[OPENMP] Codegen for ctor|dtor of declare target variables.

When the declare target variables are emitted for the device,
constructors|destructors for these variables must emitted and registered
by the runtime in the offloading sections.

llvm-svn: 328705

1 files changed, 164 insertions, 49 deletions

diff --git a/clang/lib/CodeGen/CGOpenMPRuntime.cpp b/clang/lib/CodeGen/CGOpenMPRuntime.cpp
index 891176b0097..4b1fac68277 100644
--- a/clang/lib/CodeGen/CGOpenMPRuntime.cpp
+++ b/clang/lib/CodeGen/CGOpenMPRuntime.cpp
@@ -2522,6 +2522,139 @@ llvm::Function *CGOpenMPRuntime::emitThreadPrivateVarDefinition(
   return nullptr;
 }
 
+/// \brief Obtain information that uniquely identifies a target entry. This
+/// consists of the file and device IDs as well as line number associated with
+/// the relevant entry source location.
+static void getTargetEntryUniqueInfo(ASTContext &C, SourceLocation Loc,
+                                     unsigned &DeviceID, unsigned &FileID,
+                                     unsigned &LineNum) {
+
+  auto &SM = C.getSourceManager();
+
+  // The loc should be always valid and have a file ID (the user cannot use
+  // #pragma directives in macros)
+
+  assert(Loc.isValid() && "Source location is expected to be always valid.");
+  assert(Loc.isFileID() && "Source location is expected to refer to a file.");
+
+  PresumedLoc PLoc = SM.getPresumedLoc(Loc);
+  assert(PLoc.isValid() && "Source location is expected to be always valid.");
+
+  llvm::sys::fs::UniqueID ID;
+  if (llvm::sys::fs::getUniqueID(PLoc.getFilename(), ID))
+    llvm_unreachable("Source file with target region no longer exists!");
+
+  DeviceID = ID.getDevice();
+  FileID = ID.getFile();
+  LineNum = PLoc.getLine();
+}
+
+bool CGOpenMPRuntime::emitDeclareTargetVarDefinition(const VarDecl *VD,
+                                                     llvm::GlobalVariable *Addr,
+                                                     bool PerformInit) {
+  Optional<OMPDeclareTargetDeclAttr::MapTypeTy> Res =
+      isDeclareTargetDeclaration(VD);
+  if (!Res || *Res == OMPDeclareTargetDeclAttr::MT_Link)
+    return false;
+  VD = VD->getDefinition(CGM.getContext());
+  if (VD && !DeclareTargetWithDefinition.insert(VD).second)
+    return CGM.getLangOpts().OpenMPIsDevice;
+
+  QualType ASTTy = VD->getType();
+
+  SourceLocation Loc = VD->getCanonicalDecl()->getLocStart();
+  // Produce the unique prefix to identify the new target regions. We use
+  // the source location of the variable declaration which we know to not
+  // conflict with any target region.
+  unsigned DeviceID;
+  unsigned FileID;
+  unsigned Line;
+  getTargetEntryUniqueInfo(CGM.getContext(), Loc, DeviceID, FileID, Line);
+  SmallString<128> Buffer, Out;
+  {
+    llvm::raw_svector_ostream OS(Buffer);
+    OS << "__omp_offloading_" << llvm::format("_%x", DeviceID)
+       << llvm::format("_%x_", FileID) << VD->getName() << "_l" << Line;
+  }
+
+  const Expr *Init = VD->getAnyInitializer();
+  if (CGM.getLangOpts().CPlusPlus && PerformInit) {
+    llvm::Constant *Ctor;
+    llvm::Constant *ID;
+    if (CGM.getLangOpts().OpenMPIsDevice) {
+      // Generate function that re-emits the declaration's initializer into
+      // the threadprivate copy of the variable VD
+      CodeGenFunction CtorCGF(CGM);
+
+      const CGFunctionInfo &FI = CGM.getTypes().arrangeNullaryFunction();
+      llvm::FunctionType *FTy = CGM.getTypes().GetFunctionType(FI);
+      llvm::Function *Fn = CGM.CreateGlobalInitOrDestructFunction(
+          FTy, Twine(Buffer, "_ctor"), FI, Loc);
+      auto NL = ApplyDebugLocation::CreateEmpty(CtorCGF);
