[libomptarget][nvptx] Undef, weak shared variables

[libomptarget][nvptx] Undef, weak shared variables

Shared variables on nvptx, and LDS on amdgcn, are uninitialized at
the start of kernel execution. Therefore create the variables with
undef instead of zeros, motivated in part by the amdgcn back end
rejecting LDS+initializer.

Common is zero initialized, which seems incompatible with shared. Thus
change them to weak, following the direction of
https://reviews.llvm.org/rG7b3eabdcd215

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D90248

diff --git a/clang/lib/CodeGen/CGOpenMPRuntimeGPU.cpp b/clang/lib/CodeGen/CGOpenMPRuntimeGPU.cpp
index bcabc53..08903a1 100644 (file)
--- a/clang/lib/CodeGen/CGOpenMPRuntimeGPU.cpp
+++ b/clang/lib/CodeGen/CGOpenMPRuntimeGPU.cpp
@@ -1102,7 +1102,7 @@ void CGOpenMPRuntimeGPU::emitNonSPMDKernel(const OMPExecutableDirective &D,
     KernelStaticGlobalized = new llvm::GlobalVariable(
         CGM.getModule(), CGM.VoidPtrTy, /*isConstant=*/false,
         llvm::GlobalValue::InternalLinkage,
-        llvm::ConstantPointerNull::get(CGM.VoidPtrTy),
+        llvm::UndefValue::get(CGM.VoidPtrTy),
         "_openmp_kernel_static_glob_rd$ptr", /*InsertBefore=*/nullptr,
         llvm::GlobalValue::NotThreadLocal,
         CGM.getContext().getTargetAddressSpace(LangAS::cuda_shared));
@@ -1234,7 +1234,7 @@ void CGOpenMPRuntimeGPU::emitSPMDKernel(const OMPExecutableDirective &D,
     KernelStaticGlobalized = new llvm::GlobalVariable(
         CGM.getModule(), CGM.VoidPtrTy, /*isConstant=*/false,
         llvm::GlobalValue::InternalLinkage,
-        llvm::ConstantPointerNull::get(CGM.VoidPtrTy),
+        llvm::UndefValue::get(CGM.VoidPtrTy),
         "_openmp_kernel_static_glob_rd$ptr", /*InsertBefore=*/nullptr,
         llvm::GlobalValue::NotThreadLocal,
         CGM.getContext().getTargetAddressSpace(LangAS::cuda_shared));
@@ -2855,8 +2855,8 @@ static llvm::Value *emitInterWarpCopyFunction(CodeGenModule &CGM,
     auto *Ty = llvm::ArrayType::get(CGM.Int32Ty, WarpSize);
     unsigned SharedAddressSpace = C.getTargetAddressSpace(LangAS::cuda_shared);
     TransferMedium = new llvm::GlobalVariable(
-        M, Ty, /*isConstant=*/false, llvm::GlobalVariable::CommonLinkage,
-        llvm::Constant::getNullValue(Ty), TransferMediumName,
+        M, Ty, /*isConstant=*/false, llvm::GlobalVariable::WeakAnyLinkage,
+        llvm::UndefValue::get(Ty), TransferMediumName,
         /*InsertBefore=*/nullptr, llvm::GlobalVariable::NotThreadLocal,
         SharedAddressSpace);
     CGM.addCompilerUsedGlobal(TransferMedium);
@@ -4791,8 +4791,8 @@ void CGOpenMPRuntimeGPU::clear() {
       llvm::Type *LLVMStaticTy = CGM.getTypes().ConvertTypeForMem(StaticTy);
       auto *GV = new llvm::GlobalVariable(
           CGM.getModule(), LLVMStaticTy,
-          /*isConstant=*/false, llvm::GlobalValue::CommonLinkage,
-          llvm::Constant::getNullValue(LLVMStaticTy),
+          /*isConstant=*/false, llvm::GlobalValue::WeakAnyLinkage,
+          llvm::UndefValue::get(LLVMStaticTy),
           "_openmp_shared_static_glob_rd_$_", /*InsertBefore=*/nullptr,
           llvm::GlobalValue::NotThreadLocal,
           C.getTargetAddressSpace(LangAS::cuda_shared));

