Option to output precompiled instructions as a blob for use with mmap instead of assembly for use i…

runtime/vm/datastream.h

Index: runtime/vm/datastream.h
diff --git a/runtime/vm/datastream.h b/runtime/vm/datastream.h
index f47e822bd8ed4657e9af80f79bb73f862f0ff1a2..58452a07f64afc36b617ed0a8cfbfe36d0caa8f3 100644
--- a/runtime/vm/datastream.h
+++ b/runtime/vm/datastream.h
@@ -387,6 +387,16 @@ class WriteStream : public ValueObject {
     current_ += len;
   }
 
+  void WriteWord(uword value) {
+    const intptr_t len = sizeof(uword);
+    if ((end_ - current_) < len) {
+      Resize(len);
+    }
+    ASSERT((end_ - current_) >= len);
+    *reinterpret_cast<uword*>(current_) = value;
+    current_ += len;
+  }
+
   void Print(const char* format, ...) {
     va_list args;
     va_start(args, format);