Fix lost store side effects with escape analysis.

This preserves side effects from stores in HCapturedObject markers so
that simulates following these markers are not merged away.

R=titzer@chromium.org
TEST=mjsunit/compiler/escape-analysis --deopt-every-n-times [3,6,9]

Review URL: https://codereview.chromium.org/23554003

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16394 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

diff --git a/src/hydrogen-escape-analysis.cc b/src/hydrogen-escape-analysis.cc
index 311091b..b508644 100644 (file)
--- a/src/hydrogen-escape-analysis.cc
+++ b/src/hydrogen-escape-analysis.cc
@@ -172,11 +172,14 @@ void HEscapeAnalysisPhase::AnalyzeDataFlow(HInstruction* allocate) {
           int index = store->access().offset() / kPointerSize;
           if (store->object() != allocate) continue;
           ASSERT(store->access().IsInobject());
-          state = NewStateCopy(store, state);
+          state = NewStateCopy(store->previous(), state);
           state->SetOperandAt(index, store->value());
           if (store->has_transition()) {
             state->SetOperandAt(0, store->transition());
           }
+          if (store->HasObservableSideEffects()) {
+            state->ReuseSideEffectsFromStore(store);
+          }
           store->DeleteAndReplaceWith(NULL);
           if (FLAG_trace_escape_analysis) {
             PrintF("Replacing store #%d%s\n", instr->id(),

diff --git a/src/hydrogen-instructions.h b/src/hydrogen-instructions.h
index 8f79edf..773ba3b 100644 (file)
--- a/src/hydrogen-instructions.h
+++ b/src/hydrogen-instructions.h
@@ -3230,6 +3230,12 @@ class HCapturedObject V8_FINAL : public HDematerializedObject {
   int length() const { return values_.length(); }
   int capture_id() const { return capture_id_; }
 
+  void ReuseSideEffectsFromStore(HInstruction* store) {
+    ASSERT(store->HasObservableSideEffects());
+    ASSERT(store->IsStoreNamedField());
+    gvn_flags_.Add(store->gvn_flags());
+  }
+
   // Replay effects of this instruction on the given environment.
   void ReplayEnvironment(HEnvironment* env);