[Mlir-commits] [mlir] [mlir][ArmSME] Support 4-way widening outer products (PR #79288)

[Benjamin Maxwell]

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@@ -31,6 +31,65 @@ using namespace mlir;
 using namespace mlir::arm_sme;
 
 namespace {
+
+// Common match failure reasons.
+static constexpr StringLiteral
+    matchFailureNoAccumulator("no accumulator operand");
+static constexpr StringLiteral matchFailureExpectedOuterProductDefOp(
+    "defining op of accumulator must be 'arm_sme.outerproduct'");
+static constexpr StringLiteral matchFailureInconsistentCombiningKind(
+    "combining kind (add or sub) of outer products must match");
+static constexpr StringLiteral matchFailureInconsistentMasking(
+    "unsupported masking, either both outerproducts are masked "
+    "or neither");
+static constexpr StringLiteral matchFailureOuterProductNotSingleUse(
+    "outer product(s) not single use and cannot be removed, no benefit to "
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MacDue wrote:

very nit: It seems more common to prefix constants with `k`, so `kMatch...`

https://github.com/llvm/llvm-project/pull/79288