[wasm] Embedder can control what buffers wasm compilation works on.

src/runtime/runtime-test.cc

Index: src/runtime/runtime-test.cc
diff --git a/src/runtime/runtime-test.cc b/src/runtime/runtime-test.cc
index 3185ee07d17f109d9a49094c0d5fcb6be0dbc63c..3bfc2dab9c84db2a661abe14bf3522b6552f0b6b 100644
--- a/src/runtime/runtime-test.cc
+++ b/src/runtime/runtime-test.cc
@@ -19,6 +19,45 @@
 #include "src/wasm/wasm-module.h"
 #include "src/wasm/wasm-objects.h"
 
+namespace {
+struct WasmCompileControls {
+  uint32_t MaxWasmBufferSize = std::numeric_limits<uint32_t>::max();
+  bool AllowAnySizeForAsync = true;
+};
+
+// We need per-isolate controls, because we sometimes run tests in multiple
+// isolates
+// concurrently.
+// To avoid upsetting the static initializer count, we lazy initialize this.
+v8::base::LazyInstance<std::map<v8::Isolate*, WasmCompileControls>>::type
+    g_PerIsolateWasmControls = LAZY_INSTANCE_INITIALIZER;
+
+bool IsWasmCompileAllowed(v8::Isolate* isolate, v8::Local<v8::Value> value,
+                          bool is_async) {
+  DCHECK_GT(g_PerIsolateWasmControls.Get().count(isolate), 0);
+  const WasmCompileControls& ctrls = g_PerIsolateWasmControls.Get().at(isolate);
+  return (is_async && ctrls.AllowAnySizeForAsync) ||
+         (v8::Local<v8::ArrayBuffer>::Cast(value)->ByteLength() <=
+          ctrls.MaxWasmBufferSize);
+}
+
+// Use the compile controls for instantiation, too
+bool IsWasmInstantiateAllowed(v8::Isolate* isolate,
+                              v8::Local<v8::Value> module_or_bytes,
+                              v8::MaybeLocal<v8::Value> ffi, bool is_async) {
+  DCHECK_GT(g_PerIsolateWasmControls.Get().count(isolate), 0);
+  const WasmCompileControls& ctrls = g_PerIsolateWasmControls.Get().at(isolate);
+  if (is_async && ctrls.AllowAnySizeForAsync) return true;
+  if (!module_or_bytes->IsWebAssemblyCompiledModule()) {
+    return IsWasmCompileAllowed(isolate, module_or_bytes, is_async);
+  }
+  v8::Local<v8::WasmCompiledModule> module =
+      v8::Local<v8::WasmCompiledModule>::Cast(module_or_bytes);
+  return static_cast<uint32_t>(module->GetWasmWireBytes()->Length()) <=
+         ctrls.MaxWasmBufferSize;
+}
+}  // namespace
+
 namespace v8 {
 namespace internal {
 
@@ -429,6 +468,26 @@ RUNTIME_FUNCTION(Runtime_CheckWasmWrapperElision) {
   return isolate->heap()->ToBoolean(count == 1);
 }
 
+RUNTIME_FUNCTION(Runtime_SetWasmCompileControls) {
+  HandleScope scope(isolate);
+  v8::Isolate* v8_isolate = reinterpret_cast<v8::Isolate*>(isolate);
+  CHECK(args.length() == 2);
+  CONVERT_ARG_HANDLE_CHECKED(Smi, block_size, 0);
+  CONVERT_BOOLEAN_ARG_CHECKED(allow_async, 1);
+  WasmCompileControls& ctrl = (*g_PerIsolateWasmControls.Pointer())[v8_isolate];
+  ctrl.AllowAnySizeForAsync = allow_async;
+  ctrl.MaxWasmBufferSize = static_cast<uint32_t>(block_size->value());
+  isolate->set_allow_wasm_compile_callback(IsWasmCompileAllowed);
+  return isolate->heap()->undefined_value();
+}
+
+RUNTIME_FUNCTION(Runtime_SetWasmInstantiateControls) {
+  HandleScope scope(isolate);
+  CHECK(args.length() == 0);
+  isolate->set_allow_wasm_instantiate_callback(IsWasmInstantiateAllowed);
+  return isolate->heap()->undefined_value();
+}
+
 RUNTIME_FUNCTION(Runtime_NotifyContextDisposed) {
   HandleScope scope(isolate);
   DCHECK_EQ(0, args.length());