[Mlir-commits] [mlir] [mlir][SCF] Deprecate `linalg::tileToForallOp` and `linalg::tileToForallOpUsingTileSizes` (PR #91878)

[Nicolas Vasilache]

================
@@ -60,7 +70,117 @@ fillInterchangeVector(ArrayRef<int64_t> interchangeVector,
 // tileUsingSCF implementation.
 //===----------------------------------------------------------------------===//
 
-// Check if `stride` evenly divides the trip count `size - offset`.
+/// Verify the tile size options are set in a consistent manner.
+static LogicalResult
+verifyTileSizeOptions(RewriterBase &rewriter, Location loc,
+                      const scf::SCFTilingOptions &options) {
+  // Specifying number of tile is only supported on `scf.forall` op.
+  if (options.numThreadsComputationFunction &&
+      options.loopType != scf::SCFTilingOptions::LoopType::ForallOp) {
+    return rewriter.notifyMatchFailure(
+        loc, "number of tiles/threads can only by specified when loop type is "
+             "set to use `scf.forall`");
+  }
+
+  // If specified, check that the interchange vector is a permutation.
+  if (!options.interchangeVector.empty()) {
+    if (!isPermutationVector(options.interchangeVector)) {
+      return rewriter.notifyMatchFailure(
+          loc, "invalid interchange vector, not a permutation of the entire "
+               "iteration space");
+    }
+  }
+  return success();
+}
+
+/// Compute the tile sizes and num threads values passed in.
+static std::tuple<SmallVector<OpFoldResult>, SmallVector<OpFoldResult>>
+getTileSizes(RewriterBase &rewriter, TilingInterface op,
+             ArrayRef<Range> iterationDomain,
+             const scf::SCFTilingOptions &options) {
+  OpFoldResult zero = rewriter.getIndexAttr(0);
+  SmallVector<OpFoldResult> tileSizes, numThreads;
+  size_t numLoops = iterationDomain.size();
+
+  // Check whether the number of tiles to use is specified.
+  if (options.numThreadsComputationFunction) {
----------------
nicolasvasilache wrote:

general code hygiene: can we avoid the extra levels of nesting by inverting conditionals strategically ?

```
if (!options.numThreadsComputationFunction) {
  assert(options.tileSizeComputationFunction && ...);
  tileSizes = options.tileSizeComputationFunction(rewriter, op);
  tileSizes.resize(numLoops, zero);
  return {tileSizes, numThreads};
}

// Below, the existence of options.numThreadsComputationFunction is guaranteed.
numThreads = options.numThreadsComputationFunction(rewriter, op);
numThreads.resize(numLoops, zero);
if (options.tileSizeComputationFunction) {
  tileSizes = options.tileSizeComputationFunction(rewriter, op);
  tileSizes.resize(numLoops, zero);
  return {tileSizes, numThreads};
}

// Inlined else case
// ...
//

tileSizes.resize(numLoops, zero);
return {tileSizes, numThreads};

```

https://github.com/llvm/llvm-project/pull/91878