[mlir] Add bufferization option for parallel region check

Author: Max191

mlir/include/mlir/Dialect/Bufferization/IR/BufferizableOpInterface.h

@@ -309,6 +309,11 @@ struct BufferizationOptions {
   /// bufferized or not.
   bool bufferizeFunctionBoundaries = false;
 
+  // Specifies whether to account for parallel regions in RaW analysis. If true,
+  // then writes inside of parallel regions that write to buffers defined
+  // outside of the parallel region will be given a new buffer.
+  bool checkParallelRegions = true;
+
   /// Certain ops have aliasing OpOperand/OpResult invariants (e.g., scf.for).
   /// If this flag is set to `false`, those invariants are no longer enforced
   /// with buffer copies.

mlir/lib/Dialect/Bufferization/Transforms/OneShotAnalysis.cpp

@@ -611,7 +611,7 @@ hasReadAfterWriteInterference(const DenseSet<OpOperand *> &usesRead,
   // Before going through the main RaW analysis, find cases where a buffer must
   // be privatized due to parallelism. If the result of a write is never read,
   // privatization is not necessary (and large parts of the IR are likely dead).
-  if (!usesRead.empty()) {
+  if (options.checkParallelRegions && !usesRead.empty()) {
     for (OpOperand *uConflictingWrite : usesWrite) {
       // Find the allocation point or last write (definition) of the buffer.
       // Note: In contrast to `findDefinitions`, this also returns results of