[PATCH] D105088: [InstCombine] Fold IntToPtr/PtrToInt to bitcast

[Eli Friedman via Phabricator via llvm-commits]

efriedma added inline comments.


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Comment at: llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp:4548
+    auto *I = dyn_cast<PtrToIntInst>(CastOp0->getOperand(0));
+    if (I) {
+      Value *P = I->getOperand(0);
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I think you also need to check the size of p1?  If the pointers are in different address spaces, the sizes might not match, so the bitcast will fail to verify.  Again, maybe hard to trigger in practice because the ptrtoint destination type gets canonicalized.


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Comment at: llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp:4552
+      Value *NewOp0 = nullptr;
+      NewOp0 = Builder.CreateBitCast(P, Op0Ty);
+      return new ICmpInst(ICmp.getPredicate(), NewOp0, ICmp.getOperand(1));
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Minor nit: `Value *NewOp0 = Builder.CreateBitCast(P, Op0Ty);`


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  https://reviews.llvm.org/D105088/new/

https://reviews.llvm.org/D105088