[Mlir-commits] [mlir] [mlir][scf] Extend consumer fusion to multiple tilable users (PR #111955)

[llvmlistbot at llvm.org]

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@@ -1699,28 +1702,131 @@ getUntiledConsumerFromSlice(tensor::ParallelInsertSliceOp candidateSliceOp) {
   return getConsumerFromUses(resultingValue, containingOp->getBlock());
 }
 
-/// This utility currently checks whether the loop either :-
-/// 1. Yields exactly one result.
-/// 2. Has consumer op as its first user and other users to be in the same
-/// containing block as that of consumer op's. Currently we clone the loop op
-/// right before the consumer op in order to maintain a valid def-use chain.
-/// This utility thus helps ensuring that no invalid IR is formed due to the
-/// same.
-static LogicalResult checkAssumptionForLoop(Operation *loopOp,
-                                            Operation *consumerOp) {
-  // Check if the loop op yields one result.
-  if (loopOp->getNumResults() == 1)
-    return success();
-  // Check if the consumerOp is the first user of the loopOp and if other users
-  // are in the same containing block as that of consumer op's.
+/// This utility currently checks whether the first userOp of loop is NOT before
+/// the last defineOp of consumer. Currently we need to move the loop op right
+/// before a certain op in order to maintain a valid use-def chain. This utility
+/// thus helps ensuring that no invalid IR is formed. E.g.
+///
+/// ```
+/// %0 = scf.for() {
+///   ...
+/// }
+/// ...
+/// %1 = firstUserOfLoop(%0)
+/// ...
+/// %2 = lastDefOfConsumer
----------------
MaheshRavishankar wrote:

Nit: rename to `lastDefOfConsumer` to `lastDefOfConsumerOperand`

https://github.com/llvm/llvm-project/pull/111955