[OPENMP 4.5] Allow arrays in 'reduction' clause.

OpenMP 4.5, alogn with array sections, allows to use variables of array type in reductions.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@258804 91177308-0d34-0410-b5e6-96231b3b80d8

4 files changed, 114 insertions, 81 deletions

diff --git a/lib/CodeGen/CGOpenMPRuntime.cpp b/lib/CodeGen/CGOpenMPRuntime.cpp
index 5cfacacbe0..6aa2737cba 100644
--- a/lib/CodeGen/CGOpenMPRuntime.cpp
+++ b/lib/CodeGen/CGOpenMPRuntime.cpp
@@ -967,26 +967,6 @@ CGOpenMPRuntime::createRuntimeFunction(OpenMPRTLFunction Function) {
   return RTLFn;
 }
 
-static llvm::Value *getTypeSize(CodeGenFunction &CGF, QualType Ty) {
-  auto &C = CGF.getContext();
-  llvm::Value *Size = nullptr;
-  auto SizeInChars = C.getTypeSizeInChars(Ty);
-  if (SizeInChars.isZero()) {
-    // getTypeSizeInChars() returns 0 for a VLA.
-    while (auto *VAT = C.getAsVariableArrayType(Ty)) {
-      llvm::Value *ArraySize;
-      std::tie(ArraySize, Ty) = CGF.getVLASize(VAT);
-      Size = Size ? CGF.Builder.CreateNUWMul(Size, ArraySize) : ArraySize;
-    }
-    SizeInChars = C.getTypeSizeInChars(Ty);
-    assert(!SizeInChars.isZero());
-    Size = CGF.Builder.CreateNUWMul(
-        Size, llvm::ConstantInt::get(CGF.SizeTy, SizeInChars.getQuantity()));
-  } else
-    Size = llvm::ConstantInt::get(CGF.SizeTy, SizeInChars.getQuantity());
-  return Size;
-}
-
 llvm::Constant *CGOpenMPRuntime::createForStaticInitFunction(unsigned IVSize,
                                                              bool IVSigned) {
   assert((IVSize == 32 || IVSize == 64) &&
@@ -1655,7 +1635,7 @@ void CGOpenMPRuntime::emitSingleRegion(CodeGenFunction &CGF,
     auto *CpyFn = emitCopyprivateCopyFunction(
         CGM, CGF.ConvertTypeForMem(CopyprivateArrayTy)->getPointerTo(),
         CopyprivateVars, SrcExprs, DstExprs, AssignmentOps);
-    auto *BufSize = getTypeSize(CGF, CopyprivateArrayTy);
+    auto *BufSize = CGF.getTypeSize(CopyprivateArrayTy);
     Address CL =
       CGF.Builder.CreatePointerBitCastOrAddrSpaceCast(CopyprivateList,
                                                       CGF.VoidPtrTy);
@@ -2806,7 +2786,7 @@ void CGOpenMPRuntime::emitTaskCall(
       C.getPointerType(KmpTaskTWithPrivatesQTy);
   auto *KmpTaskTWithPrivatesTy = CGF.ConvertType(KmpTaskTWithPrivatesQTy);
   auto *KmpTaskTWithPrivatesPtrTy = KmpTaskTWithPrivatesTy->getPointerTo();
-  auto *KmpTaskTWithPrivatesTySize = getTypeSize(CGF, KmpTaskTWithPrivatesQTy);
+  auto *KmpTaskTWithPrivatesTySize = CGF.getTypeSize(KmpTaskTWithPrivatesQTy);
   QualType SharedsPtrTy = C.getPointerType(SharedsTy);
 
   // Emit initial values for private copies (if any).
@@ -3006,7 +2986,7 @@ void CGOpenMPRuntime::emitTaskCall(
         llvm::Value *UpIntPtr = CGF.Builder.CreatePtrToInt(UpAddr, CGM.SizeTy);
         Size = CGF.Builder.CreateNUWSub(UpIntPtr, LowIntPtr);
       } else
-        Size = getTypeSize(CGF, Ty);
+        Size = CGF.getTypeSize(Ty);
       auto Base = CGF.MakeAddrLValue(
           CGF.Builder.CreateConstArrayGEP(DependenciesArray, i, DependencySize),
           KmpDependInfoTy);
@@ -3255,17 +3235,16 @@ static llvm::Value *emitReductionFunction(CodeGenModule &CGM,
       return emitAddrOfVarFromArray(CGF, LHS, Idx, LHSVar);
     });
     QualType PrivTy = (*IPriv)->getType();
-    if (PrivTy->isArrayType()) {
+    if (PrivTy->isVariablyModifiedType()) {
       // Get array size and emit VLA type.
