[llvm] [AMDGPU] Common up two local memory size calculations. NFCI. (PR #154784)

[Jay Foad via llvm-commits]

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@@ -1163,7 +1163,7 @@ unsigned getAddressableLocalMemorySize(const MCSubtargetInfo *STI) {
     return 163840;
   if (STI->getFeatureBits().test(FeatureAddressableLocalMemorySize327680))
     return 327680;
-  return 0;
+  return 32768;
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jayfoad wrote:

This is to match the default that is used at GCNSubtarget.cpp:141.

https://github.com/llvm/llvm-project/pull/154784