Index: src/lithium-allocator.cc |
diff --git a/src/lithium-allocator.cc b/src/lithium-allocator.cc |
index 9f5f1b97d8d60b0c5a084963224e4d98303f3401..d745b0c8d4f9a34fcfd878e6808b838494a16de2 100644 |
--- a/src/lithium-allocator.cc |
+++ b/src/lithium-allocator.cc |
@@ -1098,6 +1098,21 @@ void LAllocator::ResolveControlFlow(LiveRange* range, |
} else { |
ASSERT(pred->end()->SecondSuccessor() == NULL); |
gap = GetLastGap(pred); |
+ |
+ // We are going to insert mov from one live-range to another before the |
+ // branch instruction. Some branch instructions (e.g. loops' back edges) |
+ // can potentially cause a GC so they have a pointer map. |
+ // By insterting a move we essentially create a copy of a |
+ // value which is invisible to PopulatePointerMaps(), because we store |
+ // it into a location different from the operand of a live range |
+ // covering a branch instruction. |
+ // Thus we need to manually record a pointer. |
+ if (HasTaggedValue(range->id())) { |
+ LInstruction* branch = InstructionAt(pred->last_instruction_index()); |
+ if (branch->HasPointerMap()) { |
+ branch->pointer_map()->RecordPointer(cur_op); |
+ } |
+ } |
} |
gap->GetOrCreateParallelMove(LGap::START)->AddMove(pred_op, cur_op); |
} |