[Bug middle-end/79649] Memset pattern in named address space crashes compiler or generates wrong code

[amker at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79649

--- Comment #13 from amker at gcc dot gnu.org ---
(In reply to Uroš Bizjak from comment #12)
> The added testcase also ICEs with -O3 -mx32:
> 
> ~/gcc-build/gcc/cc1 -O3 -mx32 -quiet pr79649.c
> pr79649.c: In function ‘f1’:
> pr79649.c:11:1: internal compiler error: in get_use_type, at
> tree-ssa-loop-ivopts.c:3831
>  f1 (unsigned char __seg_gs *s, size_t n)
>  ^~
> 0xff99a1 get_use_type
>         ../../git/gcc/gcc/tree-ssa-loop-ivopts.c:3830
> 0xfff0c8 get_computation_at
>         ../../git/gcc/gcc/tree-ssa-loop-ivopts.c:3847
> 0x1009aba get_computation_cost_at
>         ../../git/gcc/gcc/tree-ssa-loop-ivopts.c:5061
> 0x1009c0f get_computation_cost
>         ../../git/gcc/gcc/tree-ssa-loop-ivopts.c:5089
> 0x100a251 determine_group_iv_cost_address
>         ../../git/gcc/gcc/tree-ssa-loop-ivopts.c:5133

Hmm, there is existing issue in IVOPT that address space information is not
maintained correctly, but this one is earlier than that.  I will have a look.