[llvm] [RISCV] Remove vmv.s.x and vmv.x.s lmul pseudo variants (PR #71501)

[Wang Pengcheng via llvm-commits]

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@@ -7421,10 +7420,15 @@ foreach fvti = AllFloatVectors in {
                (fvti.Scalar fvti.ScalarRegClass:$rs2),
                GPR:$vl, fvti.Log2SEW)>;
 
+    defvar isGroup = !isa<GroupVTypeInfo>(fvti);
+    defvar merge = !if(isGroup,
+                       (!cast<GroupVTypeInfo>(fvti).VectorM1
+                          (EXTRACT_SUBREG $rs1, sub_vrm1_0)),
+                       (fvti.Vector $rs1));
+    defvar pseudo = (PseudoVMV_S_X merge, (XLenVT X0), GPR:$vl, fvti.Log2SEW);
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wangpc-pp wrote:

How about some meaningful names like `vmv`, `pseudoVMV`?

https://github.com/llvm/llvm-project/pull/71501