+      CtorCGF.StartFunction(GlobalDecl(), CGM.getContext().VoidTy, Fn, FI,
+                            FunctionArgList(), Loc, Loc);
+      auto AL = ApplyDebugLocation::CreateArtificial(CtorCGF);
+      CtorCGF.EmitAnyExprToMem(Init,
+                               Address(Addr, CGM.getContext().getDeclAlign(VD)),
+                               Init->getType().getQualifiers(),
+                               /*IsInitializer=*/true);
+      CtorCGF.FinishFunction();
+      Ctor = Fn;
+      ID = llvm::ConstantExpr::getBitCast(Fn, CGM.Int8PtrTy);
+    } else {
+      Ctor = new llvm::GlobalVariable(
+          CGM.getModule(), CGM.Int8Ty, /*isConstant=*/true,
+          llvm::GlobalValue::PrivateLinkage,
+          llvm::Constant::getNullValue(CGM.Int8Ty), Twine(Buffer, "_ctor"));
+      ID = Ctor;
+    }
+
+    // Register the information for the entry associated with the constructor.
+    Out.clear();
+    OffloadEntriesInfoManager.registerTargetRegionEntryInfo(
+        DeviceID, FileID, Twine(Buffer, "_ctor").toStringRef(Out), Line, Ctor,
+        ID, OMPTargetRegionEntryCtor);
+  }
+  if (VD->getType().isDestructedType() != QualType::DK_none) {
+    llvm::Constant *Dtor;
+    llvm::Constant *ID;
+    if (CGM.getLangOpts().OpenMPIsDevice) {
+      // Generate function that emits destructor call for the threadprivate
+      // copy of the variable VD
+      CodeGenFunction DtorCGF(CGM);
+
+      const CGFunctionInfo &FI = CGM.getTypes().arrangeNullaryFunction();
+      llvm::FunctionType *FTy = CGM.getTypes().GetFunctionType(FI);
+      llvm::Function *Fn = CGM.CreateGlobalInitOrDestructFunction(
+          FTy, Twine(Buffer, "_dtor"), FI, Loc);
+      auto NL = ApplyDebugLocation::CreateEmpty(DtorCGF);
+      DtorCGF.StartFunction(GlobalDecl(), CGM.getContext().VoidTy, Fn, FI,
+                            FunctionArgList(), Loc, Loc);
+      // Create a scope with an artificial location for the body of this
+      // function.
+      auto AL = ApplyDebugLocation::CreateArtificial(DtorCGF);
+      DtorCGF.emitDestroy(Address(Addr, CGM.getContext().getDeclAlign(VD)),
+                          ASTTy, DtorCGF.getDestroyer(ASTTy.isDestructedType()),
+                          DtorCGF.needsEHCleanup(ASTTy.isDestructedType()));
+      DtorCGF.FinishFunction();
+      Dtor = Fn;
+      ID = llvm::ConstantExpr::getBitCast(Fn, CGM.Int8PtrTy);
+    } else {
+      Dtor = new llvm::GlobalVariable(
+          CGM.getModule(), CGM.Int8Ty, /*isConstant=*/true,
+          llvm::GlobalValue::PrivateLinkage,
+          llvm::Constant::getNullValue(CGM.Int8Ty), Twine(Buffer, "_dtor"));
+      ID = Dtor;
+    }
+    // Register the information for the entry associated with the destructor.
+    Out.clear();
+    OffloadEntriesInfoManager.registerTargetRegionEntryInfo(
+        DeviceID, FileID, Twine(Buffer, "_dtor").toStringRef(Out), Line, Dtor,
+        ID, OMPTargetRegionEntryDtor);
+  }
+  return CGM.getLangOpts().OpenMPIsDevice;
+}
+
 Address CGOpenMPRuntime::getAddrOfArtificialThreadPrivate(CodeGenFunction &CGF,
                                                           QualType VarType,
                                                           StringRef Name) {
@@ -3375,7 +3508,7 @@ void CGOpenMPRuntime::OffloadEntriesInfoManagerTy::
                                              "code generation.");
   OffloadEntriesTargetRegion[DeviceID][FileID][ParentName][LineNum] =
       OffloadEntryInfoTargetRegion(Order, /*Addr=*/nullptr, /*ID=*/nullptr,
-                                   /*Flags=*/0);
+                                   OMPTargetRegionEntryTargetRegion);
   ++OffloadingEntriesNum;
 }
 
