[NVPTX] Emit .weak when linkage is not external, internal, or private

llvm-svn: 211926

2 files changed, 19 insertions, 0 deletions

diff --git a/llvm/lib/Target/NVPTX/NVPTXAsmPrinter.cpp b/llvm/lib/Target/NVPTX/NVPTXAsmPrinter.cpp
index c2ba12df859..34de7bbd8a6 100644
--- a/llvm/lib/Target/NVPTX/NVPTXAsmPrinter.cpp
+++ b/llvm/lib/Target/NVPTX/NVPTXAsmPrinter.cpp
@@ -1305,6 +1305,10 @@ bool NVPTXAsmPrinter::doFinalization(Module &M) {
 // external global variable with init     -> .visible
 // external without init                  -> .extern
 // appending                              -> not allowed, assert.
+// for any linkage other than
+// internal, private, linker_private,
+// linker_private_weak, linker_private_weak_def_auto,
+// we emit                                -> .weak.
 
 void NVPTXAsmPrinter::emitLinkageDirective(const GlobalValue *V,
                                            raw_ostream &O) {
@@ -1330,6 +1334,9 @@ void NVPTXAsmPrinter::emitLinkageDirective(const GlobalValue *V,
         msg.append(V->getName().str());
       msg.append("has unsupported appending linkage type");
       llvm_unreachable(msg.c_str());
+    } else if (!V->hasInternalLinkage() &&
+               !V->hasPrivateLinkage()) {
+      O << ".weak ";
     }
   }
 }
diff --git a/llvm/test/CodeGen/NVPTX/weak-linkage.ll b/llvm/test/CodeGen/NVPTX/weak-linkage.ll
new file mode 100644
index 00000000000..7a133578364
--- /dev/null
+++ b/llvm/test/CodeGen/NVPTX/weak-linkage.ll
@@ -0,0 +1,12 @@
+; RUN: llc < %s -march=nvptx -mcpu=sm_20 | FileCheck %s
+
+
+; CHECK: .weak .func foo
+define weak void @foo() {
+  ret void
+}
+
+; CHECK: .visible .func bar
+define void @bar() {
+  ret void
+}