efriedma added inline comments.
================ Comment at: llvm/lib/Target/AArch64/AArch64ISelLowering.cpp:10676 + ConstantSDNode *C = dyn_cast<ConstantSDNode>(Dup->getOperand(0)); + uint64_t ExtVal = C->getZExtValue(); + ---------------- kmclaughlin wrote: > efriedma wrote: > > Do you need to truncate ExtVal somewhere, so you don't end up with a DUP > > with an over-wide constant? > I've changed the call to `getNode` below that creates the DUP to use > `DAG.getAnyExtOrTrunc` (similar to what we do in LowerSPLAT_VECTOR) I'm specifically concerned that you could end up with something like `(nxv16i8 (dup (i32 0x12345678)))`. ================ Comment at: llvm/lib/Target/AArch64/AArch64ISelLowering.cpp:13300 + // is another unpack: + // 4i32 sign_extend_inreg (4i32 uunpklo(8i16 uunpklo (16i8 opnd)), from 4i8) + // -> ---------------- kmclaughlin wrote: > efriedma wrote: > > It seems a little fragile to assume the inner VT of the SIGN_EXTEND_INREG > > is exactly the type you're expecting here. Probably worth at least adding > > an assertion to encode the assumptions you're making. > I've added an assert above here to make sure the sign_extend_inreg and unpack > types match, is this the assumption you were referring to? We assert that SIGN_EXTEND_INREG has valid operand/result types elsewhere. I was more concerned about the inner VT (`cast<VTSDNode>(N->getOperand(1))->getVT();`). You could end up creating an invalid SIGN_EXTEND_INREG if the type is something weird, like a non-byte-size integer type. CHANGES SINCE LAST ACTION https://reviews.llvm.org/D79587/new/ https://reviews.llvm.org/D79587 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
