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

[Benjamin Maxwell via llvm-commits]

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@@ -1781,9 +1781,6 @@ MachineBasicBlock::livein_iterator MachineBasicBlock::livein_begin() const {
 
 MachineBasicBlock::liveout_iterator MachineBasicBlock::liveout_begin() const {
   const MachineFunction &MF = *getParent();
-  assert(MF.getProperties().hasTracksLiveness() &&
-         "Liveness information is accurate");
-
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MacDue wrote:

Note: This assert occurs too early (so asserts for blocks with no successors), removing this is safe as the `liveout_iterator` internally calls `livein_begin()`, which contains the same assert.

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