[llvm] [llvm-exegesis] Set stack pointer register after starting perf counter (PR #72489)

[Clement Courbet via llvm-commits]

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@@ -60,6 +61,15 @@ static bool generateSnippetSetupCode(
     BBF.addInstructions(ET.setStackRegisterToAuxMem());
   }
   for (const RegisterValue &RV : RegisterInitialValues) {
+    if (GenerateMemoryInstructions) {
+      // If we're generating memory instructions, don't load in the value for
+      // the register with the stack pointer as it will be used later to finish
+      // the setup.
+      if (RV.Register == BBF.MF.getSubtarget()
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legrosbuffle wrote:

put this in a local variable ?

https://github.com/llvm/llvm-project/pull/72489