[llvm] AlignmentFromAssumptions should not track the load result users (PR #73370)

[Nikita Popov via llvm-commits]

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@@ -226,6 +223,8 @@ bool AlignmentFromAssumptionsPass::processAssumption(CallInst *ACall,
         LI->setAlignment(NewAlignment);
         ++NumLoadAlignChanged;
       }
+      // The user of a Load uses data - not a pointer!
+      AddUsers = false;
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nikic wrote:

This fix looks very incomplete to me. We'll no longer follow users of loads, but still for everything else -- for example, what about a call that accepts and returns a pointer?

I believe we should explicitly listing the instructions for which we want to follow pointers, which are bitcasts, geps, selects and phis, and not anything else.

https://github.com/llvm/llvm-project/pull/73370