[OPENMP][NVPTX]Fix PR40893: Size doesn't match for

'_openmp_teams_reductions_buffer_$_.

nvlink does not handle weak linkage correctly, same symbols with the
different sizes are reported as erroneous though the largest size must
be chosen instead. Patch fixes this problem by using Internal linkage
instead of the Common.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@356072 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/CGOpenMPRuntimeNVPTX.cpp

@@ -5050,9 +5050,12 @@ void CGOpenMPRuntimeNVPTX::clear() {
       QualType Arr2Ty = C.getConstantArrayType(Arr1Ty, Size2, ArrayType::Normal,
                                                /*IndexTypeQuals=*/0);
       llvm::Type *LLVMArr2Ty = CGM.getTypes().ConvertTypeForMem(Arr2Ty);
+      // FIXME: nvlink does not handle weak linkage correctly (object with the
+      // different size are reported as erroneous).
+      // Restore CommonLinkage as soon as nvlink is fixed.
       auto *GV = new llvm::GlobalVariable(
           CGM.getModule(), LLVMArr2Ty,
-          /*isConstant=*/false, llvm::GlobalValue::CommonLinkage,
+          /*isConstant=*/false, llvm::GlobalValue::InternalLinkage,
           llvm::Constant::getNullValue(LLVMArr2Ty),
           "_openmp_static_glob_rd_$_");
       auto *Replacement = llvm::ConstantExpr::getPointerBitCastOrAddrSpaceCast(
@@ -5082,9 +5085,12 @@ void CGOpenMPRuntimeNVPTX::clear() {
     QualType StaticTy = C.getRecordType(StaticRD);
     llvm::Type *LLVMReductionsBufferTy =
         CGM.getTypes().ConvertTypeForMem(StaticTy);
+    // FIXME: nvlink does not handle weak linkage correctly (object with the
+    // different size are reported as erroneous).
+    // Restore CommonLinkage as soon as nvlink is fixed.
     auto *GV = new llvm::GlobalVariable(
         CGM.getModule(), LLVMReductionsBufferTy,
-        /*isConstant=*/false, llvm::GlobalValue::CommonLinkage,
+        /*isConstant=*/false, llvm::GlobalValue::InternalLinkage,
         llvm::Constant::getNullValue(LLVMReductionsBufferTy),
         "_openmp_teams_reductions_buffer_$_");
     KernelTeamsReductionPtr->setInitializer(

test/OpenMP/nvptx_teams_reduction_codegen.cpp

@@ -28,7 +28,7 @@
 // CHECK-DAG: {{@__omp_offloading_.+l47}}_exec_mode = weak constant i8 1
 // CHECK-DAG: {{@__omp_offloading_.+l54}}_exec_mode = weak constant i8 0
 
-// CHECK-DAG: [[TEAMS_RED_BUFFER:@.+]] = common global [[TEAMS_REDUCE_UNION_TY]] zeroinitializer
+// CHECK-DAG: [[TEAMS_RED_BUFFER:@.+]] = internal global [[TEAMS_REDUCE_UNION_TY]] zeroinitializer
 
 template<typename tx>
 tx ftemplate(int n) {