DIBuilder: retain a type when created with a unique identifier.

createClassType, createStructType, createUnionType, createEnumerationType,
and createForwardDecl will retain a type when created with a unique identifier,
to make sure they are treated as used even when all uses are replaced with
the identifiers.

Use TrackingVH<MDNode> instead of MDNode in AllRetainTypes, since the created
node can later be updated.

The change will be tested when clients of DIBuilder start to pass in non-empty
unique identifier.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@189621 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 4 insertions, 1 deletions

diff --git a/include/llvm/DIBuilder.h b/include/llvm/DIBuilder.h
index a4c43473b1..d4dfadc5c7 100644
--- a/include/llvm/DIBuilder.h
+++ b/include/llvm/DIBuilder.h
@@ -18,6 +18,7 @@
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/Support/DataTypes.h"
+#include "llvm/Support/ValueHandle.h"
 
 namespace llvm {
   class BasicBlock;
@@ -65,7 +66,9 @@ namespace llvm {
     Function *ValueFn;       // llvm.dbg.value
 
     SmallVector<Value *, 4> AllEnumTypes;
-    SmallVector<Value *, 4> AllRetainTypes;
+    /// Use TrackingVH to collect RetainTypes, since they can be updated
+    /// later on.
+    SmallVector<TrackingVH<MDNode>, 4> AllRetainTypes;
     SmallVector<Value *, 4> AllSubprograms;
     SmallVector<Value *, 4> AllGVs;
     SmallVector<Value *, 4> AllImportedModules;