VM: Cache instructions entry point in RawFunction/RawCode.

runtime/vm/raw_object.h

Index: runtime/vm/raw_object.h
diff --git a/runtime/vm/raw_object.h b/runtime/vm/raw_object.h
index 23140edb5a14d5ee3c73951ccd5930082832eeb9..fe8425911540386ea12e78ffe4233d2b07b323bc 100644
--- a/runtime/vm/raw_object.h
+++ b/runtime/vm/raw_object.h
@@ -771,6 +771,7 @@ class RawFunction : public RawObject {
   RawObject** to() {
     return reinterpret_cast<RawObject**>(&ptr()->unoptimized_code_);
   }
+  uword entry_point_;
 
   int32_t token_pos_;
   int32_t end_token_pos_;
@@ -1003,6 +1004,7 @@ class RawCode : public RawObject {
   RawObject** to() {
     return reinterpret_cast<RawObject**>(&ptr()->comments_);
   }
+  uword entry_point_;
 
   // Compilation timestamp.
   int64_t compile_timestamp_;