[Mlir-commits] [mlir] [mlir][TilingInterface] Allow controlling what fusion is done within tile and fuse (PR #76871)

[lorenzo chelini]

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@@ -97,6 +97,30 @@ struct SCFTileAndFuseOptions {
     tilingOptions = options;
     return *this;
   }
+
+  /// Control function to check if a slice needs to be fused or not,
+  /// The control function recieves
+  /// 1) the slice along which fusion is to be done,
+  /// 2) the producer value that is to be fused
+  /// 3) a boolean value set to `true` if the fusion is from
+  ///    a destination operand.
+  /// It retuns two booleans
+  /// - returns `true` if the fusion should be done through the candidate slice
+  /// - returns `true` if a replacement for the fused producer needs to be
+  ///   yielded from within the tiled loop. Note that is is valid to return
+  ///   `true` only if the slice fused is disjoint across all iterations of the
+  ///   tiled loop. It is upto the caller to ensure that this is true for the
+  ///   fused producers.
+  using ControlFnTy = std::function<std::tuple<bool, bool>(
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chelini wrote:

why not using std::pair?

https://github.com/llvm/llvm-project/pull/76871