1 files changed, 10 insertions, 1 deletions
diff --git a/runtime/jdwp/jdwp_event.cc b/runtime/jdwp/jdwp_event.cc
index 6908047..adc1074 100644
--- a/runtime/jdwp/jdwp_event.cc
+++ b/runtime/jdwp/jdwp_event.cc
@@ -233,7 +233,16 @@ void JdwpState::UnregisterEvent(JdwpEvent* pEvent) {
       Dbg::UnconfigureStep(pMod->step.threadId);
     }
   }
-  if (NeedsFullDeoptimization(pEvent->eventKind)) {
+  if (pEvent->eventKind == EK_SINGLE_STEP) {
+    // Special case for single-steps where we want to avoid the slow pattern deoptimize/undeoptimize
+    // loop between each single-step. In a IDE, this would happens each time the user click on the
+    // "single-step" button. Here we delay the full undeoptimization to the next resume
+    // (VM.Resume or ThreadReference.Resume) or the end of the debugging session (VM.Dispose or
+    // runtime shutdown).
+    // Therefore, in a singles-stepping sequence, only the first single-step will trigger a full
+    // deoptimization and only the last single-step will trigger a full undeoptimization.
+    Dbg::DelayFullUndeoptimization();
+  } else if (NeedsFullDeoptimization(pEvent->eventKind)) {
     CHECK_EQ(req.kind, DeoptimizationRequest::kNothing);
     CHECK(req.method == nullptr);
     req.kind = DeoptimizationRequest::kFullUndeoptimization;