[InstCombine] Don't sink if it would require dropping deref assumptio… #11828
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fhahn
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jroelofs
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| // Do not sink if there are dereferenceable assumes that would be | ||
| // removed. | ||
| auto II = dyn_cast<IntrinsicInst>(User); | ||
| if (II->getIntrinsicID() != Intrinsic::assume || |
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dyn_cast must always have a nullptr check
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yeah done. (I think currently the only droppable uses appear to be intrinsics)
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or you could do just cast<> if you think that’s better. I’m happy either way.
jroelofs
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LGTM with a check on the dyn_cast's result.
…ns. (llvm#166945) Currently sinking assumes in instcombine drops assumes if they would prevent sinking. Removing dereferenceable assumptions earlier on can inhibit vectorization of early-exit loops in practice. Special-case deferenceable assumptions so that they block sinking. This can be combined with a separate change to drop dereferencebale assumptions after vectorization: https://clang.godbolt.org/z/jGqcx3sbs PR: llvm#166945 (cherry picked from commit 700b77b)
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…ns. (llvm#166945)
Currently sinking assumes in instcombine drops assumes if they would prevent sinking. Removing dereferenceable assumptions earlier on can inhibit vectorization of early-exit loops in practice.
Special-case deferenceable assumptions so that they block sinking. This can be combined with a separate change to drop dereferencebale assumptions after vectorization: https://clang.godbolt.org/z/jGqcx3sbs
PR: llvm#166945
(cherry picked from commit 700b77b)