[OpenMP] Make the exec_mode global have protected visibility

We use protected visibility for almost everything with offloading. This
is because it provides us with the ability to read things from the host
without the expectation that it will be preempted by a shared library
load, bugs related to this have happened when offloading to the host.
This patch just makes the `exec_mode` global generated for each plugin
have protected visibility.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D135285

5 files changed, 15 insertions, 14 deletions

diff --git a/clang/lib/CodeGen/CGOpenMPRuntimeGPU.cpp b/clang/lib/CodeGen/CGOpenMPRuntimeGPU.cpp
index a44d454f9f72..e3ef331e67ee 100644
--- a/clang/lib/CodeGen/CGOpenMPRuntimeGPU.cpp
+++ b/clang/lib/CodeGen/CGOpenMPRuntimeGPU.cpp
@@ -836,6 +836,7 @@ static void setPropertyExecutionMode(CodeGenModule &CGM, StringRef Name,
       llvm::ConstantInt::get(CGM.Int8Ty, Mode ? OMP_TGT_EXEC_MODE_SPMD
                                               : OMP_TGT_EXEC_MODE_GENERIC),
       Twine(Name, "_exec_mode"));
+  GVMode->setVisibility(llvm::GlobalVariable::ProtectedVisibility);
   CGM.addCompilerUsedGlobal(GVMode);
 }
 
diff --git a/clang/test/OpenMP/nvptx_target_parallel_proc_bind_codegen.cpp b/clang/test/OpenMP/nvptx_target_parallel_proc_bind_codegen.cpp
index 71d8d7757214..0f14d687bf79 100644
--- a/clang/test/OpenMP/nvptx_target_parallel_proc_bind_codegen.cpp
+++ b/clang/test/OpenMP/nvptx_target_parallel_proc_bind_codegen.cpp
@@ -16,9 +16,9 @@
 #define HEADER
 
 // Check that the execution mode of all 3 target regions on the gpu is set to SPMD Mode.
-// CHECK-DAG: {{@__omp_offloading_.+l29}}_exec_mode = weak constant i8 2
-// CHECK-DAG: {{@__omp_offloading_.+l33}}_exec_mode = weak constant i8 2
-// CHECK-DAG: {{@__omp_offloading_.+l38}}_exec_mode = weak constant i8 2
+// CHECK-DAG: {{@__omp_offloading_.+l29}}_exec_mode = weak protected constant i8 2
+// CHECK-DAG: {{@__omp_offloading_.+l33}}_exec_mode = weak protected constant i8 2
+// CHECK-DAG: {{@__omp_offloading_.+l38}}_exec_mode = weak protected constant i8 2
 
 template<typename tx>
 tx ftemplate(int n) {
diff --git a/clang/test/OpenMP/nvptx_target_parallel_reduction_codegen.cpp b/clang/test/OpenMP/nvptx_target_parallel_reduction_codegen.cpp
index 4bcf8063cadc..b103e21d01de 100644
--- a/clang/test/OpenMP/nvptx_target_parallel_reduction_codegen.cpp
+++ b/clang/test/OpenMP/nvptx_target_parallel_reduction_codegen.cpp
@@ -12,9 +12,9 @@
 // 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 2
-// CHECK-DAG: {{@__omp_offloading_.+l32}}_exec_mode = weak constant i8 2
-// CHECK-DAG: {{@__omp_offloading_.+l38}}_exec_mode = weak constant i8 2
+// CHECK-DAG: {{@__omp_offloading_.+l27}}_exec_mode = weak protected constant i8 2
+// CHECK-DAG: {{@__omp_offloading_.+l32}}_exec_mode = weak protected constant i8 2
+// CHECK-DAG: {{@__omp_offloading_.+l38}}_exec_mode = weak protected constant i8 2
 
 template<typename tx>
 tx ftemplate(int n) {
diff --git a/clang/test/OpenMP/nvptx_target_simd_codegen.cpp b/clang/test/OpenMP/nvptx_target_simd_codegen.cpp
index fadfa7f1821e..435ff7babd6c 100644
--- a/clang/test/OpenMP/nvptx_target_simd_codegen.cpp
+++ b/clang/test/OpenMP/nvptx_target_simd_codegen.cpp
@@ -16,10 +16,10 @@
 #define HEADER
 
 // Check that the execution mode of all 2 target regions on the gpu is set to NonSPMD Mode.
-// CHECK-DAG: {{@__omp_offloading_.+l32}}_exec_mode = weak constant i8 2
-// CHECK-DAG: {{@__omp_offloading_.+l37}}_exec_mode = weak constant i8 2
-// CHECK-DAG: {{@__omp_offloading_.+l42}}_exec_mode = weak constant i8 2
-// CHECK-DAG: {{@__omp_offloading_.+l47}}_exec_mode = weak constant i8 2
+// CHECK-DAG: {{@__omp_offloading_.+l32}}_exec_mode = weak protected constant i8 2
+// CHECK-DAG: {{@__omp_offloading_.+l37}}_exec_mode = weak protected constant i8 2
+// CHECK-DAG: {{@__omp_offloading_.+l42}}_exec_mode = weak protected constant i8 2
+// CHECK-DAG: {{@__omp_offloading_.+l47}}_exec_mode = weak protected constant i8 2
 
 #define N 1000
 
diff --git a/clang/test/OpenMP/nvptx_target_teams_distribute_simd_codegen.cpp b/clang/test/OpenMP/nvptx_target_teams_distribute_simd_codegen.cpp
index fed8226ae62e..cb177df6c5fd 100644
--- a/clang/test/OpenMP/nvptx_target_teams_distribute_simd_codegen.cpp
+++ b/clang/test/OpenMP/nvptx_target_teams_distribute_simd_codegen.cpp
@@ -16,10 +16,10 @@
 #define HEADER
 
 // Check that the execution mode of all 2 target regions on the gpu is set to NonSPMD Mode.
-// CHECK-DAG: {{@__omp_offloading_.+l37}}_exec_mode = weak constant i8 2
-// CHECK-DAG: {{@__omp_offloading_.+l43}}_exec_mode = weak constant i8 2
-// CHECK-DAG: {{@__omp_offloading_.+l48}}_exec_mode = weak constant i8 2
-// CHECK-DAG: {{@__omp_offloading_.+l53}}_exec_mode = weak constant i8 2
+// CHECK-DAG: {{@__omp_offloading_.+l37}}_exec_mode = weak protected constant i8 2
+// CHECK-DAG: {{@__omp_offloading_.+l43}}_exec_mode = weak protected constant i8 2
+// CHECK-DAG: {{@__omp_offloading_.+l48}}_exec_mode = weak protected constant i8 2
+// CHECK-DAG: {{@__omp_offloading_.+l53}}_exec_mode = weak protected constant i8 2
 
 #define N 1000
 #define M 10