GlobalValue: Assert symbols with local linkage have default visibility

The change to ExtractGV.cpp has no functionality change except to avoid
the asserts.  Existing testcases already cover this, so I didn't add a
new one.

llvm-svn: 208264

2 files changed, 12 insertions, 5 deletions

diff --git a/llvm/include/llvm/IR/GlobalValue.h b/llvm/include/llvm/IR/GlobalValue.h
index 84343001112..51b9380ec1c 100644
--- a/llvm/include/llvm/IR/GlobalValue.h
+++ b/llvm/include/llvm/IR/GlobalValue.h
@@ -93,7 +93,11 @@ public:
   bool hasProtectedVisibility() const {
     return Visibility == ProtectedVisibility;
   }
-  void setVisibility(VisibilityTypes V) { Visibility = V; }
+  void setVisibility(VisibilityTypes V) {
+    assert((!hasLocalLinkage() || V == DefaultVisibility) &&
+           "local linkage requires default visibility");
+    Visibility = V;
+  }
 
   DLLStorageClassTypes getDLLStorageClass() const {
     return DLLStorageClassTypes(DllStorageClass);
@@ -195,7 +199,11 @@ public:
   bool hasExternalWeakLinkage() const { return isExternalWeakLinkage(Linkage); }
   bool hasCommonLinkage() const { return isCommonLinkage(Linkage); }
 
-  void setLinkage(LinkageTypes LT) { Linkage = LT; }
+  void setLinkage(LinkageTypes LT) {
+    assert((!isLocalLinkage(LT) || hasDefaultVisibility()) &&
+           "local linkage requires default visibility");
+    Linkage = LT;
+  }
   LinkageTypes getLinkage() const { return Linkage; }
 
   bool isDiscardableIfUnused() const {
diff --git a/llvm/lib/Transforms/IPO/ExtractGV.cpp b/llvm/lib/Transforms/IPO/ExtractGV.cpp
index 408713a2c24..40ec9fa8c1d 100644
--- a/llvm/lib/Transforms/IPO/ExtractGV.cpp
+++ b/llvm/lib/Transforms/IPO/ExtractGV.cpp
@@ -27,11 +27,10 @@ using namespace llvm;
 /// the split module remain valid.
 static void makeVisible(GlobalValue &GV, bool Delete) {
   bool Local = GV.hasLocalLinkage();
-  if (Local)
-    GV.setVisibility(GlobalValue::HiddenVisibility);
-
   if (Local || Delete) {
     GV.setLinkage(GlobalValue::ExternalLinkage);
+    if (Local)
+      GV.setVisibility(GlobalValue::HiddenVisibility);
     return;
   }