@@ -3383,7 +3516,7 @@ void CGOpenMPRuntime::OffloadEntriesInfoManagerTy::
     registerTargetRegionEntryInfo(unsigned DeviceID, unsigned FileID,
                                   StringRef ParentName, unsigned LineNum,
                                   llvm::Constant *Addr, llvm::Constant *ID,
-                                  int32_t Flags) {
+                                  OMPTargetRegionEntryKind Flags) {
   // If we are emitting code for a target, the entry is already initialized,
   // only has to be registered.
   if (CGM.getLangOpts().OpenMPIsDevice) {
@@ -3641,12 +3774,12 @@ void CGOpenMPRuntime::createOffloadEntriesAndInfoMetadata() {
   llvm::NamedMDNode *MD = M.getOrInsertNamedMetadata("omp_offload.info");
 
   // Auxiliary methods to create metadata values and strings.
-  auto getMDInt = [&](unsigned v) {
+  auto GetMdInt = [&C](unsigned V) {
     return llvm::ConstantAsMetadata::get(
-        llvm::ConstantInt::get(llvm::Type::getInt32Ty(C), v));
+        llvm::ConstantInt::get(llvm::Type::getInt32Ty(C), V));
   };
 
-  auto getMDString = [&](StringRef v) { return llvm::MDString::get(C, v); };
+  auto GetMdString = [&C](StringRef V) { return llvm::MDString::get(C, V); };
 
   // Create function that emits metadata for each target region entry;
   auto &&TargetRegionMetadataEmitter = [&](
@@ -3662,12 +3795,12 @@ void CGOpenMPRuntime::createOffloadEntriesAndInfoMetadata() {
     // - Entry 4 -> Line in the file where the entry was identified.
     // - Entry 5 -> Order the entry was created.
     // The first element of the metadata node is the kind.
-    Ops.push_back(getMDInt(E.getKind()));
-    Ops.push_back(getMDInt(DeviceID));
-    Ops.push_back(getMDInt(FileID));
-    Ops.push_back(getMDString(ParentName));
-    Ops.push_back(getMDInt(Line));
-    Ops.push_back(getMDInt(E.getOrder()));
+    Ops.push_back(GetMdInt(E.getKind()));
+    Ops.push_back(GetMdInt(DeviceID));
+    Ops.push_back(GetMdInt(FileID));
+    Ops.push_back(GetMdString(ParentName));
+    Ops.push_back(GetMdInt(Line));
+    Ops.push_back(GetMdInt(E.getOrder()));
 
     // Save this entry in the right position of the ordered entries array.
     OrderedEntries[E.getOrder()] = &E;
@@ -3686,7 +3819,8 @@ void CGOpenMPRuntime::createOffloadEntriesAndInfoMetadata() {
                 E)) {
       assert(CE->getID() && CE->getAddress() &&
              "Entry ID and Addr are invalid!");
-      createOffloadEntry(CE->getID(), CE->getAddress(), /*Size=*/0);
+      createOffloadEntry(CE->getID(), CE->getAddress(), /*Size=*/0,
+                         CE->getFlags());
     } else
       llvm_unreachable("Unsupported entry kind.");
   }
@@ -3720,27 +3854,27 @@ void CGOpenMPRuntime::loadOffloadInfoMetadata() {
     return;
 
   for (llvm::MDNode *MN : MD->operands()) {
-    auto getMDInt = [&](unsigned Idx) {
+    auto GetMdInt = [MN](unsigned Idx) {
       llvm::ConstantAsMetadata *V =
           cast<llvm::ConstantAsMetadata>(MN->getOperand(Idx));
       return cast<llvm::ConstantInt>(V->getValue())->getZExtValue();
     };
 
-    auto getMDString = [&](unsigned Idx) {
+    auto GetMdString = [MN](unsigned Idx) {
       llvm::MDString *V = cast<llvm::MDString>(MN->getOperand(Idx));
       return V->getString();
     };
 
