1 files changed, 20 insertions, 2 deletions
diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp
index fb600e0b577..75e03a50f39 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.cpp
+++ b/llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -2780,6 +2780,24 @@ X86TargetLowering::LowerCall(TargetLowering::CallLoweringInfo &CLI,
   if (MF.getTarget().Options.DisableTailCalls)
     isTailCall = false;
 
+  if (Subtarget->isPICStyleGOT() &&
+      !MF.getTarget().Options.GuaranteedTailCallOpt) {
+    // If we are using a GOT, disable tail calls to external symbols with
+    // default visibility. Tail calling such a symbol requires using a GOT
+    // relocation, which forces early binding of the symbol. This breaks code
+    // that require lazy function symbol resolution. Using musttail or
+    // GuaranteedTailCallOpt will override this.
+    GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee);
+    if (!G || (!G->getGlobal()->hasLocalLinkage() &&
+               G->getGlobal()->hasDefaultVisibility())) {
+      isTailCall = false;
+      if (G) {
+        llvm::errs() << "disabling tail call for default visibility symbol\n";
+        G->getGlobal()->dump();
+      }
+    }
+  }
+
   bool IsMustTail = CLI.CS && CLI.CS->isMustTailCall();
   if (IsMustTail) {
     // Force this to be a tail call.  The verifier rules are enough to ensure
@@ -2964,8 +2982,8 @@ X86TargetLowering::LowerCall(TargetLowering::CallLoweringInfo &CLI,
 
       // Note: The actual moving to ECX is done further down.
       GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee);
-      if (G && !G->getGlobal()->hasHiddenVisibility() &&
-          !G->getGlobal()->hasProtectedVisibility())
+      if (G && !G->getGlobal()->hasLocalLinkage() &&
+          G->getGlobal()->hasDefaultVisibility())
         Callee = LowerGlobalAddress(Callee, DAG);
       else if (isa<ExternalSymbolSDNode>(Callee))
         Callee = LowerExternalSymbol(Callee, DAG);