Improve transforms for (icmp uPred X * Z, Y * Z) -> (icmp uPred X, Y)
Several cases where missing. 1. `(icmp eq/ne X*Z, Y*Z) [if Z % 2 != 0] -> (icmp eq/ne X, Y)` EQ: https://alive2.llvm.org/ce/z/6_HPZ5 NE: https://alive2.llvm.org/ce/z/c34qSU There was previously an implementation of this that work of `Y` was non-constant, but it was missing if `Y*Z` evaluated to a constant and/or `nsw`/`nuw` where both false. As well it only worked if `Z` was a constant but we can check 1s bit of `KnownBits` to cover more cases. 2. `(icmp eq/ne X*Z, Y*Z) [if Z != 0 and nsw(X*Y) and nsw(Y*Z)] -> (icmp eq/ne X, Y)` EQ: https://alive2.llvm.org/ce/z/6SdAG6 NE: https://alive2.llvm.org/ce/z/fjsq_b This was previously implemented only to work if `Z` was constant, but we can use `isKnownNonZero` to cover more cases. 3. `(icmp uPred X*Y, Y*Z) [if Z != 0 and nuw(X*Y) and nuw(X*Y)] -> (icmp uPred X, Y)` EQ: https://alive2.llvm.org/ce/z/FqWQLX NE: https://alive2.llvm.org/ce/z/2gHrd2 ULT: https://alive2.llvm.org/ce/z/MUAWgZ ULE: https://alive2.llvm.org/ce/z/szQQ2L UGT: https://alive2.llvm.org/ce/z/McVUdu UGE: https://alive2.llvm.org/ce/z/95uyC8 This was previously implemented only for `eq/ne` cases. As well only if `Z` was constant, but again we can use `isKnownNonZero` to cover more cases. Reviewed By: spatel Differential Revision: https://reviews.llvm.org/D142786
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