Temporarily revert r65994. It was causing rdar://6646455.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66083 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 6 insertions, 20 deletions

diff --git a/lib/Transforms/IPO/GlobalOpt.cpp b/lib/Transforms/IPO/GlobalOpt.cpp
index 28cd902..0a35fa9 100644
--- a/lib/Transforms/IPO/GlobalOpt.cpp
+++ b/lib/Transforms/IPO/GlobalOpt.cpp
@@ -137,23 +137,15 @@ struct VISIBILITY_HIDDEN GlobalStatus {
 }
 
 /// ConstantIsDead - Return true if the specified constant is (transitively)
-/// dead.  The constant may be used by other constants (e.g. constant arrays,
-/// constant exprs, constant global variables) as long as they are dead, 
-/// but it cannot be used by anything else. If DeadGVs is not null then
-/// record dead constant GV users.
-static bool ConstantIsDead(Constant *C, 
-                           SmallPtrSet<GlobalVariable *, 4> *DeadGVs = false) {
-  if (GlobalVariable *GV = dyn_cast<GlobalVariable>(C))
-    if (GV->hasLocalLinkage() && GV->use_empty()) {
-      if (DeadGVs)
-        DeadGVs->insert(GV);
-      return true;
-    }
+/// dead.  The constant may be used by other constants (e.g. constant arrays and
+/// constant exprs) as long as they are dead, but it cannot be used by anything
+/// else.
+static bool ConstantIsDead(Constant *C) {
   if (isa<GlobalValue>(C)) return false;
 
   for (Value::use_iterator UI = C->use_begin(), E = C->use_end(); UI != E; ++UI)
     if (Constant *CU = dyn_cast<Constant>(*UI)) {
-      if (!ConstantIsDead(CU, DeadGVs)) return false;
+      if (!ConstantIsDead(CU)) return false;
     } else
       return false;
   return true;
@@ -346,13 +338,7 @@ static bool CleanupConstantGlobalUsers(Value *V, Constant *Init) {
     } else if (Constant *C = dyn_cast<Constant>(U)) {
       // If we have a chain of dead constantexprs or other things dangling from
       // us, and if they are all dead, nuke them without remorse.
-      SmallPtrSet<GlobalVariable *, 4> DeadGVs;
-      if (ConstantIsDead(C, &DeadGVs)) {
-        for (SmallPtrSet<GlobalVariable *, 4>::iterator TI = DeadGVs.begin(),
-               TE = DeadGVs.end(); TI != TE; ) {
-          GlobalVariable *TGV = *TI; ++TI;
-          TGV->eraseFromParent();
-        }
+      if (ConstantIsDead(C)) {
         C->destroyConstant();
         // This could have invalidated UI, start over from scratch.
         CleanupConstantGlobalUsers(V, Init);