[clang] [flang] [llvm] [openmp] [Clang][OpenMP][LoopTransformations] Add support for "#pragma omp fuse" loop transformation directive and "looprange" clause (PR #139293)

[Alexey Bataev via llvm-commits]

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@@ -1479,7 +1492,109 @@ class SemaOpenMP : public SemaBase {
   bool checkTransformableLoopNest(
       OpenMPDirectiveKind Kind, Stmt *AStmt, int NumLoops,
       SmallVectorImpl<OMPLoopBasedDirective::HelperExprs> &LoopHelpers,
-      Stmt *&Body, SmallVectorImpl<SmallVector<Stmt *, 0>> &OriginalInits);
+      Stmt *&Body, SmallVectorImpl<SmallVector<Stmt *>> &OriginalInits);
+
+  /// @brief Categories of loops encountered during semantic OpenMP loop
+  /// analysis
+  ///
+  /// This enumeration identifies the structural category of a loop or sequence
+  /// of loops analyzed in the context of OpenMP transformations and directives.
+  /// This categorization helps differentiate between original source loops
+  /// and the structures resulting from applying OpenMP loop transformations.
+  enum class OMPLoopCategory {
+
+    /// @var OMPLoopCategory::RegularLoop
+    /// Represents a standard canonical loop nest found in the
+    /// original source code or an intact loop after transformations
+    /// (i.e Post/Pre loops of a loopranged fusion)
+    RegularLoop,
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alexey-bataev wrote:

Better to commit support for these categories in separate patches, i.e. initially commit support only for single subclass, then add another one and then the third one in separates patches

https://github.com/llvm/llvm-project/pull/139293