VM: Precompiled rodata snapshot.

runtime/vm/isolate.cc

Index: runtime/vm/isolate.cc
diff --git a/runtime/vm/isolate.cc b/runtime/vm/isolate.cc
index 5c764df99fef660f2e0a21bf014d6906716efc79..99ec4b2a3f2d51f6d1cbfa2c57145d2739e5cd17 100644
--- a/runtime/vm/isolate.cc
+++ b/runtime/vm/isolate.cc
@@ -974,10 +974,28 @@ void Isolate::SetupInstructionsSnapshotPage(
   }
 #endif
   heap_->SetupInstructionsSnapshotPage(snapshot.instructions_start(),
-                                       snapshot.instructions_size());
+                                       snapshot.instructions_size(),
+                                       /* is_executable = */ true);
 }
 
 
+void Isolate::SetupDataSnapshotPage(const uint8_t* data_snapshot_buffer) {
+  DataSnapshot snapshot(data_snapshot_buffer);
+#if defined(DEBUG)
+  if (FLAG_trace_isolates) {
+    OS::Print("Precompiled rodata are at [0x%" Px ", 0x%" Px ")\n",
+              reinterpret_cast<uword>(snapshot.data_start()),
+              reinterpret_cast<uword>(snapshot.data_start()) +
+              snapshot.data_size());
+  }
+#endif
+  heap_->SetupInstructionsSnapshotPage(snapshot.data_start(),
+                                       snapshot.data_size(),
+                                       /* is_executable = */ false);
+}
+
+
+
 void Isolate::set_debugger_name(const char* name) {
   free(debugger_name_);
   debugger_name_ = strdup(name);