[llvm] [AArch64] Separate PNR into its own Register Class (PR #65306)

[Matthew Devereau via llvm-commits]

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@@ -23,8 +11,8 @@ frameInfo:
 machineFunctionInfo:
   hasRedZone:      false
 body:             |
-  bb.0 (%ir-block.0):
-    ; CHECK-LABEL: name: ptrue_d
+  bb.0:
+    ; CHECK-LABEL: name: pnr_to_ppr
     ; CHECK: renamable $pn8 = PTRUE_C_D
     ; CHECK-NEXT: $p0 = ORR_PPzPP $p8, $p8, killed $p8, implicit-def $pn0
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MDevereau wrote:

@david-arm Would you mind chipping in here since you suggested this change here? https://github.com/llvm/llvm-project/pull/65306#discussion_r1322680856 I'm not well versed with implict defs in MIR so I'm not sure if this is necessary or not.

https://github.com/llvm/llvm-project/pull/65306