4 files changed, 44 insertions, 8 deletions
diff --git a/clang/lib/CodeGen/CGOpenMPRuntime.cpp b/clang/lib/CodeGen/CGOpenMPRuntime.cpp
index 4d9f495c16e..168504ccaf7 100644
--- a/clang/lib/CodeGen/CGOpenMPRuntime.cpp
+++ b/clang/lib/CodeGen/CGOpenMPRuntime.cpp
@@ -8106,7 +8106,12 @@ bool CGOpenMPRuntime::emitTargetGlobalVariable(GlobalDecl GD) {
   // Do not to emit variable if it is not marked as declare target.
   llvm::Optional<OMPDeclareTargetDeclAttr::MapTypeTy> Res =
       isDeclareTargetDeclaration(cast<VarDecl>(GD.getDecl()));
-  return !Res || *Res == OMPDeclareTargetDeclAttr::MT_Link;
+  if (!Res || *Res == OMPDeclareTargetDeclAttr::MT_Link) {
+    if (CGM.getContext().DeclMustBeEmitted(GD.getDecl()))
+      DeferredGlobalVariables.insert(cast<VarDecl>(GD.getDecl()));
+    return true;
+  }
+  return false;
 }
 
 void CGOpenMPRuntime::registerTargetGlobalVariable(const VarDecl *VD,
@@ -8163,6 +8168,18 @@ bool CGOpenMPRuntime::emitTargetGlobal(GlobalDecl GD) {
   return emitTargetGlobalVariable(GD);
 }
 
+void CGOpenMPRuntime::emitDeferredTargetDecls() const {
+  for (const VarDecl *VD : DeferredGlobalVariables) {
+    llvm::Optional<OMPDeclareTargetDeclAttr::MapTypeTy> Res =
+        isDeclareTargetDeclaration(VD);
+    if (Res) {
+      assert(*Res != OMPDeclareTargetDeclAttr::MT_Link &&
+             "Implicit declare target variables must be only to().");
+      CGM.EmitGlobal(VD);
+    }
+  }
+}
+
 CGOpenMPRuntime::DisableAutoDeclareTargetRAII::DisableAutoDeclareTargetRAII(
     CodeGenModule &CGM)
     : CGM(CGM) {
diff --git a/clang/lib/CodeGen/CGOpenMPRuntime.h b/clang/lib/CodeGen/CGOpenMPRuntime.h
index 01ff0c20fd6..ed2b56b5448 100644
--- a/clang/lib/CodeGen/CGOpenMPRuntime.h
+++ b/clang/lib/CodeGen/CGOpenMPRuntime.h
@@ -602,6 +602,10 @@ private:
   bool ShouldMarkAsGlobal = true;
   llvm::SmallDenseSet<const FunctionDecl *> AlreadyEmittedTargetFunctions;
 
+  /// List of variables that can become declare target implicitly and, thus,
+  /// must be emitted.
+  llvm::SmallDenseSet<const VarDecl *> DeferredGlobalVariables;
+
   /// Creates and registers offloading binary descriptor for the current
   /// compilation unit. The function that does the registration is returned.
   llvm::Function *createOffloadingBinaryDescriptorRegistration();
@@ -1509,6 +1513,8 @@ public:
   /// true, if it was marked already, and false, otherwise.
   bool markAsGlobalTarget(GlobalDecl GD);
 
+  /// Emit deferred declare target variables marked for deferred emission.
+  void emitDeferredTargetDecls() const;
 };
 
 /// Class supports emissionof SIMD-only code.
diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index 8c5e0df0969..dedd57efbd9 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -1747,6 +1747,10 @@ void CodeGenModule::EmitModuleLinkOptions() {
 }
 
 void CodeGenModule::EmitDeferred() {
+  // Emit deferred declare target declarations.
+  if (getLangOpts().OpenMP && !getLangOpts().OpenMPSimd)
+    getOpenMPRuntime().emitDeferredTargetDecls();
+
   // Emit code for any potentially referenced deferred decls.  Since a
   // previously unused static decl may become used during the generation of code
   // for a static function, iterate until no changes are made.
diff --git a/clang/lib/Sema/SemaOpenMP.cpp b/clang/lib/Sema/SemaOpenMP.cpp
index e1a4c420d40..0b1c3308208 100644
--- a/clang/lib/Sema/SemaOpenMP.cpp
+++ b/clang/lib/Sema/SemaOpenMP.cpp
@@ -1417,7 +1417,7 @@ bool Sema::isInOpenMPTargetExecutionDirective() const {
              false);
 }
 
-VarDecl *Sema::isOpenMPCapturedDecl(ValueDecl *D) const {
+VarDecl *Sema::isOpenMPCapturedDecl(ValueDecl *D) {
   assert(LangOpts.OpenMP && "OpenMP is not allowed");
   D = getCanonicalDecl(D);
 
@@ -1425,13 +1425,22 @@ VarDecl *Sema::isOpenMPCapturedDecl(ValueDecl *D) const {
   // 'target' we return true so that this global is also mapped to the device.
   //
   auto *VD = dyn_cast<VarDecl>(D);
-  if (VD && !VD->hasLocalStorage() && isInOpenMPTargetExecutionDirective()) {
-    // If the declaration is enclosed in a 'declare target' directive,
-    // then it should not be captured.
-    //
-    if (isDeclareTargetDeclaration(VD))
+  if (VD && !VD->hasLocalStorage()) {
+    if (isInOpenMPDeclareTargetContext() &&
+        (getCurCapturedRegion() || getCurBlock() || getCurLambda())) {
+      // Try to mark variable as declare target if it is used in capturing
+      // regions.
+      if (!isDeclareTargetDeclaration(VD))
+        checkDeclIsAllowedInOpenMPTarget(nullptr, VD);
       return nullptr;
-    return VD;
+    } else if (isInOpenMPTargetExecutionDirective()) {
+      // If the declaration is enclosed in a 'declare target' directive,
+      // then it should not be captured.
+      //
+      if (isDeclareTargetDeclaration(VD))
+        return nullptr;
+      return VD;
+    }
   }
 
   if (DSAStack->getCurrentDirective() != OMPD_unknown &&