea Trofin, 2017/03/29 20:56:30]

We test that we execute instance-specific functionality correctly. If we didn't
let go of references, we'd see leaked instance functionality, and also, we
wouldn't collect anything (because the reference would stay alive).

+
+  var m3 = MakeTableExportingModule(33);
+  var i3 = new WebAssembly.Instance(m3);
+  var i2_prime = new WebAssembly.Instance(m2_clone, {z: {table: i3.exports.table}});

[Mircea Trofin, 2017/03/29 20:56:30]

Done.

+
+  assertEquals(11, i1.exports.main(0));
+  assertEquals(11, i2.exports.main(0));
+
+  assertEquals(22, i1.exports.main(1));
+  assertEquals(22, i2.exports.main(1));
+
+  assertEquals(33, i3.exports.main(0));
+  assertEquals(33, i2_prime.exports.main(0));
+
+  assertThrows(() => i1.exports.main(2));
+  assertThrows(() => i2.exports.main(2));
+  assertThrows(() => i1.exports.main(3));
+  assertThrows(() => i2.exports.main(3));
+
+})();