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

[Matt Arsenault via llvm-commits]

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@@ -1218,6 +1218,8 @@ bool AMDGPUSwLowerLDS::run() {
     for (auto &K : FuncLDSAccessInfo.NonKernelToLDSAccessMap) {
       Function *Func = K.first;
       DenseSet<GlobalVariable *> &LDSGlobals = K.second;
+      if (Func->isDeclaration() || LDSGlobals.empty())
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arsenm wrote:

How would a declaration end up in this set to begin with? Does this ever fire? 

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