[OPENMP50]Codegen for nontemporal clause.

Summary:
Basic codegen for the declarations marked as nontemporal. Also, if the
base declaration in the member expression is marked as nontemporal,
lvalue for member decl access inherits nonteporal flag from the base
lvalue.

Reviewers: rjmccall, hfinkel, jdoerfert

Subscribers: guansong, arphaman, caomhin, kkwli0, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D71708

1 files changed, 41 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/CGOpenMPRuntime.cpp b/clang/lib/CodeGen/CGOpenMPRuntime.cpp
index 1aae18b4504..2a53e999353 100644
--- a/clang/lib/CodeGen/CGOpenMPRuntime.cpp
+++ b/clang/lib/CodeGen/CGOpenMPRuntime.cpp
@@ -17,6 +17,7 @@
 #include "CodeGenFunction.h"
 #include "clang/AST/Attr.h"
 #include "clang/AST/Decl.h"
+#include "clang/AST/OpenMPClause.h"
 #include "clang/AST/StmtOpenMP.h"
 #include "clang/Basic/BitmaskEnum.h"
 #include "clang/CodeGen/ConstantInitBuilder.h"
@@ -11341,6 +11342,46 @@ bool CGOpenMPRuntime::emitDeclareVariant(GlobalDecl GD, bool IsForDefinition) {
   return true;
 }
 
+CGOpenMPRuntime::NontemporalDeclsRAII::NontemporalDeclsRAII(
+    CodeGenModule &CGM, const OMPLoopDirective &S)
+    : CGM(CGM), NeedToPush(S.hasClausesOfKind<OMPNontemporalClause>()) {
+  assert(CGM.getLangOpts().OpenMP && "Not in OpenMP mode.");
+  if (!NeedToPush)
+    return;
+  NontemporalDeclsSet &DS =
+      CGM.getOpenMPRuntime().NontemporalDeclsStack.emplace_back();
+  for (const auto *C : S.getClausesOfKind<OMPNontemporalClause>()) {
+    for (const Stmt *Ref : C->private_refs()) {
+      const auto *SimpleRefExpr = cast<Expr>(Ref)->IgnoreParenImpCasts();
+      const ValueDecl *VD;
+      if (const auto *DRE = dyn_cast<DeclRefExpr>(SimpleRefExpr)) {
+        VD = DRE->getDecl();
+      } else {
+        const auto *ME = cast<MemberExpr>(SimpleRefExpr);
+        assert((ME->isImplicitCXXThis() ||
+                isa<CXXThisExpr>(ME->getBase()->IgnoreParenImpCasts())) &&
+               "Expected member of current class.");
+        VD = ME->getMemberDecl();
+      }
+      DS.insert(VD);
+    }
+  }
+}
+
+CGOpenMPRuntime::NontemporalDeclsRAII::~NontemporalDeclsRAII() {
+  if (!NeedToPush)
+    return;
+  CGM.getOpenMPRuntime().NontemporalDeclsStack.pop_back();
+}
+
+bool CGOpenMPRuntime::isNontemporalDecl(const ValueDecl *VD) const {
+  assert(CGM.getLangOpts().OpenMP && "Not in OpenMP mode.");
+
+  return llvm::any_of(
+      CGM.getOpenMPRuntime().NontemporalDeclsStack,
+      [VD](const NontemporalDeclsSet &Set) { return Set.count(VD) > 0; });
+}
+
 llvm::Function *CGOpenMPSIMDRuntime::emitParallelOutlinedFunction(
     const OMPExecutableDirective &D, const VarDecl *ThreadIDVar,
     OpenMPDirectiveKind InnermostKind, const RegionCodeGenTy &CodeGen) {