[clang] [llvm] [OpenMP] OpenMP 5.1 "assume" directive parsing support (PR #92731)

[Alexey Bataev via cfe-commits]

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@@ -2013,6 +2064,184 @@ class OMPMergeableClause : public OMPClause {
   }
 };
 
+/// This represents the 'absent' clause in the '#pragma omp assume'
+/// directive.
+///
+/// \code
+/// #pragma omp assume absent(<directive-name list>)
+/// \endcode
+/// In this example directive '#pragma omp assume' has an 'absent' clause.
+class OMPAbsentClause final
+    : public OMPDirectiveListClause<OMPAbsentClause>,
+      private llvm::TrailingObjects<OMPAbsentClause, OpenMPDirectiveKind> {
+  friend OMPDirectiveListClause;
+  friend TrailingObjects;
+
+public:
+  /// Build 'absent' clause.
+  ///
+  /// \param StartLoc Starting location of the clause.
+  /// \param LParenLoc Location of '('.
+  /// \param EndLoc Ending location of the clause.
+  /// \param NumKinds Number of directive kinds listed in the clause.
+  OMPAbsentClause(SourceLocation StartLoc, SourceLocation LParenLoc,
+                  SourceLocation EndLoc, unsigned NumKinds)
+      : OMPDirectiveListClause<OMPAbsentClause>(
+            llvm::omp::OMPC_absent, StartLoc, LParenLoc, EndLoc, NumKinds) {}
+
+  /// Build an empty clause.
+  OMPAbsentClause(unsigned NumKinds)
+      : OMPDirectiveListClause<OMPAbsentClause>(
+            llvm::omp::OMPC_absent, SourceLocation(), SourceLocation(),
+            SourceLocation(), NumKinds) {}
+
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alexey-bataev wrote:

These constructions must be private/protected

https://github.com/llvm/llvm-project/pull/92731