[Bug tree-optimization/122880] cmov with neg (or csinv) is not produced instead a mult is produced

[law at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=122880

--- Comment #3 from Jeffrey A. Law <law at gcc dot gnu.org> ---
For RISC-V I see this in the combine dump:

Failed to match this instruction:
(set (reg/v:DI 134 [ t ])
    (if_then_else:DI (eq:DI (reg/v:DI 137 [ a ])
            (reg:DI 150 [ b ]))
        (const_int 2 [0x2])
        (const_int 0 [0])))