[llvm] [GVN] Drop Clobber dependency if store may overwrite only the same value (PR #68322)

[Nikita Popov via llvm-commits]

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@@ -577,6 +610,9 @@ MemDepResult MemoryDependenceResults::getSimplePointerDependencyFrom(
         return MemDepResult::getDef(Inst);
       if (isInvariantLoad)
         continue;
+      if (canSkipClobberingStore(SI, MemLoc, MemLocAlign, BatchAA,
+                                 getDefaultBlockScanLimit()))
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nikic wrote:

Hm, do you think it would make sense to pass `Limit` here instead? That way, if we already walked ~100 instructions in the main clobber walk, we're not going to walk another ~100 trying to skip.

https://github.com/llvm/llvm-project/pull/68322