[llvm] [NFC][AMDGPU] print more info when debugging InsertWaitCnts pass (PR #144629)

[Matt Arsenault via llvm-commits]

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@@ -2437,6 +2457,12 @@ bool SIInsertWaitcnts::insertWaitcntInBlock(MachineFunction &MF,
   Modified |= generateWaitcnt(Wait, Block.instr_end(), Block, ScoreBrackets,
                               OldWaitcntInstr);
 
+  LLVM_DEBUG({
+    dbgs() << "*** Block end state: " << Block.getNumber() << ": ";
+    Block.printName(dbgs());
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arsenm wrote:

Use printMBBReference 

https://github.com/llvm/llvm-project/pull/144629