[llvm] [AMDGPU][SIInsertWaitCnts] Gfx12.5 - Refactor xcnt optimization (PR #164357)

[Ryan Mitchell via llvm-commits]

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@@ -2160,19 +2168,11 @@ bool SIInsertWaitcnts::generateWaitcnt(AMDGPU::Waitcnt Wait,
                       << "Update Instr: " << *It);
   }
 
-  // XCnt may be already consumed by a load wait.
-  if (Wait.XCnt != ~0u) {
-    if (Wait.KmCnt == 0 && !ScoreBrackets.hasPendingEvent(SMEM_GROUP))
-      Wait.XCnt = ~0u;
-
-    if (Wait.LoadCnt == 0 && !ScoreBrackets.hasPendingEvent(VMEM_GROUP))
-      Wait.XCnt = ~0u;
-
-    // Since the translation for VMEM addresses occur in-order, we can skip the
-    // XCnt if the current instruction is of VMEM type and has a memory
-    // dependency with another VMEM instruction in flight.
-    if (isVmemAccess(*It))
-      Wait.XCnt = ~0u;
+  // Since the translation for VMEM addresses occur in-order, we can skip the
+  // XCnt if the current instruction is of VMEM type and has a memory
+  // dependency with another VMEM instruction in flight.
+  if (Wait.XCnt != ~0u && isVmemAccess(*It)) {
+    Wait.XCnt = ~0u;
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RyanRio wrote:

Moved to generateWaitcntInstBefore, this aligns with current code much better

https://github.com/llvm/llvm-project/pull/164357