[llvm] [AMDGPU][MIR] Serialize SpillPhysVGPRs (PR #113129)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,12 @@
+# RUN: not llc -mtriple=amdgcn-amd-amdhsa -run-pass=none -o /dev/null %s 2>&1 | FileCheck %s --check-prefix=ERR
+
+---
+name: invalid_reg_spill_phys_vgprs
+machineFunctionInfo:
+# ERR: [[@LINE+1]]:21: unknown register name 'notareg'
+  spillPhysVGPRs: ['$notareg']
+body: |
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arsenm wrote:

Check empty string and not a string case 

https://github.com/llvm/llvm-project/pull/113129