[OPENMP 4.5] Codegen for data members in 'linear' clause

OpenMP 4.5 allows privatization of non-static data members in OpenMP
constructs. Patch adds proper codegen support for data members in
'linear' clause

llvm-svn: 263003

2 files changed, 71 insertions, 29 deletions

diff --git a/clang/lib/CodeGen/CGStmtOpenMP.cpp b/clang/lib/CodeGen/CGStmtOpenMP.cpp
index 211155edd23..808af527a39 100644
--- a/clang/lib/CodeGen/CGStmtOpenMP.cpp
+++ b/clang/lib/CodeGen/CGStmtOpenMP.cpp
@@ -1114,17 +1114,19 @@ void CodeGenFunction::EmitOMPLinearClauseInit(const OMPLoopDirective &D) {
   for (const auto *C : D.getClausesOfKind<OMPLinearClause>()) {
     for (auto Init : C->inits()) {
       auto *VD = cast<VarDecl>(cast<DeclRefExpr>(Init)->getDecl());
-      auto *OrigVD = cast<VarDecl>(
-          cast<DeclRefExpr>(VD->getInit()->IgnoreImpCasts())->getDecl());
-      DeclRefExpr DRE(const_cast<VarDecl *>(OrigVD),
-                      CapturedStmtInfo->lookup(OrigVD) != nullptr,
-                      VD->getInit()->getType(), VK_LValue,
-                      VD->getInit()->getExprLoc());
-      AutoVarEmission Emission = EmitAutoVarAlloca(*VD);
-      EmitExprAsInit(&DRE, VD,
-               MakeAddrLValue(Emission.getAllocatedAddress(), VD->getType()),
-                     /*capturedByInit=*/false);
-      EmitAutoVarCleanups(Emission);
+      if (auto *Ref = dyn_cast<DeclRefExpr>(VD->getInit()->IgnoreImpCasts())) {
+        AutoVarEmission Emission = EmitAutoVarAlloca(*VD);
+        auto *OrigVD = cast<VarDecl>(Ref->getDecl());
+        DeclRefExpr DRE(const_cast<VarDecl *>(OrigVD),
+                        CapturedStmtInfo->lookup(OrigVD) != nullptr,
+                        VD->getInit()->getType(), VK_LValue,
+                        VD->getInit()->getExprLoc());
+        EmitExprAsInit(&DRE, VD, MakeAddrLValue(Emission.getAllocatedAddress(),
+                                                VD->getType()),
+                       /*capturedByInit=*/false);
+        EmitAutoVarCleanups(Emission);
+      } else
+        EmitVarDecl(*VD);
     }
     // Emit the linear steps for the linear clauses.
     // If a step is not constant, it is pre-calculated before the loop.
@@ -1137,14 +1139,26 @@ void CodeGenFunction::EmitOMPLinearClauseInit(const OMPLoopDirective &D) {
   }
 }
 
-static void emitLinearClauseFinal(CodeGenFunction &CGF,
-                                  const OMPLoopDirective &D) {
+static void emitLinearClauseFinal(
+    CodeGenFunction &CGF, const OMPLoopDirective &D,
+    const llvm::function_ref<llvm::Value *(CodeGenFunction &)> &CondGen) {
   if (!CGF.HaveInsertPoint())
     return;
+  llvm::BasicBlock *DoneBB = nullptr;
   // Emit the final values of the linear variables.
   for (const auto *C : D.getClausesOfKind<OMPLinearClause>()) {
     auto IC = C->varlist_begin();
     for (auto F : C->finals()) {
+      if (!DoneBB) {
+        if (auto *Cond = CondGen(CGF)) {
+          // If the first post-update expression is found, emit conditional
+          // block if it was requested.
+          auto *ThenBB = CGF.createBasicBlock(".omp.linear.pu");
+          DoneBB = CGF.createBasicBlock(".omp.linear.pu.done");
+          CGF.Builder.CreateCondBr(Cond, ThenBB, DoneBB);
+          CGF.EmitBlock(ThenBB);
+        }
+      }
       auto *OrigVD = cast<VarDecl>(cast<DeclRefExpr>(*IC)->getDecl());
       DeclRefExpr DRE(const_cast<VarDecl *>(OrigVD),
                       CGF.CapturedStmtInfo->lookup(OrigVD) != nullptr,
@@ -1158,8 +1172,10 @@ static void emitLinearClauseFinal(CodeGenFunction &CGF,
       ++IC;
     }
     if (auto *PostUpdate = C->getPostUpdateExpr())
-      EmitIgnoredExpr(PostUpdate);
+      CGF.EmitIgnoredExpr(PostUpdate);
   }
+  if (DoneBB)
+    CGF.EmitBlock(DoneBB, /*IsFinished=*/true);
 }
 
 static void emitAlignedClause(CodeGenFunction &CGF,
@@ -1296,13 +1312,26 @@ void CodeGenFunction::EmitOMPSimdInit(const OMPLoopDirective &D,
   emitSimdlenSafelenClause(*this, D, IsMonotonic);
 }
 
