Re: [Qemu-devel] [PATCH 1/2] linux-user: ppc: mark as long long aligned

[Andreas Färber]

Am 30.09.2012 03:32, schrieb Alexander Graf:
> The PPC32 ABI dictates that long long (64bit) parameters are pass in odd/even
> register pairs. Because unlike ARM and MIPS we start at an odd register 
> number,
> we can reuse the same aligning code that ARM and MIPS use.
> 
> Signed-off-by: Alexander Graf <address@hidden>
> ---
>  linux-user/syscall.c |    6 +++++-
>  1 files changed, 5 insertions(+), 1 deletions(-)
> 
> diff --git a/linux-user/syscall.c b/linux-user/syscall.c
> index 1a38169..8cd56f2 100644
> --- a/linux-user/syscall.c
> +++ b/linux-user/syscall.c
> @@ -587,12 +587,16 @@ extern int setfsgid(int);
>  extern int setgroups(int, gid_t *);
>  
>  /* ARM EABI and MIPS expect 64bit types aligned even on pairs or registers */
> -#ifdef TARGET_ARM 
> +#ifdef TARGET_ARM

For anyone wondering, this is dropping a whitespace at end of line. ;)

>  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; }
> +#elif defined(TARGET_PPC) && !defined(TARGET_PPC64)
> +/* 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 r3 as 
> arg1 */
> +static inline int regpairs_aligned(void *cpu_env) { return 1; }
>  #else
>  static inline int regpairs_aligned(void *cpu_env) { return 0; }
>  #endif

It is obvious that this function has been copied unmodified from mips,
but shouldn't new code use bool and true, assuming that there is no
magic performed on the return value? :)

Andreas

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