       ++Idx;
       Address Elem =
           CGF.Builder.CreateConstArrayGEP(LHS, Idx, CGF.getPointerSize());
       llvm::Value *Ptr = CGF.Builder.CreateLoad(Elem);
+      auto *VLA = CGF.getContext().getAsVariableArrayType(PrivTy);
+      auto *OVE = cast<OpaqueValueExpr>(VLA->getSizeExpr());
       CodeGenFunction::OpaqueValueMapping OpaqueMap(
-          CGF,
-          cast<OpaqueValueExpr>(
-              CGF.getContext().getAsVariableArrayType(PrivTy)->getSizeExpr()),
-          RValue::get(CGF.Builder.CreatePtrToInt(Ptr, CGF.SizeTy)));
+          CGF, OVE, RValue::get(CGF.Builder.CreatePtrToInt(Ptr, CGF.SizeTy)));
       CGF.EmitVariablyModifiedType(PrivTy);
     }
   }
@@ -3361,7 +3340,7 @@ void CGOpenMPRuntime::emitReduction(CodeGenFunction &CGF, SourceLocation Loc,
   // void *RedList[<n>] = {<ReductionVars>[0], ..., <ReductionVars>[<n>-1]};
   auto Size = RHSExprs.size();
   for (auto *E : Privates) {
-    if (E->getType()->isArrayType())
+    if (E->getType()->isVariablyModifiedType())
       // Reserve place for array size.
       ++Size;
   }
@@ -3380,20 +3359,18 @@ void CGOpenMPRuntime::emitReduction(CodeGenFunction &CGF, SourceLocation Loc,
         CGF.Builder.CreatePointerBitCastOrAddrSpaceCast(
             CGF.EmitLValue(RHSExprs[I]).getPointer(), CGF.VoidPtrTy),
         Elem);
-    if ((*IPriv)->getType()->isArrayType()) {
+    if ((*IPriv)->getType()->isVariablyModifiedType()) {
       // Store array size.
       ++Idx;
       Elem = CGF.Builder.CreateConstArrayGEP(ReductionList, Idx,
                                              CGF.getPointerSize());
-      CGF.Builder.CreateStore(
-          CGF.Builder.CreateIntToPtr(
-              CGF.Builder.CreateIntCast(
-                  CGF.getVLASize(CGF.getContext().getAsVariableArrayType(
-                                     (*IPriv)->getType()))
-                      .first,
-                  CGF.SizeTy, /*isSigned=*/false),
-              CGF.VoidPtrTy),
-          Elem);
+      llvm::Value *Size = CGF.Builder.CreateIntCast(
+          CGF.getVLASize(
+                 CGF.getContext().getAsVariableArrayType((*IPriv)->getType()))
+              .first,
+          CGF.SizeTy, /*isSigned=*/false);
+      CGF.Builder.CreateStore(CGF.Builder.CreateIntToPtr(Size, CGF.VoidPtrTy),
+                              Elem);
     }
   }
 
@@ -3411,7 +3388,7 @@ void CGOpenMPRuntime::emitReduction(CodeGenFunction &CGF, SourceLocation Loc,
       CGF, Loc,
       static_cast<OpenMPLocationFlags>(OMP_IDENT_KMPC | OMP_ATOMIC_REDUCE));
   auto *ThreadId = getThreadID(CGF, Loc);
-  auto *ReductionArrayTySize = getTypeSize(CGF, ReductionArrayTy);
+  auto *ReductionArrayTySize = CGF.getTypeSize(ReductionArrayTy);
   auto *RL =
     CGF.Builder.CreatePointerBitCastOrAddrSpaceCast(ReductionList.getPointer(),
                                                     CGF.VoidPtrTy);
@@ -3873,14 +3850,14 @@ void CGOpenMPRuntime::emitTargetCall(CodeGenFunction &CGF,
     // VLA sizes are passed to the outlined region by copy.
     if (CI->capturesVariableArrayType()) {
       BasePointer = Pointer = *CV;
-      Size = getTypeSize(CGF, RI->getType());
+      Size = CGF.getTypeSize(RI->getType());
       // Copy to the device as an argument. No need to retrieve it.
