[DIBuilder] Add a more fine-grained finalization method

Summary:
Clang wants to clone a function before it is done building the entire
compilation unit. As of now, there is no good way to do that, because
CloneFunction doesn't like dealing with temporary metadata. However,
as long as clang doesn't want to add any variables to this SP, it
should be fine to just prematurely finalize it. Add an API to allow this.

This is done in preparation of a clang commit to fix the assertion that
necessitated the revert of D33655.

Reviewers: aprantl, dblaikie

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D33704

llvm-svn: 304467

1 files changed, 17 insertions, 16 deletions

diff --git a/llvm/lib/IR/DIBuilder.cpp b/llvm/lib/IR/DIBuilder.cpp
index 7e6f9a7804b..7754ac03b43 100644
--- a/llvm/lib/IR/DIBuilder.cpp
+++ b/llvm/lib/IR/DIBuilder.cpp
@@ -39,6 +39,21 @@ void DIBuilder::trackIfUnresolved(MDNode *N) {
   UnresolvedNodes.emplace_back(N);
 }
 
+void DIBuilder::finalizeSubprogram(DISubprogram *SP) {
+  MDTuple *Temp = SP->getVariables().get();
+  if (!Temp || !Temp->isTemporary())
+    return;
+
+  SmallVector<Metadata *, 4> Variables;
+
+  auto PV = PreservedVariables.find(SP);
+  if (PV != PreservedVariables.end())
+    Variables.append(PV->second.begin(), PV->second.end());
+
+  DINodeArray AV = getOrCreateArray(Variables);
+  TempMDTuple(Temp)->replaceAllUsesWith(AV.get());
+}
+
 void DIBuilder::finalize() {
   if (!CUNode) {
     assert(!AllowUnresolvedNodes &&
@@ -62,25 +77,11 @@ void DIBuilder::finalize() {
     CUNode->replaceRetainedTypes(MDTuple::get(VMContext, RetainValues));
 
   DISubprogramArray SPs = MDTuple::get(VMContext, AllSubprograms);
-  auto resolveVariables = [&](DISubprogram *SP) {
-    MDTuple *Temp = SP->getVariables().get();
-    if (!Temp)
-      return;
-
-    SmallVector<Metadata *, 4> Variables;
-
-    auto PV = PreservedVariables.find(SP);
-    if (PV != PreservedVariables.end())
-      Variables.append(PV->second.begin(), PV->second.end());
-
-    DINodeArray AV = getOrCreateArray(Variables);
-    TempMDTuple(Temp)->replaceAllUsesWith(AV.get());
-  };
   for (auto *SP : SPs)
-    resolveVariables(SP);
+    finalizeSubprogram(SP);
   for (auto *N : RetainValues)
     if (auto *SP = dyn_cast<DISubprogram>(N))
-      resolveVariables(SP);
+      finalizeSubprogram(SP);
 
   if (!AllGVs.empty())
     CUNode->replaceGlobalVariables(MDTuple::get(VMContext, AllGVs));