Re: [Qemu-devel] [HelenOS-devel] [sparc64] Miscomputed minimum of a group of numbers in sparc64 emulation

[Laurent Desnogues <laurent.desnogues@gmail.com>]

On Fri, Jul 1, 2011 at 5:03 PM, Artyom Tarasenko <atar4qemu@gmail.com> wrote:
[...]
>> I find it odd that udivx is using cpu_cc_src and cpu_cc_src2.  Using
>> dedicated local temps seems to fix the issue.
>
> Do we need to copy cpu_src* to further temps at all? IMHO
>
> -                        tcg_gen_mov_tl(cpu_cc_src, cpu_src1);
> -                        tcg_gen_mov_tl(cpu_cc_src2, cpu_src2);
> -                        gen_trap_ifdivzero_tl(cpu_cc_src2);
> -                        tcg_gen_divu_i64(cpu_dst, cpu_cc_src, cpu_cc_src2);
> +                        gen_trap_ifdivzero_tl(cpu_src2);
> +                        tcg_gen_divu_i64(cpu_dst, cpu_src1, cpu_src2);
>
> should do it. Or cpu_src is what you mean by dedicated?

You have to use two local temps here to store cpu_src1
and cpu_src2 because gen_trap_ifdivzero_tl uses
tcg_gen_brcondi_tl (cf tcg/README comment about
local usage and jumps).  Note you'll have to do something
similar in gen_op_sdivx.


Laurent