diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
@@ -143,8 +143,6 @@
   auto *GVContext = GV->getScope();
   const DIType *GTy = GV->getType();
 
-  // Construct the context before querying for the existence of the DIE in
-  // case such construction creates the DIE.
   auto *CB = GVContext ? dyn_cast<DICommonBlock>(GVContext) : nullptr;
   DIE *ContextDIE = CB ? getOrCreateCommonBlock(CB, GlobalExprs)
     : getOrCreateContextDIE(GVContext);
@@ -351,12 +349,10 @@
 
 DIE *DwarfCompileUnit::getOrCreateCommonBlock(
     const DICommonBlock *CB, ArrayRef<GlobalExpr> GlobalExprs) {
-  // Construct the context before querying for the existence of the DIE in case
-  // such construction creates the DIE.
-  DIE *ContextDIE = getOrCreateContextDIE(CB->getScope());
-
+  // Check for pre-existence.
   if (DIE *NDie = getDIE(CB))
     return NDie;
+  DIE *ContextDIE = getOrCreateContextDIE(CB->getScope());
   DIE &NDie = createAndAddDIE(dwarf::DW_TAG_common_block, *ContextDIE, CB);
   StringRef Name = CB->getName().empty() ? "_BLNK_" : CB->getName();
   addString(NDie, dwarf::DW_AT_name, Name);