[llvm-branch-commits] [llvm] [SeparateConstOffsetFromGEP] Preserve inbounds flag based on ValueTracking (PR #130617)

[Matt Arsenault via llvm-branch-commits]

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@@ -1079,6 +1081,8 @@ bool SeparateConstOffsetFromGEP::splitGEP(GetElementPtrInst *GEP) {
         // and the old index if they are not used.
         RecursivelyDeleteTriviallyDeadInstructions(UserChainTail);
         RecursivelyDeleteTriviallyDeadInstructions(OldIdx);
+        MayRecoverInbounds =
+            MayRecoverInbounds && computeKnownBits(NewIdx, *DL).isNonNegative();
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arsenm wrote:

Needs some negative tests where computeKnownBits missed by a bit 

https://github.com/llvm/llvm-project/pull/130617