Re: [boost] BOOST_ASSERT and __assume on MSVC

From: Simon Buchan (simon_at_[hidden])
Date: 2005-09-14 22:47:40

Marcin Kalicinski wrote:
> Hi All,
> 
> Have you considered modifying BOOST_ASSERT to use __assume on MSVC?
> 
> Briefly speaking __assume(expr) is a hint for optimizer that 'expr' 
> evaluates to nonzero. It can help optimize the code. Standalone use of 
> __assume is not recommended because compiler does not check if the 
> assumption is correct, and if it isn't the program is ill formed. But it 
> fits perfectly in ASSERT macro. This way putting many ASSERTs will not only 
> help to verify the code - it will also help the optimizer. Wow!
<snip>
I don't get it, isn't the point of assert that it DOES check them? Or
did you mean something like GCC's __builtin_expect?
http://gcc.gnu.org/onlinedocs/gcc-4.0.1/gcc/Other-Builtins.html#index-g_t_005f_005fbuiltin_005fexpect-2279