diff --git a/clang/test/OpenMP/nvptx_data_sharing.cpp b/clang/test/OpenMP/nvptx_data_sharing.cpp
index 1372246..b6117d7 100644 (file)
--- a/clang/test/OpenMP/nvptx_data_sharing.cpp
+++ b/clang/test/OpenMP/nvptx_data_sharing.cpp
@@ -28,8 +28,8 @@ void test_ds(){
   }
 }
 // SEQ: [[MEM_TY:%.+]] = type { [128 x i8] }
-// SEQ-DAG: [[SHARED_GLOBAL_RD:@.+]] = common addrspace(3) global [[MEM_TY]] zeroinitializer
-// SEQ-DAG: [[KERNEL_PTR:@.+]] = internal addrspace(3) global i8* null
+// SEQ-DAG: [[SHARED_GLOBAL_RD:@.+]] = weak addrspace(3) global [[MEM_TY]] undef
+// SEQ-DAG: [[KERNEL_PTR:@.+]] = internal addrspace(3) global i8* undef
 // SEQ-DAG: [[KERNEL_SIZE:@.+]] = internal unnamed_addr constant i64 8
 // SEQ-DAG: [[KERNEL_SHARED:@.+]] = internal unnamed_addr constant i16 1
 

diff --git a/clang/test/OpenMP/nvptx_distribute_parallel_generic_mode_codegen.cpp b/clang/test/OpenMP/nvptx_distribute_parallel_generic_mode_codegen.cpp
index 4b194a3..fef5f6f 100644 (file)
--- a/clang/test/OpenMP/nvptx_distribute_parallel_generic_mode_codegen.cpp
+++ b/clang/test/OpenMP/nvptx_distribute_parallel_generic_mode_codegen.cpp
@@ -35,8 +35,8 @@ int main(int argc, char **argv) {
 }
 
 // SEQ: [[MEM_TY:%.+]] = type { [128 x i8] }
-// SEQ-DAG: [[SHARED_GLOBAL_RD:@.+]] = common addrspace(3) global [[MEM_TY]] zeroinitializer
-// SEQ-DAG: [[KERNEL_PTR:@.+]] = internal addrspace(3) global i8* null
+// SEQ-DAG: [[SHARED_GLOBAL_RD:@.+]] = weak addrspace(3) global [[MEM_TY]] undef
+// SEQ-DAG: [[KERNEL_PTR:@.+]] = internal addrspace(3) global i8* undef
 // SEQ-DAG: [[KERNEL_SIZE:@.+]] = internal unnamed_addr constant i{{64|32}} 40
 // SEQ-DAG: [[KERNEL_SHARED:@.+]] = internal unnamed_addr constant i16 1
 // CHECK-DAG: @__omp_offloading_{{.*}}_main_[[LINE:l.+]]_exec_mode = weak constant i8 0

diff --git a/clang/test/OpenMP/nvptx_parallel_codegen.cpp b/clang/test/OpenMP/nvptx_parallel_codegen.cpp
index bd9c988..593f7fa 100644 (file)
--- a/clang/test/OpenMP/nvptx_parallel_codegen.cpp
+++ b/clang/test/OpenMP/nvptx_parallel_codegen.cpp
@@ -76,8 +76,8 @@ int bar(int n){
 }
 
 // SEQ: [[MEM_TY:%.+]] = type { [128 x i8] }
-// SEQ-DAG: [[SHARED_GLOBAL_RD:@.+]] = common addrspace(3) global [[MEM_TY]] zeroinitializer
-// SEQ-DAG: [[KERNEL_PTR:@.+]] = internal addrspace(3) global i8* null
+// SEQ-DAG: [[SHARED_GLOBAL_RD:@.+]] = weak addrspace(3) global [[MEM_TY]] undef
+// SEQ-DAG: [[KERNEL_PTR:@.+]] = internal addrspace(3) global i8* undef
 // SEQ-DAG: [[KERNEL_SIZE:@.+]] = internal unnamed_addr constant i{{64|32}} 4
 // SEQ-DAG: [[KERNEL_SHARED:@.+]] = internal unnamed_addr constant i16 1
 

diff --git a/clang/test/OpenMP/nvptx_parallel_for_codegen.cpp b/clang/test/OpenMP/nvptx_parallel_for_codegen.cpp
index 4ef167d..839e859 100644 (file)
--- a/clang/test/OpenMP/nvptx_parallel_for_codegen.cpp
+++ b/clang/test/OpenMP/nvptx_parallel_for_codegen.cpp
@@ -32,8 +32,8 @@ int bar(int n){
 }
 
