[llvm] [RISCV] Fix incorrect fixed vector lowering for VECTOR_DEINTERLEAVE (PR #207254)

[Craig Topper via llvm-commits]

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@@ -13163,6 +13148,83 @@ SDValue RISCVTargetLowering::lowerVECTOR_DEINTERLEAVE(SDValue Op,
     return DAG.getMergeValues(Res, DL);
   }
 
+  // Convert to scalable vectors.
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topperc wrote:

The code on line 13126 that checks for exceeding LMUL=8 is not correct for fixed vectors.

https://github.com/llvm/llvm-project/pull/207254