[llvm] [AMDGPU] Simplify S_WAIT_XCNT insertion. NFC. (PR #145682)

[Jay Foad via llvm-commits]

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@@ -325,10 +321,8 @@ class WaitcntBrackets {
   }
 
   unsigned getRegScore(int GprNo, InstCounterType T) const {
-    if (GprNo < NUM_ALL_VGPRS) {
+    if (GprNo < NUM_ALL_VGPRS)
       return VgprScores[T][GprNo];
-    }
-    assert(isSmemCounter(T));
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jayfoad wrote:

Not needed because `getSgprScoresIdx` asserts anyway

https://github.com/llvm/llvm-project/pull/145682