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

[Akshat Oke via llvm-commits]

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@@ -275,6 +275,7 @@ struct SIMachineFunctionInfo final : public yaml::MachineFunctionInfo {
   // TODO: 10 may be a better default since it's the maximum.
   unsigned Occupancy = 0;
 
+  SmallVector<StringValue, 2> SpillPhysVGPRS;
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optimisan wrote:

iinw these are VGPRs used for CSR or FP/BP SGPR spills. This is also related to `SGPRSpillToPhysicalVGPRLanes` map.

Would `PhysVGPRsForSGPRSpills` still be a bit general?

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