[PATCH] D87827: [SCEVExpander] Support expanding nonintegral pointers with constant base.

[Eli Friedman via Phabricator via llvm-commits]

efriedma added inline comments.


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Comment at: llvm/lib/Transforms/Utils/ScalarEvolutionExpander.cpp:131
+  // inttoptr only works for integral pointers. For non-integral pointers, we
+  // can create a GEP on i8* null  with the integral value as index.
+  if (Op == Instruction::IntToPtr && DL.isNonIntegralPointerType(PtrTy)) {
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It's probably worth noting the reason we know this is safe.  Semantically, a GEP from null is quite different from an inttoptr: a GEP from null can't be used to access memory.  I guess the reason this is safe is that we know the original IR must also have been a GEP from null.


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  https://reviews.llvm.org/D87827/new/

https://reviews.llvm.org/D87827