[llvm] [AMDGPU][SplitKit] Skip any uses that are placed before the current block (PR #177270)

[Matt Arsenault via llvm-commits]

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@@ -218,6 +218,10 @@ void SplitAnalysis::calcLiveBlockInfo() {
     SlotIndex Start, Stop;
     std::tie(Start, Stop) = LIS.getSlotIndexes()->getMBBRange(BI.MBB);
 
+    // Skip any uses that are placed before the current block.
+    while (UseI != UseE && *UseI < Start)
+      ++UseI;
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arsenm wrote:

This looks like just hacking around the assertion, this seems like something that shouldn't happen 

https://github.com/llvm/llvm-project/pull/177270