 // SEQ: [[MEM_TY:%.+]] = type { [128 x i8] }
-// SEQ-DAG: [[SHARED_GLOBAL_RD:@.+]] = common addrspace(3) global [[MEM_TY]] zeroinitializer
-// SEQ-DAG: [[KERNEL_PTR:@.+]] = internal addrspace(3) global i8* null
+// SEQ-DAG: [[SHARED_GLOBAL_RD:@.+]] = weak addrspace(3) global [[MEM_TY]] undef
+// SEQ-DAG: [[KERNEL_PTR:@.+]] = internal addrspace(3) global i8* undef
 // SEQ-DAG: [[KERNEL_SIZE:@.+]] = internal unnamed_addr constant i{{64|32}} 4
 // SEQ-DAG: [[KERNEL_SHARED:@.+]] = internal unnamed_addr constant i16 1
 

diff --git a/clang/test/OpenMP/nvptx_target_parallel_reduction_codegen.cpp b/clang/test/OpenMP/nvptx_target_parallel_reduction_codegen.cpp
index 459330d..a69a9f9 100644 (file)
--- a/clang/test/OpenMP/nvptx_target_parallel_reduction_codegen.cpp
+++ b/clang/test/OpenMP/nvptx_target_parallel_reduction_codegen.cpp
@@ -9,7 +9,7 @@
 #define HEADER
 
 // Check for the data transfer medium in shared memory to transfer the reduction list to the first warp.
-// CHECK-DAG: [[TRANSFER_STORAGE:@.+]] = common addrspace([[SHARED_ADDRSPACE:[0-9]+]]) global [32 x i32]
+// CHECK-DAG: [[TRANSFER_STORAGE:@.+]] = weak addrspace([[SHARED_ADDRSPACE:[0-9]+]]) global [32 x i32]
 
 // Check that the execution mode of all 3 target regions is set to Spmd Mode.
 // CHECK-DAG: {{@__omp_offloading_.+l27}}_exec_mode = weak constant i8 0

diff --git a/clang/test/OpenMP/nvptx_target_teams_distribute_parallel_for_codegen.cpp b/clang/test/OpenMP/nvptx_target_teams_distribute_parallel_for_codegen.cpp
index d40aad3..480b34d 100644 (file)
--- a/clang/test/OpenMP/nvptx_target_teams_distribute_parallel_for_codegen.cpp
+++ b/clang/test/OpenMP/nvptx_target_teams_distribute_parallel_for_codegen.cpp
@@ -93,8 +93,8 @@ int bar(int n){
 }
 
 // SEQ-DAG: [[MEM_TY:%.+]] = type { [128 x i8] }
-// SEQ-DAG: [[SHARED_GLOBAL_RD:@.+]] = common addrspace(3) global [[MEM_TY]] zeroinitializer
-// SEQ-DAG: [[KERNEL_PTR:@.+]] = internal addrspace(3) global i8* null
+// SEQ-DAG: [[SHARED_GLOBAL_RD:@.+]] = weak addrspace(3) global [[MEM_TY]] undef
+// SEQ-DAG: [[KERNEL_PTR:@.+]] = internal addrspace(3) global i8* undef
 // SEQ-DAG: [[KERNEL_SIZE:@.+]] = internal unnamed_addr constant i{{64|32}} 4
 // SEQ-DAG: [[KERNEL_SHARED:@.+]] = internal unnamed_addr constant i16 1
 

diff --git a/clang/test/OpenMP/nvptx_target_teams_distribute_parallel_for_simd_codegen.cpp b/clang/test/OpenMP/nvptx_target_teams_distribute_parallel_for_simd_codegen.cpp
index e9126fc..79af94a 100644 (file)
--- a/clang/test/OpenMP/nvptx_target_teams_distribute_parallel_for_simd_codegen.cpp
+++ b/clang/test/OpenMP/nvptx_target_teams_distribute_parallel_for_simd_codegen.cpp
@@ -76,8 +76,8 @@ int bar(int n){
 }
 
 // SEQ-DAG: [[MEM_TY:%.+]] = type { [128 x i8] }
-// SEQ-DAG: [[SHARED_GLOBAL_RD:@.+]] = common addrspace(3) global [[MEM_TY]] zeroinitializer
-// SEQ-DAG: [[KERNEL_PTR:@.+]] = internal addrspace(3) global i8* null
+// SEQ-DAG: [[SHARED_GLOBAL_RD:@.+]] = weak addrspace(3) global [[MEM_TY]] undef
+// SEQ-DAG: [[KERNEL_PTR:@.+]] = internal addrspace(3) global i8* undef
 // SEQ-DAG: [[KERNEL_SIZE:@.+]] = internal unnamed_addr constant i{{64|32}} 4
 // SEQ-DAG: [[KERNEL_SHARED:@.+]] = internal unnamed_addr constant i16 1
 

diff --git a/clang/test/OpenMP/nvptx_teams_codegen.cpp b/clang/test/OpenMP/nvptx_teams_codegen.cpp
index 36bb972..ac08cca 100644 (file)
--- a/clang/test/OpenMP/nvptx_teams_codegen.cpp
+++ b/clang/test/OpenMP/nvptx_teams_codegen.cpp
@@ -30,8 +30,8 @@ int main (int argc, char **argv) {
 }
 