       MapType = OMP_MAP_BYCOPY;
       hasVLACaptures = true;
     } else if (CI->capturesThis()) {
       BasePointer = Pointer = *CV;
       const PointerType *PtrTy = cast<PointerType>(RI->getType().getTypePtr());
-      Size = getTypeSize(CGF, PtrTy->getPointeeType());
+      Size = CGF.getTypeSize(PtrTy->getPointeeType());
       // Default map type.
       MapType = OMP_MAP_TO | OMP_MAP_FROM;
     } else if (CI->capturesVariableByCopy()) {
@@ -3909,7 +3886,7 @@ void CGOpenMPRuntime::emitTargetCall(CodeGenFunction &CGF,
         MapType |= OMP_MAP_PTR;
         BasePointer = Pointer = *CV;
       }
-      Size = getTypeSize(CGF, RI->getType());
+      Size = CGF.getTypeSize(RI->getType());
     } else {
       assert(CI->capturesVariable() && "Expected captured reference.");
       BasePointer = Pointer = *CV;
@@ -3917,7 +3894,7 @@ void CGOpenMPRuntime::emitTargetCall(CodeGenFunction &CGF,
       const ReferenceType *PtrTy =
           cast<ReferenceType>(RI->getType().getTypePtr());
       QualType ElementType = PtrTy->getPointeeType();
-      Size = getTypeSize(CGF, ElementType);
+      Size = CGF.getTypeSize(ElementType);
       // The default map type for a scalar/complex type is 'to' because by
       // default the value doesn't have to be retrieved. For an aggregate type,
       // the default is 'tofrom'.
diff --git a/lib/CodeGen/CGStmtOpenMP.cpp b/lib/CodeGen/CGStmtOpenMP.cpp
index 42899fcb81..a6abbba934 100644
--- a/lib/CodeGen/CGStmtOpenMP.cpp
+++ b/lib/CodeGen/CGStmtOpenMP.cpp
@@ -20,6 +20,26 @@
 using namespace clang;
 using namespace CodeGen;
 
+llvm::Value *CodeGenFunction::getTypeSize(QualType Ty) {
+  auto &C = getContext();
+  llvm::Value *Size = nullptr;
+  auto SizeInChars = C.getTypeSizeInChars(Ty);
+  if (SizeInChars.isZero()) {
+    // getTypeSizeInChars() returns 0 for a VLA.
+    while (auto *VAT = C.getAsVariableArrayType(Ty)) {
+      llvm::Value *ArraySize;
+      std::tie(ArraySize, Ty) = getVLASize(VAT);
+      Size = Size ? Builder.CreateNUWMul(Size, ArraySize) : ArraySize;
+    }
+    SizeInChars = C.getTypeSizeInChars(Ty);
+    if (SizeInChars.isZero())
+      return llvm::ConstantInt::get(SizeTy, /*V=*/0);
+    Size = Builder.CreateNUWMul(Size, CGM.getSize(SizeInChars));
+  } else
+    Size = CGM.getSize(SizeInChars);
+  return Size;
+}
+
 void CodeGenFunction::GenerateOpenMPCapturedVars(
     const CapturedStmt &S, SmallVectorImpl<llvm::Value *> &CapturedVars) {
   const RecordDecl *RD = S.getCapturedRecordDecl();
@@ -779,32 +799,76 @@ void CodeGenFunction::EmitOMPReductionClauseInit(
         assert(IsRegistered && "private var already registered as private");
         // Silence the warning about unused variable.
         (void)IsRegistered;
-        PrivateScope.addPrivate(RHSVD, [this, PrivateVD]() -> Address {
-          return GetAddrOfLocalVar(PrivateVD);
+        PrivateScope.addPrivate(RHSVD, [this, PrivateVD, RHSVD]() -> Address {
+          return Builder.CreateElementBitCast(
+              GetAddrOfLocalVar(PrivateVD), ConvertTypeForMem(RHSVD->getType()),
+              "rhs.begin");
         });
       } else {
         auto *OrigVD = cast<VarDecl>(cast<DeclRefExpr>(IRef)->getDecl());
-        // Store the address of the original variable associated with the LHS
-        // implicit variable.
