Implement the isSafeToDiscardIfUnused predicate and use it in globalopt and

globaldce. Globaldce was already removing linkonce globals, but globalopt was
not.

llvm-svn: 158476

2 files changed, 4 insertions, 4 deletions

diff --git a/llvm/lib/Transforms/IPO/GlobalDCE.cpp b/llvm/lib/Transforms/IPO/GlobalDCE.cpp
index 2b427aa6a4e..18c1c7b0005 100644
--- a/llvm/lib/Transforms/IPO/GlobalDCE.cpp
+++ b/llvm/lib/Transforms/IPO/GlobalDCE.cpp
@@ -65,7 +65,7 @@ bool GlobalDCE::runOnModule(Module &M) {
   for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) {
     Changed |= RemoveUnusedGlobalValue(*I);
     // Functions with external linkage are needed if they have a body
-    if (!I->hasLocalLinkage() && !I->hasLinkOnceLinkage() &&
+    if (!I->isDiscardableIfUnused() &&
         !I->isDeclaration() && !I->hasAvailableExternallyLinkage())
       GlobalIsNeeded(I);
   }
@@ -75,7 +75,7 @@ bool GlobalDCE::runOnModule(Module &M) {
     Changed |= RemoveUnusedGlobalValue(*I);
     // Externally visible & appending globals are needed, if they have an
     // initializer.
-    if (!I->hasLocalLinkage() && !I->hasLinkOnceLinkage() &&
+    if (!I->isDiscardableIfUnused() &&
         !I->isDeclaration() && !I->hasAvailableExternallyLinkage())
       GlobalIsNeeded(I);
   }
@@ -84,7 +84,7 @@ bool GlobalDCE::runOnModule(Module &M) {
        I != E; ++I) {
     Changed |= RemoveUnusedGlobalValue(*I);
     // Externally visible aliases are needed.
-    if (!I->hasLocalLinkage() && !I->hasLinkOnceLinkage())
+    if (!I->isDiscardableIfUnused())
       GlobalIsNeeded(I);
   }
 
diff --git a/llvm/lib/Transforms/IPO/GlobalOpt.cpp b/llvm/lib/Transforms/IPO/GlobalOpt.cpp
index d316d526785..9e3b8c28269 100644
--- a/llvm/lib/Transforms/IPO/GlobalOpt.cpp
+++ b/llvm/lib/Transforms/IPO/GlobalOpt.cpp
@@ -1716,7 +1716,7 @@ static bool TryToShrinkGlobalToBoolean(GlobalVariable *GV, Constant *OtherVal) {
 /// possible.  If we make a change, return true.
 bool GlobalOpt::ProcessGlobal(GlobalVariable *GV,
                               Module::global_iterator &GVI) {
-  if (!GV->hasLocalLinkage())
+  if (!GV->isDiscardableIfUnused())
     return false;
 
   // Do more involved optimizations if the global is internal.