[llvm] [AMDGPU] Fix hidden kernarg preload count inconsistency (PR #116759)

[Matt Arsenault via llvm-commits]

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@@ -1676,11 +1676,13 @@ class GCNUserSGPRUsageInfo {
 
   bool hasPrivateSegmentSize() const { return PrivateSegmentSize; }
 
+  bool hasLDSKernelId() const { return LDSKernelId; }
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arsenm wrote:

I don't know why this is defined in GCNSubtarget.h, it's not related to the subtarget

https://github.com/llvm/llvm-project/pull/116759