[llvm] [AArch64][SVE] Support copy of PPR2 register class in copyPhysReg (PR #216303)

[Sander de Smalen via llvm-commits]

================
@@ -0,0 +1,24 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 6
+# RUN: llc -mtriple=aarch64-linux-gnu -mattr=+sve -run-pass=postrapseudos -simplify-mir -verify-machineinstrs %s -o - | FileCheck %s
+
+---
+name:            copy_ppr2
+alignment:       4
+tracksRegLiveness: true
+liveins:
+  - { reg: '$p0_p1' }
+frameInfo:
+  maxCallFrameSize: 0
+body:             |
+  bb.0:
+    liveins: $p0_p1
+    ; CHECK-LABEL: name: copy_ppr2
+    ; CHECK: liveins: $p0_p1
+    ; CHECK-NEXT: {{  $}}
+    ; CHECK-NEXT: $p2 = ORR_PPzPP $p0, $p0, killed $p0
+    ; CHECK-NEXT: $p3 = ORR_PPzPP $p1, $p1, killed $p1
+    ; CHECK-NEXT: RET_ReallyLR
+    $p2_p3 = COPY killed renamable $p0_p1
----------------
sdesmalen-arm wrote:

nit: maybe also add a test where there is some overlap, e.g. `$p1_p2 = COPY killed $p0_p1`
(and the test for the case I mentioned above, `$p0_p1 = COPY killed $p15_p0`)

https://github.com/llvm/llvm-project/pull/216303