[Bug target/103197] ppc inline expansion of memcpy/memmove should not use lxsibzx/stxsibx for a single byte

[acsawdey at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103197

--- Comment #5 from acsawdey at gcc dot gnu.org ---
Bisection reveals that this starts with this commit:

20d70cd2719815d9ea853314775ae5787648ece5 is the first bad commit
commit 20d70cd2719815d9ea853314775ae5787648ece5
Author: Alan Modra <amodra@gmail.com>
Date:   Thu May 9 08:37:26 2019 +0930

    [RS6000] PR89271, gcc.target/powerpc/vsx-simode2.c

    This patch makes a number of corrections to rs6000_register_move_cost,
    adds a new register union class, GEN_OR_VSX_REGS, and adjusts insn
    alternative costs to suit.