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

[Matt Arsenault via llvm-commits]

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@@ -300,7 +300,8 @@ void AMDGPUSwLowerLDS::getUsesOfLDSByNonKernels() {
     for (User *V : GV->users()) {
       if (auto *I = dyn_cast<Instruction>(V)) {
         Function *F = I->getFunction();
-        if (!isKernelLDS(F) && F->hasFnAttribute(Attribute::SanitizeAddress))
+        if (!isKernelLDS(F) && F->hasFnAttribute(Attribute::SanitizeAddress) &&
+            !F->isDeclaration())
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arsenm wrote:

This should be testable 

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