[llvm] [RFC] implement convergence control in MIR using SelectionDAG (PR #71785)

[Matt Arsenault via llvm-commits]

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@@ -245,6 +245,13 @@ static cl::opt<bool, true> LateCFGStructurize(
   cl::location(AMDGPUTargetMachine::EnableLateStructurizeCFG),
   cl::Hidden);
 
+// Disable structurizer-based control-flow lowering in order to test convergence
+// control tokens. This should eventually be replaced by the wave-transform.
+static cl::opt<bool, true> DisableStructurizer(
+    "amdgpu-disable-structurizer",
+    cl::desc("Disable structurizer for experiments; produces unusable code"),
+    cl::location(AMDGPUTargetMachine::DisableStructurizer), cl::Hidden);
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arsenm wrote:

Maybe make ReallyHidden 

https://github.com/llvm/llvm-project/pull/71785