[llvm] [LiveRegUnits] Exclude runtime defined liveins when computing liveouts (PR #154325)

[Benjamin Maxwell via llvm-commits]

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@@ -553,8 +553,8 @@ class MachineBasicBlock
         LiveRegI = (*BlockI)->livein_begin();
         if (!advanceToValidPosition())
           return;
-        if (LiveRegI->PhysReg == ExceptionPointer ||
-            LiveRegI->PhysReg == ExceptionSelector)
+        if ((*BlockI)->isEHPad() && (LiveRegI->PhysReg == ExceptionPointer ||
+                                     LiveRegI->PhysReg == ExceptionSelector))
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MacDue wrote:

This was a latent bug, these registers should not be skipped outside of landing-pads (this matches the logic in `operator++`).

https://github.com/llvm/llvm-project/pull/154325