-    switch (getMDInt(0)) {
+    switch (GetMdInt(0)) {
     default:
       llvm_unreachable("Unexpected metadata!");
       break;
     case OffloadEntriesInfoManagerTy::OffloadEntryInfo::
-        OFFLOAD_ENTRY_INFO_TARGET_REGION:
+        OffloadingEntryInfoTargetRegion:
       OffloadEntriesInfoManager.initializeTargetRegionEntryInfo(
-          /*DeviceID=*/getMDInt(1), /*FileID=*/getMDInt(2),
-          /*ParentName=*/getMDString(3), /*Line=*/getMDInt(4),
-          /*Order=*/getMDInt(5));
+          /*DeviceID=*/GetMdInt(1), /*FileID=*/GetMdInt(2),
+          /*ParentName=*/GetMdString(3), /*Line=*/GetMdInt(4),
+          /*Order=*/GetMdInt(5));
       break;
     }
   }
@@ -5871,33 +6005,6 @@ void CGOpenMPRuntime::emitCancelCall(CodeGenFunction &CGF, SourceLocation Loc,
   }
 }
 
-/// \brief Obtain information that uniquely identifies a target entry. This
-/// consists of the file and device IDs as well as line number associated with
-/// the relevant entry source location.
-static void getTargetEntryUniqueInfo(ASTContext &C, SourceLocation Loc,
-                                     unsigned &DeviceID, unsigned &FileID,
-                                     unsigned &LineNum) {
-
-  auto &SM = C.getSourceManager();
-
-  // The loc should be always valid and have a file ID (the user cannot use
-  // #pragma directives in macros)
-
-  assert(Loc.isValid() && "Source location is expected to be always valid.");
-  assert(Loc.isFileID() && "Source location is expected to refer to a file.");
-
-  PresumedLoc PLoc = SM.getPresumedLoc(Loc);
-  assert(PLoc.isValid() && "Source location is expected to be always valid.");
-
-  llvm::sys::fs::UniqueID ID;
-  if (llvm::sys::fs::getUniqueID(PLoc.getFilename(), ID))
-    llvm_unreachable("Source file with target region no longer exists!");
-
-  DeviceID = ID.getDevice();
-  FileID = ID.getFile();
-  LineNum = PLoc.getLine();
-}
-
 void CGOpenMPRuntime::emitTargetOutlinedFunction(
     const OMPExecutableDirective &D, StringRef ParentName,
     llvm::Function *&OutlinedFn, llvm::Constant *&OutlinedFnID,
@@ -5970,7 +6077,7 @@ void CGOpenMPRuntime::emitTargetOutlinedFunctionHelper(
   // Register the information for the entry associated with this target region.
   OffloadEntriesInfoManager.registerTargetRegionEntryInfo(
       DeviceID, FileID, ParentName, Line, OutlinedFn, OutlinedFnID,
-      /*Flags=*/0);
+      OMPTargetRegionEntryTargetRegion);
 }
 
 /// discard all CompoundStmts intervening between two constructs
@@ -7530,12 +7637,20 @@ CGOpenMPRuntime::DisableAutoDeclareTargetRAII::~DisableAutoDeclareTargetRAII() {
 bool CGOpenMPRuntime::markAsGlobalTarget(const FunctionDecl *D) {
   if (!CGM.getLangOpts().OpenMPIsDevice || !ShouldMarkAsGlobal)
     return true;
+
+  const FunctionDecl *FD = D->getCanonicalDecl();
   // Do not to emit function if it is marked as declare target as it was already
   // emitted.
-  if (isDeclareTargetDeclaration(D))
+  if (isDeclareTargetDeclaration(D)) {
+    if (D->hasBody() && AlreadyEmittedTargetFunctions.count(FD) == 0) {
+      if (auto *F = dyn_cast_or_null<llvm::Function>(
+              CGM.GetGlobalValue(CGM.getMangledName(D))))
+        return !F->isDeclaration();
+      return false;
+    }
     return true;
+  }
 
-  const FunctionDecl *FD = D->getCanonicalDecl();
   // Do not mark member functions except for static.
   if (const auto *Method = dyn_cast<CXXMethodDecl>(FD))
     if (!Method->isStatic())