[llvm] [AMDGPU] Skip lowerNonKernelLDSAccesses if function is declaration. (PR #106975)

[Matt Arsenault via llvm-commits]

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@@ -1226,6 +1228,8 @@ bool AMDGPUSwLowerLDS::run() {
       auto &K = FuncLDSAccessInfo.NonKernelToLDSAccessMap;
       if (K.find(Func) != K.end())
         continue;
+      if (Func->isDeclaration())
+        continue;
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arsenm wrote:

Do this first before the map lookup 

https://github.com/llvm/llvm-project/pull/106975