[OPENMP50]Treat context selectors as expressions, not just strings.

[ABataev]

Summary

After some discussion, it was decided to allow not only identifiers as
context selectors, but also string literals.

[merge_guards_bot]

Build result: pass - 60439 tests passed, 0 failed and 726 were skipped.

Log files: console-log.txt, CMakeCache.txt

[jdoerfert]

Thx for this patch. Only two minor comments.

clang/include/clang/Basic/DiagnosticParseKinds.td

1230

I would have expected this error to be still accurate, maybe with the addition ", or quoted versions thereof".

clang/lib/Sema/SemaTemplateInstantiateDecl.cpp

424

When would ER not be usable here? Is there a valid use case or should we assert it is?

[ABataev]

clang/include/clang/Basic/DiagnosticParseKinds.td

1230

Currently, we could emit it only in codegen phase to avoid double converting from expression to string. Will emit it there.

clang/lib/Sema/SemaTemplateInstantiateDecl.cpp

424

If the instantiation is failed, the error message is emitted and ER is set to ExprError, which is not usable.

[ABataev]

Restored message + some small improvements.

[merge_guards_bot]

Build result: pass - 60475 tests passed, 0 failed and 726 were skipped.

Log files: console-log.txt, CMakeCache.txt

[ABataev]

Ping!

[jdoerfert]

clang/include/clang/Basic/DiagnosticParseKinds.td

1230

Why can't we emit this error if the user writes device={kind(gggggpu)} anymore? Even device={kind("gggggpu")} should be diagnosable early.

clang/lib/Sema/SemaTemplateInstantiateDecl.cpp

424

Thx.

[ABataev]

clang/include/clang/Basic/DiagnosticParseKinds.td

1230

The main problem here is the conversion and expression evaluation. We convert the data from the expression to strings at the codegen phase. I don't want to do the same thing for the second time in Sema just for diagnostic.

[jdoerfert]

clang/include/clang/Basic/DiagnosticParseKinds.td

1230

We have to convert it during sema already, actually during parsing. I'm working on declare variant begin/end support right now (part of TR8) which needs the information during parsing.

[ABataev]

clang/include/clang/Basic/DiagnosticParseKinds.td

1230

Hmmm, it is where we need to parse the code only if the context matches the trait? Ok, will rework to convert it in sema too. Seems to me, we'll need to match the context in both, codegen and sema. Will try to move the matcher somewhere to avoid duplication in sema and codege.

[jdoerfert]

clang/include/clang/Basic/DiagnosticParseKinds.td

1230

I put my patch up later tonight or tomorrow. It moves stuff around, we need to coordinate somehow.

[ABataev]

clang/include/clang/Basic/DiagnosticParseKinds.td

1230

I still won't work on it until Monday. So, if you have a good solution for the matcher, go ahead.

[ABataev]

Reworked attribute translationto try to reuse the context matching and scoring functionality with Sema.

[merge_guards_bot]

Build result: pass - 60659 tests passed, 0 failed and 726 were skipped.

Log files: console-log.txt, CMakeCache.txt

[ABataev]

Fixed misprint in the comment.

[merge_guards_bot]

Build result: pass - 60659 tests passed, 0 failed and 726 were skipped.

Log files: console-log.txt, CMakeCache.txt

[ABataev]

Rebase + moved function for best variant to FunctionDecl.

[merge_guards_bot]

Unit tests: pass. 60709 tests passed, 0 failed and 726 were skipped.

clang-format: fail. Please format your changes with clang-format by running git-clang-format HEAD^ or apply this patch.

Build artifacts: console-log.txt, CMakeCache.txt, clang-format.patch, test-results.xml, diff.json

[ABataev]

Fixed formatting

[merge_guards_bot]

Unit tests: pass. 60709 tests passed, 0 failed and 726 were skipped.

clang-format: fail. Please format your changes with clang-format by running git-clang-format HEAD^ or apply this patch.

Build artifacts: console-log.txt, CMakeCache.txt, clang-format.patch, test-results.xml, diff.json

[jdoerfert]

I haven't forgotten about this! With the other two changes to the declare variant going to happen now,as well, I figured we should look at this again from a high-level.

My plan now is:

1. Move all of the declare variant context stuff out of clang into the libFrontendOpenMP. This has various benefits, including reuse capabilities and the problem of where to put it (which was discussed briefly in my other declare variant patches), is gone.
2. Set it up to accept *constant* strings and non-string alike from the beginning. I'll also make it completely OMPKinds.def based with all the trait sets and selectors at least parsed properly. Rules what can be nested together, what can have a score, etc. are all reusable and mostly generated.
3. Introduce the declare variant begin/end stuff to get math support before the 10 fork.
4. Make all declare variant decisions in SemaOverload.

[jdoerfert]

In D70973#1793061, @jdoerfert wrote:

I haven't forgotten about this! With the other two changes to the declare variant going to happen now,as well, I figured we should look at this again from a high-level.

My plan now is:

1. Move all of the declare variant context stuff out of clang into the libFrontendOpenMP. This has various benefits, including reuse capabilities and the problem of where to put it (which was discussed briefly in my other declare variant patches), is gone.
2. Set it up to accept *constant* strings and non-string alike from the beginning. I'll also make it completely OMPKinds.def based with all the trait sets and selectors at least parsed properly. Rules what can be nested together, what can have a score, etc. are all reusable and mostly generated.
3. Introduce the declare variant begin/end stuff to get math support before the 10 fork.
4. Make all declare variant decisions in SemaOverload.

Part 1) and 2) are ready for review (D71830). I took some code from here to handle string literals the same as identifiers and I sprinkled a few '"' into the match clauses to test it.

(In contrast to this patch, with D71830 we will actually remove the quotes when we pretty print the AST instead of adding them.)

clang/include/clang/Basic/Attr.td

def OMPDeclareVariant : InheritableAttr {
   let HasCustomParsing = 1;
   let InheritEvenIfAlreadyPresent = 1;
   let Documentation = [OMPDeclareVariantDocs];
   let Args = [
     ExprArgument<"VariantFuncRef">,
     VariadicExprArgument<"Scores">,
     VariadicUnsignedArgument<"CtxSelectorSets">,
     VariadicUnsignedArgument<"CtxSelectors">,
-    VariadicStringArgument<"ImplVendors">,
-    VariadicStringArgument<"DeviceKinds">
+    VariadicExprArgument<"ImplVendors">,
+    VariadicExprArgument<"DeviceKinds">
   ];
   let AdditionalMembers = [{
     void printScore(raw_ostream & OS, const PrintingPolicy &Policy, unsigned I) const {
       if (const Expr *E = *std::next(scores_begin(), I)) {
         OS << "score(";
         E->printPretty(OS, nullptr, Policy);
         OS << "):";
       }
void printPrettyPragma(raw_ostream & OS, const PrintingPolicy &Policy)
               *std::next(ctxSelectors_begin(), K));
           switch (Ctx) {
           case OMP_CTX_vendor:
             assert(CtxSet == OMP_CTX_SET_implementation &&
                    "Expected implementation context selector set.");
             OS << "vendor(";
             printScore(OS, Policy, K);
             if (implVendors_size() > 0) {
-              OS << *implVendors(). begin();
-              for (StringRef VendorName : llvm::drop_begin(implVendors(), 1))
-                OS << ", " << VendorName;
+              (*implVendors().begin())->printPretty(OS, nullptr, Policy);
+              for (const Expr *VE : llvm::drop_begin(implVendors(), 1)) {
+                OS << ", ";
+                VE->printPretty(OS, nullptr, Policy);
+              }
             }
             OS << ")";
             break;
           case OMP_CTX_kind:
             assert(CtxSet == OMP_CTX_SET_device &&
                    "Expected device context selector set.");
             OS << "kind(";
             if (deviceKinds_size() > 0) {
-              OS << *deviceKinds().begin();
-              for (StringRef KindName : llvm::drop_begin(deviceKinds(), 1))
-                OS << ", " << KindName;
+              (*deviceKinds().begin())->printPretty(OS, nullptr, Policy);
+              for (const Expr *KE : llvm::drop_begin(deviceKinds(), 1)) {
+                OS << ", ";
+                KE->printPretty(OS, nullptr, Policy);
+              }
             }
             OS << ")";
             break;
           case OMP_CTX_unknown:
             llvm_unreachable("Unknown context selector.");
           }
         }
         OS << "}";

clang/include/clang/Basic/DiagnosticParseKinds.td

def err_omp_declare_variant_wrong_clause : Error<
   "expected '%0' clause on 'omp declare variant' directive">;
 def err_omp_declare_variant_no_ctx_selector : Error<
   "expected context selector in '%0' clause on 'omp declare variant' directive">;
 def err_omp_declare_variant_equal_expected : Error<
   "expected '=' after '%0' context selector set name on 'omp declare variant' directive">;
 def warn_omp_declare_variant_cs_name_expected : Warning<
   "unknown context selector in '%0' context selector set of 'omp declare variant' directive, ignored">,
   InGroup<OpenMPClauses>;
-def err_omp_declare_variant_item_expected : Error<
-  "expected %0 in '%1' context selector of '%2' selector set of 'omp declare variant' directive">;
 def err_omp_declare_variant_ctx_set_mutiple_use : Error<
   "context selector set '%0' is used already in the same 'omp declare variant' directive">;
 def note_omp_declare_variant_ctx_set_used_here : Note<
   "previously context selector set '%0' used here">;
 def err_omp_expected_comma_brace : Error<"expected '}' or ',' after '%0'">;
 def err_omp_declare_variant_ctx_mutiple_use : Error<
   "context trait selector '%0' is used already in the same '%1' context selector set of 'omp declare variant' directive">;
 def note_omp_declare_variant_ctx_used_here : Note<
   "previously context trait selector '%0' used here">;
 def warn_omp_more_one_device_type_clause : Warning<
   "more than one 'device_type' clause is specified">,
   InGroup<OpenMPClauses>;
-def err_omp_wrong_device_kind_trait : Error<
-  "unknown '%0' device kind trait in the 'device' context selector set, expected"
-  " one of 'host', 'nohost', 'cpu', 'gpu' or 'fpga'">;
+def note_omp_expected_context_selector_trait_string : Note<
+  "expected context trait string expression or identifier in '%0' context selector">;
 
 // Pragma loop support.
 def err_pragma_loop_missing_argument : Error<
   "missing argument; expected %select{an integer value|"
   "'enable'%select{|, 'full'}1%select{|, 'assume_safety'}2 or 'disable'}0">;
 def err_pragma_loop_invalid_option : Error<
   "%select{invalid|missing}0 option%select{ %1|}0; expected vectorize, "
   "vectorize_width, interleave, interleave_count, unroll, unroll_count, "

clang/include/clang/Basic/DiagnosticSemaKinds.td

def err_omp_declare_variant_incompat_types : Error<
   "variant in '#pragma omp declare variant' with type %0 is incompatible with type %1"
   >;
 def warn_omp_declare_variant_marked_as_declare_variant : Warning<
   "variant function in '#pragma omp declare variant' is itself marked as '#pragma omp declare variant'"
   >, InGroup<SourceUsesOpenMP>;
 def note_omp_marked_declare_variant_here : Note<"marked as 'declare variant' here">;
 def err_omp_one_defaultmap_each_category: Error<
   "at most one defaultmap clause for each variable-category can appear on the directive">;
+def err_omp_trait_not_string : Error<
+  "trait expression must have a string type, not %0">;
+def note_omp_trait_conversion_here : Note<
+  "conversion to a string type %0 declared here">;
+def err_omp_trait_ambiguous_conversion : Error<
+  "ambiguous conversion from type %0 to a string type">;
+def err_omp_trait_not_constant_string : Error<
+  "trait expression must be a constant string expression">;
 } // end of OpenMP category
 
 let CategoryName = "Related Result Type Issue" in {
 // Objective-C related result type compatibility
 def warn_related_result_type_compatibility_class : Warning<
   "method is expected to return an instance of its class type "
   "%diff{$, but is declared to return $|"
   ", but is declared to return different type}0,1">;

clang/include/clang/Sema/Sema.h

private:
   void markOpenMPDeclareVariantFuncsReferenced(SourceLocation Loc,
                                                FunctionDecl *Func,
                                                bool MightBeOdrUse);
 
 public:
   /// Struct to store the context selectors info for declare variant directive.
   using OMPCtxStringType = SmallString<8>;
   using OMPCtxSelectorData =
-      OpenMPCtxSelectorData<SmallVector<OMPCtxStringType, 4>, ExprResult>;
+      OpenMPCtxSelectorData<SmallVector<ExprResult, 4>, ExprResult>;
 
   /// Checks if the variant/multiversion functions are compatible.
   bool areMultiversionVariantFunctionsCompatible(
       const FunctionDecl *OldFD, const FunctionDecl *NewFD,
       const PartialDiagnostic &NoProtoDiagID,
       const PartialDiagnosticAt &NoteCausedDiagIDAt,
       const PartialDiagnosticAt &NoSupportDiagIDAt,
       const PartialDiagnosticAt &DiffDiagIDAt, bool TemplatesSupported,
       bool ConstexprSupported, bool CLinkageMayDiffer);
 
+  /// Builds StringLiteral out of the specified trait name.
+  ExprResult ActOnOpenMPTraitId(SourceLocation Loc, StringRef TraitName);
+
   /// Function tries to capture lambda's captured variables in the OpenMP region
   /// before the original lambda is captured.
   void tryCaptureOpenMPLambdas(ValueDecl *V);
 
   /// Return true if the provided declaration \a VD should be captured by
   /// reference.
   /// \param Level Relative level of nested OpenMP construct for that the check
   /// is performed.

clang/lib/CodeGen/CGOpenMPRuntime.cpp

 #include "CGRecordLayout.h"
 #include "CodeGenFunction.h"
 #include "clang/CodeGen/ConstantInitBuilder.h"
 #include "clang/AST/Decl.h"
 #include "clang/AST/StmtOpenMP.h"
 #include "clang/Basic/BitmaskEnum.h"
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/SetOperations.h"
+#include "llvm/ADT/UniqueVector.h"
 #include "llvm/Bitcode/BitcodeReader.h"
 #include "llvm/IR/DerivedTypes.h"
 #include "llvm/IR/GlobalValue.h"
 #include "llvm/IR/Value.h"
+#include "llvm/Support/ConvertUTF.h"
 #include "llvm/Support/Format.h"
 #include "llvm/Support/raw_ostream.h"
 #include <cassert>
 
 using namespace clang;
 using namespace CodeGen;
 
 namespace {
Addr = CGF.Builder.CreatePointerBitCastOrAddrSpaceCast(
       Addr,
       CGF.ConvertTypeForMem(CGM.getContext().getPointerType(CVD->getType())),
       CVD->getName() + ".addr");
   return Address(Addr, Align);
 }
 
 namespace {
 using OMPContextSelectorData =
-    OpenMPCtxSelectorData<ArrayRef<StringRef>, llvm::APSInt>;
+    OpenMPCtxSelectorData<SmallVector<SmallString<8>, 4>, llvm::APSInt>;
 using CompleteOMPContextSelectorData = SmallVector<OMPContextSelectorData, 4>;
 } // anonymous namespace
 
 /// Checks current context and returns true if it matches the context selector.
 template <OpenMPContextSelectorSetKind CtxSet, OpenMPContextSelectorKind Ctx,
           typename... Arguments>
 static bool checkContext(const OMPContextSelectorData &Data,
                          Arguments... Params) {
case OMP_CTX_kind:
       break;
     case OMP_CTX_unknown:
       llvm_unreachable("Unknown context selector kind.");
     }
   }
   return true;
 }
 
+template <typename T>
+static void
+convertTraitsToUniqueStringsVector(T &&Range,
+                                   llvm::UniqueVector<std::string> &Values) {
+  for (const Expr *Trait : Range) {
+    const auto *SL = cast<StringLiteral>(Trait);
+    std::string Name;
+    switch (SL->getKind()) {
+    case StringLiteral::Ascii:
+    case StringLiteral::UTF8:
+      Name = SL->getString();
+      break;
+    case StringLiteral::UTF16:
+      if (!llvm::convertUTF16ToUTF8String(
+              llvm::makeArrayRef(SL->getBytes().begin(), SL->getBytes().end()),
+              Name)) {
+        Values.reset();
+        return;
+      }
+      break;
+    case StringLiteral::UTF32:
+      llvm_unreachable("UTF32 is unsupported.");
+    case StringLiteral::Wide: {
+      std::wstring WideString;
+      for (int I = 0, E = SL->getLength(); I < E; ++I)
+        WideString += static_cast<wchar_t>(SL->getCodeUnit(I));
+      if (!llvm::convertWideToUTF8(WideString, Name)) {
+        Values.reset();
+        return;
+      }
+      break;
+    }
+    }
+    Values.insert(Name);
+  }
+}
+
 static CompleteOMPContextSelectorData
 translateAttrToContextSelectorData(ASTContext &C,
                                    const OMPDeclareVariantAttr *A) {
   CompleteOMPContextSelectorData Data;
   for (unsigned I = 0, E = A->scores_size(); I < E; ++I) {
-    Data.emplace_back();
     auto CtxSet = static_cast<OpenMPContextSelectorSetKind>(
         *std::next(A->ctxSelectorSets_begin(), I));
     auto Ctx = static_cast<OpenMPContextSelectorKind>(
         *std::next(A->ctxSelectors_begin(), I));
-    Data.back().CtxSet = CtxSet;
-    Data.back().Ctx = Ctx;
     const Expr *Score = *std::next(A->scores_begin(), I);
-    Data.back().Score = Score->EvaluateKnownConstInt(C);
+    llvm::UniqueVector<std::string> Values;
     switch (Ctx) {
     case OMP_CTX_vendor:
       assert(CtxSet == OMP_CTX_SET_implementation &&
              "Expected implementation context selector set.");
-      Data.back().Names =
-          llvm::makeArrayRef(A->implVendors_begin(), A->implVendors_end());
+      convertTraitsToUniqueStringsVector(A->implVendors(), Values);
       break;
     case OMP_CTX_kind:
       assert(CtxSet == OMP_CTX_SET_device &&
              "Expected device context selector set.");
-      Data.back().Names =
-          llvm::makeArrayRef(A->deviceKinds_begin(), A->deviceKinds_end());
+      convertTraitsToUniqueStringsVector(A->deviceKinds(), Values);
       break;
     case OMP_CTX_unknown:
       llvm_unreachable("Unknown context selector kind.");
     }
+    Data.emplace_back(CtxSet, Ctx, Score->EvaluateKnownConstInt(C), Values);
   }
   return Data;
 }
 
 static bool isStrictSubset(const CompleteOMPContextSelectorData &LHS,
                            const CompleteOMPContextSelectorData &RHS) {
   llvm::SmallDenseMap<std::pair<int, int>, llvm::StringSet<>, 4> RHSData;
   for (const OMPContextSelectorData &D : RHS) {

clang/lib/Parse/ParseOpenMP.cpp

static ExprResult parseContextScore(Parser &P) {
   if (P.getCurToken().is(tok::colon))
     (void)P.ConsumeAnyToken();
   else
     P.Diag(P.getCurToken(), diag::warn_pragma_expected_colon)
         << "context selector score clause";
   return ScoreExpr;
 }
 
+/// Tries to parse trait constraint as an identifier or constant string literal
+/// expression.
+/// '(' [ 'score' '(' <score _expr> ')' ':' ] <trait> { ',' <trait> } ')'
+static void
+parseTraitStringExpression(Parser &P, OpenMPContextSelectorSetKind CSSKind,
+                           OpenMPContextSelectorKind CSKind, bool WithScore,
+                           StringRef FullDescriptionForPuncMsg,
+                           SmallVectorImpl<Sema::OMPCtxSelectorData> &Data) {
+  // Parse '('.
+  BalancedDelimiterTracker T(P, tok::l_paren, tok::annot_pragma_openmp_end);
+  (void)T.expectAndConsume(diag::err_expected_lparen_after,
+                           getOpenMPContextSelectorName(CSKind).data());
+  ExprResult Score;
+  if (WithScore)
+    Score = parseContextScore(P);
+  SmallVector<ExprResult, 4> Traits;
+  const Token &Tok = P.getCurToken();
+  SourceLocation PrevLoc;
+  do {
+    PrevLoc = Tok.getLocation();
+    // Parse trait value, which is constant expression of string type or
+    // identifier.
+    ExprResult Trait;
+    if (Tok.isAnyIdentifier()) {
+      Sema::OMPCtxStringType Buffer;
+      StringRef TraitName = P.getPreprocessor().getSpelling(Tok, Buffer);
+      (void)P.ConsumeToken();
+      Trait = P.getActions().ActOnOpenMPTraitId(PrevLoc, TraitName);
+    } else {
+      Trait = P.ParseConstantExpression();
+    }
+    if (!Trait.isUsable())
+      P.Diag(PrevLoc, diag::note_omp_expected_context_selector_trait_string)
+          << getOpenMPContextSelectorName(CSKind);
+    else
+      Traits.push_back(Trait);
+    if (!P.TryConsumeToken(tok::comma) && Tok.isNot(tok::r_paren))
+      P.Diag(Tok, diag::err_expected_punc) << FullDescriptionForPuncMsg;
+  } while (Tok.isNot(tok::r_paren) && Tok.isNot(tok::annot_pragma_openmp_end) &&
+           PrevLoc.getRawEncoding() != Tok.getLocation().getRawEncoding());
+  // Parse ')'.
+  (void)T.consumeClose();
+  if (!Traits.empty())
+    Data.emplace_back(CSSKind, CSKind, Score, Traits);
+}
+
 /// Parse context selector for 'implementation' selector set:
 /// 'vendor' '(' [ 'score' '(' <score _expr> ')' ':' ] <vendor> { ',' <vendor> }
 /// ')'
 static void
 parseImplementationSelector(Parser &P, SourceLocation Loc,
                             llvm::StringMap<SourceLocation> &UsedCtx,
                             SmallVectorImpl<Sema::OMPCtxSelectorData> &Data) {
   const Token &Tok = P.getCurToken();
if (!Res.second) {
     P.Diag(Tok.getLocation(), diag::err_omp_declare_variant_ctx_mutiple_use)
         << CtxSelectorName << "implementation";
     P.Diag(Res.first->getValue(), diag::note_omp_declare_variant_ctx_used_here)
         << CtxSelectorName;
   }
   OpenMPContextSelectorKind CSKind = getOpenMPContextSelector(CtxSelectorName);
   (void)P.ConsumeToken();
   switch (CSKind) {
-  case OMP_CTX_vendor: {
-    // Parse '('.
-    BalancedDelimiterTracker T(P, tok::l_paren, tok::annot_pragma_openmp_end);
-    (void)T.expectAndConsume(diag::err_expected_lparen_after,
-                             CtxSelectorName.data());
-    ExprResult Score = parseContextScore(P);
-    llvm::UniqueVector<Sema::OMPCtxStringType> Vendors;
-    do {
-      // Parse <vendor>.
-      StringRef VendorName;
-      if (Tok.is(tok::identifier)) {
-        Buffer.clear();
-        VendorName = P.getPreprocessor().getSpelling(P.getCurToken(), Buffer);
-        (void)P.ConsumeToken();
-        if (!VendorName.empty())
-          Vendors.insert(VendorName);
-      } else {
-        P.Diag(Tok.getLocation(), diag::err_omp_declare_variant_item_expected)
-            << "vendor identifier"
-            << "vendor"
-            << "implementation";
-      }
-      if (!P.TryConsumeToken(tok::comma) && Tok.isNot(tok::r_paren)) {
-        P.Diag(Tok, diag::err_expected_punc)
-            << (VendorName.empty() ? "vendor name" : VendorName);
-      }
-    } while (Tok.is(tok::identifier));
-    // Parse ')'.
-    (void)T.consumeClose();
-    if (!Vendors.empty())
-      Data.emplace_back(OMP_CTX_SET_implementation, CSKind, Score, Vendors);
+  case OMP_CTX_vendor:
+    parseTraitStringExpression(P, OMP_CTX_SET_implementation, CSKind,
+                               /*WithScore=*/true, "vendor name", Data);
     break;
-  }
   case OMP_CTX_kind:
   case OMP_CTX_unknown:
     P.Diag(Tok.getLocation(), diag::warn_omp_declare_variant_cs_name_expected)
         << "implementation";
     // Skip until either '}', ')', or end of directive.
     while (!P.SkipUntil(tok::r_brace, tok::r_paren,
                         tok::annot_pragma_openmp_end, Parser::StopBeforeMatch))
       ;
if (!Res.second) {
     P.Diag(Tok.getLocation(), diag::err_omp_declare_variant_ctx_mutiple_use)
         << CtxSelectorName << "device";
     P.Diag(Res.first->getValue(), diag::note_omp_declare_variant_ctx_used_here)
         << CtxSelectorName;
   }
   OpenMPContextSelectorKind CSKind = getOpenMPContextSelector(CtxSelectorName);
   (void)P.ConsumeToken();
   switch (CSKind) {
-  case OMP_CTX_kind: {
-    // Parse '('.
-    BalancedDelimiterTracker T(P, tok::l_paren, tok::annot_pragma_openmp_end);
-    (void)T.expectAndConsume(diag::err_expected_lparen_after,
-                             CtxSelectorName.data());
-    llvm::UniqueVector<Sema::OMPCtxStringType> Kinds;
-    do {
-      // Parse <kind>.
-      StringRef KindName;
-      if (Tok.is(tok::identifier)) {
-        Buffer.clear();
-        KindName = P.getPreprocessor().getSpelling(P.getCurToken(), Buffer);
-        SourceLocation SLoc = P.getCurToken().getLocation();
-        (void)P.ConsumeToken();
-        if (llvm::StringSwitch<bool>(KindName)
-                .Case("host", false)
-                .Case("nohost", false)
-                .Case("cpu", false)
-                .Case("gpu", false)
-                .Case("fpga", false)
-                .Default(true)) {
-          P.Diag(SLoc, diag::err_omp_wrong_device_kind_trait) << KindName;
-        } else {
-          Kinds.insert(KindName);
-        }
-      } else {
-        P.Diag(Tok.getLocation(), diag::err_omp_declare_variant_item_expected)
-            << "'host', 'nohost', 'cpu', 'gpu', or 'fpga'"
-            << "kind"
-            << "device";
-      }
-      if (!P.TryConsumeToken(tok::comma) && Tok.isNot(tok::r_paren)) {
-        P.Diag(Tok, diag::err_expected_punc)
-            << (KindName.empty() ? "kind of device" : KindName);
-      }
-    } while (Tok.is(tok::identifier));
-    // Parse ')'.
-    (void)T.consumeClose();
-    if (!Kinds.empty())
-      Data.emplace_back(OMP_CTX_SET_device, CSKind, ExprResult(), Kinds);
+  case OMP_CTX_kind:
+    parseTraitStringExpression(P, OMP_CTX_SET_device, CSKind,
+                               /*WithScore=*/false, "kind of device", Data);
     break;
-  }
   case OMP_CTX_vendor:
   case OMP_CTX_unknown:
     P.Diag(Tok.getLocation(), diag::warn_omp_declare_variant_cs_name_expected)
         << "device";
     // Skip until either '}', ')', or end of directive.
     while (!P.SkipUntil(tok::r_brace, tok::r_paren,
                         tok::annot_pragma_openmp_end, Parser::StopBeforeMatch))
       ;

clang/lib/Sema/SemaOpenMP.cpp

if (areMultiversionVariantFunctionsCompatible(
                               PDiag(diag::err_omp_declare_variant_diff)
                                   << FD->getLocation()),
           /*TemplatesSupported=*/true, /*ConstexprSupported=*/false,
           /*CLinkageMayDiffer=*/true))
     return None;
   return std::make_pair(FD, cast<Expr>(DRE));
 }
 
+static ExprResult performImplicitStringConversion(Sema &S, Expr *E) {
+  if (E->isTypeDependent() || E->isValueDependent() ||
+      E->isInstantiationDependent())
+    return E;
+  E = S.DefaultFunctionArrayLvalueConversion(E).get();
+  if (!E)
+    return ExprError();
+  class StringConverter : public Sema::ContextualImplicitConverter {
+  public:
+    StringConverter()
+        : Sema::ContextualImplicitConverter(/*Suppress=*/false,
+                                            /*SuppressConversion=*/true) {}
+
+    bool match(QualType ConvType) override {
+      if (ConvType->isArrayType() || ConvType->isPointerType()) {
+        const Type *ElTy = ConvType->getPointeeOrArrayElementType();
+        return ElTy->isWideCharType() || ElTy->isCharType() ||
+               ElTy->isChar8Type() || ElTy->isChar16Type();
+      }
+      return false;
+    }
+
+    Sema::SemaDiagnosticBuilder diagnoseNoMatch(Sema &S, SourceLocation Loc,
+                                                QualType T) override {
+      return S.Diag(Loc, diag::err_omp_trait_not_string) << T;
+    }
+
+    Sema::SemaDiagnosticBuilder diagnoseIncomplete(Sema &S, SourceLocation Loc,
+                                                   QualType T) override {
+      return S.Diag(Loc, diag::err_omp_incomplete_type) << T;
+    }
+
+    Sema::SemaDiagnosticBuilder diagnoseExplicitConv(Sema &S,
+                                                     SourceLocation Loc,
+                                                     QualType T,
+                                                     QualType ConvTy) override {
+      return S.Diag(Loc, diag::err_omp_explicit_conversion) << T << ConvTy;
+    }
+
+    Sema::SemaDiagnosticBuilder noteExplicitConv(Sema &S,
+                                                 CXXConversionDecl *Conv,
+                                                 QualType ConvTy) override {
+      return S.Diag(Conv->getLocation(), diag::note_omp_trait_conversion_here)
+             << ConvTy;
+    }
+
+    Sema::SemaDiagnosticBuilder diagnoseAmbiguous(Sema &S, SourceLocation Loc,
+                                                  QualType T) override {
+      return S.Diag(Loc, diag::err_omp_trait_ambiguous_conversion) << T;
+    }
+
+    Sema::SemaDiagnosticBuilder noteAmbiguous(Sema &S, CXXConversionDecl *Conv,
+                                              QualType ConvTy) override {
+      return S.Diag(Conv->getLocation(), diag::note_omp_trait_conversion_here)
+             << ConvTy;
+    }
+
+    Sema::SemaDiagnosticBuilder diagnoseConversion(Sema &S, SourceLocation Loc,
+                                                   QualType T,
+                                                   QualType ConvTy) override {
+      llvm_unreachable("conversion functions are permitted");
+    }
+  } Converter;
+
+  ExprResult ER =
+      S.PerformContextualImplicitConversion(E->getBeginLoc(), E, Converter);
+  if (!ER.isUsable())
+    return ExprError();
+  E = ER.get();
+  Expr::EvalResult Res;
+  if (!E->EvaluateAsRValue(Res, S.Context) || !Res.Val.isLValue()) {
+    S.Diag(E->getExprLoc(), diag::err_omp_trait_not_constant_string)
+        << E->getSourceRange();
+    return ExprError();
+  }
+  const auto *SL = dyn_cast_or_null<StringLiteral>(
+      Res.Val.getLValueBase().dyn_cast<const Expr *>());
+  if (!SL) {
+    S.Diag(E->getExprLoc(), diag::err_omp_trait_not_constant_string)
+        << E->getSourceRange();
+    return ExprError();
+  }
+  return StringLiteral::Create(S.Context, SL->getBytes(), SL->getKind(),
+                               SL->isPascal(), SL->getType(), E->getExprLoc());
+}
+
 void Sema::ActOnOpenMPDeclareVariantDirective(
     FunctionDecl *FD, Expr *VariantRef, SourceRange SR,
     ArrayRef<OMPCtxSelectorData> Data) {
   if (Data.empty())
     return;
   SmallVector<Expr *, 4> CtxScores;
   SmallVector<unsigned, 4> CtxSets;
   SmallVector<unsigned, 4> Ctxs;
-  SmallVector<StringRef, 4> ImplVendors, DeviceKinds;
+  SmallVector<Expr *, 4> ImplVendors, DeviceKinds;
   bool IsError = false;
   for (const OMPCtxSelectorData &D : Data) {
     OpenMPContextSelectorSetKind CtxSet = D.CtxSet;
     OpenMPContextSelectorKind Ctx = D.Ctx;
     if (CtxSet == OMP_CTX_SET_unknown || Ctx == OMP_CTX_unknown)
       return;
     Expr *Score = nullptr;
     if (D.Score.isUsable()) {
if (D.Score.isUsable()) {
       // implemented.
       int L = 0; // Currently set the number of traits in construct set to 0,
                  // since the construct trait set in not supported yet.
       if (CtxSet == OMP_CTX_SET_device && Ctx == OMP_CTX_kind)
         Score = ActOnIntegerConstant(SourceLocation(), std::pow(2, L)).get();
       else
         Score = ActOnIntegerConstant(SourceLocation(), 0).get();
     }
+    for (ExprResult ER : D.Names) {
+      ER = performImplicitStringConversion(*this, ER.get());
+      if (!ER.isUsable()) {
+        IsError = true;
+        continue;
+      }
       switch (Ctx) {
       case OMP_CTX_vendor:
         assert(CtxSet == OMP_CTX_SET_implementation &&
                "Expected implementation context selector set.");
-      ImplVendors.append(D.Names.begin(), D.Names.end());
+        ImplVendors.push_back(ER.get());
         break;
       case OMP_CTX_kind:
         assert(CtxSet == OMP_CTX_SET_device &&
                "Expected device context selector set.");
-      DeviceKinds.append(D.Names.begin(), D.Names.end());
+        DeviceKinds.push_back(ER.get());
         break;
       case OMP_CTX_unknown:
         llvm_unreachable("Unknown context selector kind.");
       }
+    }
     IsError = IsError || !Score;
     CtxSets.push_back(CtxSet);
     Ctxs.push_back(Ctx);
     CtxScores.push_back(Score);
   }
   if (!IsError) {
     auto *NewAttr = OMPDeclareVariantAttr::CreateImplicit(
         Context, VariantRef, CtxScores.begin(), CtxScores.size(),
         CtxSets.begin(), CtxSets.size(), Ctxs.begin(), Ctxs.size(),
         ImplVendors.begin(), ImplVendors.size(), DeviceKinds.begin(),
         DeviceKinds.size(), SR);
     FD->addAttr(NewAttr);
   }
 }
 
+ExprResult Sema::ActOnOpenMPTraitId(SourceLocation Loc, StringRef TraitName) {
+  return StringLiteral::Create(
+      Context, TraitName, StringLiteral::Ascii, /*Pascal=*/false,
+      Context.getStringLiteralArrayType(Context.CharTy, TraitName.size()), Loc);
+}
+
 void Sema::markOpenMPDeclareVariantFuncsReferenced(SourceLocation Loc,
                                                    FunctionDecl *Func,
                                                    bool MightBeOdrUse) {
   assert(LangOpts.OpenMP && "Expected OpenMP mode.");
 
   if (!Func->isDependentContext() && Func->hasAttrs()) {
     for (OMPDeclareVariantAttr *A :
          Func->specific_attrs<OMPDeclareVariantAttr>()) {

clang/lib/Sema/SemaTemplateInstantiateDecl.cpp

for (unsigned I = 0, E = Attr.scores_size(); I < E; ++I) {
     ExprResult Score;
     if (Expr *E = *std::next(Attr.scores_begin(), I))
       Score = Subst(E);
     // Instantiate the attribute.
     auto CtxSet = static_cast<OpenMPContextSelectorSetKind>(
         *std::next(Attr.ctxSelectorSets_begin(), I));
     auto Ctx = static_cast<OpenMPContextSelectorKind>(
         *std::next(Attr.ctxSelectors_begin(), I));
-    switch (CtxSet) {
-    case OMP_CTX_SET_implementation:
-      switch (Ctx) {
-      case OMP_CTX_vendor:
-        Data.emplace_back(CtxSet, Ctx, Score, Attr.implVendors());
-        break;
-      case OMP_CTX_kind:
-      case OMP_CTX_unknown:
-        llvm_unreachable("Unexpected context selector kind.");
+    SmallVector<ExprResult, 4> Values;
+      assert(CtxSet == OMP_CTX_SET_implementation &&
+             "Expected implementation context selector set.");
+      for (Expr *Val : Attr.implVendors()) {
+        ExprResult ER = Subst(Val);
+        if (ER.isUsable())
+          Values.push_back(ER);
       }
       break;
-    case OMP_CTX_SET_device:
-      switch (Ctx) {
-      case OMP_CTX_kind:
-        Data.emplace_back(CtxSet, Ctx, Score, Attr.deviceKinds());
-        break;
-      case OMP_CTX_vendor:
-      case OMP_CTX_unknown:
-        llvm_unreachable("Unexpected context selector kind.");
-      }
-      break;
-    case OMP_CTX_SET_unknown:
-      llvm_unreachable("Unexpected context selector set kind.");
-    }
+      assert(CtxSet == OMP_CTX_SET_device &&
+             "Expected device context selector set.");
+      for (Expr *Val : Attr.deviceKinds()) {
+        ExprResult ER = Subst(Val);
+        if (ER.isUsable())
+          Values.push_back(ER);
+      }
+    Data.emplace_back(CtxSet, Ctx, Score, Values);
   }
   S.ActOnOpenMPDeclareVariantDirective(DeclVarData.getValue().first,
                                        DeclVarData.getValue().second,
                                        Attr.getRange(), Data);
 }
 
 static void instantiateDependentAMDGPUFlatWorkGroupSizeAttr(
     Sema &S, const MultiLevelTemplateArgumentList &TemplateArgs,

clang/test/OpenMP/declare_variant_ast_print.c

 // RUN: %clang_cc1 -verify -fopenmp -x c -std=c99 -ast-print %s -o - -Wno-openmp-clauses | FileCheck %s
 
 // RUN: %clang_cc1 -verify -fopenmp-simd -x c -std=c99 -ast-print %s -o - -Wno-openmp-clauses | FileCheck %s
 
 // expected-no-diagnostics
 
 int foo(void);
 
 #pragma omp declare variant(foo) match(xxx={}, yyy={ccc})
 #pragma omp declare variant(foo) match(xxx={vvv})
 #pragma omp declare variant(foo) match(implementation={vendor(llvm)}, device={kind(fpga)})
 #pragma omp declare variant(foo) match(implementation={vendor(llvm), xxx})
-#pragma omp declare variant(foo) match(implementation={vendor(unknown)}, device={kind(gpu)})
-#pragma omp declare variant(foo) match(implementation={vendor(score(5): ibm, xxx, ibm)}, device={kind(cpu, nohost)})
+#pragma omp declare variant(foo) match(implementation={vendor(unknown)}, device={kind("gpu")})
+#pragma omp declare variant(foo) match(implementation={vendor(score(5): ibm, "xxx", ibm)}, device={kind(cpu, nohost)})
 #pragma omp declare variant(foo) match(device={kind(host)})
-#pragma omp declare variant(foo) match(device={kind(nohost), xxx})
+#pragma omp declare variant(foo) match(device={kind("nohost"), xxx})
 int bar(void);
 
 // CHECK:      int foo();
-// CHECK-NEXT: #pragma omp declare variant(foo) match(device={kind(nohost)})
-// CHECK-NEXT: #pragma omp declare variant(foo) match(device={kind(host)})
-// CHECK-NEXT: #pragma omp declare variant(foo) match(implementation={vendor(score(5):ibm, xxx)},device={kind(cpu, nohost)})
-// CHECK-NEXT: #pragma omp declare variant(foo) match(implementation={vendor(score(0):unknown)},device={kind(gpu)})
-// CHECK-NEXT: #pragma omp declare variant(foo) match(implementation={vendor(score(0):llvm)})
-// CHECK-NEXT: #pragma omp declare variant(foo) match(implementation={vendor(score(0):llvm)},device={kind(fpga)})
+// CHECK-NEXT: #pragma omp declare variant(foo) match(device={kind("nohost")})
+// CHECK-NEXT: #pragma omp declare variant(foo) match(device={kind("host")})
+// CHECK-NEXT: #pragma omp declare variant(foo) match(implementation={vendor(score(5):"ibm", "xxx", "ibm")},device={kind("cpu", "nohost")})
+// CHECK-NEXT: #pragma omp declare variant(foo) match(implementation={vendor(score(0):"unknown")},device={kind("gpu")})
+// CHECK-NEXT: #pragma omp declare variant(foo) match(implementation={vendor(score(0):"llvm")})
+// CHECK-NEXT: #pragma omp declare variant(foo) match(implementation={vendor(score(0):"llvm")},device={kind("fpga")})
 // CHECK-NEXT: int bar();

clang/test/OpenMP/declare_variant_ast_print.cpp

 // CHECK-NEXT: }
 template <typename T>
 T foofoo() { return T(); }
 
 // CHECK:      template<> int foofoo<int>() {
 // CHECK-NEXT: return int();
 // CHECK-NEXT: }
 
-// CHECK:      #pragma omp declare variant(foofoo<int>) match(implementation={vendor(score(5):ibm)},device={kind(fpga)})
-// CHECK-NEXT: #pragma omp declare variant(foofoo<int>) match(implementation={vendor(score(0):unknown)})
-// CHECK-NEXT: #pragma omp declare variant(foofoo<int>) match(implementation={vendor(score(0):llvm)},device={kind(cpu)})
+// CHECK:      #pragma omp declare variant(foofoo<int>) match(implementation={vendor(score(5):"ibm")},device={kind("fpga")})
+// CHECK-NEXT: #pragma omp declare variant(foofoo<int>) match(implementation={vendor(score(0):"unknown")})
+// CHECK-NEXT: #pragma omp declare variant(foofoo<int>) match(implementation={vendor(score(0):"llvm")},device={kind("cpu")})
 // CHECK-NEXT: int bar();
 #pragma omp declare variant(foofoo <int>) match(xxx = {})
 #pragma omp declare variant(foofoo <int>) match(xxx = {vvv})
 #pragma omp declare variant(foofoo <int>) match(implementation={vendor(llvm), xxx}, device={kind(cpu)})
 #pragma omp declare variant(foofoo <int>) match(implementation={vendor(unknown)})
 #pragma omp declare variant(foofoo <int>) match(implementation={vendor(score(5): ibm)}, device={kind(fpga)})
 int bar();
 
-// CHECK:      #pragma omp declare variant(foofoo<T>) match(implementation={vendor(score(C + 5):ibm, xxx)},device={kind(cpu, host)})
-// CHECK-NEXT: #pragma omp declare variant(foofoo<T>) match(implementation={vendor(score(0):unknown)})
-// CHECK-NEXT: #pragma omp declare variant(foofoo<T>) match(implementation={vendor(score(0):llvm)},device={kind(cpu)})
+// CHECK:      #pragma omp declare variant(foofoo<T>) match(implementation={vendor(score(C + 5):"ibm", "xxx", "ibm")},device={kind("cpu", "host")})
+// CHECK-NEXT: #pragma omp declare variant(foofoo<T>) match(implementation={vendor(score(0):"unknown")})
+// CHECK-NEXT: #pragma omp declare variant(foofoo<T>) match(implementation={vendor(score(0):"llvm")},device={kind("cpu")})
 // CHECK-NEXT: template <typename T, int C> T barbar();
 #pragma omp declare variant(foofoo <T>) match(xxx = {})
 #pragma omp declare variant(foofoo <T>) match(xxx = {vvv})
 #pragma omp declare variant(foofoo <T>) match(user = {score(<expr>) : condition(<expr>)})
 #pragma omp declare variant(foofoo <T>) match(user = {score(<expr>) : condition(<expr>)})
 #pragma omp declare variant(foofoo <T>) match(user = {condition(<expr>)})
 #pragma omp declare variant(foofoo <T>) match(user = {condition(<expr>)})
 #pragma omp declare variant(foofoo <T>) match(implementation={vendor(llvm)},device={kind(cpu)})
 #pragma omp declare variant(foofoo <T>) match(implementation={vendor(unknown)})
 #pragma omp declare variant(foofoo <T>) match(implementation={vendor(score(C+5): ibm, xxx, ibm)},device={kind(cpu,host)})
 template <typename T, int C>
 T barbar();
 
-// CHECK:      #pragma omp declare variant(foofoo<int>) match(implementation={vendor(score(3 + 5):ibm, xxx)},device={kind(cpu, host)})
-// CHECK-NEXT: #pragma omp declare variant(foofoo<int>) match(implementation={vendor(score(0):unknown)})
-// CHECK-NEXT: #pragma omp declare variant(foofoo<int>) match(implementation={vendor(score(0):llvm)},device={kind(cpu)})
+// CHECK:      #pragma omp declare variant(foofoo<int>) match(implementation={vendor(score(3 + 5):"ibm", "xxx", "ibm")},device={kind("cpu", "host")})
+// CHECK-NEXT: #pragma omp declare variant(foofoo<int>) match(implementation={vendor(score(0):"unknown")})
+// CHECK-NEXT: #pragma omp declare variant(foofoo<int>) match(implementation={vendor(score(0):"llvm")},device={kind("cpu")})
 // CHECK-NEXT: template<> int barbar<int, 3>();
 
 // CHECK-NEXT: int baz() {
 // CHECK-NEXT: return barbar<int, 3>();
 // CHECK-NEXT: }
 int baz() {
   return barbar<int, 3>();
 }
 
 // CHECK:      template <class C> void h_ref(C *hp, C *hp2, C *hq, C *lin) {
 // CHECK-NEXT: }
 // CHECK-NEXT: template<> void h_ref<double>(double *hp, double *hp2, double *hq, double *lin) {
 // CHECK-NEXT: }
 // CHECK-NEXT: template<> void h_ref<float>(float *hp, float *hp2, float *hq, float *lin) {
 // CHECK-NEXT: }
 template <class C>
 void h_ref(C *hp, C *hp2, C *hq, C *lin) {
 }
 
-// CHECK:      #pragma omp declare variant(h_ref<C>) match(implementation={vendor(score(0):unknown)},device={kind(nohost)})
-// CHECK-NEXT: #pragma omp declare variant(h_ref<C>) match(implementation={vendor(score(0):llvm)},device={kind(gpu)})
+// CHECK:      #pragma omp declare variant(h_ref<C>) match(implementation={vendor(score(0):"unknown")},device={kind("nohost")})
+// CHECK-NEXT: #pragma omp declare variant(h_ref<C>) match(implementation={vendor(score(0):"llvm")},device={kind("gpu")})
 // CHECK-NEXT: template <class C> void h(C *hp, C *hp2, C *hq, C *lin) {
 // CHECK-NEXT: }
 #pragma omp declare variant(h_ref <C>) match(xxx = {})
 #pragma omp declare variant(h_ref <C>) match(implementation={vendor(llvm)}, device={kind(gpu)})
 #pragma omp declare variant(h_ref <C>) match(implementation={vendor(unknown)},device={kind(nohost)})
 template <class C>
 void h(C *hp, C *hp2, C *hq, C *lin) {
 }
 
-// CHECK:      #pragma omp declare variant(h_ref<float>) match(implementation={vendor(score(0):unknown)},device={kind(nohost)})
-// CHECK-NEXT: #pragma omp declare variant(h_ref<float>) match(implementation={vendor(score(0):llvm)},device={kind(gpu)})
+// CHECK:      #pragma omp declare variant(h_ref<float>) match(implementation={vendor(score(0):"unknown")},device={kind("nohost")})
+// CHECK-NEXT: #pragma omp declare variant(h_ref<float>) match(implementation={vendor(score(0):"llvm")},device={kind("gpu")})
 // CHECK-NEXT: template<> void h<float>(float *hp, float *hp2, float *hq, float *lin) {
 // CHECK-NEXT: }
 
 // CHECK-NEXT: template<> void h<double>(double *hp, double *hp2, double *hq, double *lin) {
 // CHECK-NEXT:   h((float *)hp, (float *)hp2, (float *)hq, (float *)lin);
 // CHECK-NEXT: }
 #pragma omp declare variant(h_ref <double>) match(xxx = {})
-#pragma omp declare variant(h_ref <double>) match(implementation={vendor(ibm)},device={kind(cpu,gpu)})
-#pragma omp declare variant(h_ref <double>) match(implementation={vendor(unknown)})
+#pragma omp declare variant(h_ref <double>) match(implementation={vendor(ibm)},device={kind("cpu","gpu")})
+#pragma omp declare variant(h_ref <double>) match(implementation={vendor("unknown")})
 template <>
 void h(double *hp, double *hp2, double *hq, double *lin) {
   h((float *)hp, (float *)hp2, (float *)hq, (float *)lin);
 }
 
 // CHECK: int fn();
 int fn();
 // CHECK: int fn(int);
 int fn(int);
-// CHECK:      #pragma omp declare variant(fn) match(implementation={vendor(score(0):unknown)},device={kind(cpu, gpu)})
-// CHECK-NEXT: #pragma omp declare variant(fn) match(implementation={vendor(score(0):llvm)})
+// CHECK:      #pragma omp declare variant(fn) match(implementation={vendor(score(0):"unknown")},device={kind("cpu", "gpu")})
+// CHECK-NEXT: #pragma omp declare variant(fn) match(implementation={vendor(score(0):"llvm")})
 // CHECK-NEXT: int overload();
 #pragma omp declare variant(fn) match(xxx = {})
 #pragma omp declare variant(fn) match(implementation={vendor(llvm)})
-#pragma omp declare variant(fn) match(implementation={vendor(unknown)},device={kind(cpu,gpu)})
+#pragma omp declare variant(fn) match(implementation={vendor(unknown)},device={kind(cpu,"gpu""")})
 int overload(void);
 
 // CHECK:      int fn_deduced_variant() {
 // CHECK-NEXT: return 0;
 // CHECK-NEXT: }
 auto fn_deduced_variant() { return 0; }
-// CHECK:      #pragma omp declare variant(fn_deduced_variant) match(implementation={vendor(score(0):unknown)},device={kind(gpu, nohost)})
-// CHECK-NEXT: #pragma omp declare variant(fn_deduced_variant) match(implementation={vendor(score(0):llvm)},device={kind(cpu, host)})
+// CHECK:      #pragma omp declare variant(fn_deduced_variant) match(implementation={vendor(score(0):"unknown")},device={kind("gpu", "nohost")})
+// CHECK-NEXT: #pragma omp declare variant(fn_deduced_variant) match(implementation={vendor(score(0):"llvm")},device={kind("cpu", "host")})
 // CHECK-NEXT: int fn_deduced();
 #pragma omp declare variant(fn_deduced_variant) match(xxx = {})
 #pragma omp declare variant(fn_deduced_variant) match(implementation={vendor(llvm)},device={kind(cpu,host)})
 #pragma omp declare variant(fn_deduced_variant) match(implementation={vendor(unknown)},device={kind(gpu,nohost)})
 int fn_deduced();
 
 // CHECK: int fn_deduced_variant1();
 int fn_deduced_variant1();
-// CHECK:      #pragma omp declare variant(fn_deduced_variant1) match(implementation={vendor(score(0):unknown)},device={kind(cpu, host)})
-// CHECK-NEXT: #pragma omp declare variant(fn_deduced_variant1) match(implementation={vendor(score(0):ibm)},device={kind(gpu, nohost)})
+// CHECK:      #pragma omp declare variant(fn_deduced_variant1) match(implementation={vendor(score(0):"unknown")},device={kind("cpu", "host")})
+// CHECK-NEXT: #pragma omp declare variant(fn_deduced_variant1) match(implementation={vendor(score(0):"ibm")},device={kind("gpu", "nohost")})
 // CHECK-NEXT: int fn_deduced1() {
 // CHECK-NEXT: return 0;
 // CHECK-NEXT: }
 #pragma omp declare variant(fn_deduced_variant1) match(xxx = {})
 #pragma omp declare variant(fn_deduced_variant1) match(implementation={vendor(ibm)},device={kind(gpu,nohost)})
 #pragma omp declare variant(fn_deduced_variant1) match(implementation={vendor(unknown)},device={kind(cpu,host)})
 auto fn_deduced1() { return 0; }
 
 // CHECK:      struct SpecialFuncs {
 // CHECK-NEXT: void vd() {
 // CHECK-NEXT: }
 // CHECK-NEXT: SpecialFuncs();
 // CHECK-NEXT: ~SpecialFuncs() noexcept;
 // CHECK-NEXT: void baz() {
 // CHECK-NEXT: }
 // CHECK-NEXT: void bar() {
 // CHECK-NEXT: }
 // CHECK-NEXT: void bar(int) {
 // CHECK-NEXT: }
-// CHECK-NEXT: #pragma omp declare variant(SpecialFuncs::baz) match(implementation={vendor(score(0):unknown)},device={kind(nohost)})
-// CHECK-NEXT: #pragma omp declare variant(SpecialFuncs::bar) match(implementation={vendor(score(0):ibm)},device={kind(cpu)})
+// CHECK-NEXT: #pragma omp declare variant(SpecialFuncs::baz) match(implementation={vendor(score(0):"unknown")},device={kind("nohost")})
+// CHECK-NEXT: #pragma omp declare variant(SpecialFuncs::bar) match(implementation={vendor(score(0):"ibm")},device={kind("cpu")})
 // CHECK-NEXT: void foo1() {
 // CHECK-NEXT: }
-// CHECK-NEXT: #pragma omp declare variant(SpecialFuncs::baz) match(implementation={vendor(score(0):unknown)},device={kind(cpu, host)})
+// CHECK-NEXT: #pragma omp declare variant(SpecialFuncs::baz) match(implementation={vendor(score(0):"unknown")},device={kind("cpu", "host")})
 // CHECK-NEXT: void xxx();
 // CHECK-NEXT: } s;
 struct SpecialFuncs {
   void vd() {}
   SpecialFuncs();
   ~SpecialFuncs();
 
   void baz() {}
   void bar() {}
   void bar(int) {}
 #pragma omp declare variant(SpecialFuncs::baz) match(xxx = {})
 #pragma omp declare variant(SpecialFuncs::bar) match(xxx = {})
 #pragma omp declare variant(SpecialFuncs::bar) match(implementation={vendor(ibm)},device={kind(cpu)})
 #pragma omp declare variant(SpecialFuncs::baz) match(implementation={vendor(unknown)},device={kind(nohost)})
   void foo1() {}
 #pragma omp declare variant(SpecialFuncs::baz) match(implementation={vendor(unknown)},device={kind(cpu, host)})
   void xxx();
 } s;
 
-// CHECK:      #pragma omp declare variant(SpecialFuncs::baz) match(implementation={vendor(score(0):unknown)},device={kind(cpu, host)})
+// CHECK:      #pragma omp declare variant(SpecialFuncs::baz) match(implementation={vendor(score(0):"unknown")},device={kind("cpu", "host")})
 // CHECK-NEXT: void SpecialFuncs::xxx() {
 // CHECK-NEXT: }
 void SpecialFuncs::xxx() {}
 
 // CHECK:      static void static_f_variant() {
 // CHECK-NEXT: }
 static void static_f_variant() {}
-// CHECK:      #pragma omp declare variant(static_f_variant) match(implementation={vendor(score(0):unknown)})
-// CHECK-NEXT: #pragma omp declare variant(static_f_variant) match(implementation={vendor(score(0):llvm)},device={kind(fpga)})
+// CHECK:      #pragma omp declare variant(static_f_variant) match(implementation={vendor(score(0):"unknown")})
+// CHECK-NEXT: #pragma omp declare variant(static_f_variant) match(implementation={vendor(score(0):"llvm")},device={kind("fpga")})
 // CHECK-NEXT: static void static_f() {
 // CHECK-NEXT: }
 #pragma omp declare variant(static_f_variant) match(xxx = {})
 #pragma omp declare variant(static_f_variant) match(implementation={vendor(llvm)},device={kind(fpga)})
 #pragma omp declare variant(static_f_variant) match(implementation={vendor(unknown)})
 static void static_f() {}
 
 // CHECK: void bazzzz() {
 // CHECK-NEXT: s.foo1();
 // CHECK-NEXT: static_f();
 // CHECK-NEXT: }
 void bazzzz() {
   s.foo1();
   static_f();
 }
 
 // CHECK: int fn_linkage_variant();
 // CHECK: extern "C" {
-// CHECK:     #pragma omp declare variant(fn_linkage_variant) match(implementation={vendor(score(0):xxx)},device={kind(cpu, host)})
+// CHECK:     #pragma omp declare variant(fn_linkage_variant) match(implementation={vendor(score(0):"xxx")},device={kind("cpu", "host")})
 // CHECK:     int fn_linkage();
 // CHECK: }
 int fn_linkage_variant();
 extern "C" {
 #pragma omp declare variant(fn_linkage_variant) match(implementation = {vendor(xxx)},device={kind(cpu,host)})
 int fn_linkage();
 }
 
 // CHECK: extern "C" int fn_linkage_variant1()
-// CHECK: #pragma omp declare variant(fn_linkage_variant1) match(implementation={vendor(score(0):xxx)},device={kind(cpu, host)})
+// CHECK: #pragma omp declare variant(fn_linkage_variant1) match(implementation={vendor(score(0):"xxx")},device={kind("cpu", "host")})
 // CHECK: int fn_linkage1();
 extern "C" int fn_linkage_variant1();
-#pragma omp declare variant(fn_linkage_variant1) match(implementation = {vendor(xxx)},device={kind(cpu,host)})
+#pragma omp declare variant(fn_linkage_variant1) match(implementation = {vendor(xxx)},device={kind("cpu","host")})
 int fn_linkage1();
 

clang/test/OpenMP/declare_variant_device_kind_codegen.cpp

 
 #pragma omp declare target
 #ifdef HOST
 #define CORRECT host
 #define SUBSET host, cpu
 #define WRONG host, nohost
 #endif // HOST
 #ifdef CPU
-#define CORRECT cpu
+#define CORRECT "cpu"
 #define SUBSET host, cpu
 #define WRONG cpu, gpu
 #endif // CPU
 #ifdef NOHOST
 #define CORRECT nohost
 #define SUBSET nohost, cpu
-#define WRONG nohost, host
+#define WRONG nohost, "host"
 #endif // NOHOST
 
 int foo() { return 2; }
 
 #pragma omp declare variant(foo) match(device = {kind(CORRECT)})
 int bar() { return 1; }
 
 int bazzz();

clang/test/OpenMP/declare_variant_implementation_vendor_codegen.cpp

 #define HEADER
 
 int foo() { return 2; }
 
 #pragma omp declare variant(foo) match(implementation = {vendor(llvm)})
 int bar() { return 1; }
 
 int bazzz();
-#pragma omp declare variant(bazzz) match(implementation = {vendor(llvm)})
+#pragma omp declare variant(bazzz) match(implementation = {vendor("llvm")})
 int baz() { return 1; }
 
 int test();
 #pragma omp declare variant(test) match(implementation = {vendor(llvm)})
 int call() { return 1; }
 
 static int stat_unused_();
 #pragma omp declare variant(stat_unused_) match(implementation = {vendor(llvm)})
void xxx() {
   (void)s.method();
   (void)s1.method();
 }
 
 int prio() { return 81; }
 int prio1() { return 82; }
 
 #pragma omp declare variant(prio) match(implementation = {vendor(llvm)})
-#pragma omp declare variant(prio1) match(implementation = {vendor(score(1): llvm)})
+#pragma omp declare variant(prio1) match(implementation = {vendor(score(1): "llvm")})
 int prio_() { return 1; }
 
 static int prio2() { return 83; }
 static int prio3() { return 84; }
 static int prio4() { return 84; }
 
 #pragma omp declare variant(prio4) match(implementation = {vendor(score(3): llvm)})
 #pragma omp declare variant(prio2) match(implementation = {vendor(score(5): llvm)})

clang/test/OpenMP/declare_variant_messages.c

 #pragma omp declare variant(foo) match(xxx=yyy) // expected-error {{expected '{' after '='}}
 #pragma omp declare variant(foo) match(xxx=yyy}) // expected-error {{expected '{' after '='}}
 #pragma omp declare variant(foo) match(xxx={) // expected-error {{expected '}' or ',' after ')'}} expected-error {{expected '}'}} expected-note {{to match this '{'}}
 #pragma omp declare variant(foo) match(xxx={})
 #pragma omp declare variant(foo) match(xxx={vvv, vvv})
 #pragma omp declare variant(foo) match(xxx={vvv} xxx) // expected-error {{expected ','}} expected-error {{expected '=' after 'xxx' context selector set name on 'omp declare variant' directive}} expected-error {{context selector set 'xxx' is used already in the same 'omp declare variant' directive}} expected-note {{previously context selector set 'xxx' used here}}
 #pragma omp declare variant(foo) match(xxx={vvv}) xxx // expected-warning {{extra tokens at the end of '#pragma omp declare variant' are ignored}}
 #pragma omp declare variant(foo) match(implementation={xxx}) // expected-warning {{unknown context selector in 'implementation' context selector set of 'omp declare variant' directive, ignored}}
-#pragma omp declare variant(foo) match(implementation={vendor}) // expected-error {{expected '(' after 'vendor'}} expected-error {{expected vendor identifier in 'vendor' context selector of 'implementation' selector set of 'omp declare variant' directive}} expected-error {{expected ')' or ',' after 'vendor name'}} expected-error {{expected ')'}} expected-note {{to match this '('}}
-#pragma omp declare variant(foo) match(implementation={vendor(}) // expected-error {{expected vendor identifier in 'vendor' context selector of 'implementation' selector set of 'omp declare variant' directive}} expected-error {{expected ')' or ',' after 'vendor name'}} expected-error {{expected ')'}} expected-note {{to match this '('}}
-#pragma omp declare variant(foo) match(implementation={vendor()}) // expected-error {{expected vendor identifier in 'vendor' context selector of 'implementation' selector set of 'omp declare variant' directive}}
+#pragma omp declare variant(foo) match(implementation={vendor}) // expected-error {{expected '(' after 'vendor'}} expected-error {{expected expression}} expected-error {{expected ')' or ',' after 'vendor name'}} expected-error {{expected ')'}} expected-note {{to match this '('}} expected-note {{expected context trait string expression or identifier in 'vendor' context selector}}
+#pragma omp declare variant(foo) match(implementation={vendor(}) // expected-error {{expected expression}} expected-error {{expected ')' or ',' after 'vendor name'}} expected-error {{expected ')'}} expected-note {{to match this '('}} expected-note {{expected context trait string expression or identifier in 'vendor' context selector}}
+#pragma omp declare variant(foo) match(implementation={vendor()}) // expected-error {{expected expression}} expected-note {{expected context trait string expression or identifier in 'vendor' context selector}}
 #pragma omp declare variant(foo) match(implementation={vendor(score ibm)}) // expected-error {{expected '(' after 'score'}} expected-warning {{missing ':' after context selector score clause - ignoring}}
-#pragma omp declare variant(foo) match(implementation={vendor(score( ibm)}) // expected-error {{expected ')' or ',' after 'vendor name'}} expected-error {{expected ')'}} expected-error {{use of undeclared identifier 'ibm'}} expected-error {{expected vendor identifier in 'vendor' context selector of 'implementation' selector set of 'omp declare variant' directive}} expected-warning {{missing ':' after context selector score clause - ignoring}} expected-note {{to match this '('}}
-#pragma omp declare variant(foo) match(implementation={vendor(score(2 ibm)}) // expected-error {{expected ')' or ',' after 'vendor name'}} expected-error 2 {{expected ')'}} expected-error {{expected vendor identifier in 'vendor' context selector of 'implementation' selector set of 'omp declare variant' directive}} expected-warning {{missing ':' after context selector score clause - ignoring}} expected-note 2 {{to match this '('}}
+#pragma omp declare variant(foo) match(implementation={vendor(score( ibm)}) // expected-error {{expected ')' or ',' after 'vendor name'}} expected-error {{expected ')'}} expected-error {{use of undeclared identifier 'ibm'}} expected-error {{expected expression}} expected-warning {{missing ':' after context selector score clause - ignoring}} expected-note {{to match this '('}} expected-note {{expected context trait string expression or identifier in 'vendor' context selector}}
+#pragma omp declare variant(foo) match(implementation={vendor(score(2 ibm)}) // expected-error {{expected ')' or ',' after 'vendor name'}} expected-error 2 {{expected ')'}} expected-error {{expected expression}} expected-warning {{missing ':' after context selector score clause - ignoring}} expected-note 2 {{to match this '('}} expected-note {{expected context trait string expression or identifier in 'vendor' context selector}}
 #pragma omp declare variant(foo) match(implementation={vendor(score(foo()) ibm)}) // expected-warning {{missing ':' after context selector score clause - ignoring}} expected-error {{expression is not an integer constant expression}}
 #pragma omp declare variant(foo) match(implementation={vendor(score(5): ibm), vendor(llvm)}) // expected-error {{context trait selector 'vendor' is used already in the same 'implementation' context selector set of 'omp declare variant' directive}} expected-note {{previously context trait selector 'vendor' used here}}
 #pragma omp declare variant(foo) match(implementation={vendor(score(5): ibm), kind(cpu)}) // expected-warning {{unknown context selector in 'implementation' context selector set of 'omp declare variant' directive, ignored}}
 #pragma omp declare variant(foo) match(device={xxx}) // expected-warning {{unknown context selector in 'device' context selector set of 'omp declare variant' directive, ignored}}
-#pragma omp declare variant(foo) match(device={kind}) // expected-error {{expected '(' after 'kind'}} expected-error {{expected 'host', 'nohost', 'cpu', 'gpu', or 'fpga' in 'kind' context selector of 'device' selector set of 'omp declare variant' directive}} expected-error {{expected ')'}} expected-error {{expected ')'}} expected-note {{to match this '('}}
-#pragma omp declare variant(foo) match(device={kind(}) // expected-error {{expected 'host', 'nohost', 'cpu', 'gpu', or 'fpga' in 'kind' context selector of 'device' selector set of 'omp declare variant' directive}} expected-error 2 {{expected ')'}} expected-note {{to match this '('}}
-#pragma omp declare variant(foo) match(device={kind()}) // expected-error {{expected 'host', 'nohost', 'cpu', 'gpu', or 'fpga' in 'kind' context selector of 'device' selector set of 'omp declare variant' directive}}
-#pragma omp declare variant(foo) match(device={kind(score cpu)}) // expected-error {{expected ')' or ',' after 'score'}} expected-error {{unknown 'score' device kind trait in the 'device' context selector set, expected one of 'host', 'nohost', 'cpu', 'gpu' or 'fpga'}}
-#pragma omp declare variant(foo) match(device={kind(score( ibm)}) // expected-error 2 {{expected ')'}} expected-note {{to match this '('}} expected-error {{unknown 'score' device kind trait in the 'device' context selector set, expected one of 'host', 'nohost', 'cpu', 'gpu' or 'fpga'}}
-#pragma omp declare variant(foo) match(device={kind(score(2 gpu)}) // expected-error 2 {{expected ')'}} expected-note {{to match this '('}} expected-error {{unknown 'score' device kind trait in the 'device' context selector set, expected one of 'host', 'nohost', 'cpu', 'gpu' or 'fpga'}}
-#pragma omp declare variant(foo) match(device={kind(score(foo()) ibm)}) // expected-error {{expected ')' or ',' after 'score'}} expected-error {{expected ')'}} expected-note {{to match this '('}} expected-error {{unknown 'score' device kind trait in the 'device' context selector set, expected one of 'host', 'nohost', 'cpu', 'gpu' or 'fpga'}}
-#pragma omp declare variant(foo) match(device={kind(score(5): host), kind(llvm)}) // expected-error {{context trait selector 'kind' is used already in the same 'device' context selector set of 'omp declare variant' directive}} expected-note {{previously context trait selector 'kind' used here}} expected-error {{expected ')' or ',' after 'score'}} expected-note {{to match this '('}} expected-error {{expected ')'}} expected-error {{unknown 'score' device kind trait in the 'device' context selector set, expected one of 'host', 'nohost', 'cpu', 'gpu' or 'fpga'}} expected-error {{unknown 'llvm' device kind trait in the 'device' context selector set, expected one of 'host', 'nohost', 'cpu', 'gpu' or 'fpga'}}
-#pragma omp declare variant(foo) match(device={kind(score(5): nohost), vendor(llvm)}) // expected-warning {{unknown context selector in 'device' context selector set of 'omp declare variant' directive, ignored}} expected-error {{expected ')' or ',' after 'score'}} expected-error {{expected ')'}} expected-note {{to match this '('}} expected-error {{unknown 'score' device kind trait in the 'device' context selector set, expected one of 'host', 'nohost', 'cpu', 'gpu' or 'fpga'}}}
+#pragma omp declare variant(foo) match(device={kind}) // expected-error {{expected '(' after 'kind'}} expected-error {{expected expression}} expected-error {{expected ')'}} expected-error {{expected ')'}} expected-note {{to match this '('}} expected-note {{expected context trait string expression or identifier in 'kind' context selector}}
+#pragma omp declare variant(foo) match(device={kind(}) // expected-error {{expected expression}} expected-error 2 {{expected ')'}} expected-note {{to match this '('}} expected-note {{expected context trait string expression or identifier in 'kind' context selector}}
+#pragma omp declare variant(foo) match(device={kind()}) // expected-error {{expected expression}} expected-note {{expected context trait string expression or identifier in 'kind' context selector}}
+#pragma omp declare variant(foo) match(device={kind(score cpu)}) // expected-error {{expected ')' or ',' after 'kind of device'}}
+#pragma omp declare variant(foo) match(device={kind(score( ibm)}) // expected-error 4 {{expected ')'}} expected-note {{to match this '('}} expected-note 2 {{expected context trait string expression or identifier in 'kind' context selector}} expected-error {{use of undeclared identifier 'ibm'}} expected-error {{expected expression}}
+#pragma omp declare variant(foo) match(device={kind(score(2 gpu)}) // expected-error 2 {{expected ')' or ',' after 'kind of device'}} expected-error 3 {{expected ')'}} expected-note 2 {{to match this '('}} expected-error {{trait expression must be a constant string expression}} expected-error {{trait expression must have a string type, not 'int'}} expected-note {{expected context trait string expression or identifier in 'kind' context selector}} expected-error {{expected expression}}
+#pragma omp declare variant(foo) match(device={kind(score(foo()) ibm)}) // expected-error {{expected ')' or ',' after 'kind of device'}} expected-error {{expected ')'}} expected-error {{trait expression must have a string type, not 'int'}} expected-error {{trait expression must be a constant string expression}}
+#pragma omp declare variant(foo) match(device={kind(score(5): host), kind(llvm)}) // expected-error 2 {{expected ')' or ',' after 'kind of device'}} expected-error {{expected expression}} expected-error {{context trait selector 'kind' is used already in the same 'device' context selector set of 'omp declare variant' directive}} expected-note {{previously context trait selector 'kind' used here}} expected-note {{to match this '('}} expected-error 2 {{expected ')'}} expected-note {{expected context trait string expression or identifier in 'kind' context selector}} expected-error {{trait expression must have a string type, not 'int'}} expected-error {{trait expression must be a constant string expression}}
+#pragma omp declare variant(foo) match(device={kind(score(5): nohost), vendor(llvm)}) // expected-error 2 {{expected ')' or ',' after 'kind of device'}} expected-warning {{unknown context selector in 'device' context selector set of 'omp declare variant' directive, ignored}} expected-error 2 {{expected ')'}} expected-note {{to match this '('}} expected-note {{expected context trait string expression or identifier in 'kind' context selector}} expected-error {{expected expression}} expected-error {{trait expression must have a string type, not 'int'}} expected-error {{trait expression must be a constant string expression}}
 int bar(void);
 
 // expected-error@+2 {{'#pragma omp declare variant' can only be applied to functions}}
 #pragma omp declare variant(foo) match(xxx={})
 int a;
 // expected-error@+2 {{'#pragma omp declare variant' can only be applied to functions}}
 #pragma omp declare variant(foo) match(xxx={})
 #pragma omp threadprivate(a)

clang/test/OpenMP/declare_variant_messages.cpp

 #pragma omp declare variant(foofoo <int>) match(xxx = yyy)   // expected-error {{expected '{' after '='}}
 #pragma omp declare variant(foofoo <int>) match(xxx = yyy }) // expected-error {{expected '{' after '='}}
 #pragma omp declare variant(foofoo <int>) match(xxx = {)     // expected-error {{expected '}' or ',' after ')'}} expected-error {{expected '}'}} expected-note {{to match this '{'}}
 #pragma omp declare variant(foofoo <int>) match(xxx = {})
 #pragma omp declare variant(foofoo <int>) match(xxx = {vvv, vvv})
 #pragma omp declare variant(foofoo <int>) match(xxx = {vvv} xxx) // expected-error {{expected ','}} expected-error {{expected '=' after 'xxx' context selector set name on 'omp declare variant' directive}} expected-error {{context selector set 'xxx' is used already in the same 'omp declare variant' directive}} expected-note {{previously context selector set 'xxx' used here}}
 #pragma omp declare variant(foofoo <int>) match(xxx = {vvv}) xxx // expected-warning {{extra tokens at the end of '#pragma omp declare variant' are ignored}}
 #pragma omp declare variant(foofoo <int>) match(implementation={xxx}) // expected-warning {{unknown context selector in 'implementation' context selector set of 'omp declare variant' directive, ignored}}
-#pragma omp declare variant(foofoo <int>) match(implementation={vendor}) // expected-error {{expected '(' after 'vendor'}} expected-error {{expected vendor identifier in 'vendor' context selector of 'implementation' selector set of 'omp declare variant' directive}} expected-error {{expected ')' or ',' after 'vendor name'}} expected-error {{expected ')'}} expected-note {{to match this '('}}
-#pragma omp declare variant(foofoo <int>) match(implementation={vendor(}) // expected-error {{expected vendor identifier in 'vendor' context selector of 'implementation' selector set of 'omp declare variant' directive}} expected-error {{expected ')' or ',' after 'vendor name'}} expected-error {{expected ')'}} expected-note {{to match this '('}}
-#pragma omp declare variant(foofoo <int>) match(implementation={vendor()}) // expected-error {{expected vendor identifier in 'vendor' context selector of 'implementation' selector set of 'omp declare variant' directive}}
+#pragma omp declare variant(foofoo <int>) match(implementation={vendor}) // expected-error {{expected '(' after 'vendor'}} expected-error {{expected ')' or ',' after 'vendor name'}} expected-error {{expected ')'}} expected-note {{to match this '('}} expected-error {{expected expression}} expected-note {{expected context trait string expression or identifier in 'vendor' context selector}}
+#pragma omp declare variant(foofoo <int>) match(implementation={vendor(}) // expected-error {{expected ')' or ',' after 'vendor name'}} expected-error {{expected ')'}} expected-note {{to match this '('}} expected-error {{expected expression}} expected-note {{expected context trait string expression or identifier in 'vendor' context selector}}
+#pragma omp declare variant(foofoo <int>) match(implementation={vendor()}) // expected-error {{expected expression}} expected-note {{expected context trait string expression or identifier in 'vendor' context selector}}
 #pragma omp declare variant(foofoo <int>) match(implementation={vendor(score ibm)}) // expected-error {{expected '(' after 'score'}} expected-warning {{missing ':' after context selector score clause - ignoring}}
-#pragma omp declare variant(foofoo <int>) match(implementation={vendor(score( ibm)}) // expected-error {{expected ')' or ',' after 'vendor name'}} expected-error {{expected ')'}} expected-error {{use of undeclared identifier 'ibm'}} expected-error {{expected vendor identifier in 'vendor' context selector of 'implementation' selector set of 'omp declare variant' directive}} expected-warning {{missing ':' after context selector score clause - ignoring}} expected-note {{to match this '('}}
-#pragma omp declare variant(foofoo <int>) match(implementation={vendor(score(2 ibm)}) // expected-error {{expected ')' or ',' after 'vendor name'}} expected-error 2 {{expected ')'}} expected-error {{expected vendor identifier in 'vendor' context selector of 'implementation' selector set of 'omp declare variant' directive}} expected-warning {{missing ':' after context selector score clause - ignoring}} expected-note 2 {{to match this '('}}
+#pragma omp declare variant(foofoo <int>) match(implementation={vendor(score( ibm)}) // expected-error {{expected ')' or ',' after 'vendor name'}} expected-error {{expected ')'}} expected-error {{use of undeclared identifier 'ibm'}} expected-warning {{missing ':' after context selector score clause - ignoring}} expected-note {{to match this '('}} expected-error {{expected expression}} expected-note {{expected context trait string expression or identifier in 'vendor' context selector}}
+#pragma omp declare variant(foofoo <int>) match(implementation={vendor(score(2 ibm)}) // expected-error {{expected ')' or ',' after 'vendor name'}} expected-error 2 {{expected ')'}} expected-warning {{missing ':' after context selector score clause - ignoring}} expected-note 2 {{to match this '('}} expected-error {{expected expression}} expected-note {{expected context trait string expression or identifier in 'vendor' context selector}}
 #pragma omp declare variant(foofoo <int>) match(implementation={vendor(score(foofoo <int>()) ibm)}) // expected-warning {{missing ':' after context selector score clause - ignoring}} expected-error {{expression is not an integral constant expression}} expected-note {{non-constexpr function 'foofoo<int>' cannot be used in a constant expression}}
 #pragma omp declare variant(foofoo <int>) match(implementation={vendor(score(5): ibm), vendor(llvm)}) // expected-error {{context trait selector 'vendor' is used already in the same 'implementation' context selector set of 'omp declare variant' directive}} expected-note {{previously context trait selector 'vendor' used here}}
 #pragma omp declare variant(foofoo <int>) match(implementation={vendor(score(5): ibm), kind(cpu)}) // expected-warning {{unknown context selector in 'implementation' context selector set of 'omp declare variant' directive, ignored}}
 #pragma omp declare variant(foofoo <int>) match(device={xxx}) // expected-warning {{unknown context selector in 'device' context selector set of 'omp declare variant' directive, ignored}}
-#pragma omp declare variant(foofoo <int>) match(device={kind}) // expected-error {{expected '(' after 'kind'}} expected-error {{expected 'host', 'nohost', 'cpu', 'gpu', or 'fpga' in 'kind' context selector of 'device' selector set of 'omp declare variant' directive}} expected-error {{expected ')'}} expected-error {{expected ')'}} expected-note {{to match this '('}}
-#pragma omp declare variant(foofoo <int>) match(device={kind(}) // expected-error {{expected 'host', 'nohost', 'cpu', 'gpu', or 'fpga' in 'kind' context selector of 'device' selector set of 'omp declare variant' directive}} expected-error 2 {{expected ')'}} expected-note {{to match this '('}}
-#pragma omp declare variant(foofoo <int>) match(device={kind()}) // expected-error {{expected 'host', 'nohost', 'cpu', 'gpu', or 'fpga' in 'kind' context selector of 'device' selector set of 'omp declare variant' directive}}
-#pragma omp declare variant(foofoo <int>) match(device={kind(score cpu)}) // expected-error {{expected ')' or ',' after 'score'}} expected-error {{unknown 'score' device kind trait in the 'device' context selector set, expected one of 'host', 'nohost', 'cpu', 'gpu' or 'fpga'}}
-#pragma omp declare variant(foofoo <int>) match(device={kind(score( ibm)}) // expected-error 2 {{expected ')'}} expected-note {{to match this '('}} expected-error {{unknown 'score' device kind trait in the 'device' context selector set, expected one of 'host', 'nohost', 'cpu', 'gpu' or 'fpga'}}
-#pragma omp declare variant(foofoo <int>) match(device={kind(score(2 gpu)}) // expected-error 2 {{expected ')'}} expected-note {{to match this '('}} expected-error {{unknown 'score' device kind trait in the 'device' context selector set, expected one of 'host', 'nohost', 'cpu', 'gpu' or 'fpga'}}
-#pragma omp declare variant(foofoo <int>) match(device={kind(score(foofoo <int>()) ibm)}) // expected-error {{expected ')' or ',' after 'score'}} expected-error {{expected ')'}} expected-note {{to match this '('}} expected-error {{unknown 'score' device kind trait in the 'device' context selector set, expected one of 'host', 'nohost', 'cpu', 'gpu' or 'fpga'}}
-#pragma omp declare variant(foofoo <int>) match(device={kind(score(5): host), kind(llvm)}) // expected-error {{context trait selector 'kind' is used already in the same 'device' context selector set of 'omp declare variant' directive}} expected-note {{previously context trait selector 'kind' used here}} expected-error {{expected ')' or ',' after 'score'}} expected-note {{to match this '('}} expected-error {{expected ')'}} expected-error {{unknown 'score' device kind trait in the 'device' context selector set, expected one of 'host', 'nohost', 'cpu', 'gpu' or 'fpga'}} expected-error {{unknown 'llvm' device kind trait in the 'device' context selector set, expected one of 'host', 'nohost', 'cpu', 'gpu' or 'fpga'}}
-#pragma omp declare variant(foofoo <int>) match(device={kind(score(5): nohost), vendor(llvm)}) // expected-warning {{unknown context selector in 'device' context selector set of 'omp declare variant' directive, ignored}} expected-error {{expected ')' or ',' after 'score'}} expected-error {{expected ')'}} expected-note {{to match this '('}} expected-error {{unknown 'score' device kind trait in the 'device' context selector set, expected one of 'host', 'nohost', 'cpu', 'gpu' or 'fpga'}}
+#pragma omp declare variant(foofoo <int>) match(device={kind}) // expected-error {{expected '(' after 'kind'}} expected-error {{expected ')'}} expected-error {{expected ')'}} expected-note {{to match this '('}} expected-error {{expected expression}} expected-note {{expected context trait string expression or identifier in 'kind' context selector}}
+#pragma omp declare variant(foofoo <int>) match(device={kind(}) // expected-error 2 {{expected ')'}} expected-note {{to match this '('}} expected-error {{expected expression}} expected-note {{expected context trait string expression or identifier in 'kind' context selector}}
+#pragma omp declare variant(foofoo <int>) match(device={kind()}) // expected-error {{expected expression}} expected-note {{expected context trait string expression or identifier in 'kind' context selector}}
+#pragma omp declare variant(foofoo <int>) match(device={kind(score cpu)}) // expected-error {{expected ')' or ',' after 'kind of device'}}
+#pragma omp declare variant(foofoo <int>) match(device={kind(score( ibm)}) // expected-error 2 {{expected ')' or ',' after 'kind of device'}} expected-error 2 {{expected ')'}} expected-note {{to match this '('}} expected-error {{expected expression}} expected-error {{use of undeclared identifier 'ibm'}} expected-note 2 {{expected context trait string expression or identifier in 'kind' context selector}}
+#pragma omp declare variant(foofoo <int>) match(device={kind(score(2 gpu)}) // expected-error 2 {{expected ')' or ',' after 'kind of device'}} expected-error 3 {{expected ')'}} expected-note 2 {{to match this '('}} expected-error {{expected expression}} expected-error {{trait expression must have a string type, not 'int'}} expected-error {{trait expression must be a constant string expression}} expected-note {{expected context trait string expression or identifier in 'kind' context selector}}
+#pragma omp declare variant(foofoo <int>) match(device={kind(score(foofoo <int>()) ibm)}) // expected-error 2 {{expected ')' or ',' after 'kind of device'}} expected-error {{trait expression must have a string type, not 'int'}} expected-error {{trait expression must be a constant string expression}}
+#pragma omp declare variant(foofoo <int>) match(device={kind(score(5): host), kind(llvm)}) // expected-error {{context trait selector 'kind' is used already in the same 'device' context selector set of 'omp declare variant' directive}} expected-note {{previously context trait selector 'kind' used here}} expected-note {{to match this '('}} expected-error 2 {{expected ')' or ',' after 'kind of device'}} expected-error 2 {{expected ')'}} expected-error {{expected expression}} expected-error {{trait expression must have a string type, not 'int'}} expected-error {{trait expression must be a constant string expression}} expected-note {{expected context trait string expression or identifier in 'kind' context selector}}
+#pragma omp declare variant(foofoo <int>) match(device={kind(score(5): nohost), vendor(llvm)}) // expected-error 2 {{expected ')' or ',' after 'kind of device'}} expected-warning {{unknown context selector in 'device' context selector set of 'omp declare variant' directive, ignored}} expected-error 2 {{expected ')'}} expected-note {{to match this '('}} expected-error {{expected expression}} expected-error {{trait expression must have a string type, not 'int'}} expected-error {{trait expression must be a constant string expression}} expected-note {{expected context trait string expression or identifier in 'kind' context selector}}
 int bar();
 
 #pragma omp declare variant                            // expected-error {{expected '(' after 'declare variant'}}
 #pragma omp declare variant(                           // expected-error {{expected expression}} expected-error {{expected ')'}} expected-note {{to match this '('}}
 #pragma omp declare variant(foofoo <T>                 // expected-error {{expected ')'}} expected-error {{expected 'match' clause on 'omp declare variant' directive}} expected-note {{to match this '('}}
 #pragma omp declare variant(x)                         // expected-error {{use of undeclared identifier 'x'}}
 #pragma omp declare variant(foo)                       // expected-error {{expected 'match' clause on 'omp declare variant' directive}}
 #pragma omp declare variant(foofoo)                    // expected-error {{expected 'match' clause on 'omp declare variant' directive}}

 #pragma omp declare variant(foofoo <T>) match(xxx = {vvv, vvv})
 #pragma omp declare variant(foofoo <T>) match(user = {score(<expr>) : condition(<expr>)})
 #pragma omp declare variant(foofoo <T>) match(user = {score(<expr>) : condition(<expr>)})
 #pragma omp declare variant(foofoo <T>) match(user = {condition(<expr>)})
 #pragma omp declare variant(foofoo <T>) match(user = {condition(<expr>)})
 #pragma omp declare variant(foofoo <T>) match(xxx = {vvv} xxx) // expected-error {{expected ','}} expected-error {{expected '=' after 'xxx' context selector set name on 'omp declare variant' directive}} expected-error {{context selector set 'xxx' is used already in the same 'omp declare variant' directive}} expected-note {{previously context selector set 'xxx' used here}}
 #pragma omp declare variant(foofoo <T>) match(xxx = {vvv}) xxx // expected-warning {{extra tokens at the end of '#pragma omp declare variant' are ignored}}
 #pragma omp declare variant(foofoo <int>) match(implementation={vendor(score ibm)}) // expected-error {{expected '(' after 'score'}} expected-warning {{missing ':' after context selector score clause - ignoring}}
-#pragma omp declare variant(foofoo <int>) match(implementation={vendor(score( ibm)}) // expected-error {{expected ')' or ',' after 'vendor name'}} expected-error {{expected ')'}} expected-error {{use of undeclared identifier 'ibm'}} expected-error {{expected vendor identifier in 'vendor' context selector of 'implementation' selector set of 'omp declare variant' directive}} expected-warning {{missing ':' after context selector score clause - ignoring}} expected-note {{to match this '('}}
-#pragma omp declare variant(foofoo <int>) match(implementation={vendor(score(C ibm)}) // expected-error {{expected ')' or ',' after 'vendor name'}} expected-error 2 {{expected ')'}} expected-error {{expected vendor identifier in 'vendor' context selector of 'implementation' selector set of 'omp declare variant' directive}} expected-warning {{missing ':' after context selector score clause - ignoring}} expected-note 2 {{to match this '('}}
+#pragma omp declare variant(foofoo <int>) match(implementation={vendor(score( ibm)}) // expected-error {{expected ')' or ',' after 'vendor name'}} expected-error {{expected ')'}} expected-error {{use of undeclared identifier 'ibm'}} expected-warning {{missing ':' after context selector score clause - ignoring}} expected-note {{to match this '('}} expected-error {{expected expression}} expected-note {{expected context trait string expression or identifier in 'vendor' context selector}}
+#pragma omp declare variant(foofoo <int>) match(implementation={vendor(score(C ibm)}) // expected-error {{expected ')' or ',' after 'vendor name'}} expected-error 2 {{expected ')'}} expected-warning {{missing ':' after context selector score clause - ignoring}} expected-note 2 {{to match this '('}} expected-error {{expected expression}} expected-note {{expected context trait string expression or identifier in 'vendor' context selector}}
 #pragma omp declare variant(foofoo <int>) match(implementation={vendor(score(foofoo <int>()) ibm)}) // expected-warning {{missing ':' after context selector score clause - ignoring}} expected-error {{expression is not an integral constant expression}} expected-note {{non-constexpr function 'foofoo<int>' cannot be used in a constant expression}}
 #pragma omp declare variant(foofoo <int>) match(implementation={vendor(score(C+5): ibm), vendor(llvm)}) // expected-error {{context trait selector 'vendor' is used already in the same 'implementation' context selector set of 'omp declare variant' directive}} expected-note {{previously context trait selector 'vendor' used here}}
 #pragma omp declare variant(foofoo <int>) match(implementation={vendor(score(5): ibm), kind(cpu)}) // expected-warning {{unknown context selector in 'implementation' context selector set of 'omp declare variant' directive, ignored}}
 #pragma omp declare variant(foofoo <int>) match(device={xxx}) // expected-warning {{unknown context selector in 'device' context selector set of 'omp declare variant' directive, ignored}}
-#pragma omp declare variant(foofoo <int>) match(device={kind}) // expected-error {{expected '(' after 'kind'}} expected-error {{expected 'host', 'nohost', 'cpu', 'gpu', or 'fpga' in 'kind' context selector of 'device' selector set of 'omp declare variant' directive}} expected-error {{expected ')'}} expected-error {{expected ')'}} expected-note {{to match this '('}}
-#pragma omp declare variant(foofoo <int>) match(device={kind(}) // expected-error {{expected 'host', 'nohost', 'cpu', 'gpu', or 'fpga' in 'kind' context selector of 'device' selector set of 'omp declare variant' directive}} expected-error 2 {{expected ')'}} expected-note {{to match this '('}}
-#pragma omp declare variant(foofoo <int>) match(device={kind()}) // expected-error {{expected 'host', 'nohost', 'cpu', 'gpu', or 'fpga' in 'kind' context selector of 'device' selector set of 'omp declare variant' directive}}
-#pragma omp declare variant(foofoo <int>) match(device={kind(score cpu)}) // expected-error {{expected ')' or ',' after 'score'}} expected-error {{unknown 'score' device kind trait in the 'device' context selector set, expected one of 'host', 'nohost', 'cpu', 'gpu' or 'fpga'}}
-#pragma omp declare variant(foofoo <int>) match(device={kind(score( ibm)}) // expected-error 2 {{expected ')'}} expected-note {{to match this '('}} expected-error {{unknown 'score' device kind trait in the 'device' context selector set, expected one of 'host', 'nohost', 'cpu', 'gpu' or 'fpga'}}
-#pragma omp declare variant(foofoo <int>) match(device={kind(score(C gpu)}) // expected-error 2 {{expected ')'}} expected-note {{to match this '('}} expected-error {{unknown 'score' device kind trait in the 'device' context selector set, expected one of 'host', 'nohost', 'cpu', 'gpu' or 'fpga'}}
-#pragma omp declare variant(foofoo <int>) match(device={kind(score(foofoo <int>()) ibm)}) // expected-error {{expected ')' or ',' after 'score'}} expected-error {{expected ')'}} expected-note {{to match this '('}} expected-error {{unknown 'score' device kind trait in the 'device' context selector set, expected one of 'host', 'nohost', 'cpu', 'gpu' or 'fpga'}}
-#pragma omp declare variant(foofoo <int>) match(device={kind(score(C+5): host), kind(llvm)}) // expected-error {{context trait selector 'kind' is used already in the same 'device' context selector set of 'omp declare variant' directive}} expected-note {{previously context trait selector 'kind' used here}} expected-error {{expected ')' or ',' after 'score'}} expected-note {{to match this '('}} expected-error {{expected ')'}} expected-error {{unknown 'score' device kind trait in the 'device' context selector set, expected one of 'host', 'nohost', 'cpu', 'gpu' or 'fpga'}} expected-error {{unknown 'llvm' device kind trait in the 'device' context selector set, expected one of 'host', 'nohost', 'cpu', 'gpu' or 'fpga'}}
-#pragma omp declare variant(foofoo <int>) match(device={kind(score(C+5): nohost), vendor(llvm)}) // expected-warning {{unknown context selector in 'device' context selector set of 'omp declare variant' directive, ignored}} expected-error {{expected ')' or ',' after 'score'}} expected-error {{expected ')'}} expected-note {{to match this '('}} expected-error {{unknown 'score' device kind trait in the 'device' context selector set, expected one of 'host', 'nohost', 'cpu', 'gpu' or 'fpga'}}
+#pragma omp declare variant(foofoo <int>) match(device={kind}) // expected-error {{expected '(' after 'kind'}} expected-error {{expected ')'}} expected-error {{expected ')'}} expected-note {{to match this '('}} expected-error {{expected expression}} expected-note {{expected context trait string expression or identifier in 'kind' context selector}}
+#pragma omp declare variant(foofoo <int>) match(device={kind(}) // expected-error 2 {{expected ')'}} expected-note {{to match this '('}} expected-error {{expected expression}} expected-note {{expected context trait string expression or identifier in 'kind' context selector}}
+#pragma omp declare variant(foofoo <int>) match(device={kind()}) // expected-error {{expected expression}} expected-note {{expected context trait string expression or identifier in 'kind' context selector}}
+#pragma omp declare variant(foofoo <int>) match(device={kind((C))})
+#pragma omp declare variant(foofoo <int>) match(device={kind(score cpu)}) // expected-error {{expected ')' or ',' after 'kind of device'}}
+#pragma omp declare variant(foofoo <int>) match(device={kind(score( ibm)}) // expected-error 2 {{expected ')' or ',' after 'kind of device'}} expected-error 2 {{expected ')'}} expected-note {{to match this '('}} expected-error {{expected expression}} expected-error {{use of undeclared identifier 'ibm'}} expected-note 2 {{expected context trait string expression or identifier in 'kind' context selector}}
+#pragma omp declare variant(foofoo <int>) match(device={kind(score(C gpu)}) // expected-error 2 {{expected ')' or ',' after 'kind of device'}} expected-error 3 {{expected ')'}} expected-note 2 {{to match this '('}} expected-error {{expected expression}} expected-error {{unknown type name 'C'}} expected-note 2 {{expected context trait string expression or identifier in 'kind' context selector}}
+#pragma omp declare variant(foofoo <int>) match(device={kind(score(foofoo <int>()) ibm)}) // expected-error 2 {{expected ')' or ',' after 'kind of device'}} expected-error {{trait expression must have a string type, not 'int'}} expected-error {{trait expression must be a constant string expression}}
+#pragma omp declare variant(foofoo <int>) match(device={kind(score(C+5): host), kind(llvm)}) // expected-error {{context trait selector 'kind' is used already in the same 'device' context selector set of 'omp declare variant' directive}} expected-note {{previously context trait selector 'kind' used here}} expected-note {{to match this '('}} expected-error 2 {{expected ')' or ',' after 'kind of device'}} expected-error 2 {{expected ')'}} expected-error {{expected expression}} expected-note {{expected context trait string expression or identifier in 'kind' context selector}}
+#pragma omp declare variant(foofoo <int>) match(device={kind(score(C+5): nohost), vendor((C)}) // expected-error 2 {{expected ')' or ',' after 'kind of device'}} expected-warning {{unknown context selector in 'device' context selector set of 'omp declare variant' directive, ignored}} expected-error 2 {{expected ')'}} expected-note {{to match this '('}} expected-error {{expected expression}} expected-note {{expected context trait string expression or identifier in 'kind' context selector}}
 template <typename T, int C>
 T barbar();
 
 // expected-error@+2 {{'#pragma omp declare variant' can only be applied to functions}}
 #pragma omp declare variant(barbar <int>) match(xxx = {})
 int a;
 // expected-error@+2 {{'#pragma omp declare variant' can only be applied to functions}}
 #pragma omp declare variant(barbar <int>) match(xxx = {})

clang/test/OpenMP/declare_variant_mixed_codegen.cpp

 #define HEADER
 
 int foo() { return 2; }
 
 #pragma omp declare variant(foo) match(implementation = {vendor(llvm)}, device={kind(cpu)})
 int bar() { return 1; }
 
 int bazzz();
-#pragma omp declare variant(bazzz) match(implementation = {vendor(llvm)}, device={kind(host)})
+#pragma omp declare variant(bazzz) match(implementation = {vendor(llvm)}, device={kind("host")})
 int baz() { return 1; }
 
 int test();
-#pragma omp declare variant(test) match(implementation = {vendor(llvm)}, device={kind(cpu)})
+#pragma omp declare variant(test) match(implementation = {vendor("llvm")}, device={kind(cpu)})
 int call() { return 1; }
 
 static int stat_unused_();
-#pragma omp declare variant(stat_unused_) match(implementation = {vendor(llvm)}, device={kind(cpu)})
+#pragma omp declare variant(stat_unused_) match(implementation = {vendor("llvm")}, device={kind("cpu")})
 static int stat_unused() { return 1; }
 
 static int stat_used_();
 #pragma omp declare variant(stat_used_) match(implementation = {vendor(llvm)}, device={kind(host)})
 static int stat_used() { return 1; }
 
 int main() { return bar() + baz() + call() + stat_used(); }