-void CodeGenFunction::EmitOMPSimdFinal(const OMPLoopDirective &D) {
+void CodeGenFunction::EmitOMPSimdFinal(
+    const OMPLoopDirective &D,
+    const llvm::function_ref<llvm::Value *(CodeGenFunction &)> &CondGen) {
   if (!HaveInsertPoint())
     return;
+  llvm::BasicBlock *DoneBB = nullptr;
   auto IC = D.counters().begin();
   for (auto F : D.finals()) {
     auto *OrigVD = cast<VarDecl>(cast<DeclRefExpr>((*IC))->getDecl());
     if (LocalDeclMap.count(OrigVD) || CapturedStmtInfo->lookup(OrigVD)) {
+      if (!DoneBB) {
+        if (auto *Cond = CondGen(*this)) {
+          // If the first post-update expression is found, emit conditional
+          // block if it was requested.
+          auto *ThenBB = createBasicBlock(".omp.final.then");
+          DoneBB = createBasicBlock(".omp.final.done");
+          Builder.CreateCondBr(Cond, ThenBB, DoneBB);
+          EmitBlock(ThenBB);
+        }
+      }
       DeclRefExpr DRE(const_cast<VarDecl *>(OrigVD),
                       CapturedStmtInfo->lookup(OrigVD) != nullptr,
                       (*IC)->getType(), VK_LValue, (*IC)->getExprLoc());
@@ -1315,7 +1344,8 @@ void CodeGenFunction::EmitOMPSimdFinal(const OMPLoopDirective &D) {
     }
     ++IC;
   }
-  emitLinearClauseFinal(*this, D);
+  if (DoneBB)
+    EmitBlock(DoneBB, /*IsFinished=*/true);
 }
 
 void CodeGenFunction::EmitOMPSimdDirective(const OMPSimdDirective &S) {
@@ -1387,7 +1417,10 @@ void CodeGenFunction::EmitOMPSimdDirective(const OMPSimdDirective &S) {
       emitPostUpdateForReductionClause(
           CGF, S, [](CodeGenFunction &) -> llvm::Value * { return nullptr; });
     }
-    CGF.EmitOMPSimdFinal(S);
+    CGF.EmitOMPSimdFinal(
+        S, [](CodeGenFunction &) -> llvm::Value * { return nullptr; });
+    emitLinearClauseFinal(
+        CGF, S, [](CodeGenFunction &) -> llvm::Value * { return nullptr; });
     // Emit: if (PreCond) - end.
     if (ContBlock) {
       CGF.EmitBranch(ContBlock);
@@ -1651,18 +1684,18 @@ bool CodeGenFunction::EmitOMPWorksharingLoop(const OMPLoopDirective &S) {
 
     emitAlignedClause(*this, S);
     EmitOMPLinearClauseInit(S);
+    // Emit helper vars inits.
+    LValue LB =
+        EmitOMPHelperVar(*this, cast<DeclRefExpr>(S.getLowerBoundVariable()));
+    LValue UB =
+        EmitOMPHelperVar(*this, cast<DeclRefExpr>(S.getUpperBoundVariable()));
+    LValue ST =
+        EmitOMPHelperVar(*this, cast<DeclRefExpr>(S.getStrideVariable()));
+    LValue IL =
+        EmitOMPHelperVar(*this, cast<DeclRefExpr>(S.getIsLastIterVariable()));
+
     // Emit 'then' code.
     {
-      // Emit helper vars inits.
-      LValue LB =
-          EmitOMPHelperVar(*this, cast<DeclRefExpr>(S.getLowerBoundVariable()));
-      LValue UB =
-          EmitOMPHelperVar(*this, cast<DeclRefExpr>(S.getUpperBoundVariable()));
-      LValue ST =
-          EmitOMPHelperVar(*this, cast<DeclRefExpr>(S.getStrideVariable()));
-      LValue IL =
-          EmitOMPHelperVar(*this, cast<DeclRefExpr>(S.getIsLastIterVariable()));
-
       OMPPrivateScope LoopScope(*this);
       if (EmitOMPFirstprivateClause(S, LoopScope)) {
         // Emit implicit barrier to synchronize threads and avoid data races on
@@ -1759,8 +1792,15 @@ bool CodeGenFunction::EmitOMPWorksharingLoop(const OMPLoopDirective &S) {
             S, Builder.CreateIsNotNull(EmitLoadOfScalar(IL, S.getLocStart())));
     }
     if (isOpenMPSimdDirective(S.getDirectiveKind())) {
-      EmitOMPSimdFinal(S);
+      EmitOMPSimdFinal(S, [&](CodeGenFunction &CGF) -> llvm::Value * {
+        return CGF.Builder.CreateIsNotNull(
+            CGF.EmitLoadOfScalar(IL, S.getLocStart()));
+      });
     }
+    emitLinearClauseFinal(*this, S, [&](CodeGenFunction &CGF) -> llvm::Value * {
+      return CGF.Builder.CreateIsNotNull(
+          CGF.EmitLoadOfScalar(IL, S.getLocStart()));
+    });
     // We're now done with the loop, so jump to the continuation block.
     if (ContBlock) {
       EmitBranch(ContBlock);
diff --git a/clang/lib/CodeGen/CodeGenFunction.h b/clang/lib/CodeGen/CodeGenFunction.h
index a84a0f0e73c..13a3acbaeda 100644
--- a/clang/lib/CodeGen/CodeGenFunction.h
+++ b/clang/lib/CodeGen/CodeGenFunction.h
@@ -2389,7 +2389,9 @@ private:
   /// Helpers for the OpenMP loop directives.
   void EmitOMPLoopBody(const OMPLoopDirective &D, JumpDest LoopExit);
   void EmitOMPSimdInit(const OMPLoopDirective &D, bool IsMonotonic = false);
-  void EmitOMPSimdFinal(const OMPLoopDirective &D);
+  void EmitOMPSimdFinal(
+      const OMPLoopDirective &D,
+      const llvm::function_ref<llvm::Value *(CodeGenFunction &)> &CondGen);
   /// \brief Emit code for the worksharing loop-based directive.
   /// \return true, if this construct has any lastprivate clause, false -
   /// otherwise.