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

[Jay Foad via llvm-commits]

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@@ -740,11 +740,12 @@ void MIPrinter::print(const MachineBasicBlock &MBB) {
   if (!MBB.livein_empty()) {
     const TargetRegisterInfo &TRI = *MRI.getTargetRegisterInfo();
     OS.indent(2) << "liveins: ";
-    ListSeparator LS;
-    for (const auto &LI : MBB.liveins_dbg()) {
-      OS << LS << printReg(LI.PhysReg, &TRI);
-      if (!LI.LaneMask.all())
-        OS << ":0x" << PrintLaneMask(LI.LaneMask);
+    bool First = true;
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jayfoad wrote:

You should continue to use LS instead of First. You only need to remove the part that prints the lanemask.

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