 // SEQ: [[MEM_TY:%.+]] = type { [128 x i8] }
-// SEQ-DAG: [[SHARED_GLOBAL_RD:@.+]] = common addrspace(3) global [[MEM_TY]] zeroinitializer
-// SEQ-DAG: [[KERNEL_PTR:@.+]] = internal addrspace(3) global i8* null
+// SEQ-DAG: [[SHARED_GLOBAL_RD:@.+]] = weak addrspace(3) global [[MEM_TY]] undef
+// SEQ-DAG: [[KERNEL_PTR:@.+]] = internal addrspace(3) global i8* undef
 // SEQ-DAG: [[KERNEL_SIZE1:@.+]] = internal unnamed_addr constant i{{64|32}} 4
 // SEQ-DAG: [[KERNEL_SIZE2:@.+]] = internal unnamed_addr constant i{{64|32}} {{8|4}}
 // SEQ-DAG: [[KERNEL_SHARED1:@.+]] = internal unnamed_addr constant i16 1
@@ -119,8 +119,8 @@ int main (int argc, char **argv) {
 }
 
 // SEQ2: [[MEM_TY:%.+]] = type { [128 x i8] }
-// SEQ2-DAG: [[SHARED_GLOBAL_RD:@.+]] = common addrspace(3) global [[MEM_TY]] zeroinitializer
-// SEQ2-DAG: [[KERNEL_PTR:@.+]] = internal addrspace(3) global i8* null
+// SEQ2-DAG: [[SHARED_GLOBAL_RD:@.+]] = weak addrspace(3) global [[MEM_TY]] undef
+// SEQ2-DAG: [[KERNEL_PTR:@.+]] = internal addrspace(3) global i8* undef
 // SEQ2-DAG: [[KERNEL_SIZE1:@.+]] = internal unnamed_addr constant i{{64|32}} 4
 // SEQ2-DAG: [[KERNEL_SIZE2:@.+]] = internal unnamed_addr constant i{{64|32}} {{8|4}}
 // SEQ2-DAG: [[KERNEL_SHARED1:@.+]] = internal unnamed_addr constant i16 1

diff --git a/clang/test/OpenMP/nvptx_teams_reduction_codegen.cpp b/clang/test/OpenMP/nvptx_teams_reduction_codegen.cpp
index 5aa3e19..507b2f8 100644 (file)
--- a/clang/test/OpenMP/nvptx_teams_reduction_codegen.cpp
+++ b/clang/test/OpenMP/nvptx_teams_reduction_codegen.cpp
@@ -17,14 +17,14 @@
 // CHECK-DAG: [[TEAMS_REDUCE_UNION_TY:%.+]] = type { [[TEAM1_REDUCE_TY]] }
 // SEQ-DAG: [[MAP_TY:%.+]] = type { [128 x i8] }
 
-// SEQ-DAG: [[KERNEL_PTR:@.+]] = internal addrspace(3) global i8* null
+// SEQ-DAG: [[KERNEL_PTR:@.+]] = internal addrspace(3) global i8* undef
 // SEQ-DAG: [[KERNEL_SHARED1:@.+]] = internal unnamed_addr constant i16 1
 // SEQ-DAG: [[KERNEL_SHARED2:@.+]] = internal unnamed_addr constant i16 1
 // SEQ-DAG: [[KERNEL_SIZE1:@.+]] = internal unnamed_addr constant i{{64|32}} {{16|8}}
 // SEQ-DAG: [[KERNEL_SIZE2:@.+]] = internal unnamed_addr constant i{{64|32}} 16
 
 // Check for the data transfer medium in shared memory to transfer the reduction list to the first warp.
-// CHECK-DAG: [[TRANSFER_STORAGE:@.+]] = common addrspace([[SHARED_ADDRSPACE:[0-9]+]]) global [32 x i32]
+// CHECK-DAG: [[TRANSFER_STORAGE:@.+]] = weak addrspace([[SHARED_ADDRSPACE:[0-9]+]]) global [32 x i32]
 
 // Check that the execution mode of 2 target regions is set to Non-SPMD and the 3rd is in SPMD.
 // CHECK-DAG: {{@__omp_offloading_.+l44}}_exec_mode = weak constant i8 1