[Mlir-commits] [mlir] [mlir] Extend SCF loopUnrollByFactor to return the result loops (PR #114573)

[Hongtao Yu]

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@@ -111,11 +111,18 @@ LogicalResult coalescePerfectlyNestedSCFForLoops(scf::ForOp op);
 void collapseParallelLoops(RewriterBase &rewriter, scf::ParallelOp loops,
                            ArrayRef<std::vector<unsigned>> combinedDimensions);
 
-/// Unrolls this for operation by the specified unroll factor. Returns failure
-/// if the loop cannot be unrolled either due to restrictions or due to invalid
-/// unroll factors. Requires positive loop bounds and step. If specified,
-/// annotates the Ops in each unrolled iteration by applying `annotateFn`.
-LogicalResult loopUnrollByFactor(
+struct UnrolledLoopInfo {
+  scf::ForOp mainLoopOp;
+  scf::ForOp epilogueLoopOp;
+};
+
+/// Unrolls this for operation by the specified unroll factor. Returns the
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htyu wrote:

Coming back to this, do you think `optional` should be used for both loops? Also I wonder if it is generally recommended to use `optional` instead of `null` for validity checks for milr operations.

https://github.com/llvm/llvm-project/pull/114573