[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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@@ -1143,6 +1143,101 @@ class OMPFullClause final : public OMPNoChildClause<llvm::omp::OMPC_full> {
   static OMPFullClause *CreateEmpty(const ASTContext &C);
 };
 
+/// This class represents the 'looprange' clause in the
+/// '#pragma omp fuse' directive
+///
+/// \code {c}
+/// #pragma omp fuse looprange(1,2)
+/// {
+///   for(int i = 0; i < 64; ++i)
+///   for(int j = 0; j < 256; j+=2)
+///   for(int k = 127; k >= 0; --k)
+/// \endcode
+class OMPLoopRangeClause final
+    : public OMPClause,
+      private llvm::TrailingObjects<OMPLoopRangeClause, Expr *> {
+  friend class OMPClauseReader;
+  friend class llvm::TrailingObjects<OMPLoopRangeClause, Expr *>;
+
+  /// Location of '('
+  SourceLocation LParenLoc;
+
+  /// Location of first and count expressions
+  SourceLocation FirstLoc, CountLoc;
+
+  /// Number of looprange arguments (always 2: first, count)
+  unsigned NumArgs = 2;
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alexey-bataev wrote:

Is it always constant? In this case you don't need to use tail allocation, use fixed array

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