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

[Sameer Sahasrabuddhe via llvm-commits]

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@@ -1265,10 +1272,15 @@ bool WaitcntGeneratorPreGFX12::applyPreexistingWaitcnt(
   MachineInstr *WaitcntInstr = nullptr;
   MachineInstr *WaitcntVsCntInstr = nullptr;
 
+  LLVM_DEBUG(dbgs() << "PreGFX12::applyPreexistingWaitcnt at: " << *It << "\n");
+
   for (auto &II :
        make_early_inc_range(make_range(OldWaitcntInstr.getIterator(), It))) {
-    if (II.isMetaInstruction())
+    LLVM_DEBUG(dbgs() << "pre-existing iter: " << II << "\n");
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ssahasra wrote:

Same logic. The newline adds whitespace ahead of whatever follows.

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