DebugInfo: Only move types out of type units if they're named or type united

Follow up to r359122, after a bug was reported in it - the original
change too aggressively tried to move related types out of type units,
which included unnamed types (like array types) which can't reasonably
be declared-but-not-defined.

A step beyond that is that some types in type units can be anonymous, if
they are types with a name for linkage purposes (eg: "typedef struct { }
x;"). So ensure those don't get turned into plain declarations (without
signatures) because, lacking names, they can't be resolved to the
definition.

[Also include a fix for llvm-dwarfdump/libDebugInfoDWARF to pretty print
types in type units]

llvm-svn: 360458

1 files changed, 2 insertions, 1 deletions

diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
index 3aa404ed4e9..d9e680846b3 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
@@ -639,7 +639,8 @@ DIE *DwarfUnit::createTypeDIE(const DIScope *Context, DIE &ContextDIE,
   else if (auto *STy = dyn_cast<DISubroutineType>(Ty))
     constructTypeDIE(TyDIE, STy);
   else if (auto *CTy = dyn_cast<DICompositeType>(Ty)) {
-    if (DD->generateTypeUnits() && !Ty->isForwardDecl()) {
+    if (DD->generateTypeUnits() && !Ty->isForwardDecl() &&
+        (Ty->getRawName() || CTy->getRawIdentifier())) {
       // Skip updating the accelerator tables since this is not the full type.
       if (MDString *TypeId = CTy->getRawIdentifier())
         DD->addDwarfTypeUnitType(getCU(), TypeId->getString(), TyDIE, CTy);