Re: [Qemu-devel] [PATCH v4 5/9] target/mips: Add MXU instruction S8LDD

[Richard Henderson]

On 08/31/2018 06:39 AM, Aleksandar Markovic wrote:
>> +    gen_load_mxu_cr(t0);
>> +    tcg_gen_andi_tl(t0, t0, MXUEN);
>> +    tcg_gen_brcondi_tl(TCG_COND_NE, t0, MXUEN, l0);
>> +
>> +    gen_load_gpr(t0, rb);
>> +    tcg_gen_addi_tl(t0, t0, (int8_t)s8);
> 
> I am not sure if this works as desired, with respect to branching. In order 
> to survive branching, tcg variables must be initialized with 
> tcg_temp_local_new(), rather than with tcg_tem_new(). Please retest, and 
> amend if needed.

There is no value live across the branch here.

T0 is used before the branch, yes, but it is also reset
immediately via the gen_load_gpr after the branch.

This is fine.


r~