[Mlir-commits] [mlir] Introduce new Unroll And Jam loop transform for SCF/Affine loops (PR #94142)

[Oleksandr Alex Zinenko]

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@@ -473,6 +496,185 @@ LogicalResult mlir::loopUnrollByFactor(
   return success();
 }
 
+/// Check if bounds of all inner loops are defined outside of `forOp`
+/// and return false if not.
+static bool areInnerBoundsInvariant(scf::ForOp forOp) {
+  auto walkResult = forOp.walk([&](scf::ForOp innerForOp) {
+    if (!forOp.isDefinedOutsideOfLoop(innerForOp.getLowerBound()) ||
+        !forOp.isDefinedOutsideOfLoop(innerForOp.getUpperBound()) ||
+        !forOp.isDefinedOutsideOfLoop(innerForOp.getStep()))
+      return WalkResult::interrupt();
+
+    return WalkResult::advance();
+  });
+  return !walkResult.wasInterrupted();
+}
+
+/// Unrolls and jams this loop by the specified factor.
+LogicalResult mlir::loopUnrollJamByFactor(scf::ForOp forOp,
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ftynse wrote:

If it would introduce more complexity than remove, then let's not do it...

https://github.com/llvm/llvm-project/pull/94142