Serialize/Deserialize JSRegExp.

Summary: Serialize/deserialize JSRegExp.

Reviewed By: avp

Differential Revision: D16663531

fbshipit-source-id: a4b715ee288b576093ba54dbdf4b080b15fa059d

include/hermes/VM/Deserializer.h

@@ -73,6 +73,19 @@ class Deserializer {
     offset_ += size;
   }
 
+  /// Read serialize data and return as an ArrayRef<T>. Read in total \p size
+  /// elements of type T and increase the offset accordingly.
+  template <typename T>
+  ArrayRef<T> readArrayRef(size_t size) {
+    assert(offset_ + size >= offset_ && "Read overflowed");
+    assert(
+        buffer_->getBufferStart() + offset_ + size < buffer_->getBufferEnd() &&
+        "Deserialize read out of range");
+    ArrayRef<T> res((const T *)buffer_->getBufferStart() + offset_, size);
+    offset_ += size * sizeof(T);
+    return res;
+  }
+
   template <typename T>
   T readInt() {
     static_assert(std::is_integral<T>::value, "T must be integral for readInt");

include/hermes/VM/JSRegExp.h

@@ -106,6 +106,13 @@ class JSRegExp final : public JSObject {
       uint32_t searchStartOffset);
 
  private:
+#ifdef HERMESVM_SERIALIZE
+  explicit JSRegExp(Deserializer &d);
+
+  friend void RegExpSerialize(Serializer &s, const GCCell *cell);
+  friend void RegExpDeserialize(Deserializer &d, CellKind kind);
+#endif
+
   JSRegExp(Runtime *runtime, JSObject *parent, HiddenClass *clazz)
       : JSObject(runtime, &vt.base, parent, clazz) {}
 

lib/VM/JSRegExp.cpp

@@ -51,13 +51,28 @@ void RegExpBuildMeta(const GCCell *cell, Metadata::Builder &mb) {
 }
 
 #ifdef HERMESVM_SERIALIZE
+JSRegExp::JSRegExp(Deserializer &d) : JSObject(d, &vt.base) {
+  size_t size = d.readInt<size_t>();
+  bytecode_ = d.readArrayRef<uint8_t>(size);
+  d.readData(&flagBits_, sizeof(flagBits_));
+}
+
 void RegExpSerialize(Serializer &s, const GCCell *cell) {
-  LLVM_DEBUG(llvm::dbgs() << "Serialize function not implemented for RegExp\n");
+  auto *self = vmcast<const JSRegExp>(cell);
+  JSObject::serializeObjectImpl(s, cell);
+  s.writeInt<size_t>(self->bytecode_.size());
+  s.writeData(self->bytecode_.begin(), self->bytecode_.size());
+  s.writeData(&self->flagBits_, sizeof(self->flagBits_));
+
+  s.endObject(cell);
 }
 
 void RegExpDeserialize(Deserializer &d, CellKind kind) {
-  LLVM_DEBUG(
-      llvm::dbgs() << "Deserialize function not implemented for RegExp\n");
+  assert(kind == CellKind::RegExpKind && "Expected RegExp");
+  void *mem = d.getRuntime()->alloc</*fixedSize*/ true, HasFinalizer::Yes>(
+      sizeof(JSRegExp));
+  auto *cell = new (mem) JSRegExp(d);
+  d.endObject(cell);
 }
 #endif