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

[Matt Arsenault via llvm-commits]

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@@ -274,6 +274,8 @@ void AMDGPUSwLowerLDS::getNonKernelsWithLDSArguments(const CallGraph &CG) {
       Function *CalledFunc = CallerCGN->getFunction();
       if (!CalledFunc)
         continue;
+      if (CalledFunc->isDeclaration())
+        continue;
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arsenm wrote:

Can pull this into the previous condition 

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