[llvm] [ARM] Invalidate LiveRegPos when erasing current position (PR #226937)

[Eli Friedman via llvm-commits]

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@@ -590,6 +592,13 @@ void ARMLoadStoreOpt::UpdateBaseRegUses(MachineBasicBlock &MBB,
   }
 }
 
+MachineBasicBlock::iterator
+ARMLoadStoreOpt::eraseInstr(MachineBasicBlock::iterator MI) {
+  if (LiveRegsValid && LiveRegPos == MI)
+    LiveRegsValid = false;
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efriedma-quic wrote:

We could try to do something more clever here, like adjust the position to an instruction that isn't getting erased, but probably not worth the effort.

https://github.com/llvm/llvm-project/pull/226937