[PATCH] D100304: [AArch64][NEON] Match (or (and -a b) (and (a+1) b)) => bit select

[Dave Green via Phabricator via llvm-commits]

dmgreen added inline comments.


================
Comment at: llvm/lib/Target/AArch64/AArch64ISelLowering.cpp:12577
+  // InstCombine does (not (neg a)) => (add a -1).
+  // Try: (or N=(and O=(neg a) b) N=(and O=(add a -1) c)) => (bsl (neg a) b c)
+  // Loop over all combinations of AND operands.
----------------
What do the N= and O= signify?


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Comment at: llvm/test/CodeGen/AArch64/neon-bitselect.ll:11
+
+; Each vbsl_neg_cond_xxxx tests one of the 16 permutations of the operands.
+
----------------
You missed one :-)


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  https://reviews.llvm.org/D100304/new/

https://reviews.llvm.org/D100304