[llvm] [AMDGPU] Eliminate redundant SGPR restores (PR #222680)

[Janek van Oirschot via llvm-commits]

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@@ -12,11 +12,12 @@ machineFunctionInfo:
 body:             |
   bb.0:
     ; CHECK-LABEL: name: merge_sgpr_spill_into_copy_from_exec_lo
-    ; CHECK: S_NOP 0, implicit-def $exec_lo
+    ; CHECK: frame-setup CFI_INSTRUCTION escape 0x0f, 0x04, 0x30, 0x36, 0xe9, 0x02
+    ; CHECK-NEXT: frame-setup CFI_INSTRUCTION undefined $pc_reg
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JanekvO wrote:

Why do these now get added?

https://github.com/llvm/llvm-project/pull/222680