[Bug target/126550] RISC-V: auto-vectorization miscompiles duplicated deinterleave store via vcompress/vrgather (rv64gcv_zvl256b)

[rdapp at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126550

--- Comment #2 from Robin Dapp <rdapp at gcc dot gnu.org> ---
Yeah, the permute constant in the constant pool looks dubious:

.LC3:
        .half   0
        .half   1
        .half   0
        .half   1
        .half   0
        .half   1
        .half   0
        .half   1
        .half   0
        .half   1
        .half   0
        .half   1
        .half   0
        .half   1
        .half   0
        .half   1

This should be 0, 1, 0, 1, 2, 3, 2, 3, ...