[llvm] [AMDGPU] Improve execz branch removal for async load-to-LDS (PR #192341)

[Matt Arsenault via llvm-commits]

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@@ -401,6 +401,30 @@ bool SIPreEmitPeephole::getBlockDestinations(
   return true;
 }
 
+static bool isAsyncLoadToLDS(unsigned Opc) {
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arsenm wrote:

Can you move this to tablegen? 

https://github.com/llvm/llvm-project/pull/192341