[llvm] [llvm][CodeGen] Fixed a bug in stall cycle calculation for window scheduler (PR #99451)

[Hua Tian via llvm-commits]

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@@ -485,15 +485,17 @@ int WindowScheduler::calculateMaxCycle(ScheduleDAGInstrs &DAG,
 // ========================================
 int WindowScheduler::calculateStallCycle(unsigned Offset, int MaxCycle) {
   int MaxStallCycle = 0;
+  int CurrentII = MaxCycle + 1;
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huaatian wrote:

Please provide a schematic diagram for the calculation of stall cycles.

https://github.com/llvm/llvm-project/pull/99451