[llvm] [SelectionDAG] Improve type legalisation for PARTIAL_REDUCE_MLA (PR #130935)

[Nicholas Guy via llvm-commits]

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@@ -1856,6 +1876,14 @@ AArch64TargetLowering::AArch64TargetLowering(const TargetMachine &TM,
     // Other pairs will default to 'Expand'.
     setPartialReduceMLAAction(MVT::nxv2i64, MVT::nxv8i16, Legal);
     setPartialReduceMLAAction(MVT::nxv4i32, MVT::nxv16i8, Legal);
+
+    setPartialReduceMLAAction(MVT::nxv2i64, MVT::nxv8i64, Custom);
+    setPartialReduceMLAAction(MVT::nxv4i32, MVT::nxv16i32, Custom);
+
+    setPartialReduceMLAAction(MVT::nxv2i64, MVT::nxv4i64, Custom);
+    setPartialReduceMLAAction(MVT::nxv4i32, MVT::nxv8i32, Custom);
+    setPartialReduceMLAAction(MVT::nxv8i16, MVT::nxv16i16, Custom);
+    setPartialReduceMLAAction(MVT::nxv16i8, MVT::nxv32i8, Custom);
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NickGuy-Arm wrote:

Moved these to the commit that introduces the lowering implementation.

https://github.com/llvm/llvm-project/pull/130935