Re: [Qemu-devel] [PATCH v6 5/7] linux-user: Fix certain argument alignment cases for Mips64

[Aleksandar Markovic]

So true. In v7, I am going to use the style that you suggested.

________________________________________
From: Laurent Vivier address@hidden
Sent: Friday, September 16, 2016 12:29 PM
To: Aleksandar Markovic; address@hidden; address@hidden; address@hidden; 
address@hidden; Leon Alrae; Petar Jovanovic; Miodrag Dinic; Aleksandar Rikalo; 
Aleksandar Markovic
Subject: Re: [Qemu-devel] [PATCH v6 5/7] linux-user: Fix certain argument 
alignment cases for Mips64

Le 16/09/2016 à 13:14, Aleksandar Markovic a écrit :
> From: Aleksandar Markovic <address@hidden>
>
> The function that is changed in this patch is supposed to indicate that
> there was certaing argument rearangement related to 64-bit arguments on
> 32-bit platforms. The background on such rearangements can be found,
> for example, in the man page for syscall(2).
>
> However, for 64-bit Mips architectures there is no such rearangement,
> and this patch reflects it.
>
> Signed-off-by: Aleksandar Rikalo <address@hidden>
> Signed-off-by: Aleksandar Markovic <address@hidden>
> ---
>  linux-user/syscall.c | 9 ++++++++-
>  1 file changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/linux-user/syscall.c b/linux-user/syscall.c
> index ca06943..ee23b29 100644
> --- a/linux-user/syscall.c
> +++ b/linux-user/syscall.c
> @@ -620,7 +620,14 @@ static inline int regpairs_aligned(void *cpu_env) {
>      return ((((CPUARMState *)cpu_env)->eabi) == 1) ;
>  }
>  #elif defined(TARGET_MIPS)
> -static inline int regpairs_aligned(void *cpu_env) { return 1; }
> +static inline int regpairs_aligned(void *cpu_env)
> +{
> +#if TARGET_ABI_BITS == 32
> +    return 1;
> +#else
> +    return 0;
> +#endif
> +}
>  #elif defined(TARGET_PPC) && !defined(TARGET_PPC64)
>  /* SysV AVI for PPC32 expects 64bit parameters to be passed on odd/even pairs
>   * of registers which translates to the same as ARM/MIPS, because we start 
> with
>

To mimic PPC, would be cleaner with:

...
#elif defined(TARGET_MIPS) && TARGET_ABI_BITS == 32
static inline int regpairs_aligned(void *cpu_env) { return 1; }
#else
...

Laurent