Re: [Qemu-devel] [PATCH v3 13/34] tcg: Add atomic helpers

[Leon Alrae]

On Sat, Sep 03, 2016 at 09:39:41PM +0100, Richard Henderson wrote:
> --- a/tcg/tcg.h
> +++ b/tcg/tcg.h
> @@ -1175,6 +1175,59 @@ uint64_t helper_be_ldq_cmmu(CPUArchState *env, 
> target_ulong addr,
>  # define helper_ret_ldq_cmmu  helper_le_ldq_cmmu
>  #endif
>  
> +uint32_t helper_atomic_cmpxchgb_mmu(CPUArchState *env, target_ulong addr,
> +                                    uint32_t cmpv, uint32_t newv,
> +                                    TCGMemOpIdx oi, uintptr_t retaddr);
> +uint32_t helper_atomic_cmpxchgw_le_mmu(CPUArchState *env, target_ulong addr,
> +                                       uint32_t cmpv, uint32_t newv,
> +                                       TCGMemOpIdx oi, uintptr_t retaddr);
> +uint32_t helper_atomic_cmpxchgl_le_mmu(CPUArchState *env, target_ulong addr,
> +                                       uint32_t cmpv, uint32_t newv,
> +                                       TCGMemOpIdx oi, uintptr_t retaddr);
> +uint64_t helper_atomic_cmpxchgq_le_mmu(CPUArchState *env, target_ulong addr,
> +                                       uint64_t cmpv, uint64_t newv,
> +                                       TCGMemOpIdx oi, uintptr_t retaddr);
> +uint32_t helper_atomic_cmpxchgw_be_mmu(CPUArchState *env, target_ulong addr,
> +                                       uint32_t cmpv, uint32_t newv,
> +                                       TCGMemOpIdx oi, uintptr_t retaddr);
> +uint32_t helper_atomic_cmpxchgl_be_mmu(CPUArchState *env, target_ulong addr,
> +                                       uint32_t cmpv, uint32_t newv,
> +                                       TCGMemOpIdx oi, uintptr_t retaddr);
> +uint64_t helper_atomic_cmpxchgq_be_mmu(CPUArchState *env, target_ulong addr,
> +                                       uint64_t cmpv, uint64_t newv,
> +                                       TCGMemOpIdx oi, uintptr_t retaddr);

Wouldn't it be useful if tcg.h provided also aliases for _le/_be atomic
helpers (equivalent to helper_ret_X_mmu) so that in target-* code we wouldn't
need to care about the endianness (specifically I'm thinking about SC in MIPS
where I need to select between helper_atomic_cmpxchgl_le_mmu() and 
helper_atomic_cmpxchgl_be_mmu()).

Thanks,
Leon