[llvm] [InstCombine] Don't consider aligned_alloc removable if icmp uses result (PR #69474)

[Nikita Popov via llvm-commits]

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@@ -2430,6 +2430,30 @@ static bool isAllocSiteRemovable(Instruction *AI,
         unsigned OtherIndex = (ICI->getOperand(0) == PI) ? 1 : 0;
         if (!isNeverEqualToUnescapedAlloc(ICI->getOperand(OtherIndex), TLI, AI))
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nikic wrote:

I was going to say that the new checks should be in the  `isa<ConstantPointerNull>` path of isNeverEqualToUnescapedAlloc(), but on further consideration, they also apply to the other two cases (e.g. you could compare the result of two required-to-be-null aligned_allocs), so current code structure is good.

https://github.com/llvm/llvm-project/pull/69474