[llvm] [clang] [InstCombine] Add combines/simplifications for `llvm.ptrmask` (PR #67166)

[Nikita Popov via cfe-commits]

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@@ -978,8 +1031,10 @@ Value *InstCombinerImpl::SimplifyDemandedUseBits(Value *V, APInt DemandedMask,
   }
 
   // If the client is only demanding bits that we know, return the known
-  // constant.
-  if (DemandedMask.isSubsetOf(Known.Zero|Known.One))
+  // constant. We can't directly simplify pointers as a constant because of
+  // pointer provanance.
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nikic wrote:

provenance

https://github.com/llvm/llvm-project/pull/67166