[llvm] [AMDGPU][SIInsertWaitCnts] Use RegUnits-based tracking (PR #162077)

[Jay Foad via llvm-commits]

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@@ -1150,27 +1110,31 @@ void WaitcntBrackets::print(raw_ostream &OS) const {
       // Print vgpr scores.
       unsigned LB = getScoreLB(T);
 
-      for (int J = 0; J <= VgprUB; J++) {
-        unsigned RegScore = getRegScore(J, T);
+      for (auto &[ID, Info] : VMem) {
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jayfoad wrote:

Is this going to print the entries in non-deterministic order? That could be annoying, although it is only debug output.

https://github.com/llvm/llvm-project/pull/162077