[NVPTX] Emit .weak linkage for link_once, weak, available_externally, and common linkage

llvm-svn: 211941

llvm/lib/Target/NVPTX/NVPTXAsmPrinter.cpp

@@ -1367,6 +1367,10 @@ void NVPTXAsmPrinter::printModuleLevelGV(const GlobalVariable *GVar,
       O << ".visible ";
     else
       O << ".extern ";
+  } else if (GVar->hasLinkOnceLinkage() || GVar->hasWeakLinkage() ||
+             GVar->hasAvailableExternallyLinkage() ||
+             GVar->hasCommonLinkage()) {
+    O << ".weak ";
   }
 
   if (llvm::isTexture(*GVar)) {

llvm/test/CodeGen/NVPTX/weak-global.ll

@@ -0,0 +1,9 @@
+; RUN: llc < %s -march=nvptx -mcpu=sm_20 | FileCheck %s
+
+; CHECK: .weak .global .align 4 .u32 g
+@g = common addrspace(1) global i32 zeroinitializer
+
+define i32 @func0() {
+  %val = load i32 addrspace(1)* @g
+  ret i32 %val
+}