[Bug target/123447] [15/16 Regression] ICE: in simplify_gen_subreg_concatn, at lower-subreg.cc:744 with -O2 -mstrict-align and large vectors

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=123447

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[15/16 Regression] ICE: in  |[15/16 Regression] ICE: in
                   |simplify_gen_subreg_concatn |simplify_gen_subreg_concatn
                   |, at lower-subreg.cc:744    |, at lower-subreg.cc:744
                   |with -O2 and large vectors  |with -O2 -mstrict-align and
                   |                            |large vectors

--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Andrew Pinski from comment #1)
> Created attachment 63254 [details]
> Reduced testcase
> 
> This one fails at just -O2 -mstrict-align. (does not need the -fno-tree-dce)

Note this might look like a GIMPLE testcase; it is not. I did start with a
gimple testcase but then converted it into a C one as I went.