Enable scalar replacement of AllocaInst whose one of the user is dbg info.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64207 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 22 insertions, 0 deletions

diff --git a/lib/Transforms/Utils/Local.cpp b/lib/Transforms/Utils/Local.cpp
index c22485342e..38809e5e1d 100644
--- a/lib/Transforms/Utils/Local.cpp
+++ b/lib/Transforms/Utils/Local.cpp
@@ -248,3 +248,25 @@ void llvm::MergeBasicBlockIntoOnlyPred(BasicBlock *DestBB) {
   // Nuke BB.
   PredBB->eraseFromParent();
 }
+
+/// OnlyUsedByDbgIntrinsics - Return true if the instruction I is only used
+/// by DbgIntrinsics. If DbgInUses is specified then the vector is filled 
+/// with the DbgInfoIntrinsic that use the instruction I.
+bool llvm::OnlyUsedByDbgInfoIntrinsics(Instruction *I, 
+                               SmallVectorImpl<DbgInfoIntrinsic *> *DbgInUses) {
+  if (DbgInUses)
+    DbgInUses->clear();
+
+  for (Value::use_iterator UI = I->use_begin(), UE = I->use_end(); UI != UE; 
+       ++UI) {
+    if (DbgInfoIntrinsic *DI = dyn_cast<DbgInfoIntrinsic>(*UI)) {
+      if (DbgInUses)
+        DbgInUses->push_back(DI);
+    } else {
+      if (DbgInUses)
+        DbgInUses->clear();
+      return false;
+    }
+  }
+  return true;
+}