[llvm] [AArch64][SME2] Add FORM_STRIDED_TUPLE pseudo nodes (PR #116399)

[Sander de Smalen via llvm-commits]

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@@ -34,6 +34,20 @@ def tileslicerange0s4 : ComplexPattern<i32, 2, "SelectSMETileSlice<0,  4>", []>;
 
 def am_sme_indexed_b4 :ComplexPattern<iPTR, 2, "SelectAddrModeIndexedSVE<0,15>", [], [SDNPWantRoot]>;
 
+def FORM_TRANSPOSED_REG_TUPLE_X2_PSEUDO :
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sdesmalen-arm wrote:

I think this needs a description of why we add these pseudos, and a comment that we expand them to REG_SEQUENCE with the post-isel hook if they don't meet certain criteria.

https://github.com/llvm/llvm-project/pull/116399