[OpenMP] Reapply rL256842: [OpenMP] Offloading descriptor registration and device codegen.

This patch attempts to fix the regressions identified when the patch was committed initially. 

Thanks to Michael Liao for identifying the fix in the offloading metadata generation 
related with side effects in evaluation of function arguments. 
 

llvm-svn: 256933

1 files changed, 12 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index 173b0dcba1c..f57785f6b58 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -375,6 +375,10 @@ void CodeGenModule::Release() {
     if (llvm::Function *CudaDtorFunction = CUDARuntime->makeModuleDtorFunction())
       AddGlobalDtor(CudaDtorFunction);
   }
+  if (OpenMPRuntime)
+    if (llvm::Function *OpenMPRegistrationFunction =
+            OpenMPRuntime->emitRegistrationFunction())
+      AddGlobalCtor(OpenMPRegistrationFunction, 0);
   if (PGOReader) {
     getModule().setMaximumFunctionCount(PGOReader->getMaximumFunctionCount());
     if (PGOStats.hasDiagnostics())
@@ -1490,6 +1494,11 @@ void CodeGenModule::EmitGlobal(GlobalDecl GD) {
     }
   }
 
+  // If this is OpenMP device, check if it is legal to emit this global
+  // normally.
+  if (OpenMPRuntime && OpenMPRuntime->emitTargetGlobal(GD))
+    return;
+
   // Ignore declarations, they will be emitted on their first use.
   if (const auto *FD = dyn_cast<FunctionDecl>(Global)) {
     // Forward declarations are emitted lazily on first use.
@@ -3596,6 +3605,9 @@ void CodeGenModule::EmitTopLevelDecl(Decl *D) {
     // File-scope asm is ignored during device-side CUDA compilation.
     if (LangOpts.CUDA && LangOpts.CUDAIsDevice)
       break;
+    // File-scope asm is ignored during device-side OpenMP compilation.
+    if (LangOpts.OpenMPIsDevice)
+      break;
     auto *AD = cast<FileScopeAsmDecl>(D);
     getModule().appendModuleInlineAsm(AD->getAsmString()->getString());
     break;