Fix transaction records for `fill-array-data`.

We need to record old array elements, not the new ones, so
call `RecordArrayElementsInTransaction()` earlier. Move the
implementation where it's actually needed, check for NPE
(due to the reordering) and avoid unnecessary read barriers.

Test: m test-art-host-gtest
Test: testrunner.py --host --optimizing --interp-ac
Change-Id: I6282afed941b1a32468aceb970c3e72283b445ba

1 files changed, 2 insertions, 3 deletions

diff --git a/runtime/interpreter/interpreter_switch_impl-inl.h b/runtime/interpreter/interpreter_switch_impl-inl.h
index ec152a5d07..ce0117f724 100644
--- a/runtime/interpreter/interpreter_switch_impl-inl.h
+++ b/runtime/interpreter/interpreter_switch_impl-inl.h
@@ -721,12 +721,11 @@ class InstructionHandler {
     const Instruction::ArrayDataPayload* payload =
         reinterpret_cast<const Instruction::ArrayDataPayload*>(payload_addr);
     ObjPtr<mirror::Object> obj = GetVRegReference(A());
+    // If we have an active transaction, record old values before we overwrite them.
+    TransactionChecker::RecordArrayElementsInTransaction(obj, payload->element_count);
     if (!FillArrayData(obj, payload)) {
       return false;  // Pending exception.
     }
-    if (transaction_active) {
-      RecordArrayElementsInTransaction(obj->AsArray(), payload->element_count);
-    }
     return true;
   }