mirror of
https://github.com/RPCS3/llvm-mirror.git
synced 2025-01-31 20:51:52 +01:00
24c9de9750
The fold 'A - (A & (B - 1))' -> 'A & (0 - B)' added in 8dab0a4a7d691f2704f1079538e0ef29548db159 is too specific. It should/can just be 'A - (A & B)' -> 'A & (~B)' Even if we don't manage to fold `~` into B, we have likely formed `ANDN` node. Also, this way there's less similar-but-duplicate folds. Name: X - (X & Y) -> X & (~Y) %o = and i32 %X, %Y %r = sub i32 %X, %o => %n = xor i32 %Y, -1 %r = and i32 %X, %n https://rise4fun.com/Alive/kOUl See https://bugs.llvm.org/show_bug.cgi?id=44448 https://reviews.llvm.org/D71499