Re: [Qemu-devel] [PATCH] translate-all: wrapped map_exec() in #ifdef

[Peter Maydell]

On 3 November 2014 09:16, Michael Tokarev <address@hidden> wrote:
> 03.11.2014 11:18, SeokYeon Hwang wrote:
>>> --- a/translate-all.c
>>> +++ b/translate-all.c
>>> @@ -270,14 +270,14 @@ bool cpu_restore_state(CPUState *cpu, uintptr_t
>>> retaddr)  }
>>>
>>>  #ifdef _WIN32
>>> -static inline void map_exec(void *addr, long size)
>>> +static __attribute__((unused)) void map_exec(void *addr, long size)
>>>  {
>>>      DWORD old_protect;
>>>      VirtualProtect(addr, size,
>>>                     PAGE_EXECUTE_READWRITE, &old_protect);  }
>
> In which case this function isn't used on windows?  I mean, is it really
> necessary to mark it as unused for win32 case?

It's not necessary, but it means we're consistent between
windows and not-windows. It avoids unnecessary coupling between
how the calling function happens to be implemented and
what defines we put around this utility function.

>>> #else
>>> -static inline void map_exec(void *addr, long size)
>>> +static __attribute__((unused)) void map_exec(void *addr, long size)
>>>  {
>>>      unsigned long start, end, page_size;
>
> How about this instead:
>
> --- a/translate-all.c
> +++ b/translate-all.c
> @@ -276,7 +276,7 @@ static inline void map_exec(void *addr, long size)
>      VirtualProtect(addr, size,
>                     PAGE_EXECUTE_READWRITE, &old_protect);
>  }
> -#else
> +#elif !defined(USE_MMAP)
>  static inline void map_exec(void *addr, long size)
>  {
>      unsigned long start, end, page_size;
>
> ? (Untested, but just to show an idea)... ;)

This breaks for linux-user, where we will define both
USE_STATIC_CODE_GEN_BUFFER and USE_MMAP, and your change won't
define map_exec() but the later ifdef ladder will pick a version
of alloc_code_gen_buffer() that calls it.

-- PMM