Avoid zeroing out spilled register lists for OOL

This fixes a tricky bug which is detailed in #5977. See the aforementioned issue for a full explanation.
eclipse · Apr 30, 2021 · 7d3ca8f · 7d3ca8f
1 parent 6ed62c2
commit 7d3ca8f
Showing 1 changed file with 7 additions and 4 deletions.
diff --git a/compiler/codegen/OMRCodeGenerator.cpp b/compiler/codegen/OMRCodeGenerator.cpp
@@ -844,11 +844,14 @@ OMR::CodeGenerator::doRegisterAssignment(TR_RegisterKinds kindsToAssign)
    TR::Instruction *prevInstr = NULL;
    TR::Instruction *currInstr = self()->getAppendInstruction();
 
-   auto *firstTimeLiveOOLRegisterList = new (self()->trHeapMemory()) TR::list<TR::Register*>(getTypedAllocator<TR::Register*>(self()->comp()->allocator()));
-   self()->setFirstTimeLiveOOLRegisterList(firstTimeLiveOOLRegisterList);
+   if (!self()->isOutOfLineColdPath())
+      {
+      auto *firstTimeLiveOOLRegisterList = new (self()->trHeapMemory()) TR::list<TR::Register*>(getTypedAllocator<TR::Register*>(self()->comp()->allocator()));
+      self()->setFirstTimeLiveOOLRegisterList(firstTimeLiveOOLRegisterList);
 
-   auto *spilledRegisterList = new (self()->trHeapMemory()) TR::list<TR::Register*>(getTypedAllocator<TR::CFGEdge*>(self()->comp()->allocator()));
-   self()->setSpilledRegisterList(spilledRegisterList);
+      auto *spilledRegisterList = new (self()->trHeapMemory()) TR::list<TR::Register*>(getTypedAllocator<TR::CFGEdge*>(self()->comp()->allocator()));
+      self()->setSpilledRegisterList(spilledRegisterList);
+      }
 
    if (self()->getDebug())
       {