// The ellipsis fill might exceed the current output shape because we are
    // also taking account of any to-be-inserted new axes.
    const int ellipsis_filled_dim_size =
        input_size - begin_shape[0] + 1 + absl::popcount(new_axis_mask);

    int64_t begin_mask = strided_slice_op.getBeginMask();
    int64_t end_mask = strided_slice_op.getEndMask();
    int64_t revised_begin_mask = 0;
    int64_t revised_end_mask = 0;

(BitLen64 x) => (SUBFCconst [64] (CNTLZD <typ.Int> x))
(BitLen32 x) => (SUBFCconst [32] (CNTLZW <typ.Int> x))

(PopCount64 ...) => (POPCNTD ...)
(PopCount(32|16|8) x) => (POPCNT(W|W|B) (MOV(W|H|B)Zreg x))

(And(64|32|16|8) ...) => (AND ...)
(Or(64|32|16|8) ...) => (OR ...)
(Xor(64|32|16|8) ...) => (XOR ...)

(Neg(64|32|16|8) ...) => (NEG ...)