[llvm] [WIP][CodeGen] Modifying MBB's liveins representation as into regUnits (PR #129847)

[Jay Foad via llvm-commits]

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@@ -426,10 +427,8 @@ void MachineBasicBlock::print(raw_ostream &OS, ModuleSlotTracker &MST,
     OS.indent(2) << "liveins: ";
 
     ListSeparator LS;
-    for (const auto &LI : liveins()) {
-      OS << LS << printReg(LI.PhysReg, TRI);
-      if (!LI.LaneMask.all())
-        OS << ":0x" << PrintLaneMask(LI.LaneMask);
+    for (const MCRegister Reg : liveins()) {
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jayfoad wrote:

Remove the `const`. (Pointers to const and const references are good, but plain const is not.)

https://github.com/llvm/llvm-project/pull/129847