-        PrivateScope.addPrivate(LHSVD, [this, OrigVD, IRef]() -> Address {
+        QualType Type = PrivateVD->getType();
+        if (getContext().getAsArrayType(Type)) {
+          // Store the address of the original variable associated with the LHS
+          // implicit variable.
           DeclRefExpr DRE(const_cast<VarDecl *>(OrigVD),
                           CapturedStmtInfo->lookup(OrigVD) != nullptr,
                           IRef->getType(), VK_LValue, IRef->getExprLoc());
-          return EmitLValue(&DRE).getAddress();
-        });
-        // Emit reduction copy.
-        bool IsRegistered =
-            PrivateScope.addPrivate(OrigVD, [this, PrivateVD]() -> Address {
-              // Emit private VarDecl with reduction init.
-              EmitDecl(*PrivateVD);
-              return GetAddrOfLocalVar(PrivateVD);
-            });
-        assert(IsRegistered && "private var already registered as private");
-        // Silence the warning about unused variable.
-        (void)IsRegistered;
-        PrivateScope.addPrivate(RHSVD, [this, PrivateVD]() -> Address {
-          return GetAddrOfLocalVar(PrivateVD);
-        });
+          Address OriginalAddr = EmitLValue(&DRE).getAddress();
+          PrivateScope.addPrivate(LHSVD, [this, OriginalAddr,
+                                          LHSVD]() -> Address {
+            return Builder.CreateElementBitCast(
+                OriginalAddr, ConvertTypeForMem(LHSVD->getType()),
+                "lhs.begin");
+          });
+          bool IsRegistered = PrivateScope.addPrivate(OrigVD, [&]() -> Address {
+            if (Type->isVariablyModifiedType()) {
+              CodeGenFunction::OpaqueValueMapping OpaqueMap(
+                  *this, cast<OpaqueValueExpr>(
+                             getContext()
+                                 .getAsVariableArrayType(PrivateVD->getType())
+                                 ->getSizeExpr()),
+                  RValue::get(
+                      getTypeSize(OrigVD->getType().getNonReferenceType())));
+              EmitVariablyModifiedType(Type);
+            }
+            auto Emission = EmitAutoVarAlloca(*PrivateVD);
+            auto Addr = Emission.getAllocatedAddress();
+            auto *Init = PrivateVD->getInit();
+            EmitOMPAggregateInit(*this, Addr, PrivateVD->getType(), Init);
+            EmitAutoVarCleanups(Emission);
+            return Emission.getAllocatedAddress();
+          });
+          assert(IsRegistered && "private var already registered as private");
+          // Silence the warning about unused variable.
+          (void)IsRegistered;
+          PrivateScope.addPrivate(RHSVD, [this, PrivateVD, RHSVD]() -> Address {
+            return Builder.CreateElementBitCast(
+                GetAddrOfLocalVar(PrivateVD),
+                ConvertTypeForMem(RHSVD->getType()), "rhs.begin");
+          });
+        } else {
+          // Store the address of the original variable associated with the LHS
+          // implicit variable.
+          PrivateScope.addPrivate(LHSVD, [this, OrigVD, IRef]() -> Address {
+            DeclRefExpr DRE(const_cast<VarDecl *>(OrigVD),
+                            CapturedStmtInfo->lookup(OrigVD) != nullptr,
+                            IRef->getType(), VK_LValue, IRef->getExprLoc());
+            return EmitLValue(&DRE).getAddress();
+          });
+          // Emit reduction copy.
+          bool IsRegistered =
+              PrivateScope.addPrivate(OrigVD, [this, PrivateVD]() -> Address {
+                // Emit private VarDecl with reduction init.
+                EmitDecl(*PrivateVD);
+                return GetAddrOfLocalVar(PrivateVD);
+              });
+          assert(IsRegistered && "private var already registered as private");
+          // Silence the warning about unused variable.
+          (void)IsRegistered;
+          PrivateScope.addPrivate(RHSVD, [this, PrivateVD]() -> Address {
+            return GetAddrOfLocalVar(PrivateVD);
+          });
+        }
       }
       ++ILHS, ++IRHS, ++IPriv;
     }
diff --git a/lib/CodeGen/CodeGenFunction.h b/lib/CodeGen/CodeGenFunction.h
index bbfe82d5b5..10bec3910e 100644
--- a/lib/CodeGen/CodeGenFunction.h
+++ b/lib/CodeGen/CodeGenFunction.h
@@ -2206,6 +2206,8 @@ public:
   void EmitCXXForRangeStmt(const CXXForRangeStmt &S,
                            ArrayRef<const Attr *> Attrs = None);
 
+  /// Returns calculated size of the specified type.
+  llvm::Value *getTypeSize(QualType Ty);
   LValue InitCapturedStruct(const CapturedStmt &S);
   llvm::Function *EmitCapturedStmt(const CapturedStmt &S, CapturedRegionKind K);
   llvm::Function *GenerateCapturedStmtFunction(const CapturedStmt &S);
diff --git a/lib/Sema/SemaOpenMP.cpp b/lib/Sema/SemaOpenMP.cpp
index 6272a6284e..d9ea8fb0cc 100644
--- a/lib/Sema/SemaOpenMP.cpp
+++ b/lib/Sema/SemaOpenMP.cpp
@@ -7469,7 +7469,7 @@ OMPClause *Sema::ActOnOpenMPReductionClause(
     if (DE) {
       auto D = DE->getDecl();
       VD = cast<VarDecl>(D);
-      Type = VD->getType();
+      Type = Context.getBaseElementType(VD->getType());
     } else if (ASE) {
       Type = ASE->getType();
       auto *Base = ASE->getBase()->IgnoreParenImpCasts();
@@ -7511,19 +7511,6 @@ OMPClause *Sema::ActOnOpenMPReductionClause(
                             diag::err_omp_reduction_incomplete_type))
       continue;
     // OpenMP [2.14.3.6, reduction clause, Restrictions]
-    // Arrays may not appear in a reduction clause.
-    if (Type.getNonReferenceType()->isArrayType()) {
-      Diag(ELoc, diag::err_omp_reduction_type_array) << Type << ERange;
-      if (!ASE && !OASE) {
-        bool IsDecl = VD->isThisDeclarationADefinition(Context) ==
-                      VarDecl::DeclarationOnly;
-        Diag(VD->getLocation(),
-             IsDecl ? diag::note_previous_decl : diag::note_defined_here)
-            << VD;
-      }
-      continue;
-    }
-    // OpenMP [2.14.3.6, reduction clause, Restrictions]
     // A list item that appears in a reduction clause must not be
     // const-qualified.
     if (Type.getNonReferenceType().isConstant(Context)) {
@@ -7636,8 +7623,9 @@ OMPClause *Sema::ActOnOpenMPReductionClause(
     auto *RHSVD = buildVarDecl(*this, ELoc, Type, VD->getName(),
                                VD->hasAttrs() ? &VD->getAttrs() : nullptr);
     auto PrivateTy = Type;
-    if (OASE) {
-      // For array sections only:
+    if (OASE ||
+        (DE && VD->getType().getNonReferenceType()->isVariablyModifiedType())) {
+      // For arays/array sections only:
       // Create pseudo array type for private copy. The size for this array will
       // be generated during codegen.
       // For array subscripts or single variables Private Ty is the same as Type
@@ -7646,7 +7634,9 @@ OMPClause *Sema::ActOnOpenMPReductionClause(
           Type, new (Context) OpaqueValueExpr(SourceLocation(),
                                               Context.getSizeType(), VK_RValue),
           ArrayType::Normal, /*IndexTypeQuals=*/0, SourceRange());
-    }
+    } else if (DE &&
+               Context.getAsArrayType(VD->getType().getNonReferenceType()))
+      PrivateTy = VD->getType().getNonReferenceType();
     // Private copy.
     auto *PrivateVD = buildVarDecl(*this, ELoc, PrivateTy, VD->getName(),
                                    VD->hasAttrs() ? &VD->getAttrs() : nullptr);