[Mlir-commits] [mlir] [mlir][Linalg]: Add rewrite pattern to fuse fill with reduce operations (PR #125401)

[llvmlistbot at llvm.org]

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@@ -1893,6 +1893,34 @@ void populateDecomposeWinogradOpsPatterns(RewritePatternSet &patterns);
 /// convert to a `linalg.dot`.
 void populateContractionOpRankReducingPatterns(RewritePatternSet &patterns);
 
+/// Add patterns to fuse a linalg fill operation with a linalg operation.
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MaheshRavishankar wrote:

In general this is not the prefered way of fusing a fill with a reduction. The preferred way is to use tile + fuse approach to fuse at a tile granularity (since fusing fill with its consumer reduction operations results in an inherently imperfectly nested loop computation).  THe main issue here is this adds a conditional to the innermost loop computation which isnt what is generally performant.
But this seems still valid. Could you add some comments explaining the alternatives. 

https://github.com/llvm/llvm-project/pull/125401