[llvm] Move SI Lower Control Flow Up (PR #159557)

[Patrick Simmons via llvm-commits]

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@@ -839,6 +850,12 @@ bool SILowerControlFlow::run(MachineFunction &MF) {
   LoweredIf.clear();
   KillBlocks.clear();
 
+  if (Changed)
+    for (MachineBasicBlock &MBB : MF)
+      for (MachineInstr &MI : MBB)
+        if (MI.isBundled())
+          MI.unbundleFromSucc();
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linuxrocks123 wrote:

@arsenm I think you can because someone told me they are otherwise unused at this level.

https://github.com/llvm/llvm-project/pull/159557