[Mlir-commits] [mlir] [mlir][linalg] Skip rank reduction for unsigned-cast contractions (PR #225993)

[llvmlistbot at llvm.org]

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@@ -963,6 +963,14 @@ struct RankReduceContractionOps : OpRewritePattern<FromOpTy> {
       return rewriter.notifyMatchFailure(
           contractionOp, "ops with user-defined maps are not supported");
     }
+    // linalg.matmul is the only target op with a `cast` attribute.
+    if constexpr (!std::is_same_v<ToOpTy, MatmulOp>) {
+      auto castAttr = dyn_cast_if_present<TypeFnAttr>(
+          contractionOp->getInherentAttr("cast").value_or(Attribute()));
+      if (castAttr && castAttr.getValue() != TypeFn::cast_signed)
+        return rewriter.notifyMatchFailure(
+            contractionOp, "target op cannot represent a non-signed cast");
+    }
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speryt wrote:

Done. I've decided to use `getCast()` instead of `getCastAttr()` which as I understand returns the cast_signed default when the attribute is absent, so no null check is needed.

https://github.com/llvm/llvm-project/pull/225993