[Clang][OpenMP] Only check value if the expression is not instantiation dependent

[tianshilei1992]

Summary

Currently the following case fails:

template<typename Ty>
Ty foo(Ty *addr, Ty val) {
  Ty v;
#pragma omp atomic compare capture
  {
    v = *addr;
    if (*addr > val)
      *addr = val;
  }
  return v;
}

The compiler complains addr is not a lvalue. That's because when an expression
is instantiation dependent, we cannot tell if it is lvalue or not.

[ABataev]

Test is needed

[tianshilei1992]

add tests

[ABataev]

LG

clang/lib/Sema/SemaOpenMP.cpp

protected:
   /// Check if it is a valid conditional expression statement (cond-expr-stmt).
   bool checkCondExprStmt(Stmt *S, ErrorInfoTy &ErrorInfo);
 
   /// Check if all captured values have right type.
   bool checkType(ErrorInfoTy &ErrorInfo) const;
 
   static bool CheckValue(const Expr *E, ErrorInfoTy &ErrorInfo,
                          bool ShouldBeLValue, bool ShouldBeInteger = false) {
+    if (E->isInstantiationDependent())
+      return true;
+
     if (ShouldBeLValue && !E->isLValue()) {
       ErrorInfo.Error = ErrorTy::XNotLValue;
       ErrorInfo.ErrorLoc = ErrorInfo.NoteLoc = E->getExprLoc();
       ErrorInfo.ErrorRange = ErrorInfo.NoteRange = E->getSourceRange();
       return false;
     }
 
-    if (!E->isInstantiationDependent()) {
-      QualType QTy = E->getType();
-      if (!QTy->isScalarType()) {
-        ErrorInfo.Error = ErrorTy::NotScalar;
-        ErrorInfo.ErrorLoc = ErrorInfo.NoteLoc = E->getExprLoc();
-        ErrorInfo.ErrorRange = ErrorInfo.NoteRange = E->getSourceRange();
-        return false;
-      }
-      if (ShouldBeInteger && !QTy->isIntegerType()) {
-        ErrorInfo.Error = ErrorTy::NotInteger;
-        ErrorInfo.ErrorLoc = ErrorInfo.NoteLoc = E->getExprLoc();
-        ErrorInfo.ErrorRange = ErrorInfo.NoteRange = E->getSourceRange();
-        return false;
-      }
-    }
 
     return true;
   }
   };
 
 bool OpenMPAtomicCompareChecker::checkCondUpdateStmt(IfStmt *S,
                                                      ErrorInfoTy &ErrorInfo) {
   auto *Then = S->getThen();
   if (auto *CS = dyn_cast<CompoundStmt>(Then)) {
     if (CS->body_empty()) {
       ErrorInfo.Error = ErrorTy::NoStmt;
       ErrorInfo.ErrorLoc = ErrorInfo.NoteLoc = CS